How do I link multiple meshes to one armature and apply Inverse Kinematics without distorting mesh?

Alright, so what you want to do is first make a bone rig that follows the mesh. You then want to parent each bone to the mesh, using empty weights. If you move the armatures now, nothing happens. There are empty weight paints that are parented to each armature.
Now, you want to select the armature, go into the Object Data properties tab, go into viewport display, and select names. This will show the name of each of your bones. Then, select the horse bone, and figure out which armature bone should move it. Since you have "Show names" enabled, you  should be able to see the name of the armature. THen, with the horse bone selected, go into edit mode, and press "A" to grab all vertices. Go into the object data properties with your horse bone selected, and under vertex groups you should see the name of the armature one that you what it to be parented to. Select the vertex group, (while in the horse bone's edit mode) and click assign. now if you move the armature, it should move that horse bone.


When building a physics simulation it's important to ensure it fits with 'real world' proportions and properties in order to achieve a realistic simulation.

Firstly, ensure your surface Normals are pointing in the right direction. You can view your normals in Edit mode (Tab), opening the Properties side-bar (N), scroll down to Mesh Display and enable 'Display face normals as lines'. This will display short blue lines at the centre of each face to indicate the face 'direction'. For physics collisions to correctly detect 'inside' and 'outside' you should ensure your normals are all pointing 'out'. If you need to adjust the normals there is an option to 'Flip Normals' (change the selected faces to point the other direction).

Ensure your objects are all at a 'realistic' scale in the real world - if you haven't set a specific scale on your scene (eg, Metres, Millimetres, etc.) then you can assume 1 Blender Unit (the units that your dimensions of objects are measured in) will represent 1 metre. Note that the scale is important for the physics simulation - the forces resultant from a falling 0.01m x 0.01m x 0.1m block (eg, similar size to a Jenga block) will be considerably different to a 1m x 1m x 10m wooden beam - even though the proportions are similar.

If your objects have had their 'scale' adjusted (using the Scale tool) you should ensure you 'Apply Scale' to have their new scale affect the simulation. This can be acheived by selecting the mesh in Object mode, pressing Ctrl+A and select Scale.

Finally, set the object's Mass to a realistic value for the behaviour of that object you desire. This is available in the Physics panel of the toolbar panel on the left-hand side (T) by clicking Calculate Mass. This allows you to select the material of that mesh to use in the physics simulation, such as Cork, Iron, Brass, Concrete, etc. - or set a Custom density if none of the preset ones are suitable.

Note that it can be beneficial to increase the Steps Per Second and Solver Iterations settings above their defaults (60 steps per second and 10 iterations) but care must be taken when increasing them too high as higher values result in shorter "timeslices" each time Blender evaluates a "step" in the simulation. Shorter timeslices result in much smaller forces and motions and the precision can result in rounding errors, adversely affecting the accuracy and realism of the simulation.


Blender Misaligned address in CuCtxSynchronisze

I figured that i can use OptiX rather than normal CUDA rendering on my GPU. So i used optix and it worked well! No pauses and even faster rendering.


How to apply a complex mesh object (in a plane) over rounded/curved surface without distorting beyond recognition

Here I show how you can try using a curve deform:

you see three objects selected:

a curve, converted from a tank profile strip of edges
the original logo mesh (aside)
the logo mesh deformed by the curve


Physics simulations take way too long to bake

Separate your rendered world from your physical world.

With soft body physics, your vertex count is the biggest thing that's going to impact the time it takes to calculate.  Physics complexity is combinatorial in nature.  Each bit capable of interacting has to check with every other bit capable of interacting.  So doubling your vert count slows down your scene by much more than half.

How do you get around this?  By using simplified proxy physics objects.  You may need a thousand verts to render your beautiful sphere with nice glossy reflections, but do you need a thousand verts to simulate its physics?  No.

Look at your first image.  In that image, you have wireframes of four objects, each of which has more than a hundred vertices.  Yet the actual profile of these objects is pretty flat.  Do you need all those vertices for physics, or do you only need those vertices for rendering?  If you don't need them for physics, make an octagon mesh collider instead.  Simply disable rendering on your new octagon collider, and possibly parent your rendered object to the octagon, rather than involving these thousand vertices in your simulation.

What if you have something soft and squishy, and the render needs to represent that?  One way to handle this is to use a physics object as the target of a mesh deform for your rendered object.  Another is to use an armature with constraints that track vertex groups on your physics object.  These kinds of deformations can be computed much more quickly than physical deformations can.  Use your physics as a guide for your render.  Don't try to render physics directly.


Weird Mesh/UV problem cant seem to fix it

Just a quick look and I figure it out.

Every mesh has two materials applied.

Deleting one of them will solve the problem.

The bad news is: You must repeat it with every mesh.


Why is soft body modifier always on top of modifier stack?

If you can read the error message at the top it says, "Can't move beyond a non-deforming modifier". It basically means deformation modifiers are always on the top.


Why is the Track to constraint "legacy"?

After some further research, I found that Joshua Leung added this text to source/blender/makesrna/intern/rna_constraint.c when he committed the new Damped track constraint, indicating that Track to has been superseded by Locked track and Damped track.

Of course I don't think anyone's about to deprecate Track to.


Object moves back into origin everytime i open the blender file

there is a keyframe set on your object. That's why it moves back to original location and scales down.

You will need to open the N-Panel (see below) by hitting N and then right-click on any illumined fields and choose "Clear Keyframes"

As for not being able to apply the location, your object is a multi-user (it shares data with other objects). You will need to make it a single user by clicking the number icon here:

I hope this helps!

-Adam

EDIT: Also, if there is appears to be no keyframes set and the object still jumps back to another location, it may be controlled by an NLA strip. Open the Non Linear Animation window and delete the action that is affecting it.


How to control specular/glossyness of glass shader in cycles

If I understand you correctly, you can simply mix a Glass Shader with a Refraction Shader.  The factor will determine how reflective the glass material is:


How to animate dynamic scaling and z offset in Array modifier

Using an empty as Object offset to control the array modifier will give you a lot of options.
If you play with the reltive offset you can get things like this:

Changing the distance and size of the empty you'll control the relative distance of the cloned items in the array.

You can then add keyframes:

By adding a lattice on the scene and a lattice modifier to the plane to the stack you can further control the deformation (as in the opening of the video used as reference on the question:


This kind of issues arise when you try to smooth the weights of the main area bone (in your case the neck bone) but you forget to smooth the neighbour bones (probably the head bone).

In particular if two adiacent vertices have the same minimum weight (let's say 0.001) to the head bone, but one belongs to the head bone only while the other has a tiny amount of weight from the neck bone also, their deformation will be completely different, no matter if they look the same pale blue in weight paint mode: if a vertex belong to a single bone/vertex group only, it will follow the movements of that bone exactly, even if its weight is very tiny.

I'm pretty sure that if you highlight the head weights, you will see that they end exactly where you have the sharp corner, and this is where you'll have to use the smooth brush until you reach the desired deformations.


Hotkey to set playhead to Left mouse click

Shift + Right Mouse Button
At the top of the hotkey list is a search box, search for change frame and see/set the Sequencer value.


Your mesh topology is not good. You have inside faces (look into your mesh) – delete these.


Jagged/Black edge artifacts when modeling

Reduce your Clipping Distance for both the viewport and/or camera.

You have it set to $0.1$ - $10`000$ while you work at around a scale of $1$.

If you reduce the Clipping Distance to something reasonable like $100$, the artifacts disappear.

Clipping distances are used to calculate the Z depth buffer, which is the scene depth information, since it is limited to the available grey scale values of an image stretch across the whole depth of what is displayed, if the values are too far apart there is not enough precision left to represent minute details.

Always keep these values as close as possible to comfortably work, and with a magnitude matching your scene unit scales.


How to show subdivisions on one viewport only?

You can 'kind of' get close by disabling overlays in one viewport
Then you have one viewport with vertices, and second one showing only the final result.


How do I use blender masks to make it look like there is magic in my videos

Be more specific, because as a fellow avid magical enthusiast, there are a plethora of ways you can make magical items. Adding emission to make it glow, adding volumetric shading (volume) around the mask to make it look spooky, a change in texture, and/or even distorting the mask is an effective way to make it look like it reacts to hand movements.


increasing amount of side faces on object made from cylinder

Mesh Objects in Blender don't have an Edit History that would allow you to edit a parameter somewhere at the start of the Object's life and have that propagate through all other operations to the present. You can't in your example change the tube's vertex count after you've made edits to it.

But it is possible to reconstruct the object quickly with the desired vertex counts. For instance use the Screw Modifier to Lathe the profile around an axis. The Object's center can be used as the rotation coordinate or an Empty.


In the 3D viewports menu bar, enable snapping by click the Magnet Icon. Next to the icon, in the snapping to dropdown menu. Select Face, since you want to snap to a face and choose Active.

By moving an object in object mode you can snap its origin to other faces. Go into edit mode ↹ Tab, go into face mode 3. Select the face which you want to snap (it gets highlighted as the active face) and add all other faces which you want to move to the selection. (Box Select or A)

Press G to move the geometry and by hovering over the face of the other object with mouse, the face snaps to it. Press X during the G operation to constrain the movement to the X-Axis.

If you want to automatically modify the orientation while snapping to an oblique face, check Align Rotation to Target in the snapping settings.

The position the objects center at the face you wish to snap and snap it in object mode.


Black and white gradient on surface, where is my red color

I'm not sure a factor output should even be able to show red the way he has it set up in that video, or it is possible that this behavior has changed since January.  In one of the next steps he disconnects this factor output and makes a new color output into a Principled shader, so I would just skip ahead to that part, I think.


Nevermind!
This is typical, search for an answer, found nothing.
Post in stackexchange, found the answer immediately..

Here is it described what i was looking for!


BGE Problem with Automated Door (Can't Pass Through)

The physics mesh for an object is created at game start, and is not updated based on animations. For some reason armatures, even if they move the whole object, don't seem to update the physics mesh

In this case, it would be easiest to make the elements of the door non-collision, and animate a separate object (eg a cube) that slides up and down to let the player in - without an armature.


