Henri Verbeet : wined3d: Handle a zero source value for WINED3DSIH_LOG.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 4a8f93baded2cc56b1154d4c2c3d8d696441bd38
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=4a8f93baded2cc56b1154d4c2c3d8d696441bd38

Author: Henri Verbeet <hverbeet at codeweavers.com>
Date:   Mon Feb  1 13:52:56 2010 +0100

wined3d: Handle a zero source value for WINED3DSIH_LOG.

---

 dlls/wined3d/glsl_shader.c |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c
index e548aca..fd359b5 100644
--- a/dlls/wined3d/glsl_shader.c
+++ b/dlls/wined3d/glsl_shader.c
@@ -2105,10 +2105,15 @@ static void shader_glsl_log(const struct wined3d_shader_instruction *ins)
 
     shader_glsl_add_src_param(ins, &ins->src[0], WINED3DSP_WRITEMASK_0, &src0_param);
 
-    if (dst_size > 1) {
-        shader_addline(buffer, "vec%d(log2(abs(%s))));\n", dst_size, src0_param.param_str);
-    } else {
-        shader_addline(buffer, "log2(abs(%s)));\n", src0_param.param_str);
+    if (dst_size > 1)
+    {
+        shader_addline(buffer, "vec%d(%s == 0.0 ? -FLT_MAX : log2(abs(%s))));\n",
+                dst_size, src0_param.param_str, src0_param.param_str);
+    }
+    else
+    {
+        shader_addline(buffer, "%s == 0.0 ? -FLT_MAX : log2(abs(%s)));\n",
+                src0_param.param_str, src0_param.param_str);
     }
 }