It is very simple, really. All you need is to bind the sampler to some texture unit with glUniform1i. So for your code sample, assuming the two uniform samplers: uniform sampler2D DecalTex; // The texture (we’ll bind to texture unit 0) uniform sampler2D BumpTex; // The bump-map (we’ll bind to texture unit 1) In your … Read more
To my knowledge there is no automatic way to calculate UV. You must calculate yourself. Calculate a UV for a plane is quite easy, this site explains how: calculating texture coordinates For a complex shape, I don’t know how. Maybe you could detect planar surface. EDIT Here is a sample code for a planar surface … Read more
This is just my two cents. Is your texture follow the isgl3D requirement? from isgl3D Tutorial 3 – Texture mapping http://isgl3d.com/tutorials/4/tutorial_3_texture_mapping For standard image files, the image size must be factor of two compliant: eg 64×128, 256×32, etc. For pvr textures, the image file must also be square: eg 64×64, 256×256, etc. Hope this help.