1.pic: Make a cylinder like this (hit Ctrl+R to make edge loops)

2.pic: Turn on proportional editing (sphere), select the marked verts and move them apart with scaling "s key" use the mouse scroll to adjust ray of the proportional editing.

3.pic: Switch to smooth the proportional editing, select the marked faces and rotate them around the z axis R key and then Z key.

4.pic: Go to object mode and add a solidify modifier

5.pic: Click on smooth shading, turn on auto smooth and adjust it

6.pic: If you go to edit mode, select all faces by A key then hit Ctrl+T to triangulate the faces the surface will be smoother, but the topology will be worse.


Instead of using a movie clip node use an Image Sequence node (you can also load videos in it)

Then you will have control of how many frames to use, at what point in time and offset.

To hold the last frame just untick the Cycle box

See these related links:

https://blender.stackexchange.com/a/9123/1853

https://blender.stackexchange.com/a/8985/1853


It seems like you have only opened the image in image editor but you haven't given your material the image texture.

You can give your material image texture by clicking the yellow dot next to Base color and by choosing Image Texture.

Next press Open and find your image.


Having troubles adding material to a subdivided face

Unwrap doesn't affect the material. Apply the modifier then go to edit mode, select the faces what you want to assign with the second material and select the second material, then click on assign.


How to texture paint one image over another image, while still keeping the background color of the first image

One way to do this is to prepare your sheet music image with a transparent background. Select the black notes and text and invert the selection and remove the white background. Export this as .png.
In Blender, UV Editing mode create a new image and unwrap your object. After unwrapping and before texture painting, create two new textures in Texture Properties tab, one with your base of old paper and another texture with your notes on a transparent background.
In Texture Paint mode, paint the base coat, then switch the texture to your notes and text, and paint over the base coat. Save the Image, and then apply it as an image texture into the Base Color of the Principled BSDF.
Hope that helps, I think mixing the images in this case will want to produce a slightly washed out mix of the old paper with the bright white of the sheet music. But give that a try and see if you like that result better.


blender python: evaluate extruded curve points

You can use object.to_mesh():
>>> curve_ob = bpy.context.scene.objects['MyCurve']
>>> me = curve_ob.to_mesh()
>>> me.vertices[0].co
Vector((0.0, -1.0, -0.6200000047683716))

This allocates a mesh object specifically for the prupose of being manipulated using Python. You can then free this extra memory with object.to_mesh_clear().


Hi here is some quick code from the python console,

I have an active object with a number of shapekeys, "Key 1" being one, I find the index using find(...) then set the active_shape_key_index to this number.

find(...) will return -1 if a key of that name is not found.

>>> index = C.object.data.shape_keys.key_blocks.find('Key 1')
>>> index
1

>>> C.object.active_shape_key_index = index
>>>


A current "lazy" approach to this. might be:

I use a few VD nodes here to emphasize the original Quad outlines (light blue), and the resulting interpolated outer edge (red). Note that the Plane (Mesh) Object has a Vertex order which is [0, 1, 3, 2], and we need both Verts and Edges to order the vertices (using Vector Sort) for the "connected" algorithm to get [0, 1, 2, 3].

The Smooth Lines node offers "Weights" input. When using the slider all verts are treated the same, but you can pass it a list of values (ranging from 0 to 1) to effect vertices uniquely.

I feel perhaps that this does not provide a full solution to your question, but sometimes even a partial answer can be useful.


Is there a way to render out an animation from the 3D view?

Click the movie icon beneath the 3D View

Here is the menu venue


No, that is a red spot in the image you are using as environment (it seems a red "camera" led)... :) it is just reflected by your glossy phone model.


Right now, I am using Blender 2.90. Here is my Python code to detect and use GPU in Blender.
import bpy
bpy.data.scenes[0].render.engine = "CYCLES"

# Set the device_type
bpy.context.preferences.addons[
    "cycles"
].preferences.compute_device_type = "CUDA" # or "OPENCL"

