From: divverent <divverent@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Thu, 11 Jun 2009 10:38:05 +0000 (+0000)
Subject: contrastboost: fix a division by zero that can never happen ;)
X-Git-Tag: xonotic-v0.1.0preview~1605
X-Git-Url: https://git.rm.cloudns.org/?a=commitdiff_plain;h=a51949900c66ac643b3e439044f692e41074144e;p=xonotic%2Fdarkplaces.git

contrastboost: fix a division by zero that can never happen ;)


git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@9017 d7cf8633-e32d-0410-b094-e92efae38249
---

diff --git a/palette.c b/palette.c
index 86ffa5a4..24ee2d00 100644
--- a/palette.c
+++ b/palette.c
@@ -173,14 +173,18 @@ void BuildGammaTable8(float prescale, float gamma, float scale, float base, floa
 {
 	int i, adjusted;
 	double invgamma;
-	double t;
+	double t, d;
 
 	invgamma = 1.0 / gamma;
 	prescale /= (double) (rampsize - 1);
 	for (i = 0;i < rampsize;i++)
 	{
 		t = i * prescale;
-		t = contrastboost * t / ((contrastboost - 1) * t + 1);
+		d = ((contrastboost - 1) * t + 1);
+		if(d == 0)
+			t = 0; // we could just as well assume 1 here, depending on which side of the division by zero we want to be
+		else
+			t = contrastboost * t / d;
 		adjusted = (int) (255.0 * (pow(t, invgamma) * scale + base) + 0.5);
 		out[i] = bound(0, adjusted, 255);
 	}