Re: [AL] TrueColor and Palette (part III)

[Shawn H. <sh...@ta...>]

George Foot <geo...@me...> writes:
>Don't call Allegro functions before initialising Allegro, and
>don't load any images for use in high colour depth modes until
>you've set the graphics mode unless you really know what
>you're doing.

That is of course very good advice. But you've made me think, this is a
very common problem. Is there any way that we can prevent people from
making this mistake? Unfortunately I can't just bomb out from any text
mode bitmap load calls with an error message, because there are some
situations where that is actually valid (eg. in the dat utility). But
almost always, it is an error.

Perhaps any bitmap load call without first either setting a graphics
mode or calling set_color_conversion() should generate an assert
failure?

Another thing that occurred to me is that it might be a good idea to
initialise the default truecolor pixel format to BGR, rather than the
current RGB. Rationale: this would still work correctly for programs
like dat that do all manipulations in text mode, but would create an
obvious visual error if programs get the loading and mode setting in the
wrong order, because the display would be RGB while their data was BGR.
At the moment that kind of code contains a subtle error because it will
fail only on rare hardware, but if I changed this, it would go wrong
obviously on most machines, so people would be forced to find and fix
the problem.

Is that worthwhile, or is it to cruel for me to break all the programs
that currently "sort of" work?


--
Shawn Hargreaves - sh...@ta... - http://www.talula.demon.co.uk/
"A binary is barely software: it's more like hardware on a floppy disk."
>From <all...@ma...> Tue Mar 30 16:02:23 1999
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From: "Stefan Schimanski" <1S...@gm...>
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Subject: Re: [AL] WinAllegro: Is there a way to do accellerated masked blits without crashing?
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> 
> Hi.  Is there a way to use DirectX's color-key functions on a surface
> attached to an allegro bitmap without it crashing?
> 
> If so, how about an example code for it?

No, this is not possible in the current WIP.
--
      o Stefan Schimanski
  ( )   1S...@gm...
o       http://1Stein.home.pages.de