Number: 339

Date: 28-Mar-84  9':44':52

Submitter: Sannella.PA

Source: Jellinek.pa

Subject: Want AREAFILL instruction added to DLion microcode

Lisp Version: 

Description: '
Date': 27 Mar 84 14':14 PST'
From': Jellinek.pa'
Subject': Lisp': Wanted':  DLion area-fill microcode'
To': LispSupport.pa'
cc': Jellinek.pa, Lichtenberg.wbst'
Lisp-System-Date': 27-Mar-84 08':53':34'
Machine-Type': Dolphin'
'
Larry Masinter suggested I make this suggestion "official"':   I''d love for there to be an AREAFILL instruction added to the DLion microcode repertoire, for doing filling of arbitrary polygons drawn on bitmaps.'
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I really don''t know enough about DLion microcode (yet) to spec this out in any great detail, but I would appreciate all comments and suggestions.'
'
		Herb'
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-----'
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From': lichtenberg.wbst'
Date': 28-Mar-84 23':07':46 EST'
Subject': Re': Lisp': Wanted':  DLion area-fill microcode'
In-reply-to': Jellinek.pa''s message of 27 Mar 84 14':14 PST'
To': Jellinek.pa'
cc': LispSupport.pa, Lichtenberg'
'
'
'
Fill algorithms can be pretty complex, depending on what you want to do...'
'
Do you want to be able to fill concave polygons or polygons that double over on themselves (like a gigure "8" or something?  That makes it harder.)  Or do you want to fill normal closed polygons?  What would you be using for a boundary on the polygon?  Do you want to fill the polygon with an arbitrary shade?'
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Are you sure you don''t want an opcode to generate a mask bitmap for use with BITBLT, that way you get the most features, and less microcode has to be written.  '
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All in all, sounds like a neat idea.  If it''s important, I''ll look into some algorithms and see if it is feasible and try to get an estimate on how much space/time/programmer time it takes.  OK?'
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/Mitch.'
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-----'
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Date': 29 Mar 84 09':29 PST'
From': Jellinek.pa'
Subject': Re': Lisp': Wanted':  DLion area-fill microcode'
In-reply-to': lichtenberg.wbst''s message of 28-Mar-84 23':07':46 EST'
To': lichtenberg.wbst'
cc': Jellinek.pa, LispSupport.pa'
'
Mitch,'
	Thanks for your message.  I''ll try to clarify.'
I''d like an opcode that would generate a mask bitmap for use with BITBLT.  As you point out, that would afford the most flexibility for (maybe) the least microcode.  As for the type of polygons to be filled':  normal closed polygons would be easiest, and seem to be the most common case.'
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		Herb'
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Date': 29 MAR 84 18':27 PST'
From': JONL.PA'
Subject': Re': Lisp': Wanted':  DLion area-fill microcode'
To':   Jellinek, LispSupport'
cc':   Lichtenberg.wbst, JONL, Burton'
'
In response to the message sent  27 Mar 84 14':14 PST from Jellinek.pa'
'
I''m not completely "up" on algorithms to do area filling, but I do know'
of an application in ZetaLisp which uses triangulation -- namely it fills an'
area under neath a curve by "coloring in" a lot of little triangles.'
'
Maybe Burton or LIchtenberg.wbst has some knowledge about this?'
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-----'
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Date': 29 Mar 84 18':40 PST'
From': Jellinek.pa'
Subject': Re': Lisp': Wanted':  DLion area-fill microcode'
In-reply-to': JONL.PA''s message of 29 MAR 84 18':27 PST'
To': JONL.PA'
cc': Jellinek.PA, LispSupport.PA, Lichtenberg.wbst, Burton.PA'
'
Hmm.  Sounds like an interesting technique; I wonder if will work for the general case of filling an arbitrary closed polygon?'
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I''m familiar with two other techniques':  1) the standard, dumb 4-way recursive fill, and 2) parity fill.'
Check out Theo Pavlidis, "Algorithms for Graphics and Image Processing," p. 171 for more info.'
'
	Herb'
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Workaround: 

Test Case: 

Edit-By: Sannella.PA

Edit-Date: 30-Mar-84 16':04':37

Attn: Charnley.pa

Assigned To: 

In/By: 

Disposition: 

System: Language Support

Subsystem: Microcode

Machine: 

Disk: 

Microcode Version: 

Memory Size: 

File Server: 

Server Software Version: 

Difficulty: 

Frequency: Intermittent

Impact: Moderate

Priority: Unlikely

Status: Wish

Problem Type: Performance

Source Files: