[interfacekit] Re: Provisional BBitmap, libstorage.so Integration

["Jeremy Rand" <jrand@xxxxxxxx>]

I should have mentioned some of the issues I found with SetBits() and 
B_GRAY1.  I reported this to Be quite some time ago, I think the bug 
report was 980426-142100.  I think they acknowledged it but nothing 
more.  Perhaps if you have a copy of the Be bug archive, you can look 
it up.  The bug report will probably not tell anyone anything we don't 
already know.

Speaking of which, has anyone perused the bug database for app kit and 
interface related issues?  Perhaps an understanding of what issues 
there are with a class before we get too deep into implementing it 
would be helpful.

>Hi folks,
>
>I finished my implementation of a provisional BBitmap and incorporated 
>libstorage.so into libopenbeos.so. So far everything still seems to 
>work (or in some cases still doesn't ;-).
>
>Regarding BBitmap, I realized, that BBitmap::SetBits() does not only 
>have a weird specification, but the R5 implementation is also pretty 
>much broken. For those who aren't familar with it: SetBits() imports 
>data from a supplied buffer into the bitmap's data, doing color space 
>conversion, if necessary. Unfortunately the guy spec'ing this methods 
>must have considered it to be a good idea, that when specifying 
B_RGB32 
>as the color space for the supplied data, actually B_RGB24_BIG 
>formatted data without row padding are expected. Whereas for other 
>color spaces the respectively formatted (+padded) data are required. 
>Even more unfortunate is the fact, that the function doesn't implement 
>this behavior very closely, e.g. if B_CMAP8 is given, padding must be 
>omitted, but only if the bitmap itself doesn't use B_CMAP8, otherwise 
>it is needed. Support for B_GRAY1 seems to be completely broken.
>
>To deal with these problems I implemented two new, more powerful 
>methods, namely BBitmap::ImportBits(), which work as expected, and 
>mapped SetBits() to them, mimicing the original behavior as closely as 
>reasonable. I would tend to declare SetBits() deprecated, as it is 
>quite some source of confusion. E.g. the original implementors of 
>BNodeInfo and BAppFileInfo didn't seem to know, that SetBits() behaves 
>as it does, for they use it to convert bitmaps from and to B_CMAP8 
(for 
>icons), which doesn't work, for the reasons mentioned above. BTW, I 
was 
>ignorant myself and used SetBits() when implementing these classes, 
but 
>I will fix that tomorrow. I guess the icon methods of BMimeType need 
to 
>be reviewed as well.
>
>Well, it looks like we're drawing near milestone 2. Only some bits of 
>BMimeType functionality are missing and the BRoster::FindApp() 
>methods...
>
>CU, Ingo
>
>
>
--
Jeremy Rand
jrand@xxxxxxxx

Other related posts:

[interfacekit] Provisional BBitmap, libstorage.so Integration

[interfacekit] Re: Provisional BBitmap, libstorage.so Integration

[interfacekit] Re: Provisional BBitmap, libstorage.so Integration