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+--- Thread: Fastest image refresh (/showthread.php?tid=1534)
Fastest image refresh - TerryRitchie - 03-06-2023
When using graphics, especially in games, it's often necessary to clear an image from a surface before placing another image in its place because of alpha transparency issues. The method I usually use to do this was way to slow for the current project I'm working on. So I started playing with and timing alternative methods.
Thought I would pass this tidbit of information along.
Using a 512x736 32bit image and each method repeated 10000 times I get the following.
My usual method: 0.644 seconds
Odest = _DEST
_DEST Image
CLS
_DEST Odest
Using LINE BF method: 0.620 seconds (curious that LINE is faster than CLS)
Odest = _DEST
_DEST Image
LINE(0, 0)-(_WIDTH(Image) - 1, _HEIGHT(Image) -1), _RGB32(0, 0, 0), BF
_DEST Odest
Freeing and recreating: 0.042 to 0.061 seconds (no idea why it fluctuates so much)
Iwidth = _WIDTH(Image)
Iheight = _HEIGHT(Image)
_FREEIMAGE Image
Image = _NEWIMAGE(Iwidth, Iheight, 32)
Well, as you can see, the 3rd method is superior. I created a simple subroutine to handle this for me now:
SUB RENEW_IMAGE (Image AS LONG)
DIM Iwidth AS INTEGER ' width of image
DIM Iheight AS INTEGER ' height of image
Iwidth = _WIDTH(Image) ' get width of image
Iheight = _HEIGHT(Image) ' get height of image
_FREEIMAGE Image ' remove the image from RAM
Image = _NEWIMAGE(Iwidth, Iheight, 32) ' recreate a blank surface
END SUB
RE: Fastest image refresh - SMcNeill - 03-06-2023
Even faster: use hardware images as they automatically free themselves from the display buffer after any _DISPLAY command.
RE: Fastest image refresh - TerryRitchie - 03-06-2023
(03-06-2023, 11:13 PM)SMcNeill Wrote: Even faster: use hardware images as they automatically free themselves from the display buffer after any _DISPLAY command.
I still have not had an opportunity to play with and convert this project to hardware yet.
Does this mean they clear their contents after a _DISPLAY command or need to be recreated after each _DISPLAY command?