Make the float4x4 constructor fill only the matrix's diagonal. Thus

the float4x4::identity() method is no longer necessary.

src/matrix.h

@@ -178,21 +178,19 @@ GLOBALS(4)
 template <typename T> struct Mat4
 {
     inline Mat4() { }
-    inline Mat4(T val) { for (int i = 0; i < 4; i++) v[i] = val; }
-    inline Mat4(Vec4<T> v0, Vec4<T> v1, Vec4<T> v2, Vec4<T> v3)
-        { v[0] = v0; v[1] = v1; v[2] = v2; v[3] = v3; }
-
-    inline Vec4<T>& operator[](int n) { return v[n]; }
-    inline Vec4<T> const& operator[](int n) const { return v[n]; }
-
-    static inline Mat4<T> identity()
+    inline Mat4(T val)
     {
-        Mat4<T> ret;
         for (int j = 0; j < 4; j++)
             for (int i = 0; i < 4; i++)
-                ret[i][j] = i == j;
-        return ret;
+                v[i][j] = (i == j) ? val : 0;
     }
+    inline Mat4(Vec4<T> v0, Vec4<T> v1, Vec4<T> v2, Vec4<T> v3)
+    {
+        v[0] = v0; v[1] = v1; v[2] = v2; v[3] = v3;
+    }
+
+    inline Vec4<T>& operator[](int n) { return v[n]; }
+    inline Vec4<T> const& operator[](int n) const { return v[n]; }
 
     T det() const;
     Mat4<T> invert() const;

test/matrix.cpp

@@ -32,7 +32,7 @@ public:
 
     void setUp()
     {
-        identity = float4x4::identity();
+        identity = float4x4(1.0f);
         triangular = float4x4(float4(1.0f, 0.0f, 0.0f, 0.0f),
                               float4(7.0f, 2.0f, 0.0f, 0.0f),
                               float4(1.0f, 5.0f, 3.0f, 0.0f),