irr: Add support for some RG texture formats

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@13628 178a84e3-b1eb-0310-8ba1-8eac791a3b58

lib/irrlicht/changes.stk

@@ -11,3 +11,4 @@ The following changes have been made:
 - texture override
 - non-triangle VBO support
 - extension order mismatch
+- support for some RG texture formats

lib/irrlicht/include/IImage.h

@@ -111,6 +111,14 @@ public:
 			return 24;
 		case ECF_A8R8G8B8:
 			return 32;
+		case ECF_R8:
+			return 8;
+		case ECF_R8G8:
+			return 16;
+		case ECF_R16:
+			return 16;
+		case ECF_R16G16:
+			return 32;
 		case ECF_R16F:
 			return 16;
 		case ECF_G16R16F:

lib/irrlicht/include/SColor.h

@@ -31,6 +31,12 @@ namespace video
 		//! Default 32 bit color format. 8 bits are used for every component: red, green, blue and alpha.
 		ECF_A8R8G8B8,
 
+		//! The normalized non-float formats from the _rg extension
+		ECF_R8,
+		ECF_R8G8,
+		ECF_R16,
+		ECF_R16G16,
+
 		/** Floating Point formats. The following formats may only be used for render target textures. */
 
 		//! 16 bit floating point format using 16 bits for the red channel.

lib/irrlicht/source/Irrlicht/COpenGLDriver.cpp

@@ -4425,6 +4425,23 @@ IImage* COpenGLDriver::createScreenShot(video::ECOLOR_FORMAT format, video::E_RE
 		else
 			type = GL_UNSIGNED_BYTE;
 		break;
+	case ECF_R8G8:
+		// GL_ARB_texture_rg is considered always available in headers. No ifdefs.
+		fmt = GL_RG;
+		type = GL_UNSIGNED_BYTE;
+		break;
+	case ECF_R16G16:
+		fmt = GL_RG;
+		type = GL_UNSIGNED_SHORT;
+		break;
+	case ECF_R8:
+		fmt = GL_RED;
+		type = GL_UNSIGNED_BYTE;
+		break;
+	case ECF_R16:
+		fmt = GL_RED;
+		type = GL_UNSIGNED_SHORT;
+		break;
 	case ECF_R16F:
 		if (FeatureAvailable[IRR_ARB_texture_rg])
 			fmt = GL_RED;

lib/irrlicht/source/Irrlicht/COpenGLTexture.cpp

@@ -159,6 +159,28 @@ GLint COpenGLTexture::getOpenGLFormatAndParametersFromColorFormat(ECOLOR_FORMAT
 				type=GL_UNSIGNED_INT_8_8_8_8_REV;
 			internalformat =  GL_RGBA;
 			break;
+		// _rg formats.
+		case ECF_R8:
+			colorformat = GL_RED;
+			type = GL_UNSIGNED_BYTE;
+			internalformat = GL_R8;
+			break;
+		case ECF_R16:
+			colorformat = GL_RED;
+			type = GL_UNSIGNED_SHORT;
+			internalformat = GL_R16;
+			break;
+		case ECF_R8G8:
+			colorformat = GL_RG;
+			type = GL_UNSIGNED_BYTE;
+			internalformat = GL_RG8;
+			break;
+		case ECF_R16G16:
+			colorformat = GL_RG;
+			type = GL_UNSIGNED_SHORT;
+			internalformat = GL_RG16;
+			break;
+
 		// Floating Point texture formats. Thanks to Patryk "Nadro" Nadrowski.
 		case ECF_R16F:
 		{