On Mon, Sep 10, 2012 at 4:49 PM, Jeff Muizelaar <[email protected]>wrote:
> > On 2012-09-10, at 3:43 PM, Vladimir Vukicevic wrote: > > > FWIW, there are also negative performance implications to clamping samples > to the source rect. Many graphics APIs do not support this kind sampling, > and supporting this behaviour on top of those apis requires a temporary > copy of the subimage to be made. > > You are referring to the fact that clamping modes only apply to texture borders in OpenGL and DirectX? That is not that big of a big deal, you can implement the clamp in a shader. I think Vladimir makes a good point that there are valid use cases for both ways. To summarize the issues: * clamping to source rect can cause filtering artefacts at boundaries, especially visible when tiling. * clamping to source image bounds can cause color bleeding artefacts when rendering a sprite from a spritemap.
