Add BlendFunc support for MRTs under OpenGL.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2810 dfc29bdd-3216-0410-991c-e03cc46cb475

include/IVideoDriver.h

@@ -198,22 +198,27 @@ namespace video
 	{
 		IRenderTarget(ITexture* texture,
 				E_COLOR_PLANE colorMask=ECP_ALL,
-				E_BLEND_FACTOR blendFunc=EBF_ONE_MINUS_SRC_ALPHA,
+				E_BLEND_FACTOR blendFuncSrc=EBF_ONE,
+				E_BLEND_FACTOR blendFuncDst=EBF_ONE_MINUS_SRC_ALPHA,
 				bool blendEnable=false) :
 			RenderTexture(texture),
 			TargetType(ERT_RENDER_TEXTURE), ColorMask(colorMask),
-			BlendFunc(blendFunc), BlendEnable(blendFunc) {}
+			BlendFuncSrc(blendFuncSrc), BlendFuncDst(blendFuncDst),
+			BlendEnable(blendEnable) {}
 		IRenderTarget(E_RENDER_TARGET target,
 				E_COLOR_PLANE colorMask=ECP_ALL,
-				E_BLEND_FACTOR blendFunc=EBF_ONE_MINUS_SRC_ALPHA,
+				E_BLEND_FACTOR blendFuncSrc=EBF_ONE,
+				E_BLEND_FACTOR blendFuncDst=EBF_ONE_MINUS_SRC_ALPHA,
 				bool blendEnable=false) :
 			RenderTexture(0),
 			TargetType(target), ColorMask(colorMask),
-			BlendFunc(blendFunc), BlendEnable(blendEnable) {}
+			BlendFuncSrc(blendFuncSrc), BlendFuncDst(blendFuncDst),
+			BlendEnable(blendEnable) {}
 		ITexture* RenderTexture;
 		E_RENDER_TARGET TargetType:8;
 		E_COLOR_PLANE ColorMask:8;
-		E_BLEND_FACTOR BlendFunc:8;
+		E_BLEND_FACTOR BlendFuncSrc:4;
+		E_BLEND_FACTOR BlendFuncDst:4;
 		bool BlendEnable;
 	};
 

source/Irrlicht/COpenGLDriver.cpp

@@ -3442,6 +3442,10 @@ bool COpenGLDriver::setRenderTarget(const core::array<video::IRenderTarget>& tar
 				else
 					extGlDisableIndexed(GL_BLEND, i);
 			}
+			if (FeatureAvailable[IRR_AMD_draw_buffers_blend] || FeatureAvailable[IRR_ARB_draw_buffers_blend])
+			{
+				extGlBlendFuncIndexed(i, targets[i].BlendFuncSrc, targets[i].BlendFuncDst);
+			}
 			if (targets[0].TargetType==ERT_RENDER_TEXTURE)
 			{
 				GLenum attachment = GL_NONE;

source/Irrlicht/COpenGLExtensionHandler.cpp

@@ -47,7 +47,8 @@ COpenGLExtensionHandler::COpenGLExtensionHandler() :
 	pGlBufferSubDataARB(0), pGlGetBufferSubDataARB(0), pGlMapBufferARB(0), pGlUnmapBufferARB(0),
 	pGlIsBufferARB(0), pGlGetBufferParameterivARB(0), pGlGetBufferPointervARB(0),
 	pGlProvokingVertexARB(0), pGlProvokingVertexEXT(0),
-	pGlColorMaskIndexedEXT(0), pGlEnableIndexedEXT(0), pGlDisableIndexedEXT(0)
+	pGlColorMaskIndexedEXT(0), pGlEnableIndexedEXT(0), pGlDisableIndexedEXT(0),
+	pGlBlendFuncIndexedAMD(0), pGlBlendFunciARB(0)
 #endif // _IRR_OPENGL_USE_EXTPOINTER_
 {
 	for (u32 i=0; i<IRR_OpenGL_Feature_Count; ++i)
@@ -192,6 +193,8 @@ void COpenGLExtensionHandler::initExtensions(bool stencilBuffer)
 	pGlColorMaskIndexedEXT= (PFNGLCOLORMASKINDEXEDEXTPROC) wglGetProcAddress("glColorMaskIndexedEXT");
 	pGlEnableIndexedEXT= (PFNGLENABLEINDEXEDEXTPROC) wglGetProcAddress("glEnableIndexedEXT");
 	pGlDisableIndexedEXT= (PFNGLDISABLEINDEXEDEXTPROC) wglGetProcAddress("glDisableIndexedEXT");
+	pGlBlendFuncIndexedAMD= (PFNGLBLENDFUNCINDEXEDAMDPROC) wglGetProcAddress("glBlendFuncIndexedAMD");
+	pGlBlendFunciARB= (PFNGLBLENDFUNCIPROC) wglGetProcAddress("glBlendFunciARB");
 
