Any way to add shortcuts for texture painting blending modes in 2.80?

I think I figured it out - but I couldn't get the normal variable = property to work, so I just spelled it out to get it to work correctly. This is a pie menu add-on that you need to compress to zip before installing, and it is set to use Shift-G to call the pie menu. The included toggles can give you an idea of how you can set up the others you want, or you can set this up to just make the change per menu item instead of toggles if you want.

# -*- coding: utf8 -*-
# python
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#  modify it under the terms of the GNU General Public License
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#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
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# <pep8 compliant>

bl_info = {"name": "Blend Modes Pie",
           "author": "CDMJ",
           "version": (1, 0, 0),
           "blender": (2, 80, 0),
           "location": "",
           "description": "Assistant to help toggle blend modes in Texture Paint",
           "warning": "Alpha version",
           "category": "3D View"}

import bpy
from bpy.types import Menu

#operators
class VIEW3D_OT_add_multiply(bpy.types.Operator):
    """Toggle Add Multiply"""
    bl_idname = "object.toggle_add_multiply"

    bl_label = "Toggle Add Multiply"
    bl_options = { 'REGISTER', 'UNDO' }

    def execute(self, context):

        scene = context.scene
        #new code
        #brush = bpy.context.tool_settings.image_paint.brush.blend
        if bpy.context.tool_settings.image_paint.brush.blend != 'MUL':
            bpy.context.tool_settings.image_paint.brush.blend = 'MUL'
        else:
            bpy.context.tool_settings.image_paint.brush.blend = 'ADD'

        return {'FINISHED'}

class VIEW3D_OT_screen_mix(bpy.types.Operator):
    """Toggle Screen Mix"""
    bl_idname = "object.toggle_screen_mix"

    bl_label = "Toggle Screen Mix"
    bl_options = { 'REGISTER', 'UNDO' }

    def execute(self, context):

        scene = context.scene
        #new code
        #brush = bpy.context.tool_settings.image_paint.brush.blend
        bpy.context.tool_settings.image_paint.brush.blend
        if bpy.context.tool_settings.image_paint.brush.blend != 'MIX':
            bpy.context.tool_settings.image_paint.brush.blend = 'MIX'
        else:
            bpy.context.tool_settings.image_paint.brush.blend = 'SCREEN'

        return {'FINISHED'}

class VIEW3D_OT_color_overlay(bpy.types.Operator):
    """Toggle Color Overaly"""
    bl_idname = "object.toggle_color_overlay"

    bl_label = "Toggle Color Overlay"
    bl_options = { 'REGISTER', 'UNDO' }

    def execute(self, context):

        scene = context.scene
        #new code
        #brush = bpy.context.tool_settings.image_paint.brush.blend
        if bpy.context.tool_settings.image_paint.brush.blend != 'OVERLAY':
            bpy.context.tool_settings.image_paint.brush.blend= 'OVERLAY'
        else:
            bpy.context.tool_settings.image_paint.brush.blend = 'COLOR'

        return {'FINISHED'}

class VIEW3D_OT_add_erase_alpha(bpy.types.Operator):
    """Toggle Add/Erase Alpha"""
    bl_idname = "object.toggle_add_erase_alpha"

    bl_label = "Toggle Add/Erase Alpha"
    bl_options = { 'REGISTER', 'UNDO' }

    def execute(self, context):

        scene = context.scene
        #new code
        #brush = bpy.context.tool_settings.image_paint.brush.blend
        if bpy.context.tool_settings.image_paint.brush.blend != 'ERASE_ALPHA':
            bpy.context.tool_settings.image_paint.brush.blend = 'ERASE_ALPHA'
        else:
            bpy.context.tool_settings.image_paint.brush.blend = 'ADD_ALPHA'

        return {'FINISHED'}

class VIEW3D_OT_hard_soft_light(bpy.types.Operator):
    """Toggle Hard/Soft Light"""
    bl_idname = "object.toggle_hard_soft_light"

    bl_label = "Toggle Hard/Soft Light"
    bl_options = { 'REGISTER', 'UNDO' }

    def execute(self, context):

        scene = context.scene
        #new code
        #brush = bpy.context.tool_settings.image_paint.brush.blend
        if bpy.context.tool_settings.image_paint.brush.blend != 'HARDLIGHT':
            bpy.context.tool_settings.image_paint.brush.blend = 'HARDLIGHT'
        else:
            bpy.context.tool_settings.image_paint.brush.blend = 'SOFTLIGHT'

        return {'FINISHED'}

class VIEW3D_PIE_blendmode(Menu):
    # label is displayed at the center of the pie menu.
    bl_label = "Blend Mode"

    def draw(self, context):
        layout = self.layout

        pie = layout.menu_pie()

        pie.operator("object.toggle_add_multiply", text='ADD/MULTIPLY',
            icon='RENDERLAYERS')
        pie.operator("object.toggle_screen_mix", text='SCREEN/MIX',
            icon='RENDERLAYERS')
        pie.operator("object.toggle_color_overlay", text='COLOR/OVERLAY',
            icon='RENDERLAYERS')
        pie.operator("object.toggle_add_erase_alpha", text='ADD/ERASE ALPHA',
            icon='RENDERLAYERS')
        pie.operator("object.toggle_hard_soft_light", text='HARD/SOFT LIGHT',
            icon='RENDERLAYERS')

_CLASSES = (
    VIEW3D_OT_add_multiply,
    VIEW3D_OT_screen_mix,
    VIEW3D_OT_color_overlay,
    VIEW3D_OT_add_erase_alpha,
    VIEW3D_OT_hard_soft_light
)

def register():
    for cls in _CLASSES:
        bpy.utils.register_class(cls)

    km_list = ['3D View']
    for i in km_list:
        sm = bpy.context.window_manager
        km = sm.keyconfigs.default.keymaps[i]
        kmi = km.keymap_items.new('wm.call_menu_pie', 'G', 'PRESS', shift=True)
        kmi.properties.name = "VIEW3D_PIE_blendmode"

def unregister():
    for cls in _CLASSES:
        bpy.utils.unregister_class(cls)

    km_list = ['3D View']
    for i in km_list:
        sm = bpy.context.window_manager
        km = sm.keyconfigs.default.keymaps[i]
        for kmi in (kmi for kmi in km.keymap_items \
                            if (kmi.idname == "VIEW3D_PIE_blendmode")):
            km.keymap_items.remove(kmi)


If you don't want to use Blender 2.8 yet, you need to use the latest build of 2.79. You can download it here

https://builder.blender.org/download/

Unzip the package and start Blender directly from within the unpacked directory.


how to paint using stencil mode directly in image editor

Yes, you can use the stencil in the Image Editor in 2.8 once you confirm you have usable UVs on your object. Good thing is the Cylinder primitive already comes packaged with basic UV mapping. Just be sure to use the Image Editor to paint and not try the UV Editor since they have been split.


Non-destructive beveling by different amounts on different edges?

Blender can do this with 2 bevel modifiers.

Non destructive and you can change segments at anytime.

The image above shows the use of two different vertex groups. The color options was used.

Use two bevel modifiers.
Create two vertex groups.
Each one uses a different vertex group as indicated by the gold arrows.
There are so many options and ways to do this with the modifier.
There is an option Vertex Group
The above image was a cube and is beveled.


How to put a transparent texture over a material in the blender render?

Quite easy. After you set up your base material (in my case a blue color) go over to the Texture tab.

Add in the texture (it doesn't even need to have an alpha channel).
Now set the Image Mapping to Clip, if you don't the image will tile all over your object. (Do note that the clip option does not work with the Texture or Material shading in the 3D view, you have to be in rendered mode.)
Set the Mapping to UV, it is one of the easiest ways to do a decal type of texture.
Last, do not have this texture influence the alpha at all. The only thing this texture should Influence is the Color.

That's it. Where the texture is, and is not transparent, the texture is displayed; everywhere else the material is displayed.

This is what my material with the texture settings above looks like. The blender logo is a png with an alpha channel, the blue is from my diffuse color in the material.


How do I skip animation between 2 keyframes?

If you're just making a video, add the scene of the animation into the blender VSE and cut out the 101-199 frame range of that animation strip. This will allow you to preview and render your animation without those frames. Additionally, the keyframes will not be affected. If you eventually wish to go back and include the frames again, they will still exist.

Alternatively, you could do as Mr Zak suggested and move all the keyframes from the 200th frame and onward back 99 frames. This would make animation appear as though it is skipping all the frames in the 101-199 range.

To do that, go to drop down menu of blender layouts found in the top left and select the animation layout.

In the dope sheet editor found in the top left, check to see if there are any keyframes in the 101-199 frame range. If there are any, delete them. The range should be made empty.

After the frame range is clear,

Set the vertical bar at the 200th frame and press ] to select all the keyframes to the right of the vertical bar.
Press G to grab your selection, type -99 to move the keyframes back 99 frames and press enter.

The keyframes that were at the 200th frame mark should now be at the 101th frame. Now when you cycle from the 100th frame to the next frame, it should act as though you were cycling straight to the 200th frame.


Plug your texture image into the displacement shocket on the material output node. You can add a (converter>>math>>multiply) node between them to adjust the strenght.

Edit.
Excuse me. I forgot that the "selected to active" means the active doesn't count, just the selected. So what you can do, duplicate the lowpoly object, than select all three model. This method gives much better result with Blender render.


Fluid simulation fluid either pass through effector or it floating above the effector

No, it's not newbie-friendly ;) I was about to write an elaborate answer, but most of the things are quite easy to find out by testing some settings. If you enter a Surface Thickness value (greater than the domain's resolution), you won't need to check Is Planar to make the plane "detectable". If you enable Is Planar it even works with a Surface Thickness of 0.
However, the distance between the fluid and the plane is dependent on both, the domain's resolution and the Surface Thickness (if  > 0). Which means the fluid floats above the surface no matter if the thickness is equal or greater than 0. Thickness will not be added on either top or bottom but around the plane. If you rotate it by 90° so it stands vertical, fluid will keep a distance on both sides (and even on the top edge). By the way: using Is Planar and Surface Thickness will result in even larger gaps than using only one of these options.
Since a plane has a thickness of 0 but all settings to make it affect the fluid will result in strange looking invisible borders, it is best to really use a cuboid with a real thickness instead of a plane. And this thickness should at least be slightly larger than the domain's resolution to work properly.
Here's just a few comparisons between using Is Planar or Surface Thickness and the influence of two domain resolutions, 32 and 64 - which are both quite low for a good simulation. On the left side the plane is horizontal, on the right it's vertical (gosh, now it's an elaborate answer after all):


If you unintentionally set a different object as the Camera (a plane in your case), you can reset it back to camera by either selecting your camera as the Camera in the Scene Properties tab, or you can select the camera and select View > Cameras > Set Active Object as Camera.

