> Doing graphics in Linux is a PITA. How so? Almost every Linux distro comes with Tcl/Tk (if not installed by default, installable by checking a box in a pack

> Doing graphics in Linux is a PITA. How so? Almost every Linux distro comes with Tcl/Tk (if not installed by default, installable by checking a box in a package manager). Using the Tk canvas widget your basic code above becomes: $ wish <- start a live Tcl/Tk REPL canvas .c pack .c -expand true -fill both .c create rectangle 100 100 200 100 -fill white .c create rectangle 200 100 200 200 -fill white .c create rectangle 100 200 200 200 -fill white .c create rectangle 100 100 100 200 -fill white for {set i 100} {$i <= 200} {incr i 10} { for {set k 200} {$k <= 100} {incr k -10} { .c create rectangle $i $k $k $i -fill blue .c create rectangle $k $i $i $k -fill green } } All with the added advantage that you can watch the drawing happen as you type in the code instead of waiting until the end to enter "run". Note, I have assumed your "DRAW" statements draw rectangles because they have four coordinates. The canvas widget supports many more shapes than just basic rectangles, substitute as desired.