OpenEuphoria

Usemaps

• Posted by "Cuny, David" <David.Cuny at DSS.CA.GOV> Jul 20, 1998
• 717 views

Bonn wrote:

> How do I assign a part of a bitmap to a routine? (sorta like Usemaps
> in HTML) like:
>
> x = rect(240, 383, 373, 230)
> y = rect(220, 363, 353, 210)


Here's a simple (untested) example:

   sequence buttons
   buttons = {}

   procedure xPushed()
      position( 1, 1 )
      puts( 1, "X was pushed!" )
   end procedure

   procedure yPushed()
      position( 1, 1 )
      puts( 1, "Y was pushed!" )
   end procedure

   buttons = append( 240, 383, 373, 230, routine_id("xPushed") )
   buttons = append( 220, 363, 353, 210, routine_id("yPushed") )

   constant
      MouseEvent = 1
      MouseX     = 2,
      MouseY     = 3,
      X1         = 1,
      Y1         = 2,
      X2         = 3,
      Y2         = 4,
      Code       = 5

   object mouse

   -- loop forever, watching for mouse clicks
   while 1 do

      -- check the mouse
      mouse = get_mouse()

      -- mouse event?
      if sequence( mouse ) do

         -- left click?
         if and_bits( mouse[MouseEvent], LEFT_DOWN ) then

            -- check each "button"
            for i = 1 to length( buttons ) do

               -- inside a "button"?
               if  mouse[MouseX] >= buttons[i][X1]
               and mouse[MouseY] >= buttons[i][Y1]
               and mouse[MouseX] <= buttons[i][X2]
               and mouse[MouseY] >= buttons[i][Y2] then

                  -- run the code
                  call_proc( buttons[i][Code], {} )
                  -- exit loop
                  exit

               end if
            end for
         end if
      end if
   end while

If you wanted to include the *whole* bitmap, you could include create a
helper routine like this to make your life easier:

   procedure addButton( integer x, integer y, sequence bitmap, integer
id )
      integer x2, y2
      -- calculate size
      x2 = x + length( bitmap[1] )
      y2 = y + length( bitmap )
      -- add to buttons
      buttons = append( buttons,  { x, y, x2, y2, id } )
   end procedure

You could call it like this:

   addButton( 10, 20, bitmap1, routine_id( "bitmap1Pressed" ) )

The routine_id() in the function is a bit awkward, but necessary for the
moment.

Hope this helps.

-- David Cuny