You also may want to disable your view locks:


It possibly could be that you have not applied the transform. Try using space to search and looking for 'Apply object transform' and 'Apply visual transform'.

It will also help to have dyntopo checked if you do not have it on already.


In edit mode press Alt+H to unhide the vertices.

Vertices were hidden by pressing H in edit mode.


I don't know how to fix your problem with netrender, but a possible alternative method you could use is to tell each server to write to a shared directory, enable Placeholders and disable Overwrite.

With Overwrite disabled, each server will check to see if a file already exists where it would otherwise write the next frame. If it does, it checks the next frame, and the next, and the next, until it finds a frame where no file exists. Then it will render that frame and write it.

Enabling Placeholders makes the server write a "dummy" file when it starts rendering to "reserve" that filename for the render when is complete. This ensures that one server doesn't start rendering the same frame another server is already rendering but hasn't written yet.


Why does my creature look like this when I try to skin it?

Its because there is a Mirror modifier still unapplied on the mesh. Just click Apply for the Mirror modifier (While in Object Mode) and both halves of the mesh will be editable.


It would be possible to simulate the appearance of the material and the form to some degree while working with reference material like photographs. If you need it the other way around - to know how the reality will look from something you would do in Blender, unfortunately Blender is not designed for that. Tools in Blender are more aimed to achieving visuals, not correctly simulating reality according to measured properties of materials. You could experiment and compare simulations to what happens in reality so it might be possible for you to guess some things based on the simulations, but that might not be an easy task in Blender.

I have attempted to predict the behavior of fabrics before but it was with Marvelous Designer that has way more features than Blender when it comes to cloth simulation. From my experience it is always still guessing and you need a lot of experimentation before you can even start guessing the most basic things. I attempted to predict how a beanbag design would look:

You can see my closest prediction of how the design would look on the right and a photogrammetric reconstruction of the actual bean bag made on the left. The overall form seems to match, but if you look at the details it starts to differ quite a lot because of the limited resolution of the simulations. Keep in mind this is done in software that is a lot more advanced in simulations, so I would expect the results in Blender to be a lot more approximate. Either way this would require a lot of work and a lot of experimentation and in the end is mostly just guessing.


How do (which) things need to be bend and twisted here?

Your object is not vertical :

If you modelize your object like this :

And add a Simple Deform modifier like this :

You will obtain this :

Does it help ?


You don't export anything from Blender to Blender. You simply keep them in a .blend file and append them when you need (File → Append).

However, unused textures are considered as orphan data. In Blender, orphan data are not kept in the .blend file, so they disappear as soon as you close it.

So, in order to force them to stay in your library .blend file, you will have to open the outliner, switch to the orphan data view, and check every data you want to keep. (Those kept have a checkmark, those unkept have an X instead, click the mark to switch between.)


I don't think this is made entirely with the grease pencil. For results like that you should take a look at freestyle line rendering.


Dynamic, script-based animations of object creation and deletion

In that case I propose

preprocess the file into separate files per frame ( Alternatively create a cache dict if you have plenty of RAM, that way you avoid having to deal with writing/reading extra files :) )
store each cloud of atom types and their coordinates something like

this:

 C x y z
 C x y z
 C x y z
 N x y z
 N x y z

write a file reader that can take each frame's file and

on the first frame

check if the object in the next step exists already, skip this step if it does.
create a vertex based mesh object for each type of atom ( ie create a vertex for every atom of one type and put those in an object named something like atom_cloud_C, and do the same for all other atom types ). Meaning, if your file only has 3 C atoms, that your  atom_cloud_C only has 3 verts.
on subsequent frames you read the next frame's file and overwrite the coordinates of each atom, for all atom types.

code:

f_v = list(itertools.chain.from_iterable(verts))
mesh.vertices.foreach_set('co', f_v)
mesh.update()

This produces clouds of atoms as different objects, which get updated every frame.
Then create the spheres that represent each atom type (only need one sphere per atom type)
Then use the dupli feature set to Verts to duplicate the various spheres that represent the atom. (this is a low memory way to display many spheres )
instead of keyframing it all, you can attach a bpy.app.handlers.frame_change_pre to perform a function on each frame change (pre or post), examples for this can be found in the documentation.


You can offset the spline along whatever axis you want using the Transform Spline node, all control points are maintained.

To change the location of control points, use the Spline Info node to get the location of the control points, perform whatever transformation you want to do and create a spline from the result again using the Spline From Points node:


Use Camera/Window projection when texture painting?

You can give your model a secondary UV map to base your mask on, using Project from View through your camera you have sized to match your mask image. Call up the mask image in the Masking tab either in the mask tool itself or in the Texture Paint tool, and invert as you need to.
Add your image to the image editor to see the scale and set up your camera to match.

Added a second UV mapping layer

Before painting, showing the original mapping active for target image

Here is the paint on top of the mask, holes showing through


Rigid Body Problem - objects not colliding

There are a number of important things to check when setting up a Rigid Body simulation :

Use the correct Collision Shape - on your example screenshot you show the first object as having Shape set to Mesh but check that all of your objects are similarly set. Convex Hull is more efficient but Mesh shape is required for interlocking objects and/or more complicated (non-convex) meshes.
Use a realistic scale - your example screenshot shows your Collision Sensitivity Margin set to 4cm which implies that 1 Blender Unit equates to 1 metre. Each link of your chain appears to be many blender units in size (when compared to the Grid which is visible in the screenshot). This means you have links that are many metres in length and will therefore behave as very large objects, with very large forces as they interact with each other. This can cause unstable simulations - especially if your 'steps per second' simulation setting is too low.
Ensure each object has its Scale applied - it's not clear if that is the case with your example. In order for Rigid Body objects to behave realistically, they need to have a consistent Scale in each of the X,Y,Z directions. To achieve this, select all links in the chain and press Ctrl+A and select 'Scale'.
Ensure the origin of each mesh is at its 'centre of gravity' - if you've created your chain using an Array modifier, split into its separate parts then the origins may be in the wrong place. Select the objects, click Set Origin in the tool panel (T) and select 'Origin to Centre of Mass'. A wrongly positioned origin (especially if it is outside the bounds of the mesh) can produce some very odd simulation results.
If the simulation still behaves erratically, you may need to increase the precision of the simulation - in particular the Scene/Rigid Body World/Steps Per Second - don't increase it too high as this can also cause problems with the simulation accuracy.

If you have addressed all of the above and still have a misbehaving simulation then it would help to upload an animation of what is occurring in your simulation (can tell a lot about how it's set up by how it moves and interacts) and/or upload your Blend file.

In order to demonstrate the difference applying the scale can make, here's a simulation where the chains have not had the scale applied (and have been stretched in one direction and have the scale of (1.0,1.0,5.0)) :

And here's the same simulation with the only difference being that the scale has been 'applied' (so they meshes are identical but scaled as (1.0,1.0,1.0)) :


Why doesn't beveling work on both faces of this model?

Maybe you've scaled your object in the Y axis in Object mode, it makes the bevel completely deformed. So before any bevel, apply the scale with a ctrl A.


Remove all vertices connected to one or less edges?

⇧ ShiftG > Amount of Connecting edges works for me.

You will have to select a vertex with no connecting edges and a vertex with one connecting edge in order to select all vertices with one or fewer connecting edges at once:

There are also Greater than and Less than options in the Redo panel (F6).


How do I make a rectangular mesh subdivided evenly with square faces / quads?

Use loop cuts to manually subdivide the first time.  CTRL-R

Start by making a certain number of loop cuts across the short side.  Just enough to know loop cuts on the long side will result in a square.

Then make the necessary loop cuts on the long side to complete the square (or close enough to it.  In this example, I only needed one more on the long side

From there, you can subdivide normally and keep your square proportions.  If you really want to get perfect about it, and the dimensions of your plane are conducive to it, you could calculate the number of loop cuts needed by subdividing the dimensions of your plane mathmatically.  But usually not necessary.


When is acceptable to have disconnected geometry?

This technique has lots of advantages, the biggest of which is of course speed of modeling. There are also some drawbacks you might want to consider:

Stacking is troublesome if you need bevelling. The intersections will stay sharp, no matter what.

Freestyle won't produce the result you're after. It uses face boundaries to find edges and there are none.

In the past, Blender sometimes had trouble to precisely calculate the intersections, resulting in a jagged appearance. I haven't noticed that lately so it might be fine.
If you deform the surface, the object might move relative to one another, resulting in a shift of the edge. Or in Z-fighting.
Transparent materials will show that you tried to cheat. Nothing against cheating in 3D as long as you can get away with it. The left image is how it should look, the right is how it looks if it's stacked. This effect gets worse when you rotate around the object.

If you don't use it for joints or movable parts but just for speeding up the modeling, and you don't trim the parts inside the model, it always results in unnecessary geometry. Depends on the case what's more important. But even with trimming, it's still faster than manually connecting the detail or cleaning up boolean artefacts.
Adding small details has the advantage of not distorting the big geometry which can be quite time consuming to repair or plan in advance.
Tools like the Loop Cut will ignore the detail  when you work on the main mesh.
It affects your UV mapping workflow.
One of the biggest factors still is screen size. Extreme closeups will reveal possible problems. If it's just a small detail, you can employ a lot of simplification techniques, saving time.


Py: List materials with texture used by mesh

Using blender internal, a material can use up to 18 textures to get it's final appearance. An objects face can have one material assigned to it, any and all textures in that material are used by the face.