# Set the device and feature set
bpy.context.scene.cycles.device = "GPU"

# get_devices() to let Blender detects GPU device
bpy.context.preferences.addons["cycles"].preferences.get_devices()
print(bpy.context.preferences.addons["cycles"].preferences.compute_device_type)
for d in bpy.context.preferences.addons["cycles"].preferences.devices:
    d["use"] = 1 # Using all devices, include GPU and CPU
    print(d["name"], d["use"])
```


Will this mesh work to rig and animate the lips?

Depends on what you mean by "rig."  If you provide proper weights and proper bones, yes, it will deform, basically how you tell it to.

If you're referring to autoweights, then it might be useful to think of weights as a fluid that can "spill" out of holes in the mesh.  Holes like this can cause undesirable weights from automatic weights.  But it's easy to fix: just face the hole (ngon is fine) before you autoweight, then delete the face afterwards.

Note that your eyes are just as much a source of this issue as your mouth.

Finally, you might mean, will this deform well?  To answer that, I'd really need to see a wireframe, but from what I can see, no it will not.  It appears that your face is a big grid without any attention paid to edge flow.  You should start looking for references on face topology.


Blender collision export primitives issue

I found that blender .bullet export (for primitives) does not export correctly if:
1. “Apply Object Transform” for Location or Rotation is performed. This is not reversible quickly
2. The “origin” is not at the object bounds center (i.e. 1a was performed, location reset to 0)
3. Rotation in blender != value you want (i.e. 1a was performed, rotation reset to 0)
4. Scale in blender != 1.0 (i.e. 1a for Scale was NOT performed)
5. Something moved in the scene before the script ran


Script for simple finance calculations in blender?

Ben Simonds has an addon (based off work by Bassam Kurdali) that can animate text in a variety of ways. The script is available at github. There is also a short example video of what is possible.

Bassam's original script of a simple typewriter effect is somewhat simpler -

# ##### BEGIN GPL LICENSE BLOCK #####
#
#  This program is free software; you can redistribute it and/or
#  modify it under the terms of the GNU General Public License
#  as published by the Free Software Foundation; either version 2
#  of the License, or (at your option) any later version.
#
#  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.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software Foundation,
#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ##### END GPL LICENSE BLOCK #####

# <pep8-80 compliant>
import bpy
from bpy.app.handlers import persistent

bl_info = {
    'name': 'Typewriter Text',
    'author': 'Bassam Kurdali',
    'version': (0, 1),
    'blender': (2, 65, 0),
    'location': 'Properties Editor, Text Context',
    'description': 'Typewriter Text effect',
    'url': 'http://urchn.org',
    'category': 'Text'}

"""
Typewriter Text Animation For Font Objects
"""

def uptext(text):
    '''
    slice the source text up to the character_count
    '''
    source = text.source_text
    if source in bpy.data.texts:
        text.body = bpy.data.texts[source].as_string()[:text.character_count]
    else:
        text.body = source[:text.character_count]

@persistent
def typewriter_text_update_frame(scene):
    '''
    sadly we need this for frame change updating
    '''
    for text in scene.objects:
        if text.type == 'FONT' and text.data.use_animated_text:
            uptext(text.data)

def update_func(self, context):
    '''
    updates when changing the value
    '''
    uptext(self)

class TEXT_PT_Typewriter(bpy.types.Panel):
    '''
    Typewriter Effect Panel
    '''
    bl_label = "Typewriter Effect"
    bl_idname = "TEXT_PT_Typewriter"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = 'data'

    @classmethod
    def poll(cls, context):
        return context.active_object and context.active_object.type == 'FONT'

    def draw_header(self, context):
        text = context.active_object.data
        layout = self.layout
        layout.prop(text, 'use_animated_text', text="")

    def draw(self, context):
        st = context.space_data
        text = context.active_object.data
        layout = self.layout
        layout.prop(text,'character_count')
        layout.prop(text,'source_text')

def register():
    '''
    addon registration function
    '''
    # create properties
    bpy.types.TextCurve.character_count = bpy.props.IntProperty(
      name="character_count",update=update_func, min=0, options={'ANIMATABLE'})
    bpy.types.TextCurve.backup_text = bpy.props.StringProperty(
      name="backup_text")
    bpy.types.TextCurve.use_animated_text = bpy.props.BoolProperty(
      name="use_animated_text", default=False)
    bpy.types.TextCurve.source_text = bpy.props.StringProperty(
      name="source_text")
    # register the module:
    bpy.utils.register_module(__name__)
    # add the frame change handler
    bpy.app.handlers.frame_change_post.append(typewriter_text_update_frame)

def unregister():
    '''
    addon unregistration function
    '''
    # remove the frame change handler
    bpy.app.handlers.frame_change_post.remove(typewriter_text_update_frame)
    # remove the properties
    # XXX but how???
    # remove the panel
    bpy.utils.unregister_module(__name__)

if __name__ == "__main__":
    register()


Output from the node editor to the sequence editor

In the VSE preview window press the N key to show the Properties Panel. Look for Scene Preview Render. Turn off Open GL Preview.

This should allow the compositor output to pass to the VSE.

If you had pressed the render button (F12), you would have seen the correct view.

EDIT:
Change the scene strip property > blend type to Alpha Over or Over Drop.


Simple code to modify material of an object

You can:

import bpy

#Get the object
obj = bpy.data.objects['Cube']
#Get the material
mat = bpy.data.materials['Material']

#Check all is ok
if obj and mat:

    #If a material is already assigned (material slots is not empty)
    if obj.material_slots:
        #Assign the material to the first slot
        obj.material_slots[0].material = mat
    #If no material is assigned
    else:
        #Create a new material (link/slot) for the object
        obj.data.materials.append(mat)

Explanations:

Materials are stored at two levels: object and data

'data' contains an array of materials (obj.data.materials) that allows to link the material to the object's data.

'obj' contains an array of material slots (obj.material_slots) that contains slots which give a link to the material itself (obj.material_slots[0].material) and other properties (name and link). This material is not necessarily the same as the corresponding obj.data.material (see 'link property' below).

These two lists are internally maintained coherently.

The 'link' property of the material's slot can be either 'OBJECT' or 'DATA'.
That corresponds to this is the UI:

This distinction is useful when you 'duplicate linked' AltD an object. In this case:

If the link is 'OBJECT': each duplicate can have its own material in the material slot
If the link is 'DATA': all duplicates will share the same material

So, if we come back to the code:

#If a material is already assigned (material slots is not empty)
if obj.material_slots:
    #Assign the material to the first slot
    obj.material_slots[0].material = mat

In the first case above, using a previously created slot will assign the material coherently to the link property.

#If no material is assigned
else:
    #Create a new material (link/slot) for the object
    obj.data.materials.append(mat)

In this second case, we assign a new material which will correspond to a new slot and a default 'DATA' link mode.


Cutting out a part of a plane from sphere vertices

Here are some steps for you. (Since you'll will surely make your catapult like a solid object)

First create a Uvsphere with default options.

Now, in edit mode, Select the Top half Vertices of the Sphere.

Delete Them.

press Ctrl+A to select all the vertices , Then Press E to Extrude and immediately press ALT+S to Scale the Uvsphere. Scale it outward to get a shape like this.

Now, press Ctrl+Tab and Select "FACE" selection mode. Select the 2 faces on X axis.

Now, Simply press E to extrude and the G to move & X to constrain the movement on X axis. Move it out ward. then Press S & X & 0 to even out the extrusion.

And , Here is a link to file
Blend File


How to precisely rotate object to align with 3D cursor via Python script?

You can use the Vector.angle function to find the angle between an arbitrary axis vector (like the Z axis "up" vector), and the 3D cursor. This will provide you the angle you need to rotate your object to align it with the cursor in that specific axis.

import bpy
from mathutils import Vector

curloc  = bpy.context.scene.cursor_location # Cursor location
up      = Vector((0,0,1)) # Positive Z axis
right   = Vector((1,0,0)) # Positive X axis
forward = Vector((0,1,0)) # Positive Y axis

o = bpy.context.object    # Active object

# Calculate angle between up and cursor vectors and set as Y rotation
o.rotation_euler.y = up.angle( curloc )

Notice that in the example above I'm aligning the object with the cursor on the Y axis specifically. You can change this by replacing the axis letter on o.rotation_euler, to align with a different axis.


Cycles baking will not produce same colors

Your Normals are flipped. In Edit Mode, select everything and go to Mesh > Normals > Flip Normals.


Hi Zim in this case its best to use the ShrinkWrap or KnifeProject. The 1st one is more simple to use so thats what we try. I prepared the scene looking like this:

You could see the road above the terrain so now its good to make the road subdivided (preferably more that the terrain) for ShrinkWrap being possible so use Subdivide to achieve this result:

Its enough to acomplish what we want so now the modifier takes place. Add it and as a target choose the terrain object (in my case its "Plane"). Now use the settings as below (GREEN). As a MODE use the Project and dont forgot to check the Negative projection (in our case we have road above the surface so its negative). Also dont forget to set the Offset to about 0.01 (lets try lowest value possible) to avoid overlapping faces.

Everything is done so hope it helps Buddy.

Sincerely, Jan


Problem with Boolean modifier-difference

The reason boolean difference fails on the 4 is due to non-manifold geometry. You can select non-manifold geometry with CtrlShiftAltM in edit mode. In your case, this reveals an unconnected face on the extruded version of the 4 (likely due to an extra edge before extruding):

I added an extra edge ring and merged the corresponding faces:

And then the boolean succeeds.


Problem

You cannot scale it because of the Zero-product Property. This is a mathematical theorem that Hotmath defines by saying:

  The Zero Product Property simply states that if a*b=0, then either a=0 or  b=0 (or both). A product of factors is zero if and only if one or more of the factors is zero.

This relates to your issue because you are trying to multiply the dimensions (let the Object Dimensions be represented by a) -- set at 0 -- by a non-zero value (let that random, non-zero value be b). As Blender follows the various laws of mathematics, the dimensions will always return to zero.

Solution

When first you add a Plane object and before you click on anything else, you should be presented with a number of settings in the Toolshelf on the left side of the 3D Viewport. Make sure the Radius: value is set to a non-zero value. If it is set to zero, it will likely spawn at zero each time you try.

Bad:

Good:


How to create perpendicular edges along one direction?

You can achieve that by creating a plane and subdividing it using Ctrl + R into parallel equally spaced edges, then using Knife Project tool, you can project your object to the plane, all you need to do later is to remove all the faces that fall outside the projected faces.
But looking at your file, you need first to turn your object into a mesh using Alt+C and choose Mesh from curve, then in edit mode, select all, press X and choose Limited Disolve, in order to reduce the vertices in your object.
Here's your edited file:


Unexpected "color" transition in half transparent cylinder with Cycles

It seems that the reason of this shading 'glitch' is topology of your Cylinder. I don't know exactly why this is happening, maybe because of stretched faces (or for sure). When you scale it down on the X axis (to make it shorter) problem disappears.

You have two options:

Add Subdivision Surface modifier.

Add Loop Cut in the middle of the Cylinder (or couple of them to be sure that it doesn't happen again.

Personally I would go with second one as this is 'lighter' solution.


Window menu "Make Screencast", the settings are in the User Properties view. If you want to do anything serious use a third party piece of software. In windows the Game recorder works well. – rob Oct 10 at 8:49


How can I apply these textures to my model?

First of all you should change the Color Space of the Height texture to "Non-Color" since you only have to use it to give height information for the material; basically black means "no height here", while white means "yes we have height here" and all the grey values in between mean "we have some degree of height here".
