Systems and associated methods for processing textures in a graphical processing unit (GPU) are disclosed. Textures may be managed on a per region (e.g., tile) basis, which allows efficient use of texture memory. Moreover, very large textures may be used. Techniques provide for both texture streaming, as well as sparse textures. A GPU texture unit may be used to intelligently clamp LOD based on a shader specified value. The texture unit may provide feedback to the shader to allow the shader to react conditionally based on whether clamping was used, etc. Per region (e.g., per-tile) independent mipmap stacks may be used to allow very large textures.