In object mode you can get the texture used by each face with

obj = bpy.context.object
for f in obj.data.polygons:
    for t in obj.material_slots[f.material_index].material.texture_slots:
        if t is not None:
            print("Face %d uses texture %s"%(f.index,t.name))

Of course this is using Blender Internal, for cycles you will need to walk through the nodetree to find the nodes your interested in.


Quad-only topology at the edge of a chamfer

Add a vertex at the middle of the triangle. You will need an extra edge loop at each of the horizontal and vertical edges.


Compositor setting in Blender Internal: How to properly make a split RGB effect on further objects using Z?

One challenging aspect of this effect is that the strength of the color shift increase with the distance from the object that is in focus. This is solved in the compositor by using the depth and a user supplied distance that is considered in focus, to calculate the intensity of the applied color shift.

Before

After

Unfortunately the color shift produces artifacts at the image border. Cropping by the number of shifted pixels may be necessary for good looking results. The proper solution would be to mirror the image along the borders before performing the shift to avoid artifacts in the border region.

Cropped

The Depth Color Shift node setup uses the normalized depth as input to the Gaussian function. This allows to have a nice spread of the intensity values instead of a sharp peak for the depth that is in focus. The output is normalized and inverted, since the effect is supposed to be the smallest at the given depth.

The Gauss Function implements the Gaussian function.

The Shift Color shifts both the individual color channels and the intensity values. The latter is used as blending factor to ensure that the effect strength is applied correctly  depending on the distance.

The parameters of the Depth Color Shift node are:

Focus Distance: Distance where the effect is the weakest (is used as $μ$ in the Gaussian function)
$σ$: Parameter of the Gaussian function, controls the variance
R Shift X: Shift of the red color channel along the x-axis
R Shift Y: Shift of the red color channel along the y-axis
G Shift X: Shift of the green color channel along the x-axis
G Shift Y: Shift of the green color channel along the y-axis
B Shift X: Shift of the blue color channel along the x-axis
B Shift Y: Shift of the blue color channel along the y-axis

The Intensity output of the Depth Color Shift node allows you to see the strength of the effect (black = no strength, white = full strength)

The example file below is for Blender 2.80, however the same node setup should work in 2.79 as well.


UV texture paint not working on sharp edges/tips?

Turn off backface culling in the options of your brush in paint mode.


It's just a guess, but you might want to use a external Python 3 for using Blender scripts instead of the bundled one. Since the installer does automatically set the registry, Pillow'll probably recognize it.


For EEVEE:

Turn “Transmission” all the way up.
Turn alpha down to about 0.5
Set blend method to either hashed or blend.


The axes when I move/rotate/scale is different from those of the world

You can choose whatever transform orientation you want to use instead of Local. if you are constraining transforms to some axis with shortcuts x, y, z or middle mouse button, you can just hit it again with Local orientation set to temporarily use global orientation anyway:

This works the other way around if you have global orientation selected as well.


The "reset of the scale" flips and destroys my normals

It should work to duplicate your object, before applying scale, and use a Data Transfer Modifier to transfer the custom normals from the duplicate object to the corrected object:

Hopefully that does the trick.


Best way to animate 2d missiles in Blender

you can create a particle system to emmit particles toward a negative force field.

Then assign a missile object to those particles.

Or you can make the particles follow boids physics and this is what I get.


Texture is rendered as a flat colored surface

When UV unwrapping, I hadn't selected all the sides of the object. Press A to select everything, then U to unwrap it all. Marking seams and unwrapping does nothing when there is nothing selected and there is no error message.


Using Inverse Kinematics and/or Pole Targets to move hair bones in unison?

After some heavy research, I found that one simply can't assign multiple bones to a parent bone under the guise of copy rotation or any other such restraint option; it's a 1:1 bone ratio situation. But! Not to worry: I just created a few different bone groups, assigned each hair strand to a group according to its location on the head, and that did it. Still... I wish I could get the hair bones to rotate on its head instead of its base. It seems like I can do that but it'd take some wonky manipulation that doesn't seem worth the cost.

At any rate, this feels like a limitation Blender shouldn't have. I should be able to control multiple bones with one bone like a type of Pole Target bone without the inverse kinematics.


How do I get the inch measurement around this cup?

I think once it goes below 1" it automatically reads thousandths. One thing that could be done is turn units back to None. This issue seems to have been fixed in 2.8 ,but doesn't help in 2.79.

None in 2.79

Inches in 2.8


How to use rigidbody simulation for animation?

As of Blender 2.66, you can press Rigid Body in Properties > Physics.

To enable and disable control of the rigid body with the animation system, keyframe the Animated checkbox.

See the wiki for documentation.


Go with the Nvidia.  Performance aside, CUDA works better with Cycles.  Until recently, OpenCL was not even supported in Cycles so it is not as bug-free and stable as CUDA.  Another thing to consider is that usually new features are supported on just CPU first, then CUDA, then OpenCL.  So be prepared to wait a little while to use new features on your GPU if you go for the ATI card.

To be fair, OpenCL is by no means unusable, it just isn't as polished as CUDA.  I do have a friend with an R9-390 and it mostly works fine in Cycles.

In fact, here is a list of supported AMD devices as of May 2015.

With regards to your last statement about other software:

Most commercial 3D software (Autodesk included) won't really work with a gaming-class GPU at all, and definitely not an ATI card.  If you want to use that kind of software you really need a workstation-class GPU (i.e. Nvidia's Quadro cards, frankly ATI's workstation cards are a joke).

However, keep in mind here that Blender is not optimized for workstation cards.  That doesn't mean that they don't work at all in Blender, it's just that Cycles just won't be able to take advantage of the extra features you are paying for in a Quadro.

Workstation cards are also not ideal for gaming.  I do have a Quadro M4000 and it works fine for the few games I play (AoE III, Civ V, a couple old emulators, etc.), but if you are any kind of a serious gamer you definitely don't want a workstation card.


This is the solution that works for me !
Enabling High Quality Normals in Performance under the Render tab.
Thank you again!


I guess you have 2 main approaches:

The eyelids are parts of the face mesh. As Hikariztw said you'll animate them with bones or shapekeys. Not easy to do but for a realistic character it's the only solution.

The eyelids are part of the head object but they are separate meshes. You'll rig them to bones and make them go up and down, or rotate, or even just appear and disappear (move outside/inside the head mesh). It's not a realistic solution, so it's good for a cartoon character, and it will be much easier to animate.


Need tight corner, but end up getting pinched geometry!

I was able to solve the problem by copying the normal vectors of non-pinchy vertices and then pasting them to the pinchy vertices and flatten them out. I needed to do this separately for every problem vertex though. I don't know a way to do it all in one fell swoop. I tried to multi-select and paste, but it ended up breaking other normals by me trying to do too many at once.
Go into Edit Mode and select a vertex that has no pinch. Press Alt + n to bring up the Normals Menu, and then choose the Copy Vectors option. Now select a problem vertex. Go back to the same Normals menu and choose the Paste Vectors option. You may find that some trial and error is needed to ensure that you aren't making things worse, but in relatively short order, I had the smooth surface you see here.

There may be a more elegant solution. Anyway, hope this helps.


Basic fluid - inflow too small to generate fluid or generated fluid too thick

Setting your y-axis inflow to -200 is a substantially large number for fluid physics. Try something like 2 or 3, because large numbers cannot be calculated, and don't show up. This is probably why your simulation is failing.


Is there any other way to model this archway?

Sounds like a job for Proportional editing.

Set it to Sphere faloff and adjust size to your liking.


Create a Bezier Curve and place it on top of your 2 cubes like in the picture

Select the top-left corner adn press E to extrude it and place the new vertex in the top-right corner (use X or Y to keep it at the same height). To get right corners set the Properties > Object Data > Shape > Resolution Preview U to 1.

Keep extruding until you get a rectangular spiral (I did it quickly so it's not straight, but you get the point)

Create a rectangle curve (it has to be a curve, not a mesh!) by using a circle with resolution set to 1 or by using the addon Add Curve: Extra Objects (it's already inBlender, you just need to enable it in the User Preferences).
In the spiral's Properties > Object Data > Geometry > Bevel > Object insert your rectangle and enable Fill Caps

Resize your rectangle and animate the End slider

If you want your corners to be a bit rounded you can increase your Resolution Preview U, but you'll have to play quite a bit with your vetex handles


Why do my properties show up as '[string contents] not found' during debug?

I guess I'm a little idiotic for not noticing but I've found my own answer and I guess I should leave it here for future reference!

When changing a strings data the word needed to be stored inside quotation marks (e.g -  "Up") or it won't work, hope this helps someone in the future.


Can I access the render screen size in a custom filter 2D in the game engine?

All the game properties stored in the object that calls the Filter 2D are passed to the shader as uniforms. So if you have a width and a height float game properties you can set their values at run-time to match the window size.

However, be aware that the window size (which you get from render.getWindowWidth() or render.getWindowHeight()) is not the buffer size. The buffersize is the closest power of two for that dimension (e.g., a window that is 1024 x 768 will have as buffers 1024 x 1024).


Check User Preferences➜Editing➜ Undo➜ Step is not set to 0.
Try undo from dropdown menu(assume tho you have tried this alraedy)
Try restoring default key layout.


Animation nodes: bake Cycles Material Output to keyframes - possible?

After further search I think there is no node for this.
Now I did it with a quick an dirty script-node:
    # inputs:
# Enable = boolean
# SetKeyframes = boolean
# RemoveUnwanted = boolean
# MaterialName = text
# pframe = integer

import bpy

mat = None

if Enable:
    for tmat in bpy.data.materials:
        if tmat.name == MaterialName:
            mat = tmat
    if mat != None:
        print ('material found')
        emitStr = mat.node_tree.nodes['Emission'].inputs[1]
        if RemoveUnwanted:
            try:
                emitStr.keyframe_delete( 'default_value', frame=pframe)
            except:
                None
        if SetKeyframes:
            emitStr.keyframe_insert( 'default_value', frame=pframe)

    else:
        print ('material '+MaterialName+' not found')
        return


How can I make vertices on a cylinder create a circle?

