_DEST

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The _DEST statement sets the current write image or page. All graphic and print changes will be done to this image.


Syntax

_DEST imageHandle&


Description

  • imageHandle& is the handle of the image that will act as the current write page.
  • _DEST 0 refers to the present program SCREEN. You can use 0 to refer to the present program SCREEN.
  • _DEST _CONSOLE can set the destination to send information to a console window using PRINT or INPUT.
  • If imageHandle& is an invalid handle, an invalid handle error occurs. Always check for valid handle values first (imageHandle& < -1).
  • Note: Use _SOURCE when you need to read a page or image with POINT, GET or the SCREEN function.


Examples

Example 1: Placing a center point and a circle using _CLEARCOLOR to eliminate the background color black.

SCREEN 13 'program screen can use 256 colors a& = _NEWIMAGE(320,200,13) 'create 2 screen page handles a& and b& b& = _NEWIMAGE(320,200,13) _DEST a& 'set destination image to handle a& PSET (100, 100), 15 'draw a dot on the current destination handle a& _DEST b& 'set destination image to handle b& CIRCLE (100, 100), 50, 15 'draw a circle on the current destination handle b& _CLEARCOLOR 0 'make page b color 0 (black) transparent _PUTIMAGE , b&, a& 'put circle on image b to image a& (a PSET dot) _PUTIMAGE , a&, 0 'put what is on image a& to the screen (handle 0)


Example 2: Demonstrates how printed text can be stretched using _PUTIMAGE with _DEST pages.

DIM a(10) AS LONG DIM b AS LONG REM Sets up a newimage for B then sets the screen to that. b = _NEWIMAGE(640, 480, 32) SCREEN b REM Make pages 48 pixels tall. If the image is not at least that it wont work a(1) = _NEWIMAGE(240, 48, 32) a(2) = _NEWIMAGE(240, 48, 32) a(3) = _NEWIMAGE(98, 48, 32) xa = 100 ya = 120 xm = 4 ym = 4 REM Some fun things for the bouncing text. st$(0) = "doo" st$(1) = "rey" st$(2) = "mee" st$(3) = "faa" st$(4) = "soo" st$(5) = "laa" st$(6) = "tee" sta$(0) = "This is a demo" sta$(1) = "showing how to use" sta$(2) = "the _DEST command" sta$(3) = "with PRINT" sta$(4) = "and _PUTIMAGE" REM prints to a(3) image then switches back to the default 0 _DEST a(3): f = INT(RND * 6): PRINT st$(3): _DEST 0 DO REM prints to a(1) and a(2) then switches bac to 0 _DEST a(1) CLS PRINT sta(r) _DEST a(2) CLS PRINT sta(r + 1) _DEST 0 'destination zero is the main program page REM a loop to putimage the images in a(1) and a(2) in a way to make it look like its rolling FOR yat = 150 TO 380 STEP 4 CLS _PUTIMAGE (0, yat)-(640, 380), a(1) _PUTIMAGE (0, 150)-(640, yat), a(2) GOSUB bounce _DISPLAY _LIMIT 20 NEXT yat r = r + 1 IF r = 4 THEN r = 0 LOOP UNTIL INKEY$ <> "" END bounce: IF xa > 600 OR xa < 20 THEN xm = xm * -1: _DEST a(3): f = INT(RND * 6): CLS: _CLEARCOLOR 0: PRINT st$(f): _DEST 0 IF ya > 400 OR ya < 20 THEN ym = ym * -1: _DEST a(3): f = INT(RND * 7): CLS: _CLEARCOLOR 0: PRINT st$(f): _DEST 0 _PUTIMAGE (xa, ya)-(xa + 150, ya + 80), a(3) xa = xa + xm ya = ya + ym RETURN

Adapted from code by CodeViper


See also



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