Override the "size" of a texture:

Foo [res 128x64].png

This can be used to store a texture at a different resolution without
having to change all of the metrics that reference it.

The most obvious use is to lower the resolution of large images.

A less obvious use is to raise the resolution of images.  If an image is
going to be zoomed, it may be useful to store the texture at a higher
resolution than native.

This can be done with metrics, but it's a pain to have to track down
each metric that needs to be changed.  This (should) also work with
fonts (but that needs testing).

Use this sparingly.

stepmania/src/RageBitmapTexture.cpp

@@ -105,6 +105,23 @@ int PixFmtMaskNo(GLenum fmt)
 	}
 }
 
+static void GetResolutionFromFileName( CString sPath, int &Width, int &Height )
+{
+	/* Match:
+	 *  Foo [res 512x128].png
+	 * 
+	 * This leaves us room syntactically to do other things later, if we need to.
+	 * Be careful that this doesn't get mixed up with frame dimensions. */
+	Regex re("\\[res ([0-9]+)x([0-9]+)\\]");
+
+	vector<CString> matches;
+	if(!re.Compare(sPath, matches))
+		return;
+
+	Width = atoi(matches[0].c_str());
+	Height = atoi(matches[1].c_str());
+}
+
 //-----------------------------------------------------------------------------
 // RageBitmapTexture constructor
 //-----------------------------------------------------------------------------
@@ -277,6 +294,8 @@ SDL_Surface *RageBitmapTexture::CreateImg(int &pixfmt)
 		zoomSurface(img, m_iImageWidth, m_iImageHeight );
 	}
 
+	/* See if the apparent "size" is being overridden. */
+	GetResolutionFromFileName(m_ActualID.filename, m_iSourceWidth, m_iSourceHeight);
 	return img;
 }