What extra features does VARPTR provide?
#3
VARPTR$ can come in handy when using DRAW or PLAY inside tight loops where you want to avoid the overhead and speed penalty of say string concatenation or other string ops.

Like in the example below, we avoid a string concatenation inside the FOR loop by using VARPTR$ for DRAW. This still works in QB64, thanks to the length Galleon went to emulate such things.

This is probably the only reason I'd use VARPTR$. Else, it is better to avoid such legacy commands.

Code: (Select All)

SCREEN 12

drawCmd$ = "TA=" + VARPTR$(angle) + "BU100"

FOR angle = 0 TO 360 STEP 30 ' 360/12 hour circles = 30 degrees apart
    PSET (175, 250), 6 ' stay at center point of clock
    DRAW drawCmd$ ' move invisibly to set next circle's center point
    CIRCLE STEP(0, 0), 5, 12 ' circle placed at end of blind line
    DRAW "P9, 12" ' paint inside of circle
    SLEEP 1 ' slowed for demo only
NEXT
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RE: What extra features does VARPTR provide? - by a740g - 06-22-2023, 01:44 PM



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