The answer is using the But will any drawing routine also take special care to draw on this bitmap context because now the pixels on x and y-axis have both doubled?
The solution is that we can just do a transform, and everything will be taken care of. By doing this, any drawing routine will not need to tailor to any particular size. Moving to a point at (300, 300) will be actually moving to pixel (600, 600), but the drawing can just use (300, 300) for both a regular and Retina device. The solution is:
note that the last line, the CGContextScaleCTM is important. It does the work of making (300, 300) to be the actually pixel (600, 600) on a Retina device. The line that does the