Using the compositor to adjust an image that is displayed in the viewport on a mesh Alright I will try to describe the scene setup that I like to use in order to clear up what I'd like to do here.

Normally once I've baked a texture I like to continue working on the model with the texture displayed while using the Solid Viewport Shading Mode combined with GLSL Textured Solid Shading.(I've circled them in the attached image).  Usually I drop and drag the image(from the HD) onto the UV coords to set texture in the display.

Now what I'd like to be able to do is adjust the image using compositor nodes while maintaining this display setup.
So far, I can only do this if I add a material and load the texture in through there.  This also requires that I set the display mode to Rendered.  This method is slow, and requires more setup time

In the attached image you can see that I've added several different Output Nodes to see if any would affect the texture displayed in the 3D Viewport, but none do.

Does anyone know how this can be done using the more efficient Viewport Shading modes?
(btw. the selected object in the image is shaded but normally it would be in Shadeless mode while this is being done, it was a quick test.)
There is no existing internal solution for this.

However, there are still a few ways to try:

Plan A:

If you just want to adjust something like RGB Curve or Brightness/Satuation/Contrast and so on, you may consider using non-compositing adjustment directly from the Texture tab:

 

Plan B:

I think the closest way to serve such need is:


Use File Output node;
F12 to render(to output composite result);
Load that output image into UV/Image Editor, have it displayed on object (just for 3D View);
From now on, each time you want to update the composite result to 3D view, hit F12, after finishing render, hovering mouse cursor within UV/Image Editor, and press AltR to reload it (or access via Image > Reload Image).


Now, you can then see it displayed in solid/textured solid view, etc. I think this screenshot may demostrate all you need:



Tip: Delete the Render Layer node will ignore scene rendering, which will speed up the file output.

I'm sure the workflow above can be made to a single button or shortcut by scripting a bit. You just need someone that can help in trying this in coding way. (not me, yet :P) All in all, I believe anyone who knows scripts can provide a one-stop solution.