Re: [Alephmodular-devel] Drawing Contexts - CDContext

[Br'fin <br...@ma...>]

On Monday, July 28, 2003, at 10:14  PM, Alexander Strange wrote:

>
> On Monday, July 28, 2003, at 06:24  PM, Br'fin wrote:
>
>> Yes, I know it's old and crusty in here. But I never know quite what 
>> to do aside from occasionally making some headway on the Display 
>> Abstraction.
>>
>> The general business I see CDContext dealing with will mainly be 
>> drawing lines, text, and filling areas. As such it will provide the 
>> support/features needed and provided by screen_drawing.cpp. As well 
>> as other areas where direct drawing commands are done upon a buffer. 
>> (For instance, asking a buffer to be erased/filled to a color)
>
> It would be useful if it also supported basic transforms like scaling 
> (so we can read terminals comfortably at high screen resolutions, 
> although we may not want to scale the pictures); Quartz and OpenGL 
> will handle this for you in OSX.
>
>> But that is probably fairly rare to begin with. And in the future may 
>> allow us to shift to a Quartz based drawing scheme. (Heh, 
>> anti-aliased text and map lines?)
>
> I would definetely recommend starting out with Quartz/CoreGraphics 
> instead of a QuickDraw API.
>
Well, I need more of the drawing context stuff in place before I can 
supersede it with Quartz stuff I think. Given the current layout of the 
code, I don't think there's any problems with using Quickdraw APIs. 
They would just break things in the drawing abstraction that aren't 
currently used by the code.

I do like the concept of a CScaledBuffer though. Something where you 
set it up like:
	scaled_buffer= buffer.get_scaled_buffer(Rectangle(640, 480, 0, 0));

And intervening code around things like the associated drawing context 
manipulates graphic commands; transforms things like the font used and 
the actual pixel locations.

-Jeremy Parsons