Drawing Dots and Lines
In the first chapter, I discussed how the Windows Graphics Device Interface makes use of device drivers for the graphics output devices attached to your computer. In theory, all that a graphics device driver needs for drawing is a SetPixel function and a GetPixel function. Everything else could be handled with higher-level routines implemented in the GDI module. Drawing a line, for instance, simply requires that GDI call the SetPixel routine numerous times, adjusting the x- and y-coordinates appropriately.
In reality, you can indeed do almost any drawing you need with only SetPixel and GetPixel functions. You can also design a neat and well-structured graphics programming system on top of these functions. The only problem ...
Get Programming Windows®, Fifth Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