I don't think you need the mask map since it's not used on models but for mixing other materials usually.
The mix shader is useless in this case because you only have one shader (Diffuse).
Be sure to play with the Strentgh value of your bump node, 1 is usually too much so I'm pretty sure you wanna lower it.
If you have some other texture like specular and roughness you should substitute the diffuse node with a Principled BSDF so that you can connect them in the proper channel, they have to be set to "Non-Color" too by the way since,  like the height map, they don't give color information.
In the end you should have something like the image below, notice the Specular and Roughness channel on the Principled node.

I hope my answer helps you, if you have have questions feel free to ask.


Video format/encoder settings that don't destroy image?

The short answer is that you can't.

The longer answer is that it is an extremely complex series of transformations to take something from the RGB domain to the YCbCr domain, as outlined here.

Finally, even if you manage to leverage a 444 output stored in YCbCr that doesn't decimate your work, the output from Cycles is known as scene referred data. This data cannot be captured properly in a PNG nor any codec format. For a larger explanation into some of the nuances of this, see this question and answer.


Make particles face outwards of object center?

Unfortunately you are not able to do that simply with particle system, but there is a workround:

Go to Modifier stack, clock Convert button on Particle System panel to convert these particle trees to real duplicates. Then disable the renderability and visibility button, or delete the particle system. (You may want to then deselect the earth, then group all selected trees for easy control in the following steps)
Select one of the trees, add a Track To constraint, set the "earth" as target (or use an empty object that shares the same origin location).
Use Copy Constraints To Selected Objects operation to copy the constraints to all trees. (You can find it in Objects > Constraints menu, or simply search it by hitting specebar).


A Hollow Hole Around The Equator Of A UVSphere

-Select that inner ring.
-Ctrl-B and drag to desired width.
-E (extrude), S (scale), Ctrl-Shit-Z (so it does not scale to Z axis)
-Done
I hope thats what you needed!


how to correct topology after boolean operation?

First triangulate the model.
After that, add a subdivison modifier, with simple and one with Catmull-Clark selected. Then do loopcuts, where you want to have sharp edges. Slide the loopcuts till the edges, but not on them, just a little bit before.
You have to play a little bit with the strengt of the modfiere.


How to merge a loose edge into coplanar faces?

AFAIK, there is no way to use an edge (without even a plane) to divide a face.

What you need to do is delete the edge (x->edge) and then join the two verts, by selecting them and hitting 'j'.

If you've made a bunch of edges not realizing what you were doing in some other model, you can use mesh->cleanup->delete loose to delete all these edges, but I don't believe there's any way to transform them into cuts.


To expand the render distance in your viewport, increase the End field in the view properties panel.

Show the properties panel by pressing N, then go into the view tab to change the setting.


How to repair procedural texture for animation?

if you uncheck this (bind to vertex groups), it works. Although i am not sure whether you need this... ;)


Extrude Region (Vertex Normals) stopped working properly

Extrude region with vertex normals behaves nearly like extrude region if the pivot point is set to individual origins.

Set the pivot point back to median point to have the expected behavior :


When I touch an object that I'm meant to pass through I spin randomly out of control

First, make sure that "Ghost" is checked and "obstacle" and "collision bounds" are unchecked in physics. Check that the base and top face are far enough up apart on the Z axis so they do not collide with the avatar. You may want to change the cube into a plane to prevent this from becoming a problem.
It would help to know what version of blender, it may be a bug, and what your logic bricks look like.


How can I use vector mapping to control the Anisotropic shader?

Tangent (Radial) vector is different from Texture coordinates (cartesian)

The Anistropic shader is not using the Generated Texture coordinates input as default because, as you correctly noticed, there isn't a Vector socket.

The two vector-type input present in the shader are:

Normal (it's used for providing a normal map to the surface)
Tangent (this one controls the anisotropy direction of the material)

If the last mentioned socket is left empty, the default Tangent vector is being used, that corrisponds to the Tangent node in Radial mode and Z axis.

But what exactly how the Tangent socket affect the shader result?

As we know anisotropy means that the material has different properties in different directions; the Anisotropy shader is like a Glossy shader but with reflections that are "stretched" upon a certain direction. The Tangent input drives the direction on which the light is stretched:

Using the UVmap mode can help you in controlling the direction of the tangent ( the V direction in the UV space).

The reason you can't easily tweak the tangent with the vector mapping is because the values don't have nothing in common with the position of the shaded point. Here's what the Tangent (Radial Z) component X looks like:

The operations that the Mapping node is capable of (multiply, add, rotate..) would not result in a shift of the Tangent vector in the 3D space. While the Texture coordinates are in a cartesian coordinate system, so if you add 0.1 to X, the texture shift along the X axis, adding 0.1 to the radial-mapped values of tangent node instead, will result in a change of the circular sector, but the center will always remain still (it even has an undefined value).

A possible workaround for this situation could be to emulate the vector result of the tangent node with a Texture coordinates node that you'll able to tweak with the Mapping node, or maybe using an empty as origin. The trick consist in moving the center and, only after that, reconstruct the "radiality".

Starting from the Object's coordinate, just get rid of the Z component and Normalize the vector.

Now you can move the empty, or add the mapping node just after the Texture coordinate node as usual, in order to set the convergence point of the anisotropy property.


How to store the contents of a variable in a file?

I don't use BGE so I don't know how it works in BGE, but if you needed to store a value in a Python script in Blender you could store it as a custom property. The property can belong to pretty much anything, for example the current scene:

import bpy
bpy.context.scene['some_number'] = 50

When this script is run, the property gets saved with the current scene in the open .blend file. It can then be accessed by another script:

import bpy
bpy.context.scene['some_number'] += 15
print(str(bpy.context.scene['some_number']))

Everytime the script runs it adds 15 to it so the output when the script is run 5 times will be:

65
80
95
110
125

Obviously, if you open a new scene bpy.context.scene will point to a different scene so you could use a property of bpy.context.window_manager if needed.

You can use a file as well, you do not need bpy for that:

file = open("C:/SomeFile.txt", "w")
file.write("Hello World")
file.close()

file = open("C:/SomeFile.txt", "r")
text = file.read()
print(text)
file.close()

It is important to make sure Blender has write permissions in the directory used for creating the file. C:/ might be protected by the OS. You can just use your project's directory.

I don't think it is possible to write to Blender's text block this way. I might be wrong here. It does not seem to me like a very elegant way to store a variable anyway. I would use custom properties.


Here are the steps:

Select Cycles for Render Engine
Select Experimental for Feature Set
Select Dicing Rate and Preview count in Subdivision drop down
Select Subdivision Modifier from Modifiers tab but do not apply it
Check Adaptive check box and choose dicing scale
Done!

I hope that helps


You may first wish to make sure these vertex groups aren't being used for something else such as particles, shape keys, modifiers, etc. Vertex groups are used for a lot of different things besides just bone weights. But assuming you still want to remove these groups, it can be done like this:

Make sure all the bones of the armature are visible. With the armature selected, go to the Object Data Properties tab of the properties panel, and make sure all the Layers with bones in them are visible (the ones with a dot have bones). Shift + click to select multiple layers.

Enter weight paint mode. From object mode, first select the armature, then select the mesh by Shift + clicking on it. Press Ctrl + Tab and select Weight Paint

Select all the bones by pressing Ctrl + A

Lock the selected groups from the menu at the top of the viewport. Weights > Locks > Lock Only Selected

Or if you want to preserve some other vertex groups as well, use Lock Selected instead, and make sure all the groups you want to keep are locked.

Delete the unselected groups. In the mesh's Object Data Properties, press the drop-down arrow on the right of the Vertex Groups section. Then select Delete All Unlocked Groups.


Tank track deformation rigging for Unity. Worked well before, fixed a problem and created more

First you can delete the faces on the sides of the track segments, where they connect. These will end up on the inside of the track where you can't see them, so you don't need them.

When you merge your track segments (to get rid of the staircase effect) by checking the Merge box in the Array modifier, you can also check the box First Last to close the loop. It doesn't always work though, like in my example.

But that's not a problem. : )

You can close the loop manually in Edit Mode, after applying the modifiers. Select pairs of vertices than need to be connected and press F. Then use F to make faces between the newly created edges.

Or select al the 8 vertices you want to connect and do Edge > Bridge Edge Loops.

Or you can add a Weld modifier, and increase the distance until the gap is bridged.


Rigging character; Keep Offset not working?

You have to jump into 'Pose Mode' right after parenting.  Then try rotating the bone.  From the looks of it, you have everything else right.


How do I copy a pose from one blend file and paste it to another?

With your armature selected look in the properties panel at the object data tab.

The first thing you see at the top of the tab is your Pose Library pannel

Create a library and add your pose to it.
http://wiki.blender.org/index.php/Doc:2.6/Manual/Rigging/Posing/Pose_Library

save your blend.

in your new blend, you can append the pose library (from the Actions folder).
You can then add the poses via the Action Editor


Bridge edge loops not bridging to nearest vertex on adjacent edge loop?

An easy way to create face between the loops is to not treat the as edge loops.

⇧ Shift RMB select two opposing edges and delete the X > Edges.
Select the opposite "end" vertices each and connect them with an edge F. You now have a single loop.
Selec this loop ⎇ Alt RMB and fill it F with an n-gon.
Triangulate the ngon with ⎈ CtrlT.
Select the four vertices which we disconnected at step 1 and fill the face F.


Is there any documentation or tutorial on how to replicate the Blenrig 5 spine? or Rig an Armature controlled by its hips?

I've completed the spine.
I basically ripped the blenrig bare started with 1 set of bone groups and tried to link which bones were used and which weren't.
I now have a working spine controlled with the hips. image of it below.
Where i was going wrong was that the bones weren't parented to the correct bone and the torso master needs to be connected to another bone or you'll get the constraint glitch thing.


You can make the start frame negative. I would suggest changing the gravity settings on the particle to slow it down though, or use the particle's drag itself.


How can I parent a plane to only the y-position of my camera?

Using the Copy Location constraint on the plane, selecting camera as the target, checking the box for Y and Offset! Works perfectly!


Weird grainy texture in default brush in paint texture mode

I discovered that I had not applied the mirror modifier and that was causing the issue, apparently it was putting the model over itself and the brush did not know which one to paint.

After applying the mirror modifier and making sure I did not have double faces it worked fine.


Make closed curve not closed. Blender 2.8

All you need to do is click Atl+C again to open the closed curve.


Shader output as factor input for other shader nodes

Answer: Wasn't working as you can't plug BSDF into Color (rookie error).  I have fixed the problem (getting reflection and nice clear transmission by mixing a Transparency shader with Principled shader.  The Principled shader provides the reflection (which Transparency does not) and the Transparency shader gives a nice clear view through the glass without the thousands of passes needed for clear transmission.  Only missing the distortion that comes from refraction but an OK compromise for my purposes.


