Fix a few warnings here and there, and try to use the vector classes.

src/input.cpp

@@ -57,10 +57,7 @@ float2 Input::GetAxis(int axis)
     f.x += left;
     f.y += up;
     if (left && up)
-    {
-        f.x *= invsqrt2;
-        f.y *= invsqrt2;
-    }
+        f = f * invsqrt2;
 
     return f;
 }

src/matrix.h

@@ -46,6 +46,15 @@
         return ret; \
     }
 
+#define CAST_OP(elems, dest) \
+    inline operator Vec##dest<T>() const \
+    { \
+        Vec##dest<T> ret; \
+        for (int n = 0; n < elems && n < dest; n++) \
+            ret[n] = (*this)[n]; \
+        return ret; \
+    }
+
 #define OPERATORS(elems) \
     inline T& operator[](int n) { return *(&x + n); } \
     inline T const& operator[](int n) const { return *(&x + n); } \
@@ -63,6 +72,10 @@
     SCALAR_OP(elems, *) \
     SCALAR_OP(elems, /) \
     \
+    CAST_OP(elems, 2) \
+    CAST_OP(elems, 3) \
+    CAST_OP(elems, 4) \
+    \
     template<typename U> \
     inline operator Vec##elems<U>() const \
     { \
@@ -85,6 +98,10 @@
         return sqrtf((float)sqlen()); \
     }
 
+template <typename T> struct Vec2;
+template <typename T> struct Vec3;
+template <typename T> struct Vec4;
+
 template <typename T> struct Vec2
 {
     inline Vec2() { x = y = 0; }