You may use To Sphere operation (as @Dontwalk pointed), but Loop Tool's Circle creates much better result.

Activate the Loop Tools add on in User Preferences (Ctrl+Alt+U). Apply the transformations to the object (Ctrl+A-->Rot&Scale). Select the edges on a cylinder you want to transform to a circle and snap the cursor to it (Shift+S). Press W-->LoopTools-->Circle. Finally uncheck the Flatten checkbox in a Circle panel of a Tool Shelf (T).

You may then extrude the circle inwards as was shown in the tutorial.


Matrix from quaternion produces a different orientation

Your quaternion is not normalized, this can happen during interpolation.

Blender will still only view the quaternion as an orientation, even if it is not pure. However, the to_matrix function will convert the quaternion as it is.

To circumvent this, simply normalize the quaternion before converting it to a matrix.

ob.matrix_world = ob.rotation_quaternion.normalized().to_matrix().to_4x4()


You must have set your "Type of element to snap" to vertex or segment and have your "Snap onto Self" turned on. Check that Type of element to snap to is set to face. You can leave "Snap onto Self" on and turn on "Project Individual Elements on the surface of other objects"


Run script stored in text editor/blend file from CLI

Run blender --help and look for any option with 'Python' in the name. You'll find that it's blender filename.blend --python-text Import.

Alternatively, name your script yourscript.py (so end it in .py), and you can enable the "Register" checkbox to automatically run the script whenever you load the blend file. This can be easier, depending on your needs.


The automatic weights aren't perfect, you can manually decide what part of the mesh gets to be controlled by what bone.

It's called weight painting.

Here is a tutorial for beginners.


You can use the Pack All Into .blend function. Open the project, go to File > External Data > Pack All Into .blend, and wait for the packing of your images/textures (it depends on how many textures you used in your project). Then save again the file (maybe with a different name, e.g. project_packed). So when you open the file on a different computer, you don't have to re-loading the textures.


How do I render a specific part of the viewport?

The functionality is called Render region. Press CTRL + B and then draw a rectangle around the area you want to render.

Remove the region with CTRL + ALT + B


Python Scripting : AttributeError : 'SpaceTextEditor ' object has no attribute 'context'

I am a big advocate of avoiding bpy.ops as much as possible.  I wrote an example at http://web.purplefrog.com/~thoth/blender/python-cookbook/load-image-texture.html which might help you understand how to use python to create a material using an image texture:

Here is the most important bit:

def material_for_texture(fname):
    img = bpy.data.images.load(fname)

    tex = bpy.data.textures.new(fname, 'IMAGE')
    tex.image = img

    mat = bpy.data.materials.new(fname)
    mat.texture_slots.add()
    ts = mat.texture_slots[0]
    ts.texture = tex
    ts.texture_coords = 'ORCO'

    return mat

fname = "/var/tmp/blender/mohawk-seal0001.png"
obj = bpy.context.active_object
mat = material_for_texture(fname)
if len(obj.data.materials)<1:
    obj.data.materials.append(mat)
else:
    obj.data.materials[0] = mat


How can I snap the center of the bottom part of a box to the center of a plane?

In edit mode select bottom face of cube, Shift+S Cursor to Selected
Object mode press Shift+Ctrl+Alt+C Origin to 3D cursor
Select the plane
Shift+S Cursor to Selected
Select the cube
Shift+S Selected  to Cursor, Offset


how can i create these two similar yet somewhat different energy/light based items?

A tutorial would be beyond the scope of this website, but what I can tell you is that it largely depends on what engine you're using.

If you're using the Blender Internal renderer, you'll want to rely heavily on compositing.

If you're using the Cycles engine, you'll probably still do some compositing (for the glow) but in both cases, you'll want to work with the "Light Path" node to select which rays are actually visible in the camera. For example, if you give your crystals an emission material, then they will just look solid bright in the camera. However, if you set up a node system that doesn't show direct emission rays to the camera, then you can have the emission material cast light around the scene, but have the crystal look in the camera.

Take a look at the node setup on the SECOND answer on this question. The "Is Camera Ray" is piped into the Fac of a Mix Shader. This means that if the ray is directly visible by the camera, it will use the bottom shader and the camera will see a transparent material for that object. HOWEVER, if the ray is any OTHER kind of ray, it will use the top shader and the rest of the scene will see an emission material.

Exchange that Transparent BSDF for a really cool crystal-type material, and you'll see a crystal that casts light all over the scene.

The only problem with this setup is when the crystal is actually visible in the reflection of ANOTHER object. The emission shader will be visible in the reflection, not the crystal shader. So just be careful how you use it.

Hope that helps!


How to use API to get an object's constrained position?

After much digging around I believe for this simple case I can get what I need in D.objects['Empty'].matrix_local. E.g.

>>> D.objects['Empty'].matrix_local
Matrix(((1.0, 0.0, 0.0, -0.7031904458999634),
        (0.0, 1.0, 0.0, 0.0),
        (0.0, 0.0, 1.0, 0.29674994945526123),
        (0.0, 0.0, 0.0, 1.0)))
>>> [D.objects['Empty'].matrix_local[i][3] for i in range(3)]
[-0.7031904458999634, 0.0, 0.29674994945526123]

There is also matrix_world (which is the same in this simple case). But if there is a better way to do this more generally, I hope someone will illuminate us.


How to render specular highlights as a separate image with alpha channel?

You should add in the specular with color, not mix shaders. In that way you will get a white highlight.

Here I'm using color ramps to make a mask for transparency and removing some of the gray on the specular before adding it to a solid color.

You can also render out Diffuse and Glossy and use the Compositor to choose color.

You need to add light passes for gloss direct and diffuse direct

The new passes can be then be exported from the Compositor via Image editor (set the image to be "Viewer Node") and then saved from there Image->Save As...


Video rotated after importing it for motion tracking

Phones typically provide the rotation orientation via a hint in the wrapper metadata. Given it is a hint tag, many pieces of software will ignore it.


You need more lights.  Currently, you have one dim light.  Try creating a sun lamp, and putting it near your character.  This will make it a lot brighter.


As it turns out, blender is just fine, and the problem was in mplayer, something that or other, xv, x11 thingy... i took videos on other machines (linux and windows) and files were working just fine in full screen. So i went after mplayer, and there was this update that required restart of X11...

anyway, i am sorry i took your time, noobs like me are probably the worst kind...


After you answer in the comments, here's a simple setup:

The square root of the dot product is the distance to the center (in this case, the distance to an empty object).
Adding some value to it before the module operation will just make the colors to cycle.
Scaling the rings loop is also possible by multiplying the distance with some other value, before the add node. Values less than 1 will produce wider rings, and values bigger than 1, thinner rings.


Some vertex groups on the armature have their location offset

I hope it answers your questions:
In Edit mode you should align the bones with the lamp arms:

Also, stick the IK target head to the tail of the IK bone, otherwise, as soon as you switch to Pose mode, your IK will move away from its current position to stick to its target:


Get indices of vertices of triangulated faces in python

I waited before posting this in case a better answer came up.  Since no one posted anything, here is something.

I found the following code on http://davidejones.com.  It is definitely not 100% alright so far as OpenGL goes, but it does run so far as Blender is concerned. It may help you get started until someone who knows what they are doing shows up.

The problem I see right away, when I look at the output, is that this code is printing out all of the redundant normals and UV coords but not those of the vertices.  Since the stride of the different attributes does not match, you can't make a VBO from this code.

import bpy

obj = bpy.data.objects['Cube']
mesh = obj.data

normals = []
indices = []
for face in mesh.polygons:
    indices.append(face.vertices[0])
    indices.append(face.vertices[1])
    indices.append(face.vertices[2])
    for i in range(len(face.vertices)):
        v = mesh.vertices[face.vertices[i]]
        normals.append([v.normal[0],v.normal[1],v.normal[2]])

verts = []
for vert in mesh.vertices:
    verts.append(vert.co.xyz)

uvs = []
for uv_layer in mesh.uv_layers:
    for x in range(len(uv_layer.data)):
        uvs.append(uv_layer.data[x].uv)

print(indices)
print(verts)
print(uvs)
print(normals)


Is it possible to see an object's positions at different frames all at once?

The technique you're referring to is usually called "onion skinning" or "ghosting". An implementation that fits your needs exists for Armatures and Grease Pencil.
Other kinds of animations don't have an equally good implementation of this: objects' midpoints can be "ghosted" for rigid motion (but this ignores rotation/scale and requires constant updates of your cache), while very little is present (as far as I know) for "soft", shape-deforming, motion.
Here you go:
Armature
If your object is driven by an armature, then it's possible to enable ghosting from the Object Data properties panel of the armature:

Just increase the "range" option under Ghost.
Grease Pencil
Onion skinning is also available for the Grease Pencil as a "Layers" setting. The options are in the "N menu" in the 3D viewport:

Rigid motion
For keyframed objects or rigid bodies, you can display the trajectory of their origin points using "Motion Paths". These paths must however be updated every time you change something (it's fast, but requires a click and can be distracting). I couldn't find a way to also "ghost" the orientation/shape.

[ Just a word on dupliframes: alternatively, it's possible to switch the object's duplication object, from the same property panel, from "none" to "frame": this will display all the frames in the same way as the current one (no transparency, no customisation), and must be switched back to "none" as soon as you're done animating. Please note that this is not a visualisation tool made for the purpose of ghosting, but a technique for instancing, that is supposed to be used at render time as well! ]
Particles and Point cache simulations (soft body + cloth)
(Just to make a complete review I'll add this, even if it's not related to your question)
For particle and "soft" simulations, after baking, the trajectories of the particles or of the vertices can be shown in Particle Edit mode and tweaked with the "Draw: Path Steps" and "Fade Time", "Fade Time: Frames" options.


How to prevent a cloth from entering another mesh?

Blender cloth sim are perfect for dropping tablecloths onto tables, they rarely work well for shirts (although they will work for skirts).

