Start implementation for swizzle operaators. operator+ and operator- have been added.

glm/core/_swizzle.hpp

@@ -61,9 +61,11 @@ namespace detail
         N       = number of components in the vector (e.g. 3)
         E0...3  = what index the n-th element of this swizzle refers to
     */
-    template <typename Type, typename Class, int N, int E0, int E1, int E2, int E3, int DUPLICATE_ELEMENTS>
+    template <typename Derived, typename Type, typename Class, int N, int E0, int E1, int E2, int E3, int DUPLICATE_ELEMENTS>
     struct swizzle_base
     {
+        typedef Derived     derived_type;
+
         swizzle_base& operator= (const Class& that)
         {
             static const int offset_dst[4] = { E0, E1, E2, E3 };
@@ -88,101 +90,136 @@ namespace detail
         }
 
     protected:
-        Type&   elem   (size_t i) { return (reinterpret_cast<Type*>(_buffer))[i]; }
+        Type&         elem   (size_t i)       { return (reinterpret_cast<Type*>(_buffer))[i]; }
+        const Type&   elem   (size_t i) const { return (reinterpret_cast<const Type*>(_buffer))[i]; }
 
         // Use an opaque buffer to *ensure* the compiler doesn't call a constructor.
-        // Otherwise, a vec4 containg all swizzles might end up with 1000s of 
+        // Otherwise, a vec4 containing all swizzles might end up with 1000s of 
         // constructor calls
         char    _buffer[sizeof(Type) * N];
     };
 
-    template <typename Type, typename Class, int N, int E0, int E1, int E2, int E3>
-    struct swizzle_base<Type,Class,N,E0,E1,E2,E3,1>
+    template <typename Derived, typename Type, typename Class, int N, int E0, int E1, int E2, int E3>
+    struct swizzle_base<Derived, Type,Class,N,E0,E1,E2,E3,1>
     {
+        typedef Derived     derived_type;
+
         struct Stub {};
         swizzle_base& operator= (const Stub& that) {}
           
