Balls rain from the top, some bouce then sink away.

[Dav]

I'm sure making this kind of thing is a piece of cake to a lot of you, but it was a learning experience for me.  Had a little help on it.

Balls rain from the top, some bounce with gravity, then sink away.

- Dav

Code: (Select All)

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

'BALLRAIN.BAS

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

'Balls rain from the top, some drop, some bounce then sink away.

'For QB64 by Dav, SEP/2023



SCREEN _NEWIMAGE(1000, 600, 32)



balls = 200 'number of balls on screen, 200 is my laptop's comfort zone



DIM ballx(balls), bally(balls), ballxvel(balls), ballyvel(balls), ballsize(balls)

DIM ballred(balls), ballgrn(balls), ballblu(balls)



'make random ball values

FOR b = 1 TO balls

    ballx(b) = RND * (_WIDTH) 'x position

    bally(b) = RND * -(_HEIGHT) 'y position

    ballxvel(b) = INT(RND * 7) 'x speed

    ballyvel(b) = INT(RND * 3) 'y speed

    ballsize(b) = RND * 15 + 10 'ball size

    ballred(b) = RND * 255 'red color

    ballgrn(b) = RND * 255 'green color

    ballblu(b) = RND * 255 'blue color

NEXT



DO

    CLS



    FOR b = 1 TO balls



        IF bally(b) < _HEIGHT - ballsize(b) THEN



            ballx(b) = ballx(b) + ballxvel(b)

            bally(b) = bally(b) + ballyvel(b)



            IF ballx(b) < ballsize(b) OR ballx(b) > _WIDTH - ballsize(b) THEN

                ballxvel(b) = -ballxvel(b)

            END IF



            IF bally(b) < ballsize(b) OR bally(b) > _HEIGHT - (ballsize(b) * 2) THEN

                ballyvel(b) = -ballyvel(b)

            END IF



            ballyvel(b) = ballyvel(b) + 3 'gravity value

            'ballxvel(b) = ballxvel(b) + (Rnd * 1.2 - Rnd * 1.2) 'x shake



            'draw gradient ball

            FOR y2 = bally(b) - ballsize(b) TO bally(b) + ballsize(b)

                FOR x2 = ballx(b) - ballsize(b) TO ballx(b) + ballsize(b)

                    clr = (ballsize(b) - (SQR((x2 - ballx(b)) * (x2 - ballx(b)) + (y2 - bally(b)) * (y2 - bally(b))))) / ballsize(b)

                    IF clr > 0 THEN PSET (x2, y2), _RGB(clr * ballred(b), clr * ballgrn(b), clr * ballblu(b))

                NEXT

            NEXT



        END IF

    NEXT



    'see if balls done

    onscreen = 0

    FOR b = 1 TO balls

        IF bally(b) < _HEIGHT - ballsize(b) THEN onscreen = 1

    NEXT

    IF onscreen = 0 THEN EXIT DO



    _DISPLAY

    _LIMIT 24



LOOP