Chapter 35 -- Handle All Video Modes

Chapter 35

Microsoft Windows provides the user many display options through the Display Control Panel applet. The property sheet's Settings tab includes options for the number of colors, for video resolution, and for the size of the font used. Combined, these options give the user a wide variety of choices in how a program appears on the screen.

You need to make sure your program handles all video modes. After all, your users are going to be using various combinations of these settings, and they are not going to appreciate having to change video modes just to use your program. Given the number of display options available, however, this task is certainly easier said than done. For example, on my computer I have the following options:

• Colors 16 Color, 256 Color, High Color (16 bit), and True Color (32 bit)
• Screen area 640 × 480, 800 × 600, 1024 × 768, 1152 × 864, 1280 × 1024, and 1600 × 1200
• Font size Small Fonts, Large Fonts, and Other (which allows a custom font size)

Not counting the Other font size category, these options provide for a total of 48 different video modes. Of course, it is simply not practical to develop and test all video combinations unless you plan on selling a whole lot of software. Instead, I recommend the following more realistic goals:

• Choose a minimum recommended video mode for your program.
• Make sure that your program fully supports that video mode or better.
• Provide "graceful degradation" so that your program is at least functional in modes less than the minimum recommended mode.

In the remainder of this chapter, I'll explore these goals and the steps necessary to achieve them.