Gammon Forum

VERSION 5.00
Begin VB.Form Fireworks 
   Caption         =   "Form1"
   ClientHeight    =   3150
   ClientLeft      =   60
   ClientTop       =   390
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3150
   ScaleWidth      =   4680
   StartUpPosition =   3  'Windows Default
   Begin VB.PictureBox Display 
      BackColor       =   &H00000000&
      Height          =   3135
      Left            =   0
      ScaleHeight     =   3075
      ScaleWidth      =   4635
      TabIndex        =   0
      Top             =   0
      Width           =   4695
   End
   Begin VB.PictureBox Buffer 
     BackColor       =   &H00000000&
     Height          =   3135
     Left            =   0
     ScaleHeight     =   3075
     ScaleWidth      =   4635
     TabIndex        =   1
     Top             =   0
     Visible         =   0   'False
     Width           =   4695
  End
End
Attribute VB_Name = "Fireworks"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False

Private Sub Form_Load()
  Dim Call_it As Object
  Dim Res As Boolean
  Dim Temp_Obj As Object
  Dim List As Collection
  Set List = New Collection
  Do
    If List.count > 0 Then
      Objs = List.count
      Do
        Res = List(Objs).Spark_Draw
        If Res = True Then
          List.Remove (Objs)
        End If
        Objs = Objs - 1
      Loop Until Objs = 0
      Fireworks.Display.Picture = Fireworks.Buffer.Image
      'Replace with something to fade the colors to black.
      Fireworks.Buffer.Cls
    End If
    If Rnd() < 0.1 Then
      Set Temp_Obj = New Spark
      Temp_Obj.XStart = Int(Rnd() * 200)
      Temp_Obj.YStart = Int(Rnd() * 100)
      Temp_Obj.Color = RGB(Int(256 * Rnd()), Int(256 * Rnd()), Int(256 * Rnd()))
      List.Add Temp_Obj
      Temp_Obj = ""
    End If
  Loop
  Call_it = ""
End Sub

VERSION 5.00
Begin VB.UserControl Spark 
   Appearance      =   0  'Flat
   BackColor       =   &H80000005&
   BackStyle       =   0  'Transparent
   ClientHeight    =   90
   ClientLeft      =   0
   ClientTop       =   0
   ClientWidth     =   90
   ScaleHeight     =   90
   ScaleWidth      =   90
End
Attribute VB_Name = "Spark"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = True
Attribute VB_PredeclaredId = False
Attribute VB_Exposed = False
Option Explicit
Dim Px(100) As Integer
Dim Py(100) As Integer
Dim Vx(100) As Single
Dim Vy(100) As Single
Public XStart As Integer
Public YStart As Integer
Public Color As String
Private Step As Integer

Private Sub UserControl_Initialize()
  Dim count As Integer
  Dim PI As Single
  Dim Vect As Single
  PI = 3.1415926
  For count = LBound(Px) To UBound(Px)
    Px(count) = XStart
    Py(count) = YStart
    Vect = 2 * PI * Rnd()
    Vx(100) = Int((Cos(Vect) * 20)) / 20000
    Vy(100) = Int((Sin(Vect) * 20)) / 20000
  Next
  Step = 0
End Sub

Public Function Spark_Draw()
  'Put code to calc and draw dots here.
  Dim count
  For count = LBound(Px) To UBound(Px)
    Px(count) = Px(count) + Vx(count)
    Py(count) = Py(count) + Vy(count)
    Fireworks.Buffer.PSet (Px(count), Py(count)), Color
    Vx(count) = Vx(count) * 0.999
    Vy(count) = Vy(count) + 0.00001
  Next
  Step = Step + 1
  If Step = 800 Then
    Spark_Draw = True
  Else
    Spark_Draw = False
  End If
End Function

1. Create some basic objects.
2. Start loop
  a. Check to see the number of sparks that are active.
    - Execute the Spark_Draw function for each object.
    - Delete any Sparks that have finished.
  b. Move the draw buffer to the visible picturebox.
  c. Generate a random number and if under .1 create a new
     spark object.
3. Loop