Re: [ft] Pitch Smaller Than Bitmap Width + Make Build Errors

[Mickey Gabel]

Werner LEMBERG wrote:
> > I did not realize that even when I ask (and usually get) 8bpp
> > anti-aliased bitmaps, it seems that FT2 can still occasionally give
> > me 1bpp bitmaps.  I guess this is an embedded bitmap? I just assumed
> > that FT2 would convert it to 8bpp because I said
> > FT_RENDER_MODE_NORMAL.
> >
> > I think either the docs are misleading or this is a bug.
>
> Basically, it's a bug.  Theoretically, I could fix this by making
> FT_Render_Glyph() call FT_Bitmap_Convert().  However, for backwards
> compatibility, I fear this might not be a good idea, but I'm unsure.
>
> Opinions, please.
>
>
>     Werner

My two cents (haven't been using FT2 long enough to have an actual dollar):

1) If one is writing a string rendering routine, previously they would 
have to support both 8bpp and 1bpp bitmaps. If suddenly FT2 stops giving 
1bpp bitmaps, then all that means is that the code path for 1bpp is not 
used anymore. The routine still works.
I bet many people like me already stumbled on this case, shrugged, and 
implemented the 1bpp code path, assuming this is correct behaviour.


2) Actively asking FT for 8bpp rendering, yet still EXPECTING 1bpp 
bitmap on purpose seems like a very strange to do. I mean, if I ask for 
8bpp, at the very least I should handle the case where I get what I 
asked for :)
From an API standpoint, it seems a good change unless someone is doing 
something rather strange.

3) The biggest issues seems to me that there is performance AND memory 
consideration, as the additional conversion would require more memory 
than before, and would take more time to render.

4) Maybe change the meaning of FT_RENDER_MODE_NORMAL?
It could mean: "FT2 gives you 8bpp when we render, and occasionally 1bpp 
embedded bitmaps". Then you could add a flag for 
FT_RENDER_MODE_FORCE_8BIT, for those people who really insist on 8bpp 
and don't want to write the 1bpp code path?
The problem with this idea is that it's kind of taking the default, easy 
option. Like, "we don't really change anything, so you get the old (bad) 
behaviour unless you manually turn on the magic damn-you-get-it-right 
flag."

Disclaimer: I am a new user of FT2, and I use it only for rendering, so 
obviously there are things I have not considered,

Mickey