Question

When I use Spy++, I notice that mouse entering a button triggers a series of WM_TIMER .

How is Windows doing this? Is it requesting that the OS notify it or call a function pointer after X milliseconds, or does the widget register its own timer proc?

The reason I want to know this is because I’m building a game gui api in C++ and want to incorporate this sort of mechanism.

Thanks

Answer 1

MS Windows’s GUI animation capability is very limited. You can say nothing if you had known real animation capable OS like Mac OS X.

Windows GUI is a composition of various child windows which has own event handler routine and drawing code. Very clumsy and performance inefficient of course, only provide easy access to ordinary developers.

In short, I want to say that MS Windows is the least recommendable reference for developing a game GUI framework. If I have a opportunity to develop new GUI framework, first thing I would devise is a mechanism to separate input event handling and graphic drawing for consolidated screen drawing, like game programs do.

Have a look at this:
http://www.rawmaterialsoftware.com/juce.php

_{(source: rawmaterialsoftware.com)}