Re: Summary of drawing routines?
Re: Summary of drawing routines?
- Subject: Re: Summary of drawing routines?
- From: "David W. Halliday" <email@hidden>
- Date: Thu, 07 Jun 2001 16:10:21 -0500
- Organization: Latin AmeriCom, formerly Latino Online
John C. Randolph wrote:
>
On Thursday, June 7, 2001, at 08:31 AM, Clyde McQueen wrote:
>
>
> I keep looking in the online docs for a summary of all the methods used
>
> to draw (text, images, etc.). Am I missing something?
>
>
No, not really.
>
>
There are quite a few different ways to draw in Cocoa. Most of the
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things we used to do with Postscript path operations are now done with
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NSBezierPath. Bitmap images are drawn using NSImage and NSImageRep.
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Text is drawn using NSAttributedString, NSText, etc. 3d drawing is done
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with OpenGL, typically in an NSOpenGLView.
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>
Basically, there's no single place in the docs that deals with all the
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ways to get something to the screen or printer in Cocoa.
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>
-jcr
>
...
Basically, Clyde, the reason there is no single place that describes
drawing and/or printing things is because of the difference between the
procedural approach vs. the object oriented approach. In the Object Oriented
view of the way things work, every object that will have a visual
representation will know how to create that representation itself (it can
"draw" itself)---nothing else knows how to do this (we just give it a context
in which to "draw" itself and tell it to "go for it"---it handles the
details). (The same will be true if, for instance, there will be an audio
interface---the objects, themselves, will be responsible for expressing
themselves.)
Another feature of this is that the methods for doing this "drawing" will
be the same for all similar objects, whether or not they are common
subclasses---they will adhere to the same "protocol" (whether formal or
informal).
David email@hidden