Movable Hole with Mask Ink

 

Compatibilities:

This item has not yet been rated

Immediately after your foreground pict in the cast, put a 1-bit picture castmember consisting of a huge black rectangle with a white circle the size of the hole you want in the middle of it. The rectangle needs to be large enough that its edges don"t start to clip the foreground pict when you move the hole all the way to the edge. Then, place foreground and background picts onstage, and set the foreground picts ink effect to "Mask". Then, place a large invisible tools palette rectangle over the two picts, and give it the following behavior

-- handler to move a hole around under mouse control -- maskCast is the cast containing the bitmap mask for the hole -- note that the stuff involving eensy is a workaround for the -- problem with stage updates not getting flushed properly: by moving -- our invisible rectangle slightly we persuade Director that the -- stage really does need updating. on mouseDown   -- save our start position   put the mouseH into oldH   put the mouseV into oldV   -- set up the stuff for the update workaround   put -1 into eensy   put the clickOn into thisSprite   -- repeatedly move the mask in line with the cursor   repeat while the mouseDown     -- get the old regPoint     put the regPoint of cast maskCast into blah     put getAt(blah,1) into regH     put getAt(blah,2) into regV     -- get the new mouse position     put the mouseV into newV     put the mouseH into newH     -- work out how much we"ve moved     set hOffset = newH - oldH     set vOffset = newV - oldV     -- move the mask regPoint the same amount in the *opposite* direction     set the regPoint of cast maskCast = point(regH-hOffset, regV-vOffset)     -- shift the foreground sprite slightly to force an update     set the locH of sprite thisSprite = the locH of sprite thisSprite + eensy     -- make it shift *back* next time around     set eensy = -eensy     -- update     updateStage     -- save the new mouse position     set oldH = newH     set oldV = newV   end repeat    -- et voila! end mouseDown