[FreeWRL-develop] Testing > linux > .rgb -> .bmp

[doug s. <hig...@ho...>]

>> .
>> gm compare -metric mse fixture/1_wrl.0001.png playback/1_wrl.0001.png
>> (shows a statistical table with 0.00000 difference)
>> gm compare fixture/1_wrl.0001.png playback/1_wrl.0001.png -file diff.png -highlight-color purple -highlight-style Assign
>> # win32: gm convert diff.bmp win:
>> # linux: gm display diff.png
>> gm display diff.png
>> (shows a .png snapshot image with any different pixels highlighted in purple - no differences)
>> .
> .
> in win32 I got a gm compare difference when I did
> freewrl 1.wrl -R -F
> freewrl 1.wrl -P
> to generate the fixture while recording. I got a few pixels different.
> .
> When I did it in 3 steps:
> freewrl 1.wrl -R
> freewrl 1.wrl -F
> freewrl 1.wrl -P
> Then the fixture and playback images are identical.
> .
> Hypotheses:
> H0: it has something to do with the cursor, which is over the window during -R
> H1: random - need to do more tests to see if it happens again
>
.
On linux, for -F --fixture and -P --playback testing modes only, I changed Snapshot.c to save to windows .bmp format which has a 58 byte header, and stores uncompressed -instead of .rgb which has no header, or .png which by default gets some compression. GraphicsMagick on linux will display it:
gm display 1_wrl.0001.bmp
There's no date stamp or filename stored in the .bmp header, so 2 test fixtures should not differ in the header, so perl compare should work as well as gm compare. And any differences won't be due to compression since there isn't any.
-Doug