模拟放烟火的程序
从地面放到空中，爆炸后消失
FB源码（VFB源码，在勇芳编程群里下载）
Const Pi = 4 * Atn(1) Dim Shared As Double TwoPi = 8 * Atn(1) Dim Shared As Double RtoD = 180 / Pi ' radians * RtoD = degrees Dim Shared As Double DtoR = Pi / 180 ' degrees * DtoR = radians ScreenRes 640,480,32 Type SPARK As Single px 'position As Single py As Single vx 'velocity As Single vy As ULong c 'color As Integer a 'radius of explosion As Integer exploding End Type Const N=100 Dim Shared As SPARK sparks(0 To N-1) Dim Shared As Integer total Sub drawSparks() Dim As Single dx,dy,angle,rr ScreenLock Cls If total<>0 Then For i As Integer = 0 To total-1: If i < total-N Then i=total-N With sparks(i Mod N) If .py < 240 Then .exploding = 1 'random sparks within circle radius rr For j As Integer = 0 To 29 rr = Int(Rnd(1)*.a) 'gets wider each time angle = Int(Rnd(1)*360)*DtoR dx = Cos(angle)*rr dy = Sin(angle)*rr Circle(.px+dx,.py+dy),Int(Rnd(1)*2)+1,.c,,,,f Next j .px = .px + .vx .py = .py + .vy .vy = .vy + 0.1 'gravity If .exploding = 1 Then .a = .a + 1 'increase width End If End With Next i End If ScreenUnlock End Sub Dim As ULong r,g,b Dim As Integer f 'red,green or blue sparks Do If Int(Rnd(1)*50)=0 Then With sparks(total Mod N) .a = 2 .px = 320 .py = 430 .vx = Int(Rnd(1)*5)-2 .vy = -8 .exploding = 0 r = Int(Rnd(1)*255) g = Int(Rnd(1)*255) b = Int(Rnd(1)*255) 'choose a bright color f = Int(Rnd(1)*3) If f = 0 Then r = 255 If f = 1 Then g = 255 If f = 2 Then b = 255 .c = RGB(r,g,b) End With total += 1 End If drawSparks() Sleep 5 Loop Until Len(Inkey) Const P
