From: havoc <havoc@d7cf8633-e32d-0410-b094-e92efae38249>
Date: Tue, 2 Mar 2004 02:27:59 +0000 (+0000)
Subject: fix the inverted bumps on some surfaces (no longer uses CrossProduct to get the svector)
X-Git-Tag: xonotic-v0.1.0preview~6049
X-Git-Url: http://de.git.xonotic.org/?p=xonotic%2Fdarkplaces.git;a=commitdiff_plain;h=3906ee88f870a0d0f8cd95eac2c7f80c624aea86

fix the inverted bumps on some surfaces (no longer uses CrossProduct to get the svector)


git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@3953 d7cf8633-e32d-0410-b094-e92efae38249
---

diff --git a/model_shared.c b/model_shared.c
index 766ab18f..1eb8d34e 100644
--- a/model_shared.c
+++ b/model_shared.c
@@ -625,7 +625,13 @@ void Mod_BuildBumpVectors(const float *v0, const float *v1, const float *v2, con
 	f = -DotProduct(tvector3f, normal3f);
 	VectorMA(tvector3f, f, normal3f, tvector3f);
 	VectorNormalize(tvector3f);
-	CrossProduct(normal3f, tvector3f, svector3f);
+	// note: can't be a CrossProduct as that sometimes flips the texture
+	svector3f[0] = ((tc1[1] - tc0[1]) * (v2[0] - v0[0]) - (tc2[1] - tc0[1]) * (v1[0] - v0[0]));
+	svector3f[1] = ((tc1[1] - tc0[1]) * (v2[1] - v0[1]) - (tc2[1] - tc0[1]) * (v1[1] - v0[1]));
+	svector3f[2] = ((tc1[1] - tc0[1]) * (v2[2] - v0[2]) - (tc2[1] - tc0[1]) * (v1[2] - v0[2]));
+	f = -DotProduct(svector3f, normal3f);
+	VectorMA(svector3f, f, normal3f, svector3f);
+	VectorNormalize(svector3f);
 }
 
 // warning: this is an expensive function!