   I'm a little confused about the different data types for textures...
  I'm just not really sure when to use which one... I mean, what's the difference between GL_UNSIGNED_INT and GL_UNSIGNED_INT_8_8_8_8? All this book I have tells me is that one is a packed pixel format, but that means nothing to me. Why does my app crash when I don't use the packed pixel format?   
  the only potentual for a crash is if the total number of bytes is differentim guessingGL_UNSIGNED_INT_8_8_8_8 = 8+8+8+8 = 32 bytesGL_UNSIGNED_INT * RGBA = 32*32*32*32 = 128try GL_UNSIGNED_BYTE * RGBA == 8*4 = 32byte;Quote:Original post by zedzim guessingThat would be a correct guess.For non-packed pixel formats, the type represents what datatype each color component is stored in. For a GL_UNSIGNED_INT, it means each component shall be read as a GLuint. Which, as zedz points out, turns into 32 bits per component on a usual platform.For packed pixel formats, the type represents what datatype each pixel is stored in, and the numbers represents what bits the components can be found in. For GL_UNSIGNE_INT_8_8_8_8, it means each pixel shall be read as GLuint and each component is then unpacked according to the pattern of numbers (defined in the specification).For example, GL_UNSIGNED_INT_8_8_8_8 states that a pixel is stored in a GLuint, where the first channel (first as specified by the formet, for GL_BGRA it's the B-channel) is stored in the lower 8 bits of the GLuint, and so on.   ;  Ah! Thanks, that makes sense. I assumed that the type was for each pixel and that's why I was confused.Still, it seems like GL_UNSIGNED_BYTE and GL_UNSIGNED_INT_8_8_8_8 should produce the same results... but thinks look different when blending is enabled. Still trying to figure this out...   ;  They are only the same if GLuint is little endian and 32 bits, assuming GLuchar is 8 bits. Otherwise they will behave different. For example, with 64 bit GLuint, only the lower 32 bits are used of the GLuint, and on a big endian system, the channels will appear reversed.As long as the texture is loaded identically, any difference in blending is not because of the types used.   