On PNV platform, for 1 pixel line thickness or less, the general anti-aliasing algorithm gives up, and a garbage line is generated. Setting a Line Width of 0.0 specifies the rasterization of the "thinnest" (one-pixel-wide), non-antialiased lines. Lines rendered with zero Line Width are rasterized using Grid Intersection Quantization rules as specified by bspec G45: Volume 2: 3D/Media, 7.3.13.1 Zero-Width (Cosmetic) Line Rasterization section.
This patch follow the same rules as patches fixing the https://bugs.freedesktop.org/show_bug.cgi?id=28832 bug. v1: Eduardo Lima Mitev: Wrong indentation inside the if clause. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=90367 Signed-off-by: Marius Predut <marius.pre...@intel.com> --- src/mesa/drivers/dri/i915/i915_state.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/src/mesa/drivers/dri/i915/i915_state.c b/src/mesa/drivers/dri/i915/i915_state.c index 4c83073..ebb4e9a 100644 --- a/src/mesa/drivers/dri/i915/i915_state.c +++ b/src/mesa/drivers/dri/i915/i915_state.c @@ -599,6 +599,21 @@ i915LineWidth(struct gl_context * ctx, GLfloat widthf) width = (int) (widthf * 2); width = CLAMP(width, 1, 0xf); + + if (ctx->Line.Width < 1.5 || widthf < 1.5) { + /* For 1 pixel line thickness or less, the general + * anti-aliasing algorithm gives up, and a garbage line is + * generated. Setting a Line Width of 0.0 specifies the + * rasterization of the "thinnest" (one-pixel-wide), + * non-antialiased lines. + * + * Lines rendered with zero Line Width are rasterized using + * Grid Intersection Quantization rules as specified by + * bspec G45: Volume 2: 3D/Media, + * 7.3.13.1 Zero-Width (Cosmetic) Line Rasterization section + */ + width = 0; + } lis4 |= width << S4_LINE_WIDTH_SHIFT; if (lis4 != i915->state.Ctx[I915_CTXREG_LIS4]) { -- 1.9.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
