3d-texture

I would like to use some 3D textures for objects that I'm rendering in WebGL. I'm currently using the following method in a fragment shader, as suggested on WebGL and OpenGL Differences : // tex is a texture with each slice of the cube placed horizontally across the texture. // texCoord is a 3d texture coord // size is the size if the cube in pixels. vec4 sampleAs3DTexture(sampler2D tex, vec3 texCoord, float size) { float sliceSize = 1.0 / size; // space of 1 slice float slicePixelSize = sliceSize / size; // space of 1 pixel float sliceInnerSize = slicePixelSize * (size - 1.0); // space of

I am trying to create a simple 3D-array visualisation in opengl. The 3D-array contains color values. To achieve this, I could just draw lots of cubes, giving them texture-coordinates to point to the correct texel. Well, I tried it, and it works. But I need a lot more, and the only way to achieve what I want is if I just draw full 2D planes on every grid in the other axis direction as the plane is on and do this is 6 directions. So for example: I draw XY-plane from -15 to +15, on Z-coordinates -15 to +15, and do this also for back-XY-plane, YZ-plane, back-YZ-plane, ... This way, I can just put