@ http://www.coronalabs.com/blog/2011/01/27/dynamic-image-resolution-made-easy/
says that:
The display.newImageRect() API is separate from sprite sheets, and does not affect them. This is because sprite sheets are a special case: they’re a method for conserving texture memory by allocating large shared images at the maximum possible size available on the hardware. For most mobile hardware, the largest image size is 1024 x 1024 (or 2048 x 2048 on the iPhone 4 and iPad). A sprite sheet cannot simply be doubled in size, and generally it can’t be increased in resolution at all, without exceeding the hardware limitations on many devices.
Also, due to the cruel mathematics noted above (2x resolution equals 4x memory used), a game that uses sprite sheets to push the graphics memory envelope on a low-end iPhone can’t be globally asset-doubled on the iPhone 4. Finally, Android devices have no reliable correlation between screen size and available texture memory, since these details are freely chosen by individual hardware manufacturers. There is no way to abstract away all of these hardware considerations without severely limiting you at the high end.
DOES IT MEAN we cant use dynamic scaling with sprite sheets?
Thank You.