Add rationale in the README?

[bfops]

I'm having some trouble understanding the need for this repo. I found this, but as far as I know, OpenGL texture units that solve this problem. Can somebody clarify this for me?

Thanks!

Edit: Oh this makes sense if there's a backend being supported that doesn't support texture units. Are there other use cases I'm missing?

[bvssvni]

Yeah, the idea is to have implementations of the algorithms.

Where can I find more information about OpenGL texture units?

[bfops]

https://www.opengl.org/wiki/Texture#Texture_image_units and http://stackoverflow.com/questions/25373634/opengl-rendering-with-multiple-textures?noredirect=1#comment39595524_25373634 are both a good basis.

Each sampler in a shader is bound to a specific texture unit (e.g. GL_TEXTURE0), not a specific target (e.g. GL_TEXTURE2D), so you can do something like:

glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE2D, tex1);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE2D, tex2);
glUniform1i(tex1_loc, 0);
glUniform1i(tex2_loc, 1);

and then both your textures will be available inside the shader.

Looking into it a little further though, it looks like the number of texture units can be pretty limited (e.g. 32), so it doesn't scale nearly as well as sprite sheets created with this repo.

[kvark]

Texture atlas is an old and well-known technique, still used in production, albeit much less than before.
Binding many small textures is just slower than binding a single atlas.

I do agree though that the rationale needs to be a part of README.

[simnalamburt]

Good idea. This repo can always accept more PRs.