   glTexImage2D on same texture with different size
  Can I assume the driver will deallocate the previous texture if I call glTexImage2D a second time on a texture (with a different size) without intervening glDeleteTextures and glGenTextures?   
  yes   ;  Regardless of format changes etc.?  Anyone know where it's in the spec?  I'm looking over the spec but don't see where this is noted (glspec31.20090324.pdf)   ;  I don't know about the spec. It is just common knowledge.glTexImage2D should cause a dellocation if size and format are not the same and realloc.It is the same with all allocator functions such as glBufferData and glNewList(GL_COMPILE).;  Whether or not the internal data shall be released or not is not within the scope of the specification. It is an implementation detail how internal data is managed. The memory may, for example, be kept for future needs, so if it's not released it is kept for a reason. But just dumping any references to it within the implementation without releasing it is a memory leak, and I have enough confidence in the major driver developers to assume they're not leaking in such a common case.   