Groups > comp.sys.apple2.programmer > #2316

Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules"

Newsgroups	comp.sys.apple2.programmer
Date	2016-02-20 08:10 -0800
References	<2b4d01aa-0679-404d-93a3-1813bc37e7ee@googlegroups.com> <1aa59295-b514-4d91-babf-3fb788e6cd15@googlegroups.com> <a299dfc7-573c-4da1-822b-c8180a314cf6@googlegroups.com> <6c28aabe-cd46-48cf-8644-946d34215ebd@googlegroups.com>
Message-ID	<12e54a16-4fc9-4f5e-90a2-d0f833b6792c@googlegroups.com> (permalink)
Subject	Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules"
From	Mark Lemmert <mark.lemmert@gmail.com>

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> This is getting interesting. I tried poking the values 0x00 - 0x0F into the the first 16 screen locations going down the left hand side of the screen in AppleWin, and there were some surprising (to me) results.
> 
> Here is the resulting table:
> 
> B=black, W=white, V=violet, G=green
> 

Great observations!

There many posters to this thread who know much more than I do about "why" things work the way they do (getting into hardware, frequencies etc). My respect to all of them for their knowledge and appreciation for sharing it. 


That said, I've accumulated some "general rules" that are fairly accurate for making sense of the various quirks, which I've used successfully to write complex graphics, including 4 frame animation, game "tile-based" graphics etc. I'm also still not sure what double byte mode is, so everything that follows is coming from the perspective of single byte mode (if that is the correct term). 

In case it helps, here are two that seems to relate to your observations: 


>3400:05  0-1-0-1  V-V-V-B  ****  V-B-V-B 
>2880:0A  1-0-1-0  B-G-G-G  ****  B-G-B-G 

The results you expected to the right of the asterisk are a 100% correct application of the rules in every graphics book I've read. 

The results to the left of the asterisks are exactly what I've expect to see based on the "undocumented" behavior I've seen in practice. 

In general, I've found that if two consecutive color columns have their pixels turned on, with the column between them left empty, the display result will be a three pixel color line. 

i.e. the pixel in that middle column is displayed as though it's turned on in binary and using the color of the adjacent pixels. If the pixel in the middle column on (111) would of course result in a 3 pixel white line.

This very reliable, and it's the primary principle I follow to draw horizontal solid color lines.


>2C80:0B  1-0-1-1  W-W-G-G  ****  W-W-B-G 
>3080:0C  1-1-0-0  B-B-W-W 
>3480:0D  1-1-0-1  V-V-W-W  ****  V-B-W-W 


This is also a very specific bit pattern that I've found to be useful as a general rule. Are you know, two or more adjacent horizontal pixels turned on result in white. 

If a color pixel is turned on with only one empty column between it and the white pixels, the empty column will be displayed as though it were turned on, using the same color as the as the color pixel that is turned on.

I've found this to be fairly reliable, but have occasionally hit some exceptions when the graphics get complicated. But if you were to do a test with this pattern, in my experience you would see it regardless of where on the screen you did it.

Thread

Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-15 11:40 -0800
  Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-15 12:33 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-15 12:38 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-15 14:11 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" dempson@actrix.gen.nz (David Empson) - 2016-02-16 14:22 +1300
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-15 18:33 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-15 14:08 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-15 19:39 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-15 19:47 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" David Schmidt <schmidtd@my-deja.com> - 2016-02-15 23:25 -0500
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-16 08:42 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-16 11:28 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-18 14:53 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-18 15:28 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 15:31 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-18 15:42 -0800
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 15:52 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 16:09 -0800
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 16:42 -0800
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-22 11:01 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" dempson@actrix.gen.nz (David Empson) - 2016-02-19 12:47 +1300
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 15:49 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 16:02 -0800
  Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-16 11:34 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-16 12:00 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-16 13:47 -0800
  Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-16 13:41 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-16 19:02 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-17 18:09 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" marc.depeo@brbent.com - 2016-02-18 00:43 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-18 01:48 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" AppleIIGSMarc <appleiigsmarc@gmail.com> - 2016-02-18 08:50 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" AppleIIGSMarc <appleiigsmarc@gmail.com> - 2016-02-18 10:45 -0800
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-18 20:24 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-18 20:32 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" AppleIIGSMarc <appleiigsmarc@gmail.com> - 2016-02-18 21:05 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-18 15:08 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-18 15:31 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-18 13:18 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-18 18:15 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-03-01 11:58 -0800
  Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-16 14:05 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-16 19:12 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" "Michael J. Mahon" <mjmahon@aol.com> - 2016-02-17 15:22 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-17 16:14 -0800
  Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-19 14:34 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-19 16:17 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-19 19:19 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-19 22:25 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-19 23:12 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-19 23:27 -0800
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-19 23:31 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-20 04:02 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-20 11:40 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-20 11:48 -0800
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-20 08:10 -0800
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-20 16:25 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-20 16:37 -0800
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-20 18:29 -0800
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-20 20:00 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-02-20 20:53 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-20 23:11 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-21 00:23 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-21 01:41 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-21 01:43 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-21 02:29 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-21 02:40 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" wssimms@gmail.com - 2016-02-21 08:03 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-21 09:55 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-21 10:28 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-02-21 14:42 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael J. Mahon <mjmahon@aol.com> - 2016-02-22 14:13 -0600
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-02-21 20:49 -0800
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" anthonypaulo@gmail.com - 2017-06-22 17:19 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2017-06-22 18:05 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" awanderin <awanderin@gmail.com> - 2017-06-22 23:00 -0600
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael J. Mahon <mjmahon@aol.com> - 2017-06-23 12:59 -0500
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" David Schmenk <dschmenk@gmail.com> - 2017-06-23 13:12 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2017-06-25 07:30 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" anthonypaulo@gmail.com - 2017-06-25 08:30 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael J. Mahon <mjmahon@aol.com> - 2017-06-25 13:55 -0500
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Charlie <charlieDOTd@verEYEzon.net> - 2017-06-23 11:26 -0400
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2017-06-25 07:45 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" anthonypaulo@gmail.com - 2017-06-25 08:33 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" anthonypaulo@gmail.com - 2017-06-25 08:38 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" David Schmenk <dschmenk@gmail.com> - 2017-06-25 12:07 -0700
                Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" anthonypaulo@gmail.com - 2017-06-25 16:29 -0700
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael J. Mahon <mjmahon@aol.com> - 2016-02-20 00:27 -0600
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" denisbytezone@gmail.com - 2016-02-19 23:14 -0800
  Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-03-01 11:48 -0800
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael J. Mahon <mjmahon@aol.com> - 2016-03-01 16:24 -0600
    Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Mark Lemmert <mark.lemmert@gmail.com> - 2016-03-02 10:05 -0800
      Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Finger <mike.finger@gmail.com> - 2016-04-06 13:21 -0700
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-04-06 13:32 -0700
        Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2016-04-06 15:15 -0700
          Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2017-06-25 06:17 -0700
            Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" gids.rs@sasktel.net - 2017-06-25 21:33 -0700
              Re: Assembly Hi-Res Graphics, question about color patterns that seem to violate the "rules" Michael Pohoreski <michael.pohoreski@gmail.com> - 2017-06-26 11:12 -0700

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