Is there a faster way to do this glow circle effect?

[SMcNeill]

How about something like this:

Code: (Select All)

SCREEN _NEWIMAGE(1000, 700, 32)



'draw a background

FOR x = 0 TO _WIDTH STEP 25

    FOR y = 0 TO _HEIGHT STEP 25

        LINE (x, y)-STEP(25, 25), _RGBA(RND * 255, RND * 255, RND * 255, 150), BF

    NEXT

NEXT



'copy screen as image

back& = _COPYIMAGE(_DISPLAY)



DO



    'get mouse input

    WHILE _MOUSEINPUT: WEND

    mx = _MOUSEX: my = _MOUSEY



    'place background first

    _PUTIMAGE (0, 0), back&



    'draw fadeout circle where mouse x/y is

    FadeCircle mx, my

    _DISPLAY

    _LIMIT 30



LOOP UNTIL INKEY$ <> ""





SUB FadeCircle (mx, my)

    STATIC CircleImage, FadeScreen, wide2

    IF CircleImage = 0 THEN

        wide = 450: wide2 = wide / 2

        CircleImage = _NEWIMAGE(wide, wide, 32)

        FadeScreen = _NEWIMAGE(_WIDTH, _HEIGHT, 32)

        d = _DEST

        _DEST CircleImage

        CLS , _RGB32(0, 0, 0)

        _DONTBLEND

        FOR i = 0 TO wide2 STEP .333

            CIRCLE (wide2, wide2), i, _RGBA32(0, 0, 0, i * (255 / wide2))

        NEXT

        _DEST d

    END IF

    CLS , _RGB32(0, 0, 0), FadeScreen

    _PUTIMAGE (mx - wide2, my - wide2), CircleImage, FadeScreen

    _PUTIMAGE , FadeScreen

END SUB

Predraw the faded circle.   Then just put that faded circle on a black screen, and then put that completed screen over your display.

This shouldn't take a lot of time of process.  At it's heart, it's nothing more than a CLS and 2 _PUTIMAGE commands at work, after the initial first call.

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(Note that you can simply change the variable "WIDE" in the sub, if you want to change the size of the lightsource.  )