How do I mark a seam at an edge shared by 3 faces as a seam for only two of those faces?

The problem is that the roof has no thickness - so anything you do with one side of it (add creases, set material, etc) affects the other. You need to give the roof a thickness so that it has a proper 'inside' and 'outside' - this is referred to as being 'manifold'. There are various ways of achieving this but the simplest is to go into Edit mode (Tab), select all the faces making up the roof, and hit E to Extrude, and then move the newly generated faces up to form the solid roof (hit Z to constrain movement to the Z-axis then move the mouse up).


How to transform an 2D sketch into an 3D object with other texture in an animation?

There would be two parts to doing that:

Scale object on one axis to turn it from 2D to 3D

If you wanted to be rotating the object in the process, you may want to parent to an empty to animate the rotation, or you could use a lattice modifier to control the deform while it is moving.

Animate from a grey texture to a realistic texture.

You can animate properties in nodes the same as any other property in blender. Use a mix node and animate the mix value to switch from one material to another.


How can i create a realistic water material with foam in cycles for a water simulation

Use a float particle. Create an object like box > Go to physics tab select fluid, then apply fluid type as particles > check float (Note: there are 3 types  Drops, Float and Tracer) you'll probably need Drops and Floats, but will do float first and the rest I leave to you... The box that you added will be our emitter when you bake the domain make sure under the fluid particles that the value generate = 1.000 then tracer is equal to the number of particle count. Make sure before you bake that the cache location of the domain and the fluid particles are the same then bake... Then you'll see the emitter after baking. > Go to particles Tab you'll see Fluid Particles > select it and go to object place and add another object onto it make sure that the object's scale is a bit too small so it will appear realistic probably an icosphere with 1 iteration these method will definitely slow down your system if the object scale is quite too big. You can bring down the display to 10% just for viewing purpose not a 100% this method can be used for post bake... Result: Foam or particles will appear on your fluid when the fluis is disrupted or in motion then particles die if fluid is at rest... Hope this help... If you want to add another particles just use the same method just use a different count value in the fluid generate... (Note: Drops particles create splashes when fluid is at a peak, Tracer leaves trace like a raindrop on a glass it also leaves traces on the domain... P.S to make your fluid look good select domain > go to Fluid boundary > add subdivisions probably 2 smoothing 0 Or crank up final resolution to 200-400 for better fluid result..


Add modifier to selected and another to active object

I'd suggest not using modifier add operator and use modifiers.new(name, type) instead.  Avoids hassle of changing the active object and also if using the op to add a second modifier of the same type, would need to access it via obj.modifiers[-1] as it will be named "Solidify.001" or somesuch.

Result of Running Script on 2 default planes

import bpy
context = bpy.context

obj = context.active_object
# add a solidify modifier on active object
mod = obj.modifiers.new("Solidify", 'SOLIDIFY')
# set modifier properties
mod.thickness = 0.3
obj.location.z += 0.15
for o in context.selected_objects:
    if o == obj:
        continue
    # see if there is already a modifier named "SelectedSolidify" and use it
    mod = o.modifiers.get("SelectedSolidify")
    if mod is None:
        # otherwise add a modifier to selected object
        mod = o.modifiers.new("SelectedSolidify", 'SOLIDIFY')
    mod.thickness = 0.1
    o.location.z = 0.05
    # add a boolean mod
    boolmod = obj.modifiers.new("Bool", 'BOOLEAN')
    boolmod.object = o
    boolmod.solver = 'CARVE'
    boolmod.operation = 'DIFFERENCE'


If its an option to lose the abilty to edit the Text, one of the easyest ways to doo this would be converting the text to a mesh and use the boolean modifier on the grid with the text as the intersecting object.


To point a light to an object use a "Track to" constraint.

Set the target to the object you want.

Set

To= -Z

Up = Y

Now the light will always point to the target object.


I've done my best to recreate your issue, I think you've created several n-gons here, and the artifact you're seeing is Blender triangulating that n-gon.

You can create better topology in a somewhat automatic fashion by using a bevel on this corner.  I'll be starting over with a primitive cube, and I've just scaled up the bottom to create this tapered shape of yours.
Just select one edge and bevel it with the desired number of segments.

And then select the top corner's vertices and do a Merge At Center.

This has created a triangle for each segment of the corner.  Note that typically it is recommended to stick to 4-sided faces called quads, but the most important thing is to avoid n-gons unless you are looking for some very particular behavior.


Autosmooth causing subsurf problems with holes

In the mesh's Data tab, create a new vertex group. Select only the vertices along the hole profiles and a couple of adjacent vertex loops. CTRL+PLUS ("grow selection") on the numpad is good for this. Click the button that says Assign.
Now go to the smoothing modifier and choose this vertex group. This prevents smoothing on any unintended vertices.


Duplicating element with python, rigid body lost

The code you got from this answer does actually copy the rigid body settings, what it doesn't do is add the new object to the rigid body group. Without being part of the rigid body group the objects don't act as rigid body objects, even with the settings.

import bpy

scn = bpy.context.scene
src_obj = bpy.context.active_object
rbgroup = scn.rigidbody_world.group

for i in range (1,6):
    new_obj = src_obj.copy()
    new_obj.data = src_obj.data.copy()
    new_obj.animation_data_clear()
    scn.objects.link(new_obj)
    rbgroup.objects.link(new_obj)
    new_obj.location.z = i * 3


How to load and display an image in the image editor using python?

If the image editor is used in one of the visible areas of the current workspace, you can iterate through bpy.context.screen.areas to find the one with type IMAGE_EDITOR. The image that is shown in the editor can be set through the space of the area.

An image can be loaded through bpy.data.images.load().

import bpy

img = bpy.data.images["Render Result"]
# img = bpy.data.images.load(filepath)

for area in bpy.context.screen.areas:
    if area.type == 'IMAGE_EDITOR':
        area.spaces.active.image = img


How do I turn off confirmation dialogues?

I don't know if you can user configure it, but you can speed up the editing by pressing XD.

XEnter or X1 also works, but it's probably slower. You also can change the default shortcut for delete to D and then press D twice.


[FR-EN] Advanced Moving Script for the BGE V2.0 by Hack0re.

Warning, this script only work with Character Physics Type.

It does not work with Dynamic Physics Type.

The script include 95% of the instructions, in French and in English (142 Lines Header).

I will add more improvements in the near future...

Its my first real script, i just started in python, please be indulgent.

Features:

-Perfect for a FPS game.

-5 minutes needed to set in place (and even then).

-Moving in all directions, Diagonals and Running working perfectly.

-No pass through Walls or Sliding on ground.

-Walk speed and Running speed can be easyly edited in-game (Properties).

-Jump function with number of jumps can be changed in real time (You just unlocked the double jump).

/The jump hight not working for in-game, im sorry (if someone know how to do...).

-If the properties are not added, the script automatically use the default values.

-All the keyboard inputs can be "easyly" changed in-game , for making all the players happy .

-All the necessary instructions are include in the script (in French and English).

Downloads:

V2 (17/09/2015): https://mega.nz/#!m1cRlDIC!wrD1ovEznhxLGssZY26sndRUFv9amtsu_wVg_8VZ60Y

Please dont remove the Top Header.

Original link:
http://blenderartists.org/forum/showthread.php?381505-FR-EN-Advanced-Moving-Script-for-the-BGE-V2-0


i do exactly what you say, and it works. Just download the latest 2.8 build


Audio/Video out of sync in rendered video, but not in VSE

I was asked to take a look at this post. Codecs can be rather puzzling to diagnose from a distance, but it does seem that some information can be offered.

  This problem seems always to pop up when then input source video is
  "mostly static", i.e. when the change from one frame to the next is
  miniscule (e.g. a screen recording). I should also add that I record
  the videos in question using a lossless codec (FRAPS or lagarith).

The “mostly static” comment here is interesting. This does indeed sound like an I versus P / B frame issue, as the “mostly static” frames would be subject to many more instances of P / B frames. While I am unfamiliar with Lagarith or FRAPS, I would be extremely surprised if a non-GOP codec had this issue, as your solution hints toward.

  Why can Blender (or its version of libavcodec) apparently correctly
  decode and show the video in the VSE, but not render it correctly? Is
  the decoding in the VSE done differently than in rendering?

The VSE is using certain techniques to display the video that, when decoded on a shot by shot basis for rendering are different. This is why non-GOP codecs are more robust, or time code indices will yield more consistent results. This is also why most always-online NLEs will transcode upon ingestion; to avoid the codec problems as well as try to reduce the always-online image degradation issues.

  What version of libavcodec is used in Blender 2.74? Is the
  implementation of e.g. lagarith faulty in this version? If not, then
  why does Blender mess up the rendering?

FFMPEG's version was a bit nasty on some platforms as it previously used a bundled version on some while on others it used a local version. If you check the ffcompat code, you can see many version checks to support generic versions of FFMPEG.

  It has been suggested that one should use "Blender-friendly" codecs
  for compression. Which lossless codecs are known to be so?

The easiest way to avoid all of the codec mess is to rely on still frame intermediates. If you must for whatever reason rely on codecs, you are likely going to be constantly faced with these sorts of issues unless you manage to coax one of the codecs to behave under generated timecode indices. I would also speculate that FFv1 should be a reasonable choice to test and put under duress, given the nature of its design. If you try FFv1, it would be interesting if you reported your results back here for future reference.

Best of luck.


Newbie Modeler Question: How to unbend a character arm before rigging

The character may have been modeled that way and in that case there's not much you can do without deforming the mesh in some way to get it to be in a T pose.


The blender program starts with a blurry interface

[For a new visitor to this page for the same problem ] Try installing 2.79 it will support your required plugin for which you are trying to install an older version and also won't give blurry effect on the interface. (Answered based on my personal experience with the same problem.)


Python render script different outcome when run in background

Rendering of viewer nodes and previews in background mode was disabled in 2013 for speed optimization (see here). However, you can easily enable it again by modifying 2 files of the blender sources and compiling blender yourself (as described here).

In the file source/blender/compositor/operations/COM_ViewerOperation.h, line ~58:

bool isOutputOperation(bool /*rendering*/) const { if (G.background) return false; return isActiveViewerOutput();

should be changed to

bool isOutputOperation(bool /*rendering*/) const {return isActiveViewerOutput(); }

and in file source/blender/compositor/operations/COM_PreviewOperation.h, line ~48:

bool isOutputOperation(bool /*rendering*/) const { return !G.background; }

should be changed to

bool isOutputOperation(bool /*rendering*/) const { return true; }

After these changes, the pixels array gets properly updated in background mode.


How to constraint object to perspective user viewport (Not render camera)

Keep context object centered on largest viewport in screen.

The view is set up similarly to the camera, ie it looks down its $-Z$ axis.
Rotate an object to camera view
Access view orientation from python?
whereas meshes are normally $Z$ up $-Y$ forward.
The view_align method below, looks for the largest 3d view, then using its matrix aligns the context object such that it looks directly at the view, from 5 global units away.
The rest is basically the modal timer operator template, similarly to question
import bpy
from mathutils import Vector, Matrix
