Written in February 2003
Edited in May 12th 2005
This package contains two classes. The main properties of a chart are defined in the main class.
The name of the main class is 'chart.class.php'.
This class has enough comments for the necessary parts so everyone can understand the different parts.
This class also has a calculate() method that calculates data fractions.
The properties for this class are as follows:
1-elements: The type of this property is 'array' and contains input values.
2-elementnames: The type of this property is also 'array' and contains input value names.
3-colors: The type of this property is also 'array' and contains the data for colors that are going to be used in drawing the chart.
These color names are stored in an array named 'colornames'. This array can be updated very easily.
All you need to do is adding new color names and their "RGB" values.
The second class inherits its characteristics from the main class and is its child.
Its name is 'piechart.class.php'. This class has a constructor that initializes the class with the input values.
The class has three methods: createimage(),draw() and out($filename,$quality).
1-createimage(): This method is used to create an image and is used as an internal method in the other two methods.
2-draw(): This method draws the chart and sends the result to the browser.
3-out($filename,$quality): This method generates a "JPG" picture and writes it to the disk.
It needs the folder to have write permission for everyone. This method needs two parameters.
The first parameter is the name of the file you want the picture to be saved as and the next parameter is the picture quality.
A number between 0 and 100. 0 is the poorest and 100 is the best quality.
Some new features are added to the class. Now you can have links for each part of the pie chart. You can also have an HTML output. Two fuctions were added to piechart.class.php. The first one is setLink() which prints the <MAP> information of the chart. The second function is GenerateHtmlCode() which as it sounds generates html code. This function is necessary to use when you piechart with link suppirt. Two new variables were also added to the class. $Coords and $links, The first variable is used to calculate the points to be used in <area> part of the <MAP> tag. The second one is used to store links for each part of the chart.
A new sample file (piechart2.php) is added to show how to use a piechart with support for links.
I should apologize for my bad English and I hope you forgive me for that because I am not a native speaker.