Changeset 1258Tweet

Timestamp:

Apr 21, 2012, 6:58:30 PM (11 years ago)

Author:

sam

Message:

math: add code to build the normal matrix from a transformation matrix.

File:

• trunk/src/lol/math/vector.h (modified) (4 diffs)

trunk/src/lol/math/vector.h

@@ -1352 +1352 @@
         v1((T)0, val) {}
 
+    explicit inline Mat2(Mat4<T> const &mat)
+      : v0(mat[0].xy),
+        v1(mat[1].xy) {}
+
     inline Vec2<T>& operator[](size_t n) { return (&v0)[n]; }
     inline Vec2<T> const& operator[](size_t n) const { return (&v0)[n]; }
@@ -1431 +1435 @@
         v2((T)0, (T)0, val) {}
 
+    explicit inline Mat3(Mat4<T> const &mat)
+      : v0(mat[0].xyz),
+        v1(mat[1].xyz),
+        v2(mat[2].xyz) {}
+
     inline Vec3<T>& operator[](size_t n) { return (&v0)[n]; }
     inline Vec3<T> const& operator[](size_t n) const { return (&v0)[n]; }
@@ -1442 +1451 @@
     {
         return rotate(angle, v) * mat;
+    }
+
+    static Mat3<T> normal(Mat3<T> const &mat)
+    {
+        return transpose(inverse(mat));
     }
 
@@ -1533 +1547 @@
     }
 
-    static Mat3<T> normal(Mat4<T> const &mat);
+    static Mat3<T> normal(Mat4<T> const &mat)
+    {
+        return transpose(inverse(Mat3<T>(mat)));
+    }
 
     /* Helpers for view matrices */