[Mesa-dev] [PATCH 3/4] i965: Advertise larger line widths.

[Kenneth Graunke]

We've artificially been limiting this to 5 for no particular reason.

On Gen4-5, the limit is [0, 7.5] with a granularity of 0.5 (U3.1).
On Gen6+, the limit is [0, 7.9921875].  Since it's a U3.7, the
granularity should be 0.125 (1/8).

This patch conservatively advertises one granularity smaller than the
hardware's maximum value, just in case there's a problem using the
largest possible value.  On Gen4-5, this is 7.5 - 0.5 = 7.0.  On Gen6+,
this is 8.0 - 0.125 = 7.875.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/i965/brw_context.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_context.c b/src/mesa/drivers/dri/i965/brw_context.c
index e1a994a..eaabd43 100644
--- a/src/mesa/drivers/dri/i965/brw_context.c
+++ b/src/mesa/drivers/dri/i965/brw_context.c
@@ -421,9 +421,15 @@ brw_initialize_context_constants(struct brw_context *brw)
 
    ctx->Const.MinLineWidth = 1.0;
    ctx->Const.MinLineWidthAA = 1.0;
-   ctx->Const.MaxLineWidth = 5.0;
-   ctx->Const.MaxLineWidthAA = 5.0;
-   ctx->Const.LineWidthGranularity = 0.5;
+   if (brw->gen >= 6) {
+      ctx->Const.MaxLineWidth = 7.875;
+      ctx->Const.MaxLineWidthAA = 7.875;
+      ctx->Const.LineWidthGranularity = 0.125;
+   } else {
+      ctx->Const.MaxLineWidth = 7.0;
+      ctx->Const.MaxLineWidthAA = 7.0;
+      ctx->Const.LineWidthGranularity = 0.5;
+   }
 
    ctx->Const.MinPointSize = 1.0;
    ctx->Const.MinPointSizeAA = 1.0;
-- 
2.1.2