big changes here:

- Eliminate the useless check for cpu modifications option from efb to ram as it must be enabled always
- use constant names in dx11 for buffer length calculation instead to simplify code reading
- implemented scaled efb copy in opengl, still bugy in some games, the option is not in the gui but will add it when it works perfect
- Change the depth calculation behavior:
if the game use z textures is exactly the same as before.
if the game do not use z texture calculate z values in the vertex shader. the advantage id this approach is that early z culling is applied,
improving fill rate. this mus speed up things, even with ssaa and msaa enabled.
please test for regression and enjoy.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@5896 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Plugins/Plugin_VideoDX9/Src/PixelShaderCache.cpp

@@ -266,7 +266,7 @@ void PixelShaderCache::Clear()
 		iter->second.Destroy();
 	PixelShaders.clear(); 
 
-	for (int i = 0; i < (C_COLORMATRIX + 16) * 4; i++)
+	for (int i = 0; i < C_PENVCONST_END * 4; i++)
 		lastPSconstants[i / 4][i % 4] = -100000000.0f;
 	memset(&last_pixel_shader_uid, 0xFF, sizeof(last_pixel_shader_uid));
 }