Added better support for OpenGL clamp modes.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@693 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/COpenGLDriver.cpp

@@ -1406,13 +1406,55 @@ void COpenGLDriver::setBasicRenderStates(const SMaterial& material, const SMater
 					mode=GL_CLAMP;
 					break;
 				case ETC_CLAMP_TO_EDGE:
-					mode=GL_CLAMP_TO_EDGE;
+#ifdef GL_VERSION_1_2
+					if (Version>101)
+						mode=GL_CLAMP_TO_EDGE;
+					else
+#endif
+#ifdef GL_SGIS_texture_edge_clamp
+					if (FeatureAvailable[IRR_SGIS_texture_edge_clamp])
+						mode=GL_CLAMP_TO_EDGE_SGIS;
+					else
+#endif
+						// fallback
+						mode=GL_CLAMP;
 					break;
 				case ETC_CLAMP_TO_BORDER:
-					mode=GL_CLAMP_TO_BORDER;
+#ifdef GL_VERSION_1_3
+					if (Version>102)
+						mode=GL_CLAMP_TO_BORDER;
+					else
+#endif
+#ifdef GL_ARB_texture_border_clamp
+					if (FeatureAvailable[IRR_ARB_texture_border_clamp])
+						mode=GL_CLAMP_TO_BORDER_ARB;
+					else
+#endif
+#ifdef GL_SGIS_texture_border_clamp
+					if (FeatureAvailable[IRR_SGIS_texture_border_clamp])
+						mode=GL_CLAMP_TO_BORDER_SGIS;
+					else
+#endif
+						// fallback
+						mode=GL_CLAMP_TO_EDGE;
 					break;
 				case ETC_MIRROR:
-					mode=GL_MIRRORED_REPEAT;
+#ifdef GL_VERSION_1_4
+					if (Version>103)
+						mode=GL_MIRRORED_REPEAT;
+					else
+#endif
+#ifdef GL_ARB_texture_border_clamp
+					if (FeatureAvailable[IRR_ARB_texture_mirrored_repeat])
+						mode=GL_MIRRORED_REPEAT_ARB;
+					else
+#endif
+#ifdef GL_IBM_texture_mirrored_repeat
+					if (FeatureAvailable[IRR_IBM_texture_mirrored_repeat])
+						mode=GL_MIRRORED_REPEAT_IBM;
+					else
+#endif
+						mode=GL_REPEAT;
 					break;
 			}
 	

source/Irrlicht/COpenGLExtensionHandler.h

@@ -354,6 +354,7 @@ static const char* const OpenGLFeatureStrings[] = {
 
 class COpenGLExtensionHandler
 {
+	public:
 	enum EOpenGLFeatures {
 		IRR_3DFX_multisample = 0,
 		IRR_3DFX_tbuffer,
@@ -645,7 +646,6 @@ class COpenGLExtensionHandler
 		IRR_OpenGL_Feature_Count
 	};
 
-	public:
 	// constructor
 	COpenGLExtensionHandler();