On 04/26/2013 04:52 PM, Chris Forbes wrote:
Interpolation modes other than perspective-barycentric-pixel-center (and their associated coefficients in the WM payload) only exist in Gen6 and later.Unfortunately, if a varying was declared as `centroid`, we would blindly read the nonexistant values, and so produce all manner of bad behavior -- texture swimming, snow, etc. Fixes rendering in Counter-Strike Source and Team Fortress 2 on Ironlake. Signed-off-by: Chris Forbes <chr...@ijw.co.nz> --- src/mesa/drivers/dri/i965/brw_fs.cpp | 26 +++++++++++++++++--------- 1 file changed, 17 insertions(+), 9 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index 66e78d0..1d810d8 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -984,16 +984,24 @@ fs_visitor::emit_linterp(const fs_reg &attr, const fs_reg &interp, bool is_centroid) { brw_wm_barycentric_interp_mode barycoord_mode; - if (is_centroid) { - if (interpolation_mode == INTERP_QUALIFIER_SMOOTH) - barycoord_mode = BRW_WM_PERSPECTIVE_CENTROID_BARYCENTRIC; - else - barycoord_mode = BRW_WM_NONPERSPECTIVE_CENTROID_BARYCENTRIC; + if (intel->gen >= 6) { + if (is_centroid) { + if (interpolation_mode == INTERP_QUALIFIER_SMOOTH) + barycoord_mode = BRW_WM_PERSPECTIVE_CENTROID_BARYCENTRIC; + else + barycoord_mode = BRW_WM_NONPERSPECTIVE_CENTROID_BARYCENTRIC; + } else { + if (interpolation_mode == INTERP_QUALIFIER_SMOOTH) + barycoord_mode = BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC; + else + barycoord_mode = BRW_WM_NONPERSPECTIVE_PIXEL_BARYCENTRIC; + } } else { - if (interpolation_mode == INTERP_QUALIFIER_SMOOTH) - barycoord_mode = BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC; - else - barycoord_mode = BRW_WM_NONPERSPECTIVE_PIXEL_BARYCENTRIC; + /* On Ironlake and below, there is only one interpolation mode. + * Centroid interpolation doesn't mean anything on this hardware -- + * there is no multisampling. + */ + barycoord_mode = BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC; } return emit(FS_OPCODE_LINTERP, attr, this->delta_x[barycoord_mode],
Awesome. Thanks so much for finding this! Reviewed-by: Kenneth Graunke <kenn...@whitecape.org> _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
