On 3/13/02 at 10:06 PM Marcel Kilgus wrote:

> Now that you mention stippling, it is my opinion that when having
> 16 bit colours there is no need for stipples anymore (I mention this
> because I've heard that Tony invested quite a lot of thinking about
> how to get stipples in). What is the general opinion about that?

My opinion would be that it would be nice to have a thing that could
calculate a 16BPP (or 15BPP) stipple of sorts out of a 24BPP definition so
applications can use this but I don't think it really needs to be
implemented as part of the PE (not to mention that it seems to be very
difficult). I can hardly see a need for a user interface to use more than
32/64k colors.

>>> Hmm, on the one hand there's already the normal palette mode which is
>>> well defined and I think it's unlikely that the user changes it.

>> Which one would that be? i hope we are not talking about the 256 color
>> system palette imposed by the PC? Or am i missing something?

>No, I mean the palette SMSQ uses on palette calls. It's predefined
>with certain colours (list is at the end of GD2 docs) and I think that
>most people will leave it this way.

Ah... I see.

>> IMHO this might prove to be a serious problem in the future given
>> the philosophy of WMAN - simply because the save areas increase
>> 8-fold, the consequence of which is the speed of their manipulation
>> decreases by the same factor.

> I know...
> Most manipulations aren't really much slower than their 2bit
> equivalent, the calculations are a lot simpler. The problem comes when
> big chunks of memory need to be altered

That's precisely what I meant. Scrolling must be the biggest issue, but in
an environment with background update, this is an issue one cannot really
solve (just thinking in advance here).

> Finally in the end there should be a standard graphics library thing
> which can be consulted for all things involving graphics manipulation,
> like colour conversions so that not every single application has to
> implement that stuff etc. And those routines could be accelerated,
> too.

All I can say is: AMEN!

>> It really undermines one of it's best qualities: speed/simplicity.
>> Just don't get me wrong, I don't think this is something that needs
>> immediate attention...

> Well, I really hope that people make their applications more
> colourful. I do encourage to brush up older applications

Agreed - the question being, HOW colorful do they need to be? Certainly not
4 colors. 16 would already be more like it, 256 is already pushing it a
bit. Mind you, the idea is to have whatever number of colors chosen from a
15BPP palette, so essentially, they get more colorfull eve if they only use
4 colors.

> e.g. Jochen is currently trying to get the QPAC2 source code so that
> we/I can extend it. This is very important in my eyes).

Agreed.

> But I need to know how much save area to allocate beforehand. What
> happens if an application is considered 2bit only and all of a sudden
> it issues an iow.papt (true colour paper trap) call with some exotic
> colour?

The result would be the use of the aforementioned thing that does color
conversion, and the result of that would be a 2-bit stipple definition. See
below.

>> What I meant is that hardware capable of doing >4 colors can still show
>> the 4 colors and given proper screen drivers, 'lesser mode' applications
>> will still work without modification, just like they do now with the new
>> drivers.

> I'm not completely sure whether I get this right, you're proposing
> some sort of the old MODE4-MODE8 switch? Well, for one I don't like
> that and hardware like the Qx0 do make a problem there because the 4
> colour mode is restricted to the poor 512x256 resolution.

No, the 'mode switch' would really only establish what kind of save area te
job needs and change the way a color definition as given is interpreted by
the driver - It would be a 'property' linked with the main application
window. There would also be a 'system variable' where the default for this
would be set if the job does not provide a value.
The idea is precisely not to have the jobs know they are running in a
particular mode unless they ask for it speciffically. This is a big plus
because even with your extensions to the PE, you will hardly tend to use a
large number of colors. If you define the system default to be 16 colors,
and use a real screen at 16BPP, programs that don't specify a mode will use
16 colors - if so desired out of a palette of whatever number of colors the
actual hardware provides. The color conversion routines take care that when
a job specifies a color, you get something close to it on the screen. If
your actual screen is not set for many colors or it simply can't do it, you
gat a stipple. The idea is to remove the need for programs to cater for
multiple screen modes which certainly does not help things right now. The
system palette is a huge help with this.
Now, don't get me wrong, I fully understand that this is a VERY tall order.
And it's not something to do _right_now_ but something to think about for
the future. At this point, you only make recomendations :-)

>> Apps writen for mode 4 work in 32/33 simply because the drivers
>> translate for them.

> I wouldn't call it "translate". The applications issue a "I want a red
> paper" call and the screen driver handles this in a way suitable for
> the graphics mode. There isn't really any 2bpp->16bpp translation
> involved.

Well, that's exactly what I meant - the driver handles it, whatever it is.
The application doesn't need to know - and that's a GOOD thing!!!

>> Francois Lanciault wrote: 
>> Could you please, PLEASE add GD2 support to the Aurora ? It would
>> add a lot of users to High Color migration. I know it is probably
>> not easy but I'm sure Nasta will help !!

> Well, I am considering it. But I also expect this to be many many
> many hours of work. I don't even have the hardware for it.

Someone mentioned that the QXL drivers have a 256 color mode? If so, that
could be used as a template.
It would certainly be a very welcome developement!

Nasta

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