getTexCoords(int texcoord_set_index) vec2
Gets the i-th texture coordinates at the shading point, where i = texcoord_set_index.
sample2DTextureVec3(int texture_index, vec2 st) vec3
Samples the i-th texture defined in the current material, where i = texture_index is a 0-based index, at the normalised coordinates (s, t). Returns a (R, G, B) triplet, where each component will be in the range [0, 1].