 
 #elif defined(_IRR_COMPILE_WITH_X11_DEVICE_) || defined (_IRR_COMPILE_WITH_SDL_DEVICE_)
@@ -414,6 +417,10 @@ void COpenGLExtensionHandler::initExtensions(bool stencilBuffer)
 	IRR_OGL_LOAD_EXTENSION(reinterpret_cast<const GLubyte*>("glEnableIndexedEXT"));
 	pGlDisableIndexedEXT= (PFNGLDISABLEINDEXEDEXTPROC)
 	IRR_OGL_LOAD_EXTENSION(reinterpret_cast<const GLubyte*>("glDisableIndexedEXT"));
+	pGlBlendFuncIndexedAMD= (PFNGLBLENDFUNCINDEXEDAMDPROC)
+	IRR_OGL_LOAD_EXTENSION(reinterpret_cast<const GLubyte*>("glBlendFuncIndexedAMD"));
+	pGlBlendFunciARB= (PFNGLBLENDFUNCIPROC)
+	IRR_OGL_LOAD_EXTENSION(reinterpret_cast<const GLubyte*>("glBlendFunciARB"));
 
 	#endif // _IRR_OPENGL_USE_EXTPOINTER_
 #endif // _IRR_WINDOWS_API_
@@ -550,7 +557,7 @@ bool COpenGLExtensionHandler::queryFeature(E_VIDEO_DRIVER_FEATURE feature) const
 	case EVDF_MRT_COLOR_MASK:
 		return FeatureAvailable[IRR_EXT_draw_buffers2];
 	case EVDF_MRT_BLEND_FUNC:
-		return FeatureAvailable[IRR_ARB_draw_buffers_blend];
+		return FeatureAvailable[IRR_ARB_draw_buffers_blend] || FeatureAvailable[IRR_AMD_draw_buffers_blend];
 	default:
 		return false;
 	};

source/Irrlicht/COpenGLExtensionHandler.h

@@ -903,6 +903,7 @@ class COpenGLExtensionHandler
 	void extGlColorMaskIndexed(GLuint buf, GLboolean r, GLboolean g, GLboolean b, GLboolean a);
 	void extGlEnableIndexed(GLenum target, GLuint index);
 	void extGlDisableIndexed(GLenum target, GLuint index);
+	void extGlBlendFuncIndexed(GLuint buf, GLenum src, GLenum dst);
 
 
 	protected:
@@ -976,6 +977,8 @@ class COpenGLExtensionHandler
 		PFNGLCOLORMASKINDEXEDEXTPROC pGlColorMaskIndexedEXT;
 		PFNGLENABLEINDEXEDEXTPROC pGlEnableIndexedEXT;
 		PFNGLDISABLEINDEXEDEXTPROC pGlDisableIndexedEXT;
+		PFNGLBLENDFUNCINDEXEDAMDPROC pGlBlendFuncIndexedAMD;
+		PFNGLBLENDFUNCIPROC pGlBlendFunciARB;
 	#endif
 };
 
@@ -1726,6 +1729,23 @@ inline void COpenGLExtensionHandler::extGlDisableIndexed(GLenum target, GLuint i
 }
 
 
+inline void COpenGLExtensionHandler::extGlBlendFuncIndexed(GLuint buf, GLenum src, GLenum dst)
+{
+#ifdef _IRR_OPENGL_USE_EXTPOINTER_
+	if (FeatureAvailable[IRR_ARB_draw_buffers_blend] && pGlBlendFunciARB)
+		pGlBlendFunciARB(buf, src, dst);
+	if (FeatureAvailable[IRR_AMD_draw_buffers_blend] && pGlBlendFuncIndexedAMD)
+		pGlBlendFuncIndexedAMD(buf, src, dst);
+#elif defined(GL_ARB_draw_buffers_blend)
+	glBlendFunciARB(buf, src, dst);
+#elif defined(GL_AMD_draw_buffers_blend)
+	glBlendFuncIndexedAMD(buf, src, dst);
+#else
+	os::Printer::log("glBlendFuncIndexed not supported", ELL_ERROR);
+#endif
+}
+
+
 }
 }