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Groups > comp.sys.apple2.programmer > #2226 > unrolled thread

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

Started byMark Lemmert <mark.lemmert@gmail.com>
First post2016-02-15 11:40 -0800
Last post2017-06-26 11:12 -0700
Articles 20 on this page of 98 — 16 participants

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  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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#2408

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-03-01 11:58 -0800
Message-ID<0f6ad8a8-b147-4f25-95e1-0cdf353830cf@googlegroups.com>
In reply to#2261
On Thursday, February 18, 2016 at 1:48:05 AM UTC-8, wss...@gmail.com wrote:
> Comparisons with standard Applewin aren't very helpful as it has poor emulation of the NTSC display. Here is NTSC Applewin, although unfortunately the "blue guys" aren't present in the screen shot.
> 
> http://wsxyz.net/images/u5ct.png

Unfortunately that is not accurate for a few reasons :-/

1. On the Apple Color Composite monitor, colors are not "solid". If you're talking about *other* Composite monitors, then OK. :-)

2. While I _love_ the 50% scanline option, due to the low DPI, that doesn't match exactly match the shadow mask. I estimate every other scanline needs to be 50% smaller to better emulate the "gaps" in the shadow mask.

3. I'm NOT seeing a yellow bleed, but a GREEN bleed on both of my monitors (Apple Color Composite Monitor and Franklin Composite Monitor.)  Can anyone else try this on real hardware and post if they see:

i) yellow bleeding, or
ii) green bleeding

where the green forest hits the right white inside border?

4. That green looks anemic. :-(  I've mentioned AppleWin's NTSC color palette needs some TLC before.

Close though!

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#2246

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-16 14:05 -0800
Message-ID<73d10537-7de8-461a-a619-00ff732d700e@googlegroups.com>
In reply to#2226
On Monday, February 15, 2016 at 11:40:12 AM UTC-8, Mark Lemmert wrote:
> Half bit shift, as I understand it, wouldn't explain this. I don't think Ultima V uses double hi-res as the only colors I've ever seen on screen are the single hi-res colors. I'm stumped! 

Yeah, U5 only uses (single) HGR since it runs on a 64K Apple ][.

http://i.ebayimg.com/images/g/eQ8AAOSwUuFWu2zD/s-l1600.jpg

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#2253

FromMark Lemmert <mark.lemmert@gmail.com>
Date2016-02-16 19:12 -0800
Message-ID<c76480d0-a856-42a8-a08c-c4399cba881d@googlegroups.com>
In reply to#2246
On Tuesday, February 16, 2016 at 4:05:11 PM UTC-6, Michael Pohoreski wrote:
> On Monday, February 15, 2016 at 11:40:12 AM UTC-8, Mark Lemmert wrote:
> > Half bit shift, as I understand it, wouldn't explain this. I don't think Ultima V uses double hi-res as the only colors I've ever seen on screen are the single hi-res colors. I'm stumped! 
> 
> Yeah, U5 only uses (single) HGR since it runs on a 64K Apple ][.
> 
> http://i.ebayimg.com/images/g/eQ8AAOSwUuFWu2zD/s-l1600.jpg


I started second guessing myself this evening. The observations in my OP were from the introduction screen. Tonight I "journeyed onward" to start the game itself and tracked down one of the Shadowlords and he was displayed different than in the introduction, specifically the odd/even color rules were followed and and empty column appeared between any vertical blue lines or pixels.

There is also a slight yellow tint on some of the letters on the intro screen when the game boots up that I didn't notice before. I see this on my physical Apple IIe as well as AppleWIN. 

This made me start wondering if maybe they did the introduction in double hi-res (not that it should matter for the vertical blue lines since double hi-res as I understand it is only "double" for black & white)

But, you make a very good point in your post with the Ultima V system requirements. If it runs on 64k, so no double hi-res. 

My physical Apple IIe is hooked up to a modern LCD TV so maybe that somehow causes the yellow tint, not sure. 

Anyway, sharing this additional info in case it sparks any other ideas. 

