I don't know how one can do that but to compare screenshots.

One thing you can do is do grabs of the application window rather than the screen. In windows terms, Alt-PrintScreen rather than Ctl-PrintScreen. The advantage is that you remove the absolute position of the window from the equation.

An alternative is to capture the api/parameter sequences as they are passed into the device driver by using a device driver that logs this information or by interjecting dummy that logs and does pass-thru to the real thing. As I said, this is only really useful for testing window managers/gui libraries themselves and not applications.

Here I can spot another trap:* The test machine has some "skins" enabled (depending on the Widget Toolkit)

You run your testing on a "standard machine".

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
The "good enough" maybe good enough for the now, and perfection maybe unobtainable, but that should not preclude us from striving for perfection, when time, circumstance or desire allow.

In reply to Re^3: testing GUIs by BrowserUk
in thread testing GUIs by spurperl

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