That said, if you have it working, more or less, here are some tips for better shirt sims:

Under collision, enable Self Collision, this will try and help with the cloth hitting itself.
Lower all the distance settings way down, including collision.
Your shirt mesh density and topology will have a huge impact. In general, an all quad mesh with nice flowing loops works best. There is a sweet spot in terms of mesh density, ballpark for a shirt the arm loops should have 8-12 vertices. Any more and the sim may tend to crumble.
Sometimes you want subsurf above the sim and sometimes below it, for low poly shirts you want it above.  And make sure the viewport/render levels are the same.

For convincing shirt stretches, you usually apply the simple sim, and use multi-res sculpting for the folds.


How to increase the number of faces in a model

It's hard to know how to help without many details. If you're following a modelling tutorial and you're supposed to have 32 faces and you only have 11, you may want to go back and double check you followed the tutorial properly.

But your question was how to increase the number of faces, and here's a few ways how...

Method 1: Using Subdivide Tool

Select your object and make sure you are in edit mode.

Click this button to enter face select mode:

Select the faces that you wish to divide by right clicking on them:

Press W, and when this menu pops up, click Subdivide:

You can repeat this as many times as you want. Each time the selected faces will be divided into 4 new faces if they are quads.

Method 2: Using Knife Tool

Again, select your object and make sure you're in edit mode:

Press K to activate the knife tool. Now you can draw lines where you want to cut your object:

And press ENTER when you are satisfied, or ESC to cancel.

Method 3: Ring Cut Tool

This is essentially a much more controlled, but limited, version of the knife tool. Once again make sure you select your object and are in edit mode. Press CTRL + R to activate the ring cut tool, and mouse over an edge. The purple line is where the cut will be made.

You can scroll up and down with your mouse to increase/decrease the number of cuts, and click to perform the cut.

At this point you can adjust the position of the cuts, or right click to keep them in the center.

Method 4: Subdivision Surface Modifier

This one is a little different. This time, make sure you are in object mode:

With your object select, go to the modifiers panel on the right (it looks like a wrench) and click Add Modifier and select Subdivision Surface.

You can adjust the number of cuts with the numbers where it says "View" and "Render". If you don't want your object to be rounded, click on Simple. Click Apply when you are satisfied.


Render Freestyle strokes behind objects with alpha transparency?

Yes, you can do this easily from the Freestyle settings. Blender/Freestyle gives you a lot of control. The parameter you want to change is QI Range. This specifies a range of face occlusion to render strokes for. So if you have a cube like in the example below you would set the range Start at 1, and End at 1 or higher and that would render strokes for the edges of the back of the cube.

However if you had a second cube behind your first one, a range of Start:1~End:1 will cause the second cube not to have strokes rendered in the areas which are occluded by the foreground cube. Here is an example:

And if we up the values to Start:2~End:2 the foreground cube's back edges are not rendered but the front edges of the background cube are:

Here is your scene rendered with values of Start:1~End:100 and Alpha set to 0.5 for the occluded stroke set:

Here is the .blend: http://www.pasteall.org/blend/31648

And finally, here is the section of the Blender manual which explains this if you want to read further: https://www.blender.org/manual/render/freestyle/parameter_editor/line_set.html


Have problems with the Blender Eve character. Can only modifie one side of the character in sculpt mode

I found the answer. It has something to do with the Shape Keys. You have to select basic and then go into sculpt mode .


How change the Pie Menu Radius with python?

And similar can be done for all other items on the User-Preferences -> Interface tab. (Warning doesn't update the visible value on the UI until you move your mouse, or trigger ui redraw some other way)

import bpy
prefs = bpy.context.user_preferences
prefs.view.pie_menu_radius = 80


Although it's a drastic measure, you could erase the %APPDATA%\Blender Foundation\Blender directory. That'll make you loose all your settings (and possibly extra addons you installed), but also should reset any lingering references to the old installation directory.

Make sure you create a backup copy before doing this, though.


Is there a way to allocate more memory to GPU for the GPU Compute

Your computer already do this automatically. VRAM is only storing very frequently-used resources that need to be accessed in a very short amount of time. If/when the VRAM is used up, most computers will attempt to transfer some of the less important information your your RAM.

DirectX, AGP and PCI-Express cards do this automatically.

You could manually assign more RAM to be used exclusively by your GPU, but this requires a lot of internal knowledge about computers and you have to know exactly what you're doing, because you can really mess up your computer this way. I won't add links to any tools that can do this, because there are always people stupid enough to attempt this without proper knowledge (Not saying you are, but there are bound to be someone in the future at least).

If you really want to do this manually, research it until you can feel comfortable messing with the RAM, an find the tools yourself. I don't want to be responsible for you frying your RAM cards.

If you do not have the proper knowledge about how to do this (which very few computer users do), you're better off inserting/buying a new GPU with more VRAM.

If you're on a laptop, chances are that your internal GPU uses some of your RAM if it runs out of VRAM. If this is the case, you should upgrade your laptop's RAM capacity.

Final note

RAM is a lot slower than VRAM, so you'll notice some real slowdowns in the rendering times. Also, again, do not attempt manually assigning RAM to your GPU without proper knowledge about this.

Hope this helps.


BMesh edges have a seam property.

You can:

import bpy
import bmesh

mesh = bpy.context.object.data

bm = bmesh.new()
bm.from_mesh(mesh)

bm.edges.ensure_lookup_table()

bm.edges[0].seam = True

bm.to_mesh(mesh)


Why does changing the values of a shape key affect the whole model?

Probably you separated the humanoid by material or something and then finalised.  You'll have to start all over again, finalise and then separate. Should work. Happened to me once.


it's possible to save materials in cycles node editor to reuse them in other project?

You can create a .blend file that is a master collection of your finished materials, and then Link (not Append) this to your various other .blends.

Be cautious with this kind of workflow though, because if you change anything in this master file it means your materials in all other .blends may render differently - so for example, re-rendered frames of animation may look different.

It's generally best to work with Linked files on a project basis, not a global basis.


How to duplicate an object with random start frame?

duplicate your character (shift+D) then right click to keep it in the same place above your original character

then shift the new duplicated character by changing the value of delta location/rotation/scale (object tab > delta transform)

now you have two distinct objects moving together, you can shift the keyframes of the second object in the dope sheet editor (b to box select all keyframes then g to move them)

now you have two objects with two shifted animations.


Weight painting gives a strength value to a vertex or to some vertices, it determines the level of influence a group has on this vertex or on those vertices. If there is no vertex it can't paint.

You say that it paints through the object. Maybe you've given your object a Solidify modifier (is it what you mean when you talk about Solidary)? In that case apply the modifier. The other possibility is that you've enabled the 2D Falloff option, deactivate it in the N panel > Tool > Brush > Options.

You don't say anything about these sprinkles and you don't explain what you mean by "passing through the box"... If they are Particles > Hair objects and if you want them to appear only on some parts of the box you need to create a vertex group and select it in the Particles panel > Vertex Groups > Density. If they are Particles > Emitter, maybe you need to choose Faces instead of Volume in the Particles panel > Emission > Source > Emit From.


The plant is a class attribute and not an instance attribute, meaning that each instance of the class ImportPlant references the same plant. Therefore your script should use ImportPlant.plant instead of self.plant.


This is very similar to the thin glass problem.
It can be fixed by giving it a thickness, (i.e. Solidify Modifier, as already sugested), which in some cases raises some topology problems, besides the doubled mesh.
Or by faking the surface thickness by not using refraction at all.
This last approach raises another problem: IOR inverts automatically on backside faces (which in this case should be treaten as frontside)... Luckly we can solve that.

Explanation:

When a light ray hits a surface with a refraction shader, the ray will be bent dued to the difference of the light speed from one side of the surface to the other. This speed difference is represented by the IOR and ruled by the Snell's law. When the ray is exiting that medium, the difference of the light speed gets inverted, and so the IOR. Cycles does this automatically, and treats objects as solid (not hollow).

If we want hollow objects, we need to model both outer and inner surfaces of that object, and most of the times is exactly what we do. But there's a nice particularity from this phenomena: if both surfaces are parallel (at least where the ray enters and exits), the outgoing direction will be the same as the incoming direction; and thought the complete light path is not a straight line, the difference is quite small, sometimes smaller than the pixel size, and we can discard all that refraction calculation. A very good example of this are glass windows. In 3D, we call this the 'Thin Wall' or 'Thin Glass' effect, and some renders even have a shader just for this purpose.

In Cycles we can do something similar (treat the surface as a thin wall and discard refractions), but we need to specifically tell the engine that the IOR from a face when viewed from the objects inside, is the same as from the outside.

The nodes in the 'Fixed Backside IOR' frame do exactly that: If 'Backside' is 0 (False), we get (1-0)*IOR+(0*1/IOR)=IOR; if it's 1 (True) then (1-1)*IOR+(1*1/IOR)=1/IOR. Cycles will invert this backface value internally and in the end it stays equal to the initial IOR.

After having the IOR fixed, we can deal with the Reflective/Transmissive sides of the Fresnel formula. I didn't use a complete transparent shader for the transmissive part, because the greater the angle between the incoming ray and the surface normal, the greater the distortion and absorbtion on the light on that path. I used the translucent shader to mimic that effect, but it's just an approximation.


Scripting: Converting Text object to Mesh object fails due to incorrect context (2.78)

bpy.ops.wm.read_homefile() - kills your current file and causes the trouble. If you could avoid it, it will work. I think you can import a scene from some blend file instead.
Look also this thread, and this.


Why does the collada exporter not export texture references?

