Why Use Bitmaps?
There are times when the programmer needs control over individual pixels, plus all the speed that is possible. Rendering in 3D is one case where individual pixel values are calculated using compute-intensive algorithms. Lighting calculations are performed for each pixel (often recursively) and every little coding trick eventually is used in the pursuit of speed. Pswraps is one technique available to Rhapsody developers. The “wraps” are C function calls that perform one to many PostScript operations in one interprocess message to the Window Server. So it is an efficient technique, and it is possible to write to individual pixels…sort of. For instance, one can define a rectangle with area of one pixel and the appropriate color, and draw that. This means one function call to draw each pixel. Display postscript is not really geared to individual pixel manipulation. A slightly lower level approach is to use bitmaps. A data buffer is populated dependent on various color schemes (monochrome
