From: havoc <havoc@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Mon, 23 May 2011 15:46:32 +0000 (+0000)
Subject: added LoopingFrameNumberFromDouble function to do this operation
X-Git-Tag: xonotic-v0.6.0~163^2~383
X-Git-Url: https://git.rm.cloudns.org/?a=commitdiff_plain;h=6bb2c4cecb8a4e633fc0faf90c939fc180f7163b;p=xonotic%2Fdarkplaces.git

added LoopingFrameNumberFromDouble function to do this operation
correctly (using divide, floor, and multiply), since doing it the lazy
way (cast to int, use modulus operator) breaks down after a certain
amount of time in the level


git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11163 d7cf8633-e32d-0410-b094-e92efae38249
---

diff --git a/mathlib.c b/mathlib.c
index d6170d28..dae0de50 100644
--- a/mathlib.c
+++ b/mathlib.c
@@ -756,3 +756,12 @@ void BoxFromPoints(vec3_t mins, vec3_t maxs, int numpoints, vec_t *point3f)
 	}
 }
 
+// LordHavoc: this has to be done right or you get severe precision breakdown
+int LoopingFrameNumberFromDouble(double t, int loopframes)
+{
+	if (loopframes)
+		return (int)(t - floor(t/loopframes)*loopframes);
+	else
+		return (int)t;
+}
+
diff --git a/mathlib.h b/mathlib.h
index b3a9f7ea..e1c7f647 100644
--- a/mathlib.h
+++ b/mathlib.h
@@ -291,5 +291,7 @@ int Math_atov(const char *s, vec3_t out);
 
 void BoxFromPoints(vec3_t mins, vec3_t maxs, int numpoints, vec_t *point3f);
 
+int LoopingFrameNumberFromDouble(double t, int loopframes);
+
 #endif