from bpy_extras.io_utils import axis_conversion

distance_from_view = 5

A = axis_conversion(
        from_forward='Y',
        from_up='Z',
        to_forward='-Z',
        to_up='Y').to_4x4()

def view_align(context):
    areas =  sorted(
            [
                a
                for a in context.screen.areas
                if a.type == 'VIEW_3D'
            ],
            key=lambda a : a.width * a.height
        )

    if areas:
        screen = context.screen
        ob = context.object
        mw = ob.matrix_world
        r3d = areas.pop().spaces.active.region_3d
        M = r3d.view_matrix
        V = M.inverted()
        # maintain global distance from camera
        T = Matrix.Translation(V @ Vector((0, 0, -distance_from_view)))
        # keep original transform align to view
        #T = Matrix.Translation(mw.translation)
        R = M.to_3x3().transposed().to_4x4()
        S = Matrix.Diagonal(mw.to_scale()).to_4x4()
        ob.matrix_world = T @ (R @ A) @ S

class ModalTimerOperator(bpy.types.Operator):
    """Operator which runs its self from a timer"""
    bl_idname = "wm.modal_timer_operator"
    bl_label = "Modal Timer Operator"

    _timer = None

    def modal(self, context, event):
        if event.type in {'RIGHTMOUSE', 'ESC'}:
            self.cancel(context)
            return {'CANCELLED'}

        if event.type == 'TIMER':
            view_align(context)

        return {'PASS_THROUGH'}

    def execute(self, context):
        wm = context.window_manager
        self._timer = wm.event_timer_add(0.01, window=context.window)
        wm.modal_handler_add(self)
        return {'RUNNING_MODAL'}

    def cancel(self, context):
        wm = context.window_manager
        wm.event_timer_remove(self._timer)

def register():
    bpy.utils.register_class(ModalTimerOperator)

def unregister():
    bpy.utils.unregister_class(ModalTimerOperator)

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.wm.modal_timer_operator()


Can the areas of an object in shadow be accessed in Cycles

No, this is not possible in cycles.

As a workaound, you could render a diffuse pass in a different renderlayer and then use that as the mix factor, see Is it possible to use the output of a Renderlayer in the material nodes of another RenderLayer?


You can do all of those things! Generally, it's best to render animations to a still image output. That way, you can render some, then come back to it and render more frames.

As for the resolution, it's entirely up to you. If you personally think that 720p looks good, go for it. If you plan publishing this on YouTube or putting it in a reel, you should render at 1080


At current point the answer is - no.

You can use GPU for:

Cycles rendering
Subsurf
Compositing


In this case, when a window shows 'Back to Previous', it means that you can press ctrl-up arrow and return to the non-focused layout. This view has been focused on the current active window with the ctrl-up arrow.

If you open a new file and it doesn't have the layouts liek you are used to using, sometimes you can get them back by reopening the file with 'Load UI' unchecked.


How to calculate what percentage of the area of an object appears in the render view?

In case anyone have a similar problem, I 'kinda' solved the problem using ray-cast. I basically created a for loop that generates ray-casts coming from the camera with destination to the 4 vertices that frame the jersey number. I have to perform this calculation for every object that I think might be between the camera and the body. With this approach I don't really calculate the area but it turns out that it is sufficient for my goal to know that at least one of the ray-casts intercept an object.


Coordinates of the segments of the hair particle

what is your level in Python? I mean are you able to reproduce code from Blender if this need?
I could share with you an approach for this, but more like workaround instead of direct solution,... because I can't understand the main purpose of your question.

What I understood, is that you want to control a particle hair system resolution, emitted trough vertices ...

Or you can only use the Sphere to control, removing  the previous script note property.

Hope this will help you!


How can I make two duplicated object's material's independently editable?

Go to the materials tab, and click on the number that appears next to the material's name. This will make it a single user, by duplicating the material, basically meaning that they can be edited separately.


Use Proportional Editing for whole faces not individual vertices

First you need to extrude all the faces individually.

Then select all the bottom vertices and hide them using H button to leave visible only the top faces and use proportional editing to move the faces up.

Then select all the faces, change Pivot Point to Individual Origins and scale on Z axis to zero using SZ0 buttons.

Then unhide hidden geometry with Alt+H shortcut.


Move center of radial anisotropic to center of object

You could remap center of anisotropic shading to an object (this could be an Empty); use Texture Coordinates node for that:

With that, once you move the empty, center of the anisotropic shading will move as well. Note that this can even change the axis of the shading; however controling may be not as convenient as if using Tangent node to change the axis.


As far as I know this isn't possible, use the keyboard input instead.

After pressing S for scaling use the keyboard to enter 0 (zero) to perfectly align geometry and optionaly choose an axis of alignment by pressing either X Y or Z.


Why doesn't Volumetric follow the shape of Mesh in Eevee?

Eevee's support for volumetrics is quite limited.

From the blender manual:

  Eevee’s goal is to be an interactive render engine. Some features may not be there yet or may be impossible to implement into Eevee’s architecture without compromising performance.

Read: Eevee Render Limitations

  Volumes Objects

  Object volume shaders will affect the whole bounding box of the object. The shape of the volume must be adjusted using procedural texturing inside the shader.

What that means is that the volumetric shader will always be a cube or a cuboid.

As far as I know it is meant more for haze and atmospheric effects, so volume would be used on volumetric domains, not so much in detailed meshes made of smoke or dust.

Maybe someone that actually cares for Eevee can clarify.


What is the parameter A in the RGB color

The parameter A stands for alpha, which is the transparency channel. An alpha value of zero represents full transparency and a value of 1.0 represents a fully opaque pixel. The RGB values are not affected by the alpha value.


EZ uv-mapping of generated images to sphere, but never the right direction

I found the problem the next day when the coffee was fresh and it's somewhat of an oversight, but since I found it I'll just post it here.

The Projection setting in the Image Texture node needs to actually be set to Sphere if you want to project on to a Sphere. Makes sense :).


This is the option you accidentally activated, on the render layers tab, the Views section

just disable the Views checkbox


From a comment by mr-zac

  Those are custom split normals.
  Either remove them, or uncheck AutoSmooth.


ID properties can't be displayed as checkboxes:

import bpy

def draw_func(self, context):
    layout = self.layout
    ob = context.object

    try:
        ob["myBool"]
    except (AttributeError, KeyError):
        layout.label('No ["myBool"] property.')
    else:
        layout.prop(ob, '["myBool"]', toggle=True, slider=False)

def register():
    bpy.types.OBJECT_PT_custom_props.prepend(draw_func)

def unregister():
    bpy.types.OBJECT_PT_custom_props.remove(draw_func)

if __name__ == "__main__":
    register()

They will always display as integer or floating point numbers, and also stored this way.

You need to use bpy.props.BoolProperty() for checkboxes.


Is there a simple way to straighten this line of vertices?

I think the simplest way would be to scale them along the y axis with your pivot set to "median point".

Select the vertices like you've shown in the picture then press S and then Y. Scale the vertices in and they will perfectly align. You may need to repeat these steps once or twice. Make sure proportional editing is turned off during this process.

Good luck.


Keyframed animation from csv using animation nodes

You create a loop and parse all the numbers, create an origin vector and a destination vector. Then in another loop, you use an Animate Vector Node to animate between both vectors, you subtract the parsed starting frame from the time and set the duration to the parsed duration. Use the output vector list to locate your objects and you are done. You can also cache the parsed loop for a performance boost.

Now animate and you will see the animation:

If you have an animal and you want to instance it and locate the instances, you could use the Object instancer node:

There is of course more to this, but it may be complicated for you at this stage.

Here is the file:


Fixing Non-manifold edges for 3D printing

Non-manifold geometry is geometry where an edge is shared by more than 2 faces:

This is what you should be looking for. It's easy to find using Select -> Select All by Trait -> Non Manifold

Once you find it you can fix it by deleting some unnecessary faces, or separating the edges. You could use Edge split for that:

Note that it splits  them all so you need to move one and then remerge the two you like connected(you can use Merge by Distance for that)


Optimizing Face Count by Combining Faces

The term is basically "retopology" and I'm afraid you usually do it manually.
There are some algorithms for quick&dirty retopologies for preview purposes, but those genereally tend to be targeted at organic retopology, not your issue of efficiently optimizing a mesh of any kind.

The general techniques for retopoly work on any mesh and there are plenty of tutorials around.
Typically, when retopologizing the focus is not to reduce the poly count as far as possible but to get a clean topology that can easily be subdivided without any nasty edges or artefacts while still keeping a workable polycount that is within your limits. When a mesh is supposed to be animated, the focus is on achieving a clean edgeflow that enables the mesh to bend smoothly when following the rig.

So, for most meshes, don't think too much about minimizing the face count at any cost and more about the topology itself and what topology is required for the next steps in your workflow (animating, rigging, subdividing, etc.).
If you, for whatever reason, do need to minimize the face count as far as possible without loosing the shape and the quads then I'm afraid I wouldn't know any algorithm in Blender that does that automatically.


How to combine multiple objects so adding material affects all objects?

Figured it out - needed to 'Join' all my objects rather than just have them in a family tree.


Establish a variable inside a driver expression

The driver namespace

Can add functions and constants to the driver namespace

import bpy

def func(a, b, c):
    return a * b * c

m = 9.4443299912

bpy.app.driver_namespace["f"] = func
bpy.app.driver_namespace["m"] = m

Run the script above, (copy & paste into text editor hit Run Script button,)  to make the new members available to the driver namespace. To make it autorun when file is loaded, give the text block a py extension and check the Register checkbox on RHS of text editor header

Can now consider m in a driver expression to be a named constant like pi and e.

Use in a driver expression like f(m, m, m) Can be typed directly into a field by preceding with a hash # character.  Once the expression is a driver (purple) on editing expression there is no longer a need for #.

There are a number of functions and properties etc already defined to the namespace, a sample of python console output.

>>> for k, v in bpy.app.driver_namespace.items():
...     k, v
...
('asin', <built-in function asin>)
('asinh', <built-in function asinh>)
('atan', <built-in function atan>)
...
('pi', 3.141592653589793)
('e', 2.718281828459045)
...
('f', <function func at 0x7f8f18d34c80>)
('m', 9.4443299912)
('frame', 1.0)

Where frame is the context.scene.frame_current.

EDIT: would like to see a "sub expression" driver variable type where you could do this for scalars, or using other defined variables.  Fitting everything into the scripted expression can be a PITA.


Here is how I would solve this problem.

I would convert the texture into black and white using a color ramp in the node editor, where the water is black, and the land mass is grey or white (This is because white is the value pops out, black doesn't). You might need to make slight adjustments to the color ramp. (The noise texture in the demonstration should be your final planet texture)

Next, add a mix RGB node into the node editor. Also add a noise texture into the node editor. Plug the noise texture into the bottom of the mix RGB node, and set the top color of the mix RGB node to black. it is recommended to increase the detail and scale in the noise texture.

Last but not least, add a displacement node into the node editor and plug it into the displacement of the material output. Next, plug the mix RGB color into the height of the displacement node. You might need to change the scale of the displacement node. (The strength or "height" of the displacement)

