Validation program / regress test for GDK?

[Tor Lillqvist <tml iki fi>]

Hi,

With more and more backends for GDK appearing, has anybody written a
validation program? Such a program would do various GDK graphics
operations and compare the results, pixel by pixel, to those produced
by the X11 backend. (The X11 results would be generated and saved by
running the same program on X11, with some --generate switch).

Things that requires interaction from the user is probably harder to
validate automatically. The program could have an --interactive mode,
where the user would be asked to press various keys with various
modifier combinations, move the pointer in certain ways, etc. Or is
best test for interactive stuff that GTk+ widgets works as expected?

I ask because I am 98% sure that there are various fencepost
(off-by-one) errors in the Win32 backend. (For instance, the black
one-pixel shadow at the bottom/right edge of scroll bar sliders isn't
drawn when the slider is shrunk, until a redraw of the slider is
forced by moving the pointer over it so that it highlights.)

Partly these errors are due to the fact that the X11 and Win32
pixel-level semantics of various graphics concepts are different. I
have tried to take these differences into consideration, but probably
missed a few spots, or just made mistakes. Also, Win32's semantics are
not at all fully specified, like X11's are. I don't even know if there
is any other "official" specification than the SDK docs (which all
compiler vendors copy) that are of very varying quality. GDI docs in
particular seem to partly be the same as on Win 3.x...

Unless somebody else has such a program, I probably will write it
myself.

--tml