Per Vertex Color to Texture

[shkumar]

I have a .obj mesh which has per vertex color information stored in it. There are no texture associated with this mesh.
Does someone know a method/source code/algorithm which can help me generate a texture image from per vertex color ?

[bob smith]

On Thursday, February 14, 2013 8:16:48 PM UTC-6, shkumar wrote:
> I have a .obj mesh which has per vertex color information stored in it. There are no texture associated with this mesh.
>
> Does someone know a method/source code/algorithm which can help me generate a texture image from per vertex color ?

Are you sure you need a texture image?

Most people would just turn off GL_TEXTURE and use the vertex colors without a texture when drawing.

[Linda Li]

I am just now learning GLSL. So if I am wrong, ignore my answer.

Is it possible in the fragment shader to save the color of each pixel into one block of memory and then read it out as a texture image?

On Thursday, February 14, 2013 8:16:48 PM UTC-6, shkumar wrote:

[Nobody]

On Fri, 22 Feb 2013 12:26:19 -0800, Linda Li wrote:

> I am just now learning GLSL. So if I am wrong, ignore my answer.
>
> Is it possible in the fragment shader to save the color of each pixel into
> one block of memory and then read it out as a texture image?

Saving the colour of each pixel to a block of memory is what fragment
shaders do. Framebuffer objects can be used to render into a texture, or
data can be copied from a non-texture framebuffer to a texture with
e.g. glCopyTexImage2D().

However: this requires that each face in the mesh is rendered to a
distinct set of pixels. That typically won't be the case if you render the
mesh normally. Back faces will be culled, overlapping faces will result in
only the front-most face (or portions thereof) being rendered.

Which is why the mesh has to be "unwrapped" first.