I hope this works if you try it out. There are probably other ways to do this, but this is how I'd personally do it.


turning two objects in a collection,one into edit mode and leaving on in object mode

Examining this video was an interesting exercise. I was able to get this to work as he shows, but had to watch a few times. What is curious to me is that I was able to get the needed face snapping behavior without any of the checkboxes activated that he recommends in the video, which confuses me. Just to be clear, there is nothing special about the whole Object Mode/Edit Mode situation you describe. It is true, the eye is in Object Mode while the head is in Edit Mode, but the relevant point is that the video demonstrates Face Snapping while using a checkbox called Project Individual Elements. According to the tooltip, this feature allows the snapping elements to interact with other objects. So that explains how he's able to bridge the gap between Edit Mode and Object Mode. Except that it doesn't because as I said, I was able to get it to work without the Project Individual Elements option checked. So this is a mystery to me. Maybe someone else can shed some light.
I thought I would point out that I use a different technique to get eyes and eyelids to meet, and I think it's superior (if only because it requires no vertex tweaking) to the one in the video.
I start by creating a vertex group. In Object Mode, select the eyelid geometry, then go into Edit Mode and select the inner-most edge ring for the eyelid object (highlighted in green in the pic below). This vertex group will contains only the vertices from the edge ring which defines the inner rim of the eye lid.

Next, go to the Object Data tab, and look for the Vertex Group section. Click the "+" sign to add a new group, which will be empty initially. It will be called Group by default, but you can name it whatever you want. Click Assign.

Then create a Shrinkwrap modifier for the eyelid object. In Object Mode, select the eyelid object, then click on the Modifier tab in the Properties Panel and create a new modifer. Make it a Shrinkwrap.

Point the Shrinkwrap modifier to the eye object as its target (left green arrow), and use the  Vertex Group input field to point it also to the vertex group you just created (right green arrow). If you don't use the vertex group option, the entire eyelid mesh will completely collapse against the eyeball. If you do use the vertex group option, only the inner rim will touch the eyeball. And that's exactly what you want.


How to get the meshes name from the object name

obj.name gives you the object name. obj.data.name gives you mesh name. And yes, AFAIK there can be only one mesh per object. However there can be multiple objects sharing the same mesh data block.


Increase object size/dimension across two axies, while keeping proportions

Close, but only in this case

Select these vertices/edges (you can select one group of the 8, then do Shift+G --> select similar length:

Scale along the two axes that you want in bounding box pivot mode. Then switch to individual origins and scale in the opposite direction with only these vertices selected.

Python Script

It looks like you are only wanting to move each vertex a constant distance from the center. With normal scaling from a point p, a vertex 2 meters from p will move twice as much distance as a vertex 1 meter from p. This small snippet of Python code will not do this, but rather move each vertex a constant addend, not factor, of the radius.

Note: This script scales from the object's origin. Also, you should be in object mode to run it.

import bpy
import bmesh
from math import sqrt

scale = 2  # scale variable

# prepare bmesh
mesh = bpy.context.object.data
bm = bmesh.new()
bm.from_mesh(mesh)

for v in bm.verts:
    pos = v.co.xyz

    # r = sqrt(x^2 + y^2 + z^2)
    radius = sqrt(
        pow(pos.x, 2) +
        pow(pos.y, 2) +
        pow(pos.z, 2))

    a = (radius + scale) / radius

    # modify the two axes you want
    pos.x *= a
    pos.y *= a

    # apply new position
    v.co.xyz = pos

# make the bmesh the object's mesh
bm.to_mesh(mesh)
bm.free()


Ok.  I seem to have found the problem.  The pivot point for rotations/scaling was set to 'individual origins'.  If I change it to 'active element' or 'median point' it works as I desire.  I don't quite understand why this change makes a difference, but it does.
Thanks for the input!  And if you know why this change matters, let me know!


Weight paint too sharp transition between affected areas

On another forum I finally got an answer!
The problem was that since I erased all weights from all bones to paint weights from scratch, all vertices other than the painted, had to be attached to any other bones. Basically one vertex needs to be attached to more than one bone.


Should I learn Maya because it is superior to Blender in animation?

This question might seem opinion based and therefore not suitable for this platform and I think it actually might be the case. However, I think it is possible to answer it based on facts, or maybe I should say the absence of facts that you should learn Maya instead of Blender or that one of them is superior in animation as a whole.

I can say with certainty that there are no rules or laws that would force you to learn any 3d software instead of another. Blender is free so you definitely do not have any restrictions choosing it instead of any other package. It has all the tools to make animations, and there are studios that use it even for animated feature films and they seem to be happy with Blender instead of Maya. Tangent Labs with their Next Gen is a famous great example.

I think the answer to your question is: no, you shouldn't, meaning you can but do not have to. You can choose whatever you wish.


Can I use Vertex paint with volume shaders?

Unfortunately, AFAIK this is not possible currently.

This is because the vertex colors are 2D and can't really be represented in 3D. You'll notice that the same thing happens with image textures.

Instead you could try adding the vertex colors on top the volumetrics with a transparent shader, but I'm not sure this is really what you want.


integration of blender file into webstorm?

If you want a hosted solution for presenting 3D models online you may look into services like p3d.in or Sketchfab

If you want an easy (as in GUI workflow) self hosted solution directly from inside Blender check out Blend4Web


You could do it with a circle or with Grid Fill, but it really depends on your goal, what are you supposed to do with this spiral?


There are several things going on here.

In general, to unwrap for lightmaps, the recommendation is not to make very big meshes, meaning meshes with many individual parts like your building. The only way to get decent lighting in such a scenario is to make huge lightmaps (ie 2048x2048 or even higher). Your build times in Unreal, as well as in-game memory use, will suffer.

A second thing to keep note of, is that you should always try to unwrap keeping as many parts together as possible. You seem to have created seams on all edges - this is a terrible idea for lightmaps: In the game engine, there needs to be a gap between every island (to make sure no light leaks from one island to the other). That gap will will shrink when you use higher resolution lightmaps, but it will create bad results:

you will see a seam on the surface where the edge is
with many individual islands, there will be much unused space in between the islands
with many individual islands, often they don't fit on the lightmap unless you make it very high resolution

A third thing, looking at your unwrapped image, is that it seems not everything is unwrapping properly. But it's difficult to see with so many elements on one object. Are you unwrapping with U->Unwrap?

What I would try first in this case is to unwrap with U->Smart UV Project, and set the 'island margin' to 0.5. This often gets decent results, if you're not unwrapping rounded objects (since it splits the faces based on the angle they share).

When I would consider splitting the object into smaller parts. How many, depends a lot on your scenario: will you create this house 100 times in one map? Or only once? If you're splitting the object, try to do so along the separation of materials. Separate out the roof and the road, for example. This way you don't create additional draw calls as a result of your split (the engine doesn't have to look up the roof material twice etc).

When preparing for painting, accurate unwrapping gets more important. You might have to spend time manually unwrapping the whole thing, to keep as many parts together as possible. The biggest difference with the lightmap scenario above, is that lightmaps don't suffer from seams on sharp angles, while for painting you might want to keep individual parts together - but the only way to do that I know is manually selecting edges and creating seams. Anyhow, for a complicated mesh such as yours, accurate unwrapping becomes one of the biggest headaches.

Good luck!


I made a blender cube, but the colors are grey

You most likely did not change the material's Base Color, but instead changed the Viewport Display color.
For the green color to show up in your render you need to modify the material base color itself:

In order to see the material, you need to switch to LookDev mode. Not solid mode. Click on the button in the below image:

Hope this helps.


You can do that easily with edge loops.

Option 1

Start with a circle.

Extrude it (Press E and Scale it S).

Take the outermost vertices and grab them (G) create the shape of the guitar.

Until you have the full outline of your guitar.

Create edge loops by pressing CtrlR. And dragging the mouse to the middle of the geometry.
You can choose how many edge loops you want to create.

Keep adding edge loops to refine your shape.

Option 2

Another way to do this is modeling with curves:

Add a Curve_Circle object.

In edit mode subdivide it and add an outer circle. Subdivide it and shape it to the form you need. (It's very important that your circles have the same number of control points, 8 in this example).

Make sure the fill option in your curve is set to none:

Exit edit mode and convert your curve to mesh by pressing AltC and select Mesh form Curve/Meta.

Then in edit mode select all your vertices and do bridge edge loops (press the Space Bar and type Bridge...)

Then you can do edge loop cuts with CTRLR

Note the adjustments you can do changing the factor


How to link a variable of a material to another material?

I think the easiest way to do this - is using node-groups. This is instruction:

Add a node with your parameter for roughness it will be Value node:

Select your node than press Ctrl+G. It will create a node group with output from value node:

To exit from node-group press Tab and connect node group to
roughness socket.

In N-pannel you can change name to any that you like:

And finally, in outer material nodes you can add same node-group from Add(Shift+A)->Group menu.

New node will have number near node-group name. It indicates how many copies of this node-group you use.


Object became a like a grid, how to turn it back solid?

Key Z. This will toggle between Wireframe (what you are in) and Solid view.


Even though the text in the question says that there is a "Spot Lamp", the lamp in the linked file  is set to "Sun".

Volumetrics will not work with a sun lamp.
Sun lamp is not really a lamp in the sense that it's position on the scene won't affect the lighting, it is designed to give parallel rays from an infinite distance with no fallof... Just the opposite of what is needed for volumetrics.

Other light that won't work with volumetrics is Hemi

Change the lamp to any other type of directional lamp. Point, Spot or Area will work fine.

Also keep in mind that when you deal with volume scattering or absorption the light source will not be as intense, so be ready to bring up the intensity to compensate. Depending on the amount of scattering and/or volume absorption you might need very large values.


Problem appears to have been solved in Blender 2.81a. For people who come across this, update your Blender to 2.81a. If this doesn't work, try the solution mentioned in the comments.


Why is my rendering in cycles NOT grainy at all?

what you mentioned does appear to be denoising , in the cycles render properties tab below the samples , check for the denoising properties , inside the denoising , you wil find 2 options , render and viewport denoising , render denoising is used for deoising your render , which means that the denoising will not appear in the render


Light behaves differently on different materials. So to recreate these behaviours we use Maps and so we have different workflows. Mostly they are Metallic or Specular workflow.

In specular workflow the "Specular" map defines the specular reflectivity of the material. And then the Materials are divided into 2 Categories Metals and Non Metals.

Specular Map in Metals are usually coloured which gives them the Reflective Color and there albedos are usually in greycscale.

Specular map in Non metals are usually in grey scale and the colour is defined by the albedo.

Specular and metallic workflow guide

Similar case study

