[gs-cvs] rev 8057 - trunk/gs/src

[tim at ghostscript.com]

Author: tim
Date: 2007-06-18 08:20:47 -0700 (Mon, 18 Jun 2007)
New Revision: 8057

Modified:
   trunk/gs/src/gsdparam.c
Log:
Changing from using log10(x) / Log10(2) to iLog2(x) to compute the base 2 log.

DETAILS:

Making change to conform to gs style.

EXPECTED DIFFERENCES:

None:



Modified: trunk/gs/src/gsdparam.c
===================================================================
--- trunk/gs/src/gsdparam.c	2007-06-18 06:37:58 UTC (rev 8056)
+++ trunk/gs/src/gsdparam.c	2007-06-18 15:20:47 UTC (rev 8057)
@@ -21,7 +21,6 @@
 #include "gsparam.h"
 #include "gxdevice.h"
 #include "gxfixed.h"
-#include "math.h"			/* for log10 */
 
 /* Define whether we accept PageSize as a synonym for MediaSize. */
 /* This is for backward compatibility only. */
@@ -807,7 +806,7 @@
     dev->color_info.anti_alias.text_bits =
     	param_normalize_anti_alias_bits(dev->color_info.max_gray, tab);
     dev->color_info.anti_alias.graphics_bits =
-    	param_normalize_anti_alias_bits(dev->color_info.max_gray, gab);;
+    	param_normalize_anti_alias_bits(dev->color_info.max_gray, gab);
     dev->LockSafetyParams = locksafe;
     gx_device_decache_colors(dev);
     return 0;
@@ -827,12 +826,9 @@
 private int
 param_normalize_anti_alias_bits( uint max_gray, int bits )
 {
-	/* Use log2(x) = log10(x) / Log10(2) as log2 might not be available
-	 * with all compilers
-	 */
-	double	max_bits = log10((double)max_gray + 1.0) / 0.30102999;
+	int	max_bits = ilog2( max_gray + 1.0);
 	
-	return  (bits > max_bits ? (int)max_bits : bits);
+	return  (bits > max_bits ? max_bits : bits);
 }
 
 /* Read TextAlphaBits or GraphicsAlphaBits. */