Centralize NPOT support check for image, export it to isSupported

src/modules/graphics/opengl/Image.cpp

@@ -278,7 +278,7 @@ namespace opengl
 
 	bool Image::loadVolatile()
 	{
-		if (GLEE_ARB_texture_non_power_of_two)
+		if (hasNpot())
 			return loadVolatileNPOT();
 		else
 			return loadVolatilePOT();
@@ -387,6 +387,11 @@ namespace opengl
 		glPopMatrix();
 	}
 
+	bool Image::hasNpot()
+	{
+		return GLEE_ARB_texture_non_power_of_two;
+	}
+
 } // opengl
 } // graphics
 } // love

src/modules/graphics/opengl/Image.h

@@ -37,7 +37,6 @@ namespace graphics
 {
 namespace opengl
 {
-
 	/**
 	* A drawable image based on OpenGL-textures. This class takes ImageData
 	* objects and create textures on the GPU for fast drawing.
@@ -138,6 +137,8 @@ namespace opengl
 		bool loadVolatile();
 		void unloadVolatile();
 
+		static bool hasNpot();
+
 	private:
 
 		void drawv(const Matrix & t, const vertex * v) const;

src/modules/graphics/opengl/wrap_Graphics.cpp

@@ -791,6 +791,10 @@ namespace opengl
 					if (!PixelEffect::isSupported())
 						supported = false;
 					break;
+				case Graphics::SUPPORT_NPOT:
+					if (!Image::hasNpot())
+						supported = false;
+					break;
 				default:
 					supported = false;
 			}