I wrote a 774 byte program that extends the drawing functions of the calculator to include the ability to easily draw ellipses, rectangles, copy and paste, and invert selected areas of the screen. The routines used are incredibly well optimized, except that the I know I can optimize the ellipse part of the program. I checked the suggested routine in the routines section, but that code interferes with my program.
:Input :X→A :Y→B :Input :X→C :Y→D :DrawF B+√((1-(X-A)^^2^^/(C-A)^^2^^)(D-B)^^2^^ :DrawF B-√((1-(X-A)^^2^^/(C-A)^^2^^)(D-B)^^2^^
is it possible to optimize that, or somehow store the equation after B so that I can drawf B+X and B-X instead?