[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [32781] branches/soc-2008-mxcurioni/source /blender/freestyle/intern/system/PseudoNoise.cpp: Fix for occasional disappearance of strokes when using SpatialNoiseShader.

[Tamito Kajiyama]

Revision: 32781
          http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=32781
Author:   kjym3
Date:     2010-10-31 00:15:12 +0200 (Sun, 31 Oct 2010)

Log Message:
-----------
Fix for occasional disappearance of strokes when using SpatialNoiseShader.
The PseudoNoise class for generating a series of noise values had a bug
involving a signed integer overflow when renders were at high image resolution.
This caused the noise generator to yield very large noise values, putting
strokes out of the renders' image boundary.

Modified Paths:
--------------
    branches/soc-2008-mxcurioni/source/blender/freestyle/intern/system/PseudoNoise.cpp

Modified: branches/soc-2008-mxcurioni/source/blender/freestyle/intern/system/PseudoNoise.cpp
===================================================================
--- branches/soc-2008-mxcurioni/source/blender/freestyle/intern/system/PseudoNoise.cpp	2010-10-30 21:55:17 UTC (rev 32780)
+++ branches/soc-2008-mxcurioni/source/blender/freestyle/intern/system/PseudoNoise.cpp	2010-10-30 22:15:12 UTC (rev 32781)
@@ -43,9 +43,10 @@
 real 
 PseudoNoise::linearNoise (real x)
 {
-  int i = x*NB_VALUE_NOISE;
-  real x1=_values[i%NB_VALUE_NOISE], x2=_values[(i+1)%NB_VALUE_NOISE];
-  real t=x*real(NB_VALUE_NOISE)-real(i);
+  real tmp;
+  int i = modf(x, &tmp) * NB_VALUE_NOISE;
+  real x1=_values[i], x2=_values[(i+1)%NB_VALUE_NOISE];
+  real t = modf(x * NB_VALUE_NOISE, &tmp);
   return x1*(1-t)+x2*t;
 }
 
@@ -60,18 +61,18 @@
 real 
 PseudoNoise::smoothNoise (real x)
 {
-  int i = x*NB_VALUE_NOISE;
-  real t=x*real(NB_VALUE_NOISE)-real(i);
-  if (i - 1 < 0)
+  real tmp;
+  int i = modf(x, &tmp) * NB_VALUE_NOISE;
+  int h = i - 1;
+  if (h < 0)
     {
-      int plus=-i/NB_VALUE_NOISE;
-      i=i+NB_VALUE_NOISE*(plus+2);
-      t=(x+plus+2)*real(NB_VALUE_NOISE)-real(i);
+	  h = NB_VALUE_NOISE + h;
     }
 
-  real x1=_values[i%NB_VALUE_NOISE], x2=_values[(i+1)%NB_VALUE_NOISE];
-  real x0=_values[(i-1)%NB_VALUE_NOISE], x3=_values[(i+2)%NB_VALUE_NOISE];
+  real x1=_values[i], x2=_values[(i+1)%NB_VALUE_NOISE];
+  real x0=_values[h], x3=_values[(i+2)%NB_VALUE_NOISE];
 
+  real t = modf(x * NB_VALUE_NOISE, &tmp);
   real y0=LanczosWindowed(-1-t);
   real y1=LanczosWindowed(-t);
   real y2=LanczosWindowed(1-t);