nitrofurano inspired me to revisit my pixel graphics
Here are the new optimizations:
the previous version draws one pixel at a time, this version draws line segments, the subprogram HLINE(X1,Y,X2,C) draws a horizontal line really fast and can be used to draw various shapes
improvements for rectangles
repeating the bit shapes vertically so that they only have to be generated once per vertical strip
it has been optimized even further by FILLing cells in the center of a shape using the FILL function
ROM data with the COPY function made it even faster