Start with the default cube. Ensure you've created a material or use the default material already created. Assign a texture to it as a diffuse image, say "lava.png". The important point here is to assign your object texture via a material. There is another way to directly texture mesh faces without a material but you still need a default material to get the Collada export to recognise textures, so I suggest going with this approach. If you export as Collada format now, ensure you select "Include material textures" checkbox in the export options. This will produce something along the lines of following XML element in the export file:

<library_images>
    <image id="lava_png" name="lava_png">
        <init_from>lava.png</init_from>
    </image>
</library_images>

But the library effect element will look something like:

<library_effects>
    <effect id="Material-effect">
        <profile_COMMON>
            <technique sid="common">
                <phong>
                    <emission>
                        <color sid="emission">0 0 0 1</color>
                    </emission>
                    <ambient>
                        <color sid="ambient">0 0 0 1</color>
                        </ambient>
                    <diffuse>
                        <color sid="diffuse">0.64 0.64 0.64 1</color>
                    </diffuse>
                    <specular>
                        <color sid="specular">0.5 0.5 0.5 1</color>
                    </specular>
                    <shininess>
                        <float sid="shininess">50</float>
                    </shininess>
                    <index_of_refraction>
                        <float sid="index_of_refraction">1</float>
                    </index_of_refraction>
                </phong>
            </technique>
        <extra>
            <technique profile="GOOGLEEARTH">
                <double_sided>1</double_sided>
            </technique>
        </extra>
        </profile_COMMON>
        <extra>
            <technique profile="MAX3D"><double_sided>1</double_sided>
            </technique>
        </extra>
    </effect>
</library_effects>

Note that the diffuse element defines a colour rather than an image reference. This means there's no 'link' in the Collada file between the lava.png and the diffuse component of the material associated with the mesh.

The missing step relates to the coordinate mapping technique used. Go to the texture panel for the lava.png and find the "Mapping" section. The coordinates entry is likely set to "generated". Change this to UV and export again with "Include material textures" and the diffuse entry will now reference "lava_png-sampler".
Something like:

<library_effects>
    <effect id="Material-effect">
        <profile_COMMON>
            <newparam sid="lava_png-surface">
                <surface type="2D">
                    <init_from>lava_png</init_from>
                </surface>
            </newparam>
            <newparam sid="lava_png-sampler">
                <sampler2D>
                    <source>lava_png-surface</source>
                </sampler2D>
            </newparam>
            <technique sid="common">
                <phong>
                    <emission>
                        <color sid="emission">0 0 0 1</color>
                    </emission>
                    <ambient>
                         <color sid="ambient">0 0 0 1</color>
                    </ambient>
                    <diffuse>
                        <texture texture="lava_png-sampler"/>
                    </diffuse>
                    <specular>
                        <color sid="specular">0.5 0.5 0.5 1</color>
                    </specular>
                    <shininess>
                        <float sid="shininess">50</float>
                    </shininess>
                    <index_of_refraction>
                        <float sid="index_of_refraction">1</float>
                    </index_of_refraction>
                </phong>
            </technique>
            <extra>
                <technique profile="GOOGLEEARTH">
                    <double_sided>1</double_sided>
                </technique>
            </extra>
        </profile_COMMON>
        <extra>
            <technique profile="MAX3D"><double_sided>1</double_sided>
            </technique>
        </extra>
    </effect>
</library_effects>

This should then import, with the texture intact, into whatever you're using, e.g. Assimp or a modelling package/viewer.

Hope this helps.


Anvil from Guru blender not exporting with all materials and textures to glb file for WebGL

glTF 2.0 has a specific PBR material model, for transfer to realtime rendering engines.  It cannot support arbitrary arrangements of Blender nodes, as WebGL wouldn't be able to handle realtime rendering of arbitrarily complex Blender nodes.  Instead, the glTF material definition has a strict number of fields, corresponding to a particular interpretation of physically-based materials.
The Blender Manual documents how to export materials to glTF.  The short version is, you'll need to adapt your material node setup to use primarily images connected to the Principled BSDF node.


How do I mirror across anything other than X, Y, or Z axis?

Use two mirror modifiers, both one along the X+Y axis.
Once you have the Y and X mirrored once, then you can add an empty and use it as a mirror object to mirror it along the x+y for your second modifier.

Simply position the empty to where you want to objects to be mirrored. The empty will essentially replace the object's origin for the mirror modifier.


How can I make Blender to exit with the same exit code as the python expression?

You will have to put the expr in try and explicitly exit with an error code on exception.

E.g. following exits with exit code 10 (user defined):

"\Program Files\blender foundation\blender\blender.exe" --background --python-expr "exec('import sys\ntry: 2/0\nexcept: sys.exit(10)')"


You need to copy the material.

To do this, select all the cubes.
Next also select the cube with the texture(be sure to do that one last). The cube with the textures should have a light orange background instead of a dark orange.
Finally press Ctrl-L->Materials.
To copy the UV unwrap, use Ctrl-L->Transfer UV maps

Done!


How can I rotate particle instances on the X axis?

If you want to make the particles stand up and rotate on the Z axis, choose Orientation Axis > Global Z, as the object is probably not oriented the way you want on the surface, select the original object, go in Edit mode and rotate it correctly. Now play with the Rotation > Random Phase value.
Edit: Your question is not clear, either you want to vary the orientation axis, or you want to keep the same orientation but change the rotation values. For case #1, use the Randomize value, for case #2, use the Randomize Phase value:


How do I push a crease in to make this mesh more "smooth?"

I suspect your topology might not be the best for this kind of object. Without suggesting mine is the best, or perfectly suits your purposes, here's a way of modelling it.

Starting with a half-cylinder, with loop-cuts as shown
Use the knife tool (K), cut a diagonal from the 2nd-bottom longitude to the 2nd-top longitude just inside the existing loops, and then extend the diagonal to the boundaries,  using the knife tool again, this time constraining it. (KC)
X Delete the inside faces, and ensuring the pivot is set on the center-line (see the last item) SY, scale the center section out appropriately
CtrlE, from the Edge Menu, 'Bridge Edge loops' having selected the loops on the sides of the gap.
CtrlR cut in some more holding loops .. (pressing E makes the new loop parallel to one side or the other, and pressing F flips which side)
Assign a Mirror modifier, and maybe a Subdivision modifier..

By using GG to slide edge-loops (with E and Fin the same way as when you made them,) you can tighten or loosen the creases between the sections by moving the holding loops in or out, or you can even get rid of the central loops. If you want to completely soften the creases, careful use of AltS to scale vertices out along their own normals, and CtrlV Vertex Menu > 'Smooth Vertex' will get you there, but that's destructive, so save snapshots.

This result may not be precisely what you want, but variations on this sort of approach may work for you

Here's a contrasting example, where the central loop in the crease has been removed, and its outside loops slid outwards, to soften the transition:


You can use the Exclude Layer to remove a corresponding silhouette


Architectural Addon - Export UV for handcraft paper models

Jachym Michal solved this issue. Its the "Export Paper Model" addon, preinstalled in blender. Thank you again!


If you have a nice computer, look into smoke simulation

Although, any flames that you make in space are going to look a little bit fake, because most people have never seen flames in space

Ignoring the awful camera quality, https://www.youtube.com/watch?v=FEom0G30Gic is the type of thing that it seems like you are trying to emulate. If you want realism, I would do a quick fire thing like you have, and then overexpose the video while the fire takes up most of the screen.
Your also missing the camera shake from the rocket, your footage is unnaturally smooth.


Thanks for the answer! Solved by using UV > Smart UV Project that create an automatic seams, it is perfect method for this object.


Why can't I see wieght colors unless I use the numpad [ / ] key?

You can barely see weight paint colors while in the Material shading mode if the shape is not in Local View, you have to switch shading mode to Solid.

I was going to delete this post but others have asked before why they can't see weight paint colors.


The MakeHuman tab is in the viewport list as @ChristopherBennett says.
For my instance of 2.83.4 the key shortcuts did not work, but the list can be opened by clicking the little arrow near the top right of the viewport (shown below).


How can I apply some material included in a node-pack library?

Those are Node groups. Node groups are node setups can take input to give an output with which you can use in other nodes. (Think of it like making a new node of many nodes put together, similar to a function in computer programming.) This also allows you to create a node setup then use it in many places.
The collection of node groups you linked to is made up of Shader nodes and Compositing nodes. The author of the collection you linked to also explains the function of each node group here.
Adding a node group to your blendfile:
You can use them in your own file Appending them. You can do this by pressing ShiftF1> append, then navigating to the blendfile with the nodegroups which you want to use:

Pick the type of data to append, in this case we want Node groups so pick NodeTree:

Select the node group you want to import into your file:

See this question for more information on appending and linking.
You can now add this node group to your own node tree.
In the Node editor, press ShiftA> Add node > Group and select the appended node group:

You now have a new "node" which you can use in your node tree the same way you would use any normal node:

In the case of this node group, it supplies a Shader output, however some node groups return a value or an image (or a vector, or even multiple different outputs).
Editing node groups:

You can edit the nodes in a node group by selecting it and pressing Tab.

You can edit, add and remove inputs and outputs of the node group in the Properties region (N):

You can have node groups inside node groups, so to go to the parent group (the node tree in which the currently active group is located) press the  button on the header. (you can think of this behavior as a file tree with the base node editor as root)

You can ungroup nodes by selecting the group node and pressing AltG. This will place all the nodes in that node group in the current node tree. (I.e. the currently open group or the base node editor)

Other things to note:
The way node groups look and function changed a lot in 2.67. See the wiki for a full description of the changes


This creates instances of the group, it works by first adding an Empty, and setting its .dupli_type and .dupli_group attributes. I believe for all intents this is functionally equivalent to a group instance.

import bpy

scene = bpy.context.scene

group = bpy.data.groups['CubeGroup']
instance = bpy.data.objects.new('dupli_group', None)
instance.dupli_type = 'GROUP'
instance.dupli_group = group
scene.objects.link(instance)

(credit to: blenderartists.org user Atom)

For completeness, this is how to create groups via the API. This expects the name (string) of a group, and will add any objects in the objs collection to this group.

def to_group(named, objs):
    '''
    named:   (string) name of group to use, or to create if not present
    objs:    a collection of object references
    '''
    groups = bpy.data.groups

    # alias existing group, or generate new group and alias that
    group = groups.get(named, groups.new(named))

    for obj in objs:
        if obj.name not in group.objects:
            group.objects.link(obj)


Render what camera sees and not first frame

No need to scrub every time from the beginning. You can adjust the range of frames to start rendering (and playing) from however you want. Look in the Properties Panel for the Output Settings tab, and adjust the range for the frames you want rendered. Your file is likely starting from the beginning because the start frame is 1 by default. Change this setting to something later in the timeline.

You can alternatively change this same range setting in the Timeline Editor window, which can be found at the bottom of the screen while using the Animation Workspace. Changing it in either location changes it in the other.