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#2257

From"Michael J. Mahon" <mjmahon@aol.com>
Date2016-02-17 15:22 -0800
Message-ID<x-udnahiqvEKnVjLnZ2dnUU7-X-dnZ2d@giganews.com>
In reply to#2253
On 2/16/2016 7:12 PM, Mark Lemmert wrote:
> On Tuesday, February 16, 2016 at 4:05:11 PM UTC-6, Michael Pohoreski wrote:
>> On Monday, February 15, 2016 at 11:40:12 AM UTC-8, Mark Lemmert wrote:
>>> Half bit shift, as I understand it, wouldn't explain this. I don't think Ultima V uses double hi-res as the only colors I've ever seen on screen are the single hi-res colors. I'm stumped!
>>
>> Yeah, U5 only uses (single) HGR since it runs on a 64K Apple ][.
>>
>> http://i.ebayimg.com/images/g/eQ8AAOSwUuFWu2zD/s-l1600.jpg
>
>
> I started second guessing myself this evening. The observations in my OP were from the introduction screen. Tonight I "journeyed onward" to start the game itself and tracked down one of the Shadowlords and he was displayed different than in the introduction, specifically the odd/even color rules were followed and and empty column appeared between any vertical blue lines or pixels.
>
> There is also a slight yellow tint on some of the letters on the intro screen when the game boots up that I didn't notice before. I see this on my physical Apple IIe as well as AppleWIN.
>
> This made me start wondering if maybe they did the introduction in double hi-res (not that it should matter for the vertical blue lines since double hi-res as I understand it is only "double" for black & white)
>
> But, you make a very good point in your post with the Ultima V system requirements. If it runs on 64k, so no double hi-res.
>
> My physical Apple IIe is hooked up to a modern LCD TV so maybe that somehow causes the yellow tint, not sure.
>
> Anyway, sharing this additional info in case it sparks any other ideas.
>

The yellow tint you see is one of the more subtle NTSC color artifacts. 
  Since almost all Apple II color displays were on NTSC color TVs, most 
game graphic designers had this in mind as they created their graphics. 
  The yellow tint could be intentional or not, but it was certainly seen 
and approved by the designers.

The gap between blue "dots" in a horizontal line is a result of 
excessively high chroma bandwidth.  NTSC chroma bandwidth was on the 
order of 1MHz, so adjacent blue dots (actually two video dot times for 
each HGR "color" pixel) did not resolve the two dots fully, instead 
blending them.  The same is true for all solid color areas.

The gap between two successive horizontal lines (visible in a vertical 
line) is the result of the Apple video raster being non-interlaced, 
meaning that there are less than half as many horizontal lines as in a 
standard NTSC raster.  If the CRT has a well-focused electron beam, then 
this will result in vertical lines being "dotted" rather than "solid". 
Most small color TVs used with Apple II's did not focus so well that 
these dots were obtrusive, though later, larger TVs did show the 
discontinuous nature of adjacent horizontal scan lines.

Most VGA display adapters for the Apple II "double" each scan line, so
that the space between adjacent Apple lines is less obtrusive.
-- 

-michael

NadaNet 3.1 for Apple II parallel computing!
Home page:  http://michaeljmahon.com

"The wastebasket is our most important design
tool--and it's seriously underused."

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#2258

FromMark Lemmert <mark.lemmert@gmail.com>
Date2016-02-17 16:14 -0800
Message-ID<099d398f-cdae-4ed5-ae1c-22f7d5069081@googlegroups.com>
In reply to#2257
> The yellow tint you see is one of the more subtle NTSC color artifacts. 
>   Since almost all Apple II color displays were on NTSC color TVs, most 
> game graphic designers had this in mind as they created their graphics. 
>   The yellow tint could be intentional or not, but it was certainly seen 
> and approved by the designers.
> 
> The gap between blue "dots" in a horizontal line is a result of 
> excessively high chroma bandwidth.  NTSC chroma bandwidth was on the 
> order of 1MHz, so adjacent blue dots (actually two video dot times for 
> each HGR "color" pixel) did not resolve the two dots fully, instead 
> blending them.  The same is true for all solid color areas.
> 
> The gap between two successive horizontal lines (visible in a vertical 
> line) is the result of the Apple video raster being non-interlaced, 
> meaning that there are less than half as many horizontal lines as in a 
> standard NTSC raster.  If the CRT has a well-focused electron beam, then 
> this will result in vertical lines being "dotted" rather than "solid". 
> Most small color TVs used with Apple II's did not focus so well that 
> these dots were obtrusive, though later, larger TVs did show the 
> discontinuous nature of adjacent horizontal scan lines.


