Fix OpenGL detailmap lighting bug noticed by paooolino

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@843 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/COpenGLMaterialRenderer.h

@@ -475,7 +475,7 @@ public:
 			// diffuse map
 
 			glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_EXT);
-			glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_EXT, GL_REPLACE);
+			glTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_EXT, GL_MODULATE);
 
 			if (Driver->queryFeature(EVDF_MULTITEXTURE))
 			{