Flexipede SCORS Clip

The SCORS package from Stromberg-Carlson for generating SC4020/BL120 magnetic tapes had a very crude clipping algorithm. If the X or Y value of the start or end of a vector to be drawn was less than zero it would be set to zero and if greater than 1023 it would be set to 1023. This is clearly shown as the flexipede leaves or arrives at the drawing area.

When the Run button is pressed a JavaScript function is invoked which in turn calls another function, UpdateAnimation() at specified intervals (24 times per second). Update animation changes the value of the class attribute of the currently visible group from frameVis to frameInvis and the next group from frameInvis to frameVis, thereby cycling through all the frames in turn. When the maximum frame count is reached the animation recycles to frame 0. Pressing the Stop button halts the animation. It turned out to be very useful in understanding the code to be able to step through the animation frame by frame (button Step) and to set a starting frame for this (number input box and button Set Start Frame).

Frame: 0