Michael,

Thanks very much for your reply!

That is great to know the source of the yellow. 

Sounds like you know the functionality of the underlying hardware very well.

In the OP I described a situation where I found two vertical blue lines in directly adjacent columns. Does that sound like something the hardware should be capable of? 



For example:

(where b = the pixels of the blue line, L = line, B = screen byte). This seems to violate the rules as byte 1 is an odd numbered byte/column. 

-------------------------- 
    B0 B1 B2 B3 B4 B5 B6 
L0     b 
L1     b 
L2     b 
L3         b 
L4         b 
L5         b 
L6         b 

*extract of single hi-res screen [!40 bytes (columns) x !192 lines] 
-------------------------- 


That is supposed to be impossible under the programming rules taught in the graphics book; I've read many and they've all said that blue can only be used on even columns.

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#2294

Fromdenisbytezone@gmail.com
Date2016-02-19 14:34 -0800
Message-ID<1aa59295-b514-4d91-babf-3fb788e6cd15@googlegroups.com>
In reply to#2226
I've been trying to get the double byte method to work, and it mostly does work, but in some instances the resulting images look a bit off. So I was wondering if someone with a physical apple and a colour screen could try an experiment for me.

In the following description I have the bits ordered from most significant to least significant, which means the colour bit is on the left, and the pixels are interpreted in right-to-left order.

A byte with the value 0x06 converts to 0-0-0-0 0-1-1-0 in binary, which in my understanding means first pixel (column 0) equals 0 (black), the second pixel (column 1) equals 1 (green), the third pixel (column 2) equals 1 (violet) and the fourth pixel (column 3) equals 0 (black). However the two consecutive 1 bits (according to the apple manual) override the colours and become two consecutive white pixels.

So what actually appears on a physical apple? A green pixel followed by a violet pixel, or two white pixels? Because according to the double-byte method it should be two coloured pixels as they come from separate double-bytes.

For reference, I am using the Apple ][ Reference Manual 1979, pp 19. Please don't make me type in the entire section :)

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#2297

FromMark Lemmert <mark.lemmert@gmail.com>
Date2016-02-19 16:17 -0800
Message-ID<a299dfc7-573c-4da1-822b-c8180a314cf6@googlegroups.com>
In reply to#2294
On Friday, February 19, 2016 at 4:34:15 PM UTC-6, denisb...@gmail.com wrote:
> I've been trying to get the double byte method to work, and it mostly does work, but in some instances the resulting images look a bit off. So I was wondering if someone with a physical apple and a colour screen could try an experiment for me.
> 
> In the following description I have the bits ordered from most significant to least significant, which means the colour bit is on the left, and the pixels are interpreted in right-to-left order.
> 
> A byte with the value 0x06 converts to 0-0-0-0 0-1-1-0 in binary, which in my understanding means first pixel (column 0) equals 0 (black), the second pixel (column 1) equals 1 (green), the third pixel (column 2) equals 1 (violet) and the fourth pixel (column 3) equals 0 (black). However the two consecutive 1 bits (according to the apple manual) override the colours and become two consecutive white pixels.
> 
> So what actually appears on a physical apple? A green pixel followed by a violet pixel, or two white pixels? Because according to the double-byte method it should be two coloured pixels as they come from separate double-bytes.
> 
> For reference, I am using the Apple ][ Reference Manual 1979, pp 19. Please don't make me type in the entire section :)



I tried it on my physical Apple IIe and the result was two white pixels. Here is a screen shot. If you need any other physical Apple tests done, I'm happy to help with them. 


https://www.dropbox.com/s/sqw0m4zlx9tky9x/IMG_9307.JPG?dl=0

Heres is exactly what I did:

] HGR
] CALL -151
] 2000:06



I'm not familiar with the double byte method, so is there something else I would have needed to do to activate it? I checked the Apple ][ Reference manual pp 19 but didn't see anything about double bytes mentioned. It has a white cover with the Woz signature on the front. Maybe I've got the wrong one? 


