diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/gen6_sf_state.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/src/mesa/drivers/dri/i965/gen6_sf_state.c b/src/mesa/drivers/dri/i965/gen6_sf_state.c index ea5c47a895f..e445ce25600 100644 --- a/src/mesa/drivers/dri/i965/gen6_sf_state.c +++ b/src/mesa/drivers/dri/i965/gen6_sf_state.c @@ -367,9 +367,25 @@ upload_sf_state(struct brw_context *brw) float line_width = roundf(CLAMP(ctx->Line.Width, 0.0, ctx->Const.MaxLineWidth)); uint32_t line_width_u3_7 = U_FIXED(line_width, 7); - /* TODO: line width of 0 is not allowed when MSAA enabled */ - if (line_width_u3_7 == 0) - line_width_u3_7 = 1; + + /* Line width of 0 is not allowed when MSAA enabled */ + if (ctx->Multisample._Enabled) { + if (line_width_u3_7 == 0) + line_width_u3_7 = 1; + } else if (ctx->Line.SmoothFlag && ctx->Line.Width < 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 section 6.3.12.1 Zero-Width (Cosmetic) Line + * Rasterization. + */ + line_width_u3_7 = 0; + } dw3 |= line_width_u3_7 << GEN6_SF_LINE_WIDTH_SHIFT; } if (ctx->Line.SmoothFlag) { |