Pr0100-getting started with processing  (Page 3/3)

When you do, a window should appear that looks something like Image 2 where the two animated rectangles move from left to rightacross the screen.

Figure

Output from the cars sketch.

Run in JavaScript mode

Although it isn't easy to see, there is a button in the upper-right corner of the PDE in Image 1 that allows you to select an output mode. (The default output mode is Java.) Assuming that your default browser supports the canvas element in HTML 5, selecting the JavaScript output mode and clicking the run button will cause the sketch output to appear inyour browser as shown in Image 3 . (See the complication involving images.)

Figure

Image 3. javascript output mode.

A folder named web-export

That will also cause a folder named web-export to be created in your Processing sketchbook folder. The web-export folder will contain a file named index.html . Opening that file in your HTML 5 compatible browser will produce the output shown in Image 3 , which is the same output that you should see by clicking here .

A caution regarding JavaScript mode

Not all sketches that can be written in Processing can be successfully run in JavaScript mode. For example, there are two tabs on the references page:

• Standard Processing
• JavaScript (Processing.js)

If you examine the contents of those two tabs, you will see that some of the items that appear on the Standard Processing tab are "grayed out" on theJavaScript tab. If you plan to run your sketch in JavaScript mode, you should probably restrict yourself to using only the items on the JavaScript tab.

In addition, the Processing.js Quick Start - Processing Developer Edition page explains a number of restrictions that apply to the JavaScript mode.

Export and run as an application

Finally, selecting Export Application on the File menu, checking the Windows box, and clicking the Export button will cause two additional folders to be created in your sketchbook folder. (Checking Mac OS X or Linux will cause different folders to be created.)

• application.windows32
• application.windows64

Those folders contain everything you need to run your sketch as a stand-alone application on the selected platform.

Dealing with image and sound files

Although the sketch in this module doesn't involve image files, sketches in future modules will involve image files and possibly sound files as well.

The PDE expects image files and sound files to be located in a folder named data that is a child of the folder containing the files with the .pde extension. You should make certain that they are located there.

However, (and this is unusual), when writing the Java code, you need to write it as though the image file is in the same folder as the pde file. Inother words, when referring to the file as a string, don't include the path to the data folder.

Summary

In this module, I showed you how to create an animated Processing sketch that can be run in any of three ways:

• Run directly from the PDE.
• Run in JavaScript mode.
• Export and run as an application.

Click here to see a live demonstration of the sketch in your HTML 5 compatible browser.

What's next?

In the next module, I will dissect and explain the structural anatomy of the Processing framework.

Miscellaneous

This section contains a variety of miscellaneous information.

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