How can I learn basic anatomy/proportions good enough to where I can sculpt a basic head from scratch

I've found that when starting out modeling a head, it's helpful to insert a background image and simply draw the head by extruding a vertex around it. Then you can add depth to the head and make it look realistic. These two videos got me started with the basics of modeling a head from scratch.

https://www.youtube.com/watch?v=ifFD8iD976g

https://www.youtube.com/watch?v=3LwQO_tWTAQ

To add a reference image to model from, first press numpad 1 to go to front view. If the view isn't already orthographic, press numpad 5 to switch to orthographic. Then, press the N key to open the right toolbar, and scroll down to "Background Images". Check the box, then expand the menu and click Add Image. Set the Axis as "Front", then click Open to open the image you want to use. Do the same thing for the left, right, and back views, but make sure the image you use for those views is truly of that part of the head. For example, make sure from the left orthographic view you can see the image of the left side of the head. Once the image is added, you can change the opacity of it with the slide under the background image menu.

Hope this helps!


How bake cycles material to PBR texture in 2.80?

Baking in Blender
Baking in Blender means baking the lighting information to texture maps, not the properties of the Principled shaders like roughness. You can bake AO and normals, but as far as I know, currently Blender Cycles only bakes normals from geometry and combining bump maps into a normal map or a few normal maps into one will not work correctly.
Buzzwords do not mean much
Buzzwords like 'PBR texture' or 'PBR baking' do not change the fact that this is nothing more than a process of making texture maps for a material. 'PBR' may only indicate that the values in the texture maps are scene referred(realistic reflectance values), that's all.
Baking textures created in material node tree as emission
So I believe your goal should simply be to make textures for your material in Unity.
You can experiment and see preview of the material in Blender using Principled BSDF. It will be easier if you work with only one Principled BSDF node and combine/edit the needed textures for it's properties. Whatever textures you combine or edit in the node tree of the material can be connected to an emission shader and baked out as emission:

You would just take the output of the last node just before it goes into some property of Principled BSDF shader(like for example Roughness) and connect it to an Emission shader and bake it. This is how you would make a single texture out of everything that you combine together in the node tree for that property.
You probably do not want the values to go through any color management transforms, so you can turn color management off during this process:

Baking ambient occlusion might also be useful, but it depends on how you want to set up the shaders in Unity. It can be made into a separate map, or mixed  into other maps depending on the situation.
Bump maps can simply be mixed together(added, multiplied, overlayed or mixed any other way that produces a desired height map).
Nothing normal about normals
If you needed to combine a few normal maps on top of each other, that is a lot more complicated than it may seem - see this answer for more info.


Re-Centering the Camera view after Shift Drag?

The only option I know of is to select the camera in question and then press Home before repeating Shift+Numpad Enter

Pressing Home with the camera selected runs the 'View All' command and will bring the camera back in view and centred but it will also adjust the zoom so that all the camera is visible, possibly loosing the 1:1 ratio. So it would be necessary to repeat the 1:1 view shortcut afterwards.


Why are there dark shadows on model in edit view?

Your normals appear to be flipped. That dark shading is the back side of the face, also known as the Backfacing.

To check if this is the problem, open the N panel in edit mode, go to the Mesh Display Tab, and check the box for Display Face Normals. This will make a line from the center of the face that points in the direction the normal is facing.

If this does turn out to be the problem, you can recalculate or flip the normals of a selected face by using the Recalculate or Flip Directions command under the Shading/UVs tab in the T panel.


Can't see camera's 'passepartout' / overlay around the camera's view

Thanks to Leander, I discovered it was offscreen.  I used to scroll wheel to scroll out (way, way out), and there it was.


What are alternative methods to Fluid for making a glass appear to be full of liquid?

One way is by simply creating a face for the surface of the liquid, and then use separate materials on each interface as in this post.


Shortcut for "disable object in the viewport" (DOV) Blender 2.8

I know your question was asked many months ago, but in case you never found an answer, you can assign a shortcut for 'Disable In Viewports' by rightclicking the 'Disable In Viewports' icon in the outliner and clicking the 'Assign Shortcut' submenu

1 enable DIV icon in outliner

2 rightclick DIV to assign shortcut


Start with a plane subdivide it for an uneven number e.g. 11 to have it symmetric around the center vertex.

In Edit Mode / vertex select enable propotional editing O and set the falloff.

Add a grid texture (included in attached .blend) and add a subsurf modifier to make it smooth:


Dividing a model by intersecting geometry parts

The new Intersect Tool added in 2.72 will cut up intersecting faces - this is for meshes that are part of the same object, not multiple intersecting objects and can be found in Mesh->Face->Intersect.

Campbell explains it in this video

There are a couple of addons that can help with boolean operations.

One is Blender sculpt tools - the name is a bit misleading as it also works outside of sculpt mode.

Another is BoolTool


Subdivision Surface Modifier gives unwanted results

It seems like you have applied the Boolean Modifier. Try not to do that before applying the Subsurf Modifier.

You can use the Bevel Shader for additional smoothing.


How to Properly Import from Blender to Unreal 4?

This is just a warning, not an error. It's usually the case when UVs aren't unwrapped well; either there are overlapping UVs, or some UV's are backward. It will still work, and I haven't noticed any problems with shading or texturing on the models I've imported into Unreal.
There is apparently a way to get Unreal to correct some of these problems for you.
From the Unreal forums:

Double click onto your static mesh in the UE4 -> Select the recompute tangents/normals and click save


Empties not fully processing in node tree

Found a workaround.  I just needed to put in an execution trigger that moved an object based on the frame. It's a little hacky but it gets the desired result.


What to choose GPU or CPU , and should I use opencl, Linux (openSUSE)?

Long story short. Until Vulkan is implemented in Blender (which is going to be soon from what I hear) you can use OpenCL

Yes using OpenCL will reduce your render times significantly compared to when you have set it to 'None'.

But since 570x is not that fast compared to 2600X CPU, it comes down to very specific situations where you will have advantage in using GPU over CPU (while in other cases it would be opposite). It won't be as vast as in my case, as I have a pretty old CPU.

Using a rough estimate, you would get better results using CPU in cycles (an additional setting, not present in eevee), but make sure to set the tile size accordingly in Performance Submenu In Render Settings (right side on blender, not in preferences menu). A tile size of 128 or 256 or 512 is ideal for GPU (render something on each setting to test), and 16 or 32 is ideal for CPU.

Somethings only use CPU, like the cloth simulations.

Also Blender allows you to use CPU & GPU together where possible. Just click the box in front of both CPU and GPU, like in my following screenshot.

Also, most of the blender devs use Linux, various flavors, so Linux is strongly supported. You can even get bleeding edge Alphas from builder.blender.org

Note that Blender would not raise or cause any errors based on what you are using CPU or GPU. You have to test it by doing different renders or better yet running the benchmark (BMW scene only .. or the comprehensive 5-7 scenes)

In my experience, for a beginner, you are better off just using the settings I showed below, and use eevee without worries.

Having installed ROCM recently myself on a seperate system (Ubuntu used for some unrelated testing).. I don't think you need AMD ROCM.But rather the drivers downloaded from AMD website (they released Linux drivers, that include OpenCL support), or alternatively try installing the xf86-video-amdgpu if you are using XORG


Is There A Difference In What Render Engine I Use For Exporting Edited Videos Or Frames To Videos?

The choice of the render engine has no impact on the video export. Video rendering has nothing to do with the rendering of a 3D scene.


Why can't I punch a hole through a mesh?

Booleans are not always reliable when modelling. Even when your Boolean and booleaned mesh both have almost the same mesh densities, problems always show up.

I applied the solidify modifier on your mesh and then changed the Boolean method to carve rather than bmesh. Although it could've worked if you put the Boolean modifier before the solidify, but in your case it doesn't work.

To make this work you have apply the solidify modifier and then change the boolean method to carve. If you don't want the internal faces to have the red material, change the material of the cutter mesh to the material of the mesh being booleaned.

The Blend file:


How do i add a certain amount of objects without lowering the frame rate?

There are many factors that determine frame rate.

Computer...Particles...

The complexity of the scene is one such and probably the reason why you are losing frames.

You can check the simplify box, but I for one wouldn't rely on that, it may help but not by much.

You can view everything in wireframe.

Another method is to use proxy characters in place of the 'final' characters.

Another method, that I use is to not use the in-blender time to base your animation judgment, instead take a video of yourself doing said action and place it in the bg, you can use that as your basis of time, action and reaction if you so require.

A good addon to said methods would to be to render the animation at a low resolution opengl render (after you had done...) that way you can check that the animation is too your liking without waiting for the long render times.


The size of your import is very small.
You can use the S  key to scale the object.


How to apply multiple image textures and bake them into 1 image

Probably this is what you need to start
Move to the minute  00:09:29

https://www.youtube.com/watch?v=ZMbc2e_SN_Y&feature=youtu.be

Hope that helps.

Good Luck


You can set the Display Mode for the actual rendering in the User Prefrences > Interface Editors > Temporary Windows. If you'd like to get the old behavior back, set 'Render in' to 'Image Editor' or 'Keep User Interface' and save a new start-up file.


How to perform basic tasks in Cycles vs. Blender Internal?

Introduction to Nodes

Well, you can have all sort of nodes, mostly it's quite strait forward what the node does, for an instance the Transparency node or the diffuse, glass, glossy or emission node. Depending on what you want to make you might want to Mix two nodes, for that you would use a Mix Shader node or an Add Shader node, the difference is that the Mix Shader node has a more controll over the Factor that the two nodes are displayed. I'll give some examples of how you can do basic things with nodes.

Giving material an Image Texture

To give a material an Image Texture you would create a Diffuse Node then connect to it the Image Texture Node and plug the Diffuse Node in to the Surface slot in the Material Output Node.

Giving material a normal map

There are couple of ways that you can give your material a Normal Map but a common one would be by simply connecting a Normal Map node into the Normal slot  of the Diffuse Node, also for Normal Map to work properly you have to plug into the Color slot of the Normal Map node another Image Texture Node, this Image Texture would be your Normal Map.

