From: Brian <brian.paul@tungstengraphics.com>
Date: Thu, 31 Jan 2008 20:37:01 +0000 (-0700)
Subject: gallium: comments about fragment Z computation
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=26fff001e786d88041d9db4c35949b50849f6a59;p=mesa.git

gallium: comments about fragment Z computation
---

diff --git a/src/mesa/pipe/softpipe/sp_quad_fs.c b/src/mesa/pipe/softpipe/sp_quad_fs.c
index c9cc8afa0ce..90691c6065d 100644
--- a/src/mesa/pipe/softpipe/sp_quad_fs.c
+++ b/src/mesa/pipe/softpipe/sp_quad_fs.c
@@ -168,6 +168,11 @@ shade_quad(
              sizeof( quad->outputs.color ) );
    }
 
+   /*
+    * XXX the following code for updating quad->outputs.depth
+    * isn't really needed if we did early z testing.
+    */
+
    /* store result Z */
    if (qss->depthOutSlot >= 0) {
       /* output[slot] is new Z */
@@ -181,6 +186,10 @@ shade_quad(
       uint i;
       for (i = 0; i < 4; i++) {
          quad->outputs.depth[i] = machine->Inputs[0].xyzw[2].f[i];
+         /* XXX not sure the above line is always correct.  The following
+          * might be better:
+         quad->outputs.depth[i] = machine->QuadPos.xyzw[2].f[i];
+          */
       }
    }