// All destination textures must be exactly of size <width> x <height>,
// and must either come from the same ResourcePool the effect uses, or outlive
// the EffectChain (otherwise, we could be allocating FBOs that end up being
- // stale). width and height can not be zero.
+ // stale). Textures must also have valid state; in particular, they must either
+ // be mipmap complete or have a non-mipmapped minification mode.
+ //
+ // width and height can not be zero.
struct DestinationTexture {
GLuint texnum;
GLenum format;