The above Link will help you to clear your Concepts regarding all maps used in PBR texturing.


How to mirror a box around given point, not selection center

You can use the CtrlM mirror tool, in Object or Edit mode,  in any orientation, around any pivot-point.

Set the pivot-point .. most likely '3D Cursor', or 'Active Element'
Set the orientation .. if it's not conveniently Local, Global, or other preset, create a Custom Orientation from an edge, or two vertices. (CtrlAltSpace in 2.97, header orientation menu in 2.8)
Locate the pivot-point, by ShiftS snapping the 3D cursor to the right place, or, in Edit mode, making an appropriate vertex from your selection active)
Hit  CtrlM, and  X,Y, or Z. If the orientation is not Global, but the currently selected secondary orientation, hit the dimension twice. (XX, etc.)

You can still go into the tool region to change the orientation, after left-clicking.

In Edit mode, you can achieve the same effect by creating a Custom Orientation from ant two vertices, making your selection, setting the pivot, and hitting SXX-1


How to make edge loops parallel / equidistant?

You can achieve a reasonable accuracy with the Shrinkwrap modifier.

Make a reference surface of  a duplicate of the entire deck: no holes, you will probably need to give it a Subdivision Surface modifier (probably Simple) to make it a high-enough resolution target for projection of the deckhouse roof.
Make a vertex group of those vertices of the deckhouse you wish to conform to the reference surface
Assign a Shrinkwrap Modifier to the deckhouse, restricted to the vertex group

move the reference surface in Z until the deckhouse roof is the distance above the deck you require.

Before:

After:

The exact lengths in the result will depend on the resolutions of the source and target meshes, and the projection method in the shrinkwrap.

Depending on how you've made your model so far, you may be able to use the bottom surface of your deckhouse as a reference surface, without subdivision - in that case you could project to 'Nearest Vertex' and have a point-to point correspondence.


This is Python question in fact. First line does not get influence but gets the value of it.
You should get
c = bpy.context.object.pose.bones["Forearm.L"].constraints["IK"]

then
c.influence = 1

_ lemon


Equirectangular skyboxes: Tips for avoiding pixellation?

4096 x 2048 should be adequate resolution, but keep in mind that the focal length of the camera you use in the second scene will make a big difference.

If your second scenes' camera focal length is high, 50-200mm, it is the same as opening up your equirectangular render in photoshop and zooming in a lot. Generally, a real HDR equirectangular image photographed in the real world will be 4k-12k in width. The 4K is best for reflections and lighting and the 12k might have some use as a seen sky in the 3D render, however, backplates, which are photographs taken at the same time at the same place using a different focal length (not a fisheye for panoramas, but more like a standard FOV (35mm-85mm) are often used to replace the environment image render. That image is then lined up to the rendercam (or should I say, the rendercam is aligned to the image) and it is composited in behind the CG elements, replacing the HDRI 'sky'.  If you wanted to do that without taking a separate photograph, your equirectangular environment map would have to be above 20k (generally speaking).

tl;dr  10-35mm blender camera settings should work fine with a 4k image if rendered out at 1080p.


Duplicates Hotkey entries in Preference window?

This looks like an addon problem to me. For ⇧ ShiftQ you have entries for call menu and call pie menu. I would say you have multiple addons adding the same shortcuts, or you have more than one copy of the same addon with different filenames. It could also be an addon that does not unregister itself properly leaving the shortcuts behind after you disable it.

An install of blender includes an addons folder that contains the official addons, then there are 3 places blender looks for data files, You could have a scripts/addons and scripts/addons_contrib in each location that can contain the same addon, if the same addon uses the same filename you will get an error saying you have duplicates, but it is possible to have the same addon saved with different filnames that can register without error and create the duplicate shortcut entries.

Expanding your duplicate keyboard entries will show the operator/menu name used by the duplicate which can give you some idea as to what addons are causing the problem. If the addon is not obvious by the name, the operator or menu name used for the shortcut can be used to search through files in the above directories to find where it originated.

If the name is two words separated by a . then this should match the bl_idname of the class used -

class CLIP_PIE_marker_pie(Menu):
    # Settings for the individual markers
    bl_label = "Marker Settings"
    bl_idname = "clip.marker_pie"

If you get a name like CLIP_PIE_marker_pie then it may match the class name or only part of it (the later part most likely) in the file. This is also an indication that the addon has been disabled but has not cleaned up it's keyboard shortcuts.

After finding and removing any duplicates you may also need to disable duplicate addons and remove duplicate shortcut entries, then "Save User Settings" so they stay disabled next time you start blender. You could also use File->Load Factory Settings, re-add your personal adjustments and then Save User Settings to get a clean start.


Find and Install Current Blender Release

You Can keep the current version but it's quite useless.

There are three current builds:

the main: 2.78c that you can download from the official website under download.

  https://www.blender.org/download/ù

The last two are for advanced users they are unstable, so do not save any important file with this versions:

2.79 testbuilds (2.78.5), downloadable from here:

  http://graphicall.org/110

2.8 Testbuilds (2.8), downloadable from here:

  https://builder.blender.org/download/ under the red rectangle (2.8 project)


Changing Physics of Waving Flag in Python

I already figured this out myself. It seems like the following order of calls is successful. The trick is to perform a free_bake and then calling bake_all after changing the physics parameters:

bpy.ops.ptcache.free_bake_all()

# Increase the wind speed (default: 1000)
bpy.data.objects['Field'].field.strength = 0.0

# And bake the new simulation...
bpy.ops.ptcache.bake_all(bake=True)


You could add a solidify modifier to the sphere before the boolean modifier:

Also note that you can set the boolean modifier to Difference and use a plane as the Object, it may be easier to animate than a cube.

For this to work, the normal of the plane must be facing the sphere:

You can flip the direction of the normals by

Pressing Flip Direction in 3D view > Tool Shelf (N) > Basic > Normals
Pressing CtrlN and enabling Inside in the Redo menu (either at the bottom of the Tool Shelf, or by pressing F6).

Result:


How to bend/create nice angle without warping model

As you have V angles, you should not have modeled rectangular angles in the first place, it's better to first follow the whole shape:

Extrude:

Give it a Solidify modifier (Complex mode to give it even thickness):

Apply the modifier, round the angles with bevel operations:

Correct the topology with the knife (K to activate, Z to cut through), dissolve unwanted edge loops with CtrlX:

Give your object some Boolean modifiers in order to cut of the holes, etc:


How to make multiple pivot points on one object (BGE)

For physics simulation I suggest to use rigid body joints.

You can have multiple of them at a single object.

Be aware

at least one of the objects should be a physics object (rigid body, dynamic, soft body).
the motions can exceed the joint limits (stretched chain).


Animate the rotation of a shotgun barrel

Thats because the "Origin" of the barrel is all the way to the right of the screen. Every object has an "Origin" and it is the yellow dot that appears every time you select an object.
Here is a tutorial to explain what an origin is and how to change it. - https://www.youtube.com/watch?v=0FxrRdbk854


Why are the Cycles/BI Voronoi Procedural Textures Different?

The Voronoi Texture used by the displacement modifier is generated differently since it can also be used in the Blender Internal renderer.
The node you speak of is the Cycles texture node, a completely different engine and thus completely different parameters and code.

But yeah, I'd like to see some more procedural textures ported from BI to Cycles, particularly this Voronoi texture and the Cloud texture (which has many different algorithms to choose from, whereas Cycle's Noise texture is a simple Perlin noise if I remember right)


First method (recommended):

This one is pretty simple, you can use Z-Depth value to 'hide' layer (yellow) behind mesh.

Second method (with manual Glare control):

If you for some reason would like to hide Glare effect from the front part of the mesh you could use Mask and manually place it on your image.


Really dependent of what you want to do once the base shape is done. Above two possibilities, but both may be wrong if the afterpart (if there is) needs a different geometry.

You can 'screw' + 'boolean', starting from a single edge:

Also you can 'spin' twice + 'bridge edge loops':

Spin is more manually done: make a spin for the inner part with x steps (starting from a single vertex). Make a second spin for the outer with also x steps (starting from another single vertex). Select all and in the menu in edit mode 'Edge>Bridge edge loops'.

The resulting geometry is different as the second, more manual approach, keeps quads. Depends on what you want to do after that.


Attach geometry to other geometry without duplicating it

You hit on the first one which is using separate.

Once you move the separated object into place (you can control this with extreme accuracy if you are using snapping methods for vertices / edges in this particular case), you can use JOIN.

To use the command:

Select the pyramid textured cross.
While holding SHIFT select the extruded cross shape.
Finally CTRL + J will perform the join operation.

To clean up the operation:

TAB To enter into Edit Mode.
A To Select all Vertices.

a. NOTE: CTRL + TAB >> V if your selection mode is NOT set to Vertex.
W >> R to remove redundant vertices.


How can I improve the topology of this object

From one sub-d way of looking at it, you've got 2 curvatures to capture: the one around the hole, and the one around the cylinder. To keep the cylindrical curve even, it should consist of edges parallel to the bend, as evenly spaced as possible.
So one approach, working in the flat, before bending the piece, is to try to capture the curvature of the hole using only cuts into the lines which will be parallel to the bend...

.. also isolating the hole from the bend by making it the result of an inset: puting a rim of faces around its perimeter.
Working under  Mirror and a Subdivision modifiers, you can see the curves you will wind up with.
The rules aren't hard and fast.. you can bend the up-down lines a little, and add edges around the cylinder wherever they help you out.


How Do I Get a Material to Assign to All Faces?

The material is assigned to all the faces. The black you're seeing is the faces that aren't exposed to the light. If you were to move the lamp in your scen around you would see you have applied the material to the whole cube. My suggestion would be to use a Hemi light in Material mode, since it is an even lighting, or no light at all in Textured mode.


By default one BU = one meter.  This is a pretty reasonable size to go by as a rough guideline.

If you are modeling artistically you probably don't need to worry about units too much, but you should try to keep everything from ending up very small or very large, which could cause clipping issues in the viewport, making it difficult to work with. Though if this does happen, it's not hard to scale everything up/down.

If you are working precisely with units, then you can always set them the way you want in Properties > Scene > Units:


Prevent meshes from clipping into each other

If you are referring to what can be seen in the image below, this is called z-fighting. It is when to surfaces overlap and are in the same 3d space. This is not physically possible in the real world.

To fix this you would have to get rid of one of the overlapping surfaces.

Select the object Cube
Select the faces that are overlapping.

Delete them, x -> Faces

Final Result


Detect if any edge/edges are selected in a mesh

@classmethod
def poll( self, context ):

    #Get active object
    act_obj = context.active_object

    #Check for edit mode and mesh type
    if act_obj.mode == 'EDIT' and act_obj.type == 'MESH':

        #Get selected edges from bmesh
        me = act_obj.data
        bm = bmesh.from_edit_mesh(me)

        edges_selected = [e for e in bm.edges if e.select]

        return edges_selected


Considering you are talking about the Look of the Normal, here's what you can do -
Select the Edges you want to make them Sharper, now press Ctrl + E or go to Edge menu, Select Mark Sharp.
Now You will get the Marked edges sharp with the smoothing you applied.