Reviewed-by: Jason Ekstrand <<a href="mailto:jason@jlekstrand.net">jason@jlekstrand.net</a>> <div class="gmail_quote">On Mar 23, 2016 3:40 PM, "Kenneth Graunke" <<a href="mailto:kenneth@whitecape.org">kenneth@whitecape.org</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">When using seamless cube map mode and NEAREST filtering, we explicitly overrode the wrap modes to CLAMP_TO_EDGE. This was to implement the following spec text: "If NEAREST filtering is done within a miplevel, always apply apply wrap mode CLAMP_TO_EDGE." However, textureGather() ignores the sampler's filtering mode, and instead returns the four pixels that would be blended by LINEAR filtering. This implies that we should do proper seamless filtering, and include pixels from adjacent cube faces. It turns out that we can simply delete the NEAREST -> CLAMP_TO_EDGE overrides. Normal cube map sampling works by first selecting the face, and then nearest filtering fetches the closest texel. If the nearest texel was on a different face, then that face would have been chosen. So it should always be within the face anyway, which effectively performs CLAMP_TO_EDGE. Fixes 86 dEQP-GLES31.texture.gather.basic.cube.* tests. Signed-off-by: Kenneth Graunke <<a href="mailto:kenneth@whitecape.org">kenneth@whitecape.org</a>> --- src/mesa/drivers/dri/i965/brw_sampler_state.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_sampler_state.c b/src/mesa/drivers/dri/i965/brw_sampler_state.c index c20a028..3bd22c7 100644 --- a/src/mesa/drivers/dri/i965/brw_sampler_state.c +++ b/src/mesa/drivers/dri/i965/brw_sampler_state.c @@ -460,9 +460,7 @@ brw_update_sampler_state(struct brw_context *brw, /* Cube maps must use the same wrap mode for all three coordinate * dimensions. Prior to Haswell, only CUBE and CLAMP are valid. */ - if ((tex_cube_map_seamless || sampler->CubeMapSeamless) && - (sampler->MinFilter != GL_NEAREST || - sampler->MagFilter != GL_NEAREST)) { + if (tex_cube_map_seamless || sampler->CubeMapSeamless) { wrap_s = BRW_TEXCOORDMODE_CUBE; wrap_t = BRW_TEXCOORDMODE_CUBE; wrap_r = BRW_TEXCOORDMODE_CUBE; -- 2.7.4 _______________________________________________ mesa-dev mailing list <a href="mailto:mesa-dev@lists.freedesktop.org">mesa-dev@lists.freedesktop.org</a> <a href="https://lists.freedesktop.org/mailman/listinfo/mesa-dev" rel="noreferrer" target="_blank">https://lists.freedesktop.org/mailman/listinfo/mesa-dev</a> </blockquote></div>