     protected:
-        Type&   elem   (size_t i) { return (reinterpret_cast<Type*>(_buffer))[i]; }
+        Type&         elem   (size_t i)       { return (reinterpret_cast<Type*>(_buffer))[i]; }
+        const Type&   elem   (size_t i) const { return (reinterpret_cast<const Type*>(_buffer))[i]; }
+
         char    _buffer[sizeof(Type) * N];      
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1>
-    struct swizzle2 : public swizzle_base<T,P,2,E0,E1,0,0,(E0 == E1)>
+    struct swizzle2 : public swizzle_base<swizzle2<T,P,E0,E1>, T,P,2,E0,E1,0,0,(E0 == E1)>
     {
-        using swizzle_base<T,P,2,E0,E1,0,0,(E0 == E1)>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1)); }
+        using swizzle_base<swizzle2<T,P,E0,E1>,T,P,2,E0,E1,0,0,(E0 == E1)>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1, int E2>
-    struct swizzle2_3 : public swizzle_base<T,P,2,E0,E1,E2,0,1>
+    struct swizzle2_3 : public swizzle_base<swizzle2_3<T,P,E0,E1,E2>,T,P,2,E0,E1,E2,0,1>
     {
-        using swizzle_base<T,P,2,E0,E1,E2,0,1>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1), this->elem(E2)); }
+        using swizzle_base<swizzle2_3<T,P,E0,E1,E2>,T,P,2,E0,E1,E2,0,1>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1), this->elem(E2)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1, int E2, int E3>
-    struct swizzle2_4 : public swizzle_base<T,P,2,E0,E1,E2,E3,1>
+    struct swizzle2_4 : public swizzle_base<swizzle2_4<T,P,E0,E1,E2,E3>,T,P,2,E0,E1,E2,E3,1>
     {
-        using swizzle_base<T,P,2,E0,E1,E2,E3,1>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1), this->elem(E2), this->elem(E3)); }
+        using swizzle_base<swizzle2_4<T,P,E0,E1,E2,E3>,T,P,2,E0,E1,E2,E3,1>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1), this->elem(E2), this->elem(E3)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1, int E2>
-    struct swizzle3 : public swizzle_base<T,P,3,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>
+    struct swizzle3 : public swizzle_base<swizzle3<T,P,E0,E1,E2>,T,P,3,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>
     {
-        using swizzle_base<T,P,3,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1), this->elem(E2)); }
+        using swizzle_base<swizzle3<T,P,E0,E1,E2>,T,P,3,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1), this->elem(E2)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1>
-    struct swizzle3_2 : public swizzle_base<T,P,2,E0,E1,0,0,(E0==E1)>
+    struct swizzle3_2 : public swizzle_base<swizzle3_2<T,P,E0,E1>,T,P,2,E0,E1,0,0,(E0==E1)>
     {
-        using swizzle_base<T,P,2,E0,E1,0,0,(E0==E1)>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1)); }
+        using swizzle_base<swizzle3_2<T,P,E0,E1>,T,P,2,E0,E1,0,0,(E0==E1)>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1, int E2, int E3>
-    struct swizzle3_4 : public swizzle_base<T,P,3,E0,E1,E2,E3,1>
+    struct swizzle3_4 : public swizzle_base<swizzle3_4<T,P,E0,E1,E2,E3>,T,P,3,E0,E1,E2,E3,1>
     {
-        using swizzle_base<T,P,3,E0,E1,E2,E3,1>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1), this->elem(E2), this->elem(E3)); }
+        using swizzle_base<swizzle3_4<T,P,E0,E1,E2,E3>,T,P,3,E0,E1,E2,E3,1>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1), this->elem(E2), this->elem(E3)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1, int E2, int E3>
-    struct swizzle4 : public swizzle_base<T,P,4,E0,E1,E2,E3,(E0==E1||E0==E2||E0==E3||E1==E2||E1==E3||E2==E3)>
+    struct swizzle4 : public swizzle_base<swizzle4<T,P,E0,E1,E2,E3>,T,P,4,E0,E1,E2,E3,(E0==E1||E0==E2||E0==E3||E1==E2||E1==E3||E2==E3)>
     {
-        using swizzle_base<T,P,4,E0,E1,E2,E3,(E0==E1||E0==E2||E0==E3||E1==E2||E1==E3||E2==E3)>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1), this->elem(E2), this->elem(E3)); }
+        using swizzle_base<swizzle4<T,P,E0,E1,E2,E3>,T,P,4,E0,E1,E2,E3,(E0==E1||E0==E2||E0==E3||E1==E2||E1==E3||E2==E3)>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1), this->elem(E2), this->elem(E3)); }
+        operator P () const { return cast(); }
     };
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1>
-    struct swizzle4_2 : public swizzle_base<T,P,2,E0,E1,0,0,(E0==E1)>
+    struct swizzle4_2 : public swizzle_base<swizzle4_2<T,P,E0,E1>,T,P,2,E0,E1,0,0,(E0==E1)>
     {
-        using swizzle_base<T,P,2,E0,E1,0,0,(E0==E1)>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1)); }
+        using swizzle_base<swizzle4_2<T,P,E0,E1>,T,P,2,E0,E1,0,0,(E0==E1)>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1)); }
+        operator P () const { return cast(); }
     };
 
 
     //! Internal class for implementing swizzle operators
     template <typename T, typename P, int E0, int E1, int E2>
-    struct swizzle4_3 : public swizzle_base<T,P,4,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>
+    struct swizzle4_3 : public swizzle_base<swizzle4_3<T,P,E0,E1,E2>,T,P,4,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>
     {
-        using swizzle_base<T,P,4,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>::operator=;
-        operator P () { return P(this->elem(E0), this->elem(E1), this->elem(E2)); }
+        using swizzle_base<swizzle4_3<T,P,E0,E1,E2>,T,P,4,E0,E1,E2,0,(E0==E1||E0==E2||E1==E2)>::operator=;
+        P cast() const { return P(this->elem(E0), this->elem(E1), this->elem(E2)); }
+        operator P () { return cast(); }
     };
 
