From: Nicolai Haehnle <nhaehnle@gmail.com>
Date: Mon, 19 Mar 2007 18:45:45 +0000 (+0100)
Subject: r300: Fix WRITEMASK handling when writing to result.depth
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=c4bf863f4cb48c2de284933bb1fc725b540ee810;p=mesa.git

r300: Fix WRITEMASK handling when writing to result.depth

This is a necessary change to emit the right instructions when writing
to result.depth.

However, even with this test, Z-write doesn't work properly, and I don't
fully understand why. In addition to this, we'll at least have to disable
early-Z, but even that doesn't seem to be enough.
---

diff --git a/src/mesa/drivers/dri/r300/r300_fragprog.c b/src/mesa/drivers/dri/r300/r300_fragprog.c
index b0681e28083..fb559e880ae 100644
--- a/src/mesa/drivers/dri/r300/r300_fragprog.c
+++ b/src/mesa/drivers/dri/r300/r300_fragprog.c
@@ -1304,9 +1304,14 @@ static void emit_arith(struct r300_fragment_program *rp,
 	argc = r300_fpop[op].argc;
 
 	if (REG_GET_TYPE(dest) == REG_TYPE_OUTPUT &&
-	    REG_GET_INDEX(dest) == FRAG_RESULT_DEPR)
-		mask &= ~WRITEMASK_XYZ;
-	
+	    REG_GET_INDEX(dest) == FRAG_RESULT_DEPR) {
+		if (mask & WRITEMASK_Z) {
+			mask = WRITEMASK_W;
+		} else {
+			return;
+		}
+	}
+
 	emit_vop = GL_FALSE;
 	emit_sop = GL_FALSE;
 	if ((mask & WRITEMASK_XYZ) || vop == R300_FPI0_OUTC_DP3)