From 44367aab2a987a03ee1acfb7aa3a9116f3618af0 Mon Sep 17 00:00:00 2001
From: Keith Whitwell <keith@tungstengraphics.com>
Date: Thu, 9 Jun 2005 18:59:41 +0000
Subject: Further clean up RoughApproxPow2 and disable the optimized version --
 it's a very poor approximation.

---
 src/mesa/tnl/t_vb_arbprogram.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

(limited to 'src/mesa/tnl/t_vb_arbprogram.c')

diff --git a/src/mesa/tnl/t_vb_arbprogram.c b/src/mesa/tnl/t_vb_arbprogram.c
index c569d93478..70e1048f14 100644
--- a/src/mesa/tnl/t_vb_arbprogram.c
+++ b/src/mesa/tnl/t_vb_arbprogram.c
@@ -96,16 +96,17 @@ static GLfloat RoughApproxLog2(GLfloat t)
 
 static GLfloat RoughApproxPow2(GLfloat t)
 {   
-   GLfloat q;
-#ifdef USE_IEEE
-   GLint ii = (GLint) t;
-   ii = (ii << 23) + 0x3f800000;
-   SET_FLOAT_BITS(q, ii);
-   q = *((GLfloat *) (void *)&ii);
+#if 0
+   /* This isn't nearly accurate enough - it discards all of t's
+    * fractional bits!
+    */
+   fi_type fi;
+   fi.i = (GLint) t;
+   fi.i = (fi.i << 23) + 0x3f800000;
+   return fi.f;
 #else
-   q = (GLfloat) pow(2.0, floor_t0);
+   return (GLfloat) _mesa_pow(2.0, floor_t0);
 #endif
-   return q;
 }
 
 static GLfloat RoughApproxPower(GLfloat x, GLfloat y)
-- 
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