Hi all,
Use this code to make mouse tail using some image.
You need to add an image control and a timer control to form.
Load some image to image control.
Image name : ImgBall
Index : 0 (important)
Under timercontrol use this code
- Private Sub Timer1_Timer()
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Animate
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End Sub
Add this code under form load event::::
- Private Sub Form_Load()
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Call MUSICSND
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Dim I As Integer
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For I = ImgBall.UBound + 1 To 7
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Load ImgBall(I)
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ImgBall(I).Visible = True
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ImgBall(I).Top = ImgBall(I - 1).Top + 11
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Next I
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ImgBall(0).Visible = False
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Call InitVal
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Call InitBall
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Timer1.Interval = 20
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Timer1.Enabled = True
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End Sub
Add this code under form mousemove event
- Private Sub Form_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
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MoveHandler CLng(X), CLng(Y)
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Animate
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End Sub
Now add a module and write this code in module :::::
- Option Explicit
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Public Type Vec2D
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X As Long
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Y As Long
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End Type
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Public Type AnimBall
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Vec As Vec2D
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dx As Double
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dy As Double
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Img As Image
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End Type
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Dim nBalls As Integer
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Dim Xpos, Ypos
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Dim DeltaT As Double
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Dim SegLen
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Dim SpringK
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Dim Mass
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Dim Gravity
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Dim Resistance
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Dim StopVel As Double
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Dim StopAcc As Double
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Dim DotSize As Long
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Dim Bounce As Double
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Dim bFollowM As Boolean
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Dim balls() As AnimBall
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Function InitVal()
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' Some of the variables are still unknown to me
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nBalls = 7 ' numbers of ball
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Xpos = Ypos = 0 ' evaluate position
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DeltaT = 0.01 '
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SegLen = 10# ' it seem like the distance between the
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' mouse pointer and the ball
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' it's quite intersting to change the value
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' and see the effect
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SpringK = 11 ' spring constant,
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' if large, the longer and higher the tail
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' will swing
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Mass = 1 'mass of the ball
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Gravity = 40 ' gravity coeff,
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' if large, the balls are more difficult
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' to move upward
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Resistance = 9 ' resistivity of the ball to move itself
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' from a location, the larger the more difficult to
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' move
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StopVel = 0.1
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StopAcc = 0.1
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DotSize = 11 ' the size of the ball in pixel
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Bounce = 0.95 ' bouncing coeff,
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bFollowM = True ' animation flag
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End Function
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' must only be called after load all imgBall
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Function InitBall()
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Dim I As Integer
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ReDim balls(nBalls)
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For I = 0 To nBalls
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balls(I) = BallSet(MAINPAGE.ImgBall(I))
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Next I
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For I = 0 To nBalls
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balls(I).Img.Left = balls(I).Vec.X
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balls(I).Img.Top = balls(1).Vec.Y
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Next I
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End Function
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' initialize a ball
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Function BallSet(Img As Image) As AnimBall
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BallSet.Vec.X = Xpos
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BallSet.Vec.Y = Ypos
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BallSet.dx = BallSet.dy = 0
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Set BallSet.Img = Img
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End Function
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' initialize a vector variable
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Function VecSet(X As Long, Y As Long) As Vec2D
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VecSet.X = X
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VecSet.Y = Y
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End Function
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' update position when mouse move
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Function MoveHandler(X As Long, Y As Long)
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Xpos = X
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Ypos = Y
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End Function
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' calculate the spring force of the balls chain
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Function SpringForce(I As Integer, J As Integer, ByRef spring As Vec2D)
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Dim tempdx, tempdy, tempLen, springF
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tempdx = balls(I).Vec.X - balls(J).Vec.X
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tempdy = balls(I).Vec.Y - balls(J).Vec.Y
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tempLen = Sqr(tempdx * tempdx + tempdy * tempdy)
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If (tempLen > SegLen) Then
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springF = SpringK * (tempLen - SegLen)
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spring.X = spring.X + (tempdx / tempLen) * springF
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spring.Y = spring.Y + (tempdy / tempLen) * springF
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End If
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End Function
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' main routine of this animated balls
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' call on mouse move or every 20ms
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Function Animate()
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Dim iH, iW
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Dim start As Integer
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Dim I As Integer
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Dim spring As Vec2D
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Dim resist As Vec2D
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Dim accel As Vec2D
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' enable the animation
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If (bFollowM) Then
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balls(0).Vec.X = Xpos
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balls(0).Vec.Y = Ypos
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start = 1
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End If
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For I = start To nBalls
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spring = VecSet(0, 0)
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If (I > 0) Then
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Call SpringForce(I - 1, I, spring)
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End If
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If (I < (nBalls - 1)) Then
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Call SpringForce(I + 1, I, spring)
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End If
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resist = VecSet(-balls(I).dx * Resistance, -balls(I).dy * Resistance)
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accel = VecSet((spring.X + resist.X) / Mass, _
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(spring.Y + resist.Y) / Mass + Gravity)
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balls(I).dx = balls(I).dx + DeltaT * accel.X
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balls(I).dy = balls(I).dy + DeltaT * accel.Y
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If (Abs(balls(I).dx) < StopVel And _
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Abs(balls(I).dy) < StopVel And _
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Abs(accel.X) < StopAcc And _
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Abs(accel.Y) < StopAcc) Then
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balls(I).dx = 0
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balls(I).dy = 0
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End If
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balls(I).Vec.X = balls(I).Vec.X + balls(I).dx
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balls(I).Vec.Y = balls(I).Vec.Y + balls(I).dy
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' checking for boundary conditions
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iW = MAINPAGE.ScaleWidth
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iH = MAINPAGE.ScaleHeight
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' check bottom
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If (balls(I).Vec.Y >= iH - DotSize - 1) Then
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If (balls(I).dy > 0) Then
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balls(I).dy = Bounce * (-balls(I).dy)
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End If
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balls(I).Vec.Y = iH - DotSize - 1
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End If
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' check right
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If (balls(I).Vec.X >= iW - DotSize) Then
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If (balls(I).dx > 0) Then
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balls(I).dx = Bounce * (-balls(I).dx)
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End If
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balls(I).Vec.X = iW - DotSize - 1
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End If
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' check left
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If (balls(I).Vec.X < 0) Then
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If (balls(I).dx < 0) Then
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balls(I).dx = Bounce * (-balls(I).dx)
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End If
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balls(I).Vec.X = 0
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End If
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' check top
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If (balls(I).Vec.Y < 0) Then
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If (balls(I).dy < 0) Then
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balls(I).dy = Bounce * (-balls(I).dy)
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End If
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balls(I).Vec.Y = 0
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End If
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balls(I).Img.Left = balls(I).Vec.X
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balls(I).Img.Top = balls(I).Vec.Y
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Next I
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End Function
Regards
>> ALI <<
