1. A system comprising: a processing portion; a system memory; a graphics processing unit having a graphics memory thereon; a rendering mode analysis component stored on the system memory and executable on the processing portion to: access from system memory bitmaps rasterized from HTML; compute a weighted total of pixels in the composition intersecting pixels of other of the bitmaps, the weighting based on a transparency of any intersecting pixels from different bitmaps; and if the weighted total of pixels is greater than a direct-rendering mode threshold, then instruct the graphics processing unit to render to the graphics memory, and if the weighted total of pixels is less than or equal to the direct-rendering mode threshold, then instruct the graphics processing unit to render to the system memory without rendering to the graphics memory.