Page 569 - Beginning PHP 5.3

Chapter 17: Generating Images with PHP

Figure 17-22

Using Text in Images

Adding text to images with PHP enables you to annotate images or draw dynamic charts and graphs.
The quickest and easiest way to add text to an image is to use the imagestring() function, which lets
you draw a string of text on your image at the location you specify.

Adding Standard Text

It ’ s easy to draw on your image with imagestring() because the function can use the set of built - in
system fonts for your text. This means that you don ’ t have to worry about loading a specific font on
your server.
imagestring() takes six parameters:

❑ The image resource
❑ The font to use for the text. This is an integer value and ranges from 1 upward. Values between
1 and 5 are the built - in system fonts; any fonts you load subsequently are represented by
numbers starting from 6
❑ The x and y values of the position of the text. These represent the top - left corner of the rectangle
within which your text will appear
❑ The text string that you want to draw
❑ The color of the text

To load a font for the imagestring() function, use the imageloadfont() function. It loads a
bitmap font that is architecture dependent; this means the font needs to be generated on the same type of
system that you want to use it on. A far easier solution is to use TrueType fonts — which you get to in
just a bit.

imagestring() returns true if it successfully added the text to the image, or false if there
was an error.

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