02-1 fastest non moving speed
I found the fastest non moving speed is about 176.47059...inche/sec or 19.75882...mph
I set pos.x+=400 to get unvisible motion of the square. And then test how many second it takes to do pos.x+=0.04, which is measured as 17 seconds. Screen is 3 inches long. So the fastest speed is (3 inches/17 secs)*1000= 176.47059...inche/sec
02-2 fastest still perceptible speed
I found the fastest still perceptible speed is about 8.3235295...inche/sec or 0.952941...mph
The fastest continuous motion happens when I set pos.x+=20. So the speed is (3 inches/17 secs)*50= 8.3235295...inche/sec
02-3 click to change pta and ptb
While the square is moving from A to B, I can click to change positionA or positionB. Here I use red to represent that A is changed to where mouse click. When it is white, B is changed.
02-4 shaper controlls something else besides position
I use the height of mouse movement to control the scale and color of the box.
02-5 multiple xenos
Here are ten small squares colored from white to black. I made the whiter squares have the faster speed to catch up with the mouse then previous ones, so it can appear on the darker ones all the time.