Space Orbs. Small screen saver.

[Dav]

Here's a little screen saver showing pulsating orbs over a starry background with plasma clouds.  I was playing around some old code, turned it into something new. Tested and runs OK under Windows and Linux.

- Dav 

Code: (Select All)

'=============

'SpaceOrbs.bas

'=============

'Screensaver of Orbs pulsating in space

'Coded by Dav for QB64-PE, AUGUST/2023



RANDOMIZE TIMER



SCREEN _NEWIMAGE(1000, 640, 32)





'=== orb settings



orbs = 60 'number of orbs on screen

OrbSizeMin = 5 'smallest size an orb can get

OrbSizeMax = 60 'largest size an orb can get



DIM OrbX(orbs), OrbY(orbs), OrbSize(orbs), OrbGrowth(orbs)





'=== generate some random orb values



FOR i = 1 TO orbs

    OrbX(i) = RND * _WIDTH 'x pos

    OrbY(i) = RND * _HEIGHT 'y pos

    OrbSize(i) = OrbSizeMin + (RND * (OrbSizeMax - OrbSizeMin)) 'orb size

    OrbGrowth(i) = INT(RND * 2) 'way orb is changing, 0=shrinking, 1=growing

NEXT





'=== make a space background image



FOR i = 1 TO 100000

    PSET (RND * _WIDTH, RND * _HEIGHT), _RGBA(0, 0, RND * 255, RND * 225)

NEXT

FOR i = 1 TO 1000

    x = RND * _WIDTH: y = RND * _HEIGHT

    LINE (x, y)-(x + RND * 3, y + RND * 3), _RGBA(192, 192, 255, RND * 100), BF

NEXT





'=== grab screen image for repeated use



back& = _COPYIMAGE(_DISPLAY)





DO



    '=== place starry background first



    _PUTIMAGE (0, 0), back&





    '=== draw moving plasma curtain next



    t = TIMER

    FOR x = 0 TO _WIDTH STEP 3

        FOR y = 0 TO _HEIGHT STEP 3

            b = SIN(x / (_WIDTH / 2) + t + y / (_HEIGHT / 2))

            b = b * (SIN(1.1 * t) * (_HEIGHT / 2) - y + (_HEIGHT / 2))

            LINE (x, y)-STEP(2, 2), _RGBA(b / 3, 0, b, RND * 25), BF

        NEXT: t = t + .085

    NEXT





    '=== now process all the orbs



    FOR i = 1 TO orbs



        '=== draw orb on screen



        FOR y2 = OrbY(i) - OrbSize(i) TO OrbY(i) + OrbSize(i) STEP 3

            FOR x2 = OrbX(i) - OrbSize(i) TO OrbX(i) + OrbSize(i) STEP 3

                'make gradient plasma color

                IF SQR((x2 - OrbX(i)) ^ 2 + (y2 - OrbY(i)) ^ 2) <= OrbSize(i) THEN

                    clr = (OrbSize(i) - (SQR((x2 - OrbX(i)) * (x2 - OrbX(i)) + (y2 - OrbY(i)) * (y2 - OrbY(i))))) / OrbSize(i)

                    r = SIN(6.005 * t) * OrbSize(i) - y2 + OrbSize(i) + 255

                    g = SIN(3.001 * t) * OrbSize(i) - x2 + OrbSize(i) + 255

                    b = SIN(2.001 * x2 / OrbSize(i) + t + y2 / OrbSize(i)) * r + 255

                    LINE (x2, y2)-STEP(2, 2), _RGBA(clr * r, clr * g, clr * b, 5 + RND * 15), BF

                END IF

            NEXT

        NEXT



        '=== change orb values



        'if orb is shrinking, subtract from size, else add to it

        IF OrbGrowth(i) = 0 THEN OrbSize(i) = OrbSize(i) - 1 ELSE OrbSize(i) = OrbSize(i) + 1

        'if orb reaches maximum size, switch growth value to 0 to start shrinking now

        IF OrbSize(i) >= OrbSizeMax THEN OrbGrowth(i) = 0

        'if orb reaches minimum size, switch growth value to 1 to start growing now

        IF OrbSize(i) <= OrbSizeMin THEN OrbGrowth(i) = 1

        'creates the shakiness. randomly adjust x/y positions by +/-3 each

        IF INT(RND * 2) = 0 THEN OrbX(i) = OrbX(i) + 3 ELSE OrbX(i) = OrbX(i) - 3

        IF INT(RND * 2) = 0 THEN OrbY(i) = OrbY(i) + 3 ELSE OrbY(i) = OrbY(i) - 3



    NEXT



    _DISPLAY



    _LIMIT 15



LOOP UNTIL INKEY$ <> ""