How to not allow an graphic drag through another object?

[alex298]

Hi,

I have two graphics (a ball and a wall) on a card. The user can use the mouse to drag around the card but not allow to drag across the wall.

I tried to use mousedown and drag, intersect and within. However the ball can be dragged through the wall. I studied some similar examples on the Web, they just used a beep sound to alert the intersection. The two objects can be intersected and overlapped.

I need the two objects not allow to overlap, just touching. How can I do that?

Thanks and best regards

[Mark]

Hi Alex,

The following script comes from my Snapper project <http://snapper.economy-x-talk.com>, which has a selection area that does something similar to what you need. To try this script, you'll need an object, e.g. a transparent button, containing this script and an image named "Selection". After you have figured out how this script wors, you should be able to do what you want.

Code: Select all

on mouseDown
   put the mouseLoc into myLoc
   set the cursor to cross
   repeat until the mouse is up
     put the mouseLoc into myNewLoc
     put quadrant(myLoc,myNewLoc)
     switch quadrant(myLoc,myNewLoc)
     case 1
       put item 1 of myLoc & comma & item 2 of myNewLoc into myTL
       put item 1 of myNewLoc & comma & item 2 of myLoc into myBR
       break
     case 2
       put myLoc into myBR
       put myNewLoc into myTL
       break
     case 3
       put item 1 of myLoc & comma & item 2 of myNewLoc into myBR
       put item 1 of myNewLoc & comma & item 2 of myLoc into myTL
       break
     case 4
       put myLoc into myTL
       put myNewLoc into myBR
       break
     end switch
     if item 1 of myBR > the right of me then put the right of me into item 1 of myBR
     if item 2 of myBR > the bottom of me then put the bottom of me into item 2 of myBR
     if item 1 of myTL < the left of me then put the left of me into item 1 of myTL
     if item 2 of myTL < the top of me then put the top of me into item 2 of myTL
     put myTL & comma & myBR into myRect
     if myRect is a rect then
       set the rect of grc "Selection" to (myTL & comma & myBR)
     end if
   end repeat
   set the cursor to arrow
end mouseDown

function quadrant theOldLoc,theNewLoc
   if item 1 of theNewLoc > item 1 of theOldLoc and item 2 of theNewLoc < item 2 of theOldLoc then
     return 1
   else if item 1 of theNewLoc< item 1 of theOldLoc and item 2 of theNewLoc < item 2 of theOldLoc then
     return 2
   else  if item 1 of theNewLoc < item 1 of theOldLoc and item 2 of theNewLoc > item 2 of theOldLoc then
     return 3
   else  if item 1 of theNewLoc > item 1 of theOldLoc and item 2 of theNewLoc > item 2 of theOldLoc then
     return 4
   end if
   return 0
end quadrant

Best regards,

Mark Schonewille