faster matrix inverse

git-svn-id: svn://svn.code.sf.net/p/actiongame/code/trunk/ac@4653 e016b1c5-ed68-44aa-a2f7-31cac88cffde
2009-10-06 07:21:15 +00:00
parent bf9f792a1c
commit d32f92065a
1 changed files with 3 additions and 2 deletions
@@ -701,9 +701,10 @@ void glmatrixf::adjoint(const glmatrixf &m)

 bool glmatrixf::invert(const glmatrixf &m, float mindet)
 {
-    float det = m.determinant();
-    if(fabs(det) < mindet) return false;
+    float a1 = m.v[0], b1 = m.v[4], c1 = m.v[8], d1 = m.v[12];
    adjoint(m);
+    float det = a1*v[0] + b1*v[1] + c1*v[2] + d1*v[3]; // float det = m.determinant(); 
+    if(fabs(det) < mindet) return false;
    float invdet = 1/det;
    loopi(16) v[i] *= invdet;
    return true;