Hardware images

From QB64 Phoenix Edition Wiki
Jump to navigation Jump to search
Hardware Images (QB64 version 1.000 and up)


Demonstration of the Advantages of Using Hardware Images


The first example uses software images while using between 20 - 30% processor power:
SCREEN _NEWIMAGE(640, 480, 32)

'create some software screens
scr_bg = _NEWIMAGE(640, 480, 32)
scr_fg = _NEWIMAGE(50, 50, 32)

'draw to the background one, and make a nice pattern
_DEST scr_bg
FOR i = 1 TO 100
    LINE (RND * 640, RND * 480)-(RND * 640, RND * 480), _RGBA32(RND * 255, RND * 255, RND * 255, RND * 255), BF
NEXT i

'then do the same thing for the foreground
_DEST scr_fg
LINE (0, 0)-(50, 50), _RGBA32(255, 255, 255, 200), BF

'set image destination to main screen
_DEST 0
DO
    CLS
    _PUTIMAGE , scr_bg
    _PUTIMAGE (x, y), scr_fg
    k = _KEYHIT
    SELECT CASE k
        CASE ASC("w"): y = y - 1
        CASE ASC("a"): x = x - 1
        CASE ASC("s"): y = y + 1
        CASE ASC("d"): x = x + 1
    END SELECT
    _DISPLAY 'render image after changes
    _LIMIT 30 'we're doing all this at 30 cycles/second
LOOP
Example by Johny B.


The second example converts the foreground and background software screens to hardware using 6-7% processor power:
SCREEN _NEWIMAGE(640, 480, 32)

'create some software screens
scr_bg = _NEWIMAGE(640, 480, 32)
scr_fg = _NEWIMAGE(50, 50, 32)

'draw to the background one, and make a nice pattern
_DEST scr_bg
FOR i = 1 TO 100
    LINE (RND * 640, RND * 480)-(RND * 640, RND * 480), _RGBA32(RND * 255, RND * 255, RND * 255, RND * 255), BF
NEXT i
'create a hardware screen version of the background
scrh_bg = _COPYIMAGE(scr_bg, 33)
_FREEIMAGE scr_bg 'we no longer need the software version in memory

'then do the same thing for the foreground
_DEST scr_fg
LINE (0, 0)-(50, 50), _RGBA32(255, 255, 255, 200), BF
'copy to hardware screen
scrh_fg = _COPYIMAGE(scr_fg, 33)
_FREEIMAGE scr_fg 'and free software screen from memory

'set image destination to main screen
_DEST 0
_DISPLAYORDER _HARDWARE 'do not even render the software layer, just the hardware one.
DO 'main program loop
    '_putimage knows these are hardware screens, so destination of 0 is taken as hardware layer
    _PUTIMAGE , scrh_bg
    _PUTIMAGE (x, y), scrh_fg
    'just some input processing
    k = _KEYHIT
    SELECT CASE k
        CASE ASC("w"): y = y - 1
        CASE ASC("a"): x = x - 1
        CASE ASC("s"): y = y + 1
        CASE ASC("d"): x = x + 1
    END SELECT
    _DISPLAY 'render image after changes
    _LIMIT 30 'we're doing all this at 30 cycles/second
LOOP
Example by Johny B.


See also


QB64 Programming References

Wiki Pages
Main Page with Articles and Tutorials
QB64 specific keywords (alphabetical)
Original QBasic keywords (alphabetical)
QB64 OpenGL keywords (alphabetical)
Keywords by Usage
Got a question about something?
Frequently Asked Questions about QB64
QB64 Phoenix Edition Community Forum
Links to other QBasic Sites:
Pete's QBasic Forum
Pete's QBasic Downloads