Adding Decals to your material

Adding Decals to your model is slightly more difficult, to add a Decal to your material you would need to connect MixRGB Node into the Diffuse Node, then you will have to connect your Base Texture into the bottom slot and the Decal Image Texture into the upper slot of the MixRGB and finally use the Alpha value as the factor for them both, just like so:


Is it possible to recover deleted files in the file browser?

No.
Sorry :/
Blender only really has mechanisms for recovering blendfiles.
But wait..
Deleting files is likely fast because usually files are deleted by flipping a single bit which indicates to the operating system that this space is now available for use. The data is still there, but the longer you use the system the more likely it is some other program will overwrite it.
If you can, unmount/eject the drive until you can mount it read-only. If the disk in question is the one the OS is on, shut down the system and use a livecd (or an OS on another disk) to mount it (read-only, of course).
It's probable that can you can at least recover some of the files (possibly all) using conventional undelete methods such as photorec. How exactly to do this will depend on the format of filesystem your drive has, among other things. I recommend searching around for instructions for your specific operating system/filesystem.
Good luck!


One way si to build both worlds inside one scene.
And then fake an 'infinitely deep' wall between them.

Build one set (I used an HDRI)
Add a wall with a 'portal' cutout.
Add a texture to this wall (I used stars) and use Texture Coordinate node > Window to map it.
The texture will always be facing towards you, faking an infinitely deep space.

Since both worlds are actually inside one scene, you can freely move objects between them.

I'm not rotating the portal, I'm moving the camera.


What causes Assertion Error during EXPORT of glTF

I tried using Export to Extended glTF 2.0 (glb/gltf) for MSFS and that completes succesfully so my work is complete.
I did also try exporting to obj and also fbx which works ok so I am assuming it is a bug when attempting to export to a 'normal' glTF.


How do I prevent VSE strips using Image Offset from being cropped before the transform effect can shrink them onto the screen?

Consider a preprocessing pass where you just create new Scaled images at the intended final size with a possible transparent border.
Suppose the Blend User had 100 images at dimension (X,Y) where for example (X = 1280, Y=800) and their final render size was .5 times (X,Y). The User might just create a [2nd new] VSE scene to quickly create a new sequence of images at the new size for final use. VSE is used to batch scale images into a new file. GIMP might do the same.
I might even place the images in the upper right hand corner and leave a transparent border in PNG format. Suit borders to your needs.  Your already use overlays. Thus no further scaling need take place because of a transparent border.  Then many or all of the files would have the same size ... the offset would be different.
Since I cannot see your VSE strips I am not addressing them directly.  So we cant see limitations, if any, of the strip manipulations. They may be some more space efficencies possible if all that were known, yet its not a requirement.
I have not considered file names.
One could claim their is some waste of hard disk space or RAM.  Space may be cheaper than time.


This is how Smart UV Project looks like.
I never checked the donut tutorial, so I don't know what's the base mesh you worked with, but when you start with blenders base mesh Torus object, it gives you nicely unwrapped UVmap into square already.

Basically to get more control over Unwrapping, you have to

Mark Seams Ctrl+E to let blender know where to split a net
(the edges marked by red color in screen, just select two edge loops with Alt+Shift select)

select all faces and Unwrap U > Reset
select only one face and Unwrap U > Follow Active Quads


How to set up accuracy of edge length overlay?

While it is not possible to increase the precision of the "Edge Length" overlay (as far as i know and after searching), there is a way to have a precise value displayed, BUT it's not "as easy" available and intuitive as activating the edge length.

What you may want to try is the "MeasureIT"-addon which comes with Blender.

It allows you to create a dynamic measurements.
I use Segment most the time to show the distance between 2 vertices (picture below).

As shown, the precision is set to 4 decimals after the point.

Expanding the shown measurement shows this:

Here you can deactivate it, change the color, size of the text, distance from object and many more things. Best to test and play around with to get the feel.

I hope it helps for your situation.


For the moment you can't bevel the edge because you have an inner face, the edge is common to 3 faces and therefore Blender can't guess how to bevel, once the inner face deleted, Ctrl B should work:

If you have a problem of shortcut, you can open the Preferences > Keymap and type "bevel" in the search field, then redefine the shortcuts you want for this operation.


What is the correct way to texture a cave for a game engine

Depending on what kind of game engine you are using

big objects like a cave are consider terrain as i know

so your best solution here is to sculpt and material paint the cave in the game engine

but you can split the cave into smaller objects and work with them

I have seen this used ..even if it give bad lighting results


What is this flicker I get while tracking a camera?

You can clearly see the tracker shifting on the video posted on the question, and it happens at the moment where the reconstruction fails.
Successful reconstruction can only be achieved with accurate tracking
You should aim to have a solve error of less than 0.3 pixels.
There are plenty of tools to help you get more accurate tracking.
Read:
Solve error high with good track?
Motion Tracking. What do the graphs represent and how are they useful?
Does the motion tracker follow a point if it changes colour throughout the video?

For a comprehensive post on motion tracking tips read
How can I get better results when doing camera motion tracking?


Floor tiles material - match size for multiple rooms in house

For a floor material, there's no need to use UVs.

Use the position vector on the geometery node to get an even (world space) mapping for the floor. You can then just use box mapping and adjust the scale in the material. It will be applied at the same global scale regardless of individual object rotations or scale.

It will also be 'stuck' to global position so moving the floor will result in the texture sliding across the surface. If that isn't desired you can apply scale and use the object vector.


Some Particle Systems glitching for unknown reason only in render

I can't reproduce your issue ... so I would say for two reasons

Enable Output Properties > Output > Image Sequence > Overwrite
or try under Particles Properties > Cache > Delete All Bakes and Bake All Dynamics again


Need a way to do a "loop cut" on a triangle fan

One way is to use vertex bevel (⎈ Ctrl⇧ ShiftB):

Once the triangle fan is converted to quads you can add loopcuts. In the gif I converted the ngon resulting from the bevel to a triangle fan with Poke (⎇ AltP).

As an alternative to bevel, you might also try Inset (I):


From your question it seems you use 3D manipulator to translate objects. In this case make sure proper mode of manipulator is checked - arrow as its icon for translating. You can choose multiple manipulators by clicking on icons with Shift.


Which features are not supported when GPU rendering?

Unless I misunderstand what you are looking for, the Blender manual seems to have a pretty thorough list of supported features per device.

As of current Blender 2.78, this list includes all supported computing hardware types, like CPU, GPU, OpenCL, or CUDA; and the available , experimental, and unsupported features for each of them, like motion blur, hair, volume, smoke/fire, subsurface scattering (SSS), Open Shading Language (OSL), CMJ Sampling, Branched Path integrator, and displacement subdivision.


What is the fastest way to snap a bone to an object origin?

There are a couple of things you can do to speed things up.
First option is, assign hotkeys to snap to cursor/snap to selection.
Second option isn't actually in edit mode at all, but in pose mode.  Turn off locked object modes (in main edit menu), then select object, shift select bone, ctrl-shift-c (add constraint)-> copy location.  Don't worry about applying until you're done with all bones; when you are, select all, ctrl-a -> apply selected as rest pose, then use a "clear pose constraints" operation.
Hotkeys may vary depending on initial startup options chosen.
Neither of these is faster if you're doing a single bone.  But once you're doing it for five or more bones, they get a lot faster.


How to render object in front of everything else?

Create two scenes, one with the tree only and the other with the robot only.

The robot scene should have a transparent background (Select Film Transparent in the Rendering Properties menu).

In the Compositor mix the two scenes using the alpha of the robot scene as mix factor.


The file type is .blend, but it is not a format you can just save to like an image file format. You will need to look for an exporter to go to maybe .obj file format or something like it that handles mesh and materials together.


Cycles. How to prevent shadows when using backface culling

To remove the entire shadow as well as the backface culling you could simply combine the Backfacing socket of the Geometry node and the Is Shadow Ray socket of the Light Path node and use that as the input of your Mix Shader as follows :

However, removal of the shadows of just those culled 'backfaces' is compilcated by the fact that the 'Backfacing' socket is dependent on the actual ray being considered. This means that using the Backfacing output to cull the backfaces for the Shadow rays will result in different faces being culled for the shadow than are culled for the camera view - this is presumably not the desired behavior. This would be less apparent when the light sources are close to or behind the camera and would become more significant as the light sources move away from the line of sight of the camera or viewport - and the shadow would not match the mesh.

To resolve this must use a fixed point of view for the backface culling for the Camera rays and the Shadow rays and, ideally, all rays. This will ensure that the view of the material will match its shadow. As the hidden faces are based on the camera view it will be possible to see the back of the faces via reflections.

To acheive this, use the following node setup :

The Combine XYZ node defines the Vector of the Point of View. For 'traditional' backface culling this would point directly between the object and the camera and this would then result in all 'true' backfaces being culled. The node tree is split into a number of frames for clarity. These are as follows :

Shader - Transparent and Diffuse shaders mixed via the Mix shader based on the combined output of the other frames.

Frontfacing - Uses the Dot Product to determine the direction of the surface Normal in relation to the Point of View vector. A positive result will indicate that the Vector is in the same direction as the Normal - ie, it has been struck on its 'Front' face. The Subtract and Multiply nodes are used to filter out the actual 'Backfacing' rays since those need to be handled differently due to the 'Normal' of the face will having been negated.

Backfacing - Similar to Frontfacing but to deal with Normals that have been negated due to the incoming ray being incident on the 'backface'.

The results of the Frontfacing and Backfacing frames are combined via an Add node and then passed into the Mix factor.

The input Vector can be manipulated in Worldspace coordinates to point in the direction of the camera. However, a more versatile approach is toautomatically generate the vector based on the position of the camera or other target object. As the camera or objects moves, drivers can be used to get the associated coordinates and these can be used to generate the required vector for the culling as follows :

Here is an example of the back face culling with shadow emitted only from the 'visible' non-culled parts of the mesh :

And a demonstration of moving the culling viewpoint (shown as a glowing disc) :

Blend file available here


As @james-t and @Christopher-Bannett wrote in the comments, edit mode needs to be exited first and then re-entered under the new object.
Thanks guys!!