DOCUMENT:Q153927  11-JAN-2001  [vbwin]
TITLE   :HOWTO: Create Pie Charts Using the Circle Method in VB
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:4.0
OPER/SYS:
KEYWORDS:kbgraphic kbprogramming kbVBp400

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The information in this article applies to:

 - Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Professional Edition, 16-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Enterprise Edition, 16-bit, for Windows, version 4.0 
 - Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0 
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SUMMARY
=======

The Pinnacle-BPS Graph control shipping with Visual Basic gives users the
ability to create pie charts. The Pinnacle-BPS is a relatively large control and
uses a large amount of disk space on distribution disks. Therefore, the custom
effects available are limited to the features of the control. The Circle method
in the VBA language provides functionality to draw arcs and segments. By drawing
segments, you can easily create a pie chart and add custom features as you
require. Below is a code sample demonstrating how to do this.

MORE INFORMATION
================

1. Start a new Visual Basic project. Form1 is created by default.

2. Place a Command button on the form.

3. Place a 200x200 pixel Picture box on the form.

4. Add the following code to the Form1 code window:

         Option Explicit

         Public Sub DrawPiePiece(lColor As Long, fStart As Double, fEnd As
         Double)
           Const PI As Double = 3.14159265359
           Const CircleEnd As Double = -2 * PI
           Dim dStart As Double
           Dim dEnd As Double
           Picture1.FillColor = lColor
           Picture1.FillStyle = 0
           dStart = fStart * (CircleEnd / 100)
           dEnd = fEnd * (CircleEnd / 100)
           Picture1.Circle (100, 100), 60, , dStart, dEnd
         End Sub

         Private Sub Command1_Click()
           Picture1.ScaleMode = vbPixels
           Call DrawPiePiece(QBColor(1), 0.001, 36)
           Call DrawPiePiece(QBColor(2), 36, 55)
           Call DrawPiePiece(QBColor(3), 55, 75)
           Call DrawPiePiece(QBColor(4), 75, 99.999)
         End Sub

5. Press the F5 key to run the project. You should see a pie chart being drawn
   with four sections mirroring the four times that the DrawPiece routine was
   called in the Command1_Click event.


REFERENCES
==========

For more information, please see the following articles in the Microsoft
Knowledge Base:

   Q83906 How to Draw an Ellipse with Circle Statement in VB

   Q73280 Overflow in VB Drawing Circle Segment w/ Radius of Zero

Instead of using the Circle method in the VBA language, you can also use the
Win16/Win32 API Call to achieve the same result.

Additional query words:

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Keywords          : kbgraphic kbprogramming kbVBp400 
Technology        : kbVBSearch kbAudDeveloper kbVB400Search kbVB400 kbVB16bitSearch
Version           : WINDOWS:4.0
Issue type        : kbhowto

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