+
+
+    template <typename T, typename P, int N, typename S0, int E0, int E1, int E2, int E3, int D0, typename S1,int F0, int F1, int F2, int F3, int D1>
+    typename P operator+ (
+        const glm::detail::swizzle_base<S0,T,P,N,E0,E1,E2,E3,D0>& a, 
+        const glm::detail::swizzle_base<S1,T,P,N,F0,F1,F2,F3,D1>& b)
+    {
+        return static_cast<const S0&>(a).cast() + static_cast<const S1&>(b).cast();
+    }
+
+    template <typename T, typename P, int N, typename S0, int E0, int E1, int E2, int E3, int D0, typename S1,int F0, int F1, int F2, int F3, int D1>
+    typename P operator- (
+        const glm::detail::swizzle_base<S0,T,P,N,E0,E1,E2,E3,D0>& a, 
+        const glm::detail::swizzle_base<S1,T,P,N,F0,F1,F2,F3,D1>& b)
+    {
+        return static_cast<const S0&>(a).cast() - static_cast<const S1&>(b).cast();
+    }
+
 }//namespace detail 
 }//namespace glm
 
+
+
+
 #define _GLM_SWIZZLE2_2_MEMBERS(T,P,E0,E1) \
     struct { glm::detail::swizzle2<T,P,0,0> E0 ## E0; }; \
     struct { glm::detail::swizzle2<T,P,0,1> E0 ## E1; }; \

test/core/core_type_vec3.cpp

@@ -103,30 +103,20 @@ int test_vec3_swizzle3_3()
     glm::vec3 v(1, 2, 3);
     glm::vec3 u;
     
-    u = v;
-    Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
+    u = v;          Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
     
-    u = v.xyz;
-    Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
-    u = v.zyx;
-    Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
-    u.zyx = v;
-    Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
-    
-    u = v.rgb;
-    Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
-    u = v.bgr;
-    Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
-    u.bgr = v;
-    Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
-
-    u = v.stp;
-    Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
-    u = v.pts;
-    Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
-    u.pts = v;
-    Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
+    u = v.xyz;      Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
+    u = v.zyx;      Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
+    u.zyx = v;      Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
     
+    u = v.rgb;      Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
+    u = v.bgr;      Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
+    u.bgr = v;      Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
+
+    u = v.stp;      Error += (u.x == 1.0f && u.y == 2.0f && u.z == 3.0f) ? 0 : 1;
+    u = v.pts;      Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
+    u.pts = v;      Error += (u.x == 3.0f && u.y == 2.0f && u.z == 1.0f) ? 0 : 1;
+   
     return Error;
 }
 
@@ -140,12 +130,8 @@ int test_vec3_swizzle_half()
     glm::hvec3 v(a1, b1, c1);
     glm::hvec3 u;
 
-    float c = v.x;
-    float d = v.y;
     u = v;
 
-    float a = u.x;
-    float b = u.y;
     Error += (u.x.toFloat() == 1.0f && u.y.toFloat() == 2.0f && u.z.toFloat() == 3.0f) ? 0 : 1;
     
     u = v.xyz;
@@ -172,6 +158,22 @@ int test_vec3_swizzle_half()
     return Error;
 }
 
+int test_vec3_swizzle_operators()
+{
+    int Error = 0;
+
+    glm::vec3 q, u, v;
+
+    u = glm::vec3(1, 2, 3);
+    v = glm::vec3(10, 20, 30);
+
+    q = u.xyz + v.xyz;          Error += (q == (u + v)) ? 0 : 1;
+    q = (u.zyx + v.zyx).zyx;    Error += (q == (u + v)) ? 0 : 1;
+    q = (u.xyz - v.xyz);        Error += (q == (u - v)) ? 0 : 1;
+    
+    return Error;
+}
+
 int main()
 {
 	int Error = 0;
@@ -181,6 +183,7 @@ int main()
     Error += test_vec3_swizzle3_2();
     Error += test_vec3_swizzle3_3();
     Error += test_vec3_swizzle_half();
+    Error += test_vec3_swizzle_operators();
 	
 	return Error;
 }