> A byte with the value 0x06 converts to 0-0-0-0 0-1-1-0 in binary, which in my understanding means first pixel (column 0) equals 0 (black), the second pixel (column 1) equals 1 (green), the third pixel (column 2) equals 1 (violet) and the fourth pixel (column 3) equals 0 (black). However the two consecutive 1 bits (according to the apple manual) override the colours and become two consecutive white pixels.


In my experience this is 100% correct, under the single byte method.

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#2303

Fromdenisbytezone@gmail.com
Date2016-02-19 19:19 -0800
Message-ID<6c28aabe-cd46-48cf-8644-946d34215ebd@googlegroups.com>
In reply to#2297
> 
> In my experience this is 100% correct, under the single byte method.

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

2000:00  0-0-0-0  B-B-B-B
2400:01  0-0-0-1  V-B-B-B
2800:02  0-0-1-0  B-G-B-B
2C00:03  0-0-1-1  W-W-B-B
3000:04  0-1-0-0  B-B-V-B
3400:05  0-1-0-1  V-V-V-B  ****  V-B-V-B
3800:06  0-1-1-0  B-W-W-B
3C00:07  0-1-1-1  W-W-W-B
2080:08  1-0-0-0  B-B-B-G
2480:09  1-0-0-1  V-B-B-G
2880:0A  1-0-1-0  B-G-G-G  ****  B-G-B-G
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
3880:0E  1-1-1-0  B-W-W-W
3C80:0F  1-1-1-1  W-W-W-W

I have a photo of the results, but I think I have transcribed them correctly. The results that surprised me are marked above with asterisks, followed by what I expected to see.

If someone could write a program to poke these values into the correct memory locations I would be very grateful. In fact why stop at 16, can we do the whole 256 spread over several columns? My assembler skills aren't really up to scratch for that.

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#2304

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-19 22:25 -0800
Message-ID<c40af636-4ecd-4d83-ab77-a83679b17d4a@googlegroups.com>
In reply to#2303
On Friday, February 19, 2016 at 7:19:55 PM UTC-8, denisb...@gmail.com wrote:
> > 
> If someone could write a program to poke these values into the correct memory locations I would be very grateful. In fact why stop at 16, can we do the whole 256 spread over several columns? My assembler skills aren't really up to scratch for that.

You mean something like this?

https://cloud.githubusercontent.com/assets/7876796/5530575/58664c54-89d6-11e4-95f0-6886b770b7e2.JPG

You can use Applesoft to generate that:

1 HGR:HCOLOR=0:B=0:GOTO 5
2 HPLOT X*14,Y*2+D:A=PEEK(38)+256*PEEK(39):P=A+X*2
3 POKE P,B*(1-D):POKE P+1,0: POKE P+9,B*(1-D):POKE P+10,0: POKE A+18,127:POKE A+20,255: POKE A+23,127:POKE A+25,255
4 RETURN
5 FOR X=0 TO 3:FOR Y=0 TO 63
6 D=0:GOSUB 2
7 D=1:GOSUB 2
8 B=B+1:NEXT:NEXT:B=0
9 FOR I=0 TO 7:HCOLOR=I:HPLOT 0,132+I*2 TO 28,132+I*2:NEXT

It is saved as "MAKE.256" on my NTSC.dsk
http://michael.peopleofhonoronly.com/dev/applewin/ntsc/ntsc.dsk

You may find this thread interesting ...
https://github.com/AppleWin/AppleWin/issues/254

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#2307

Fromdenisbytezone@gmail.com
Date2016-02-19 23:12 -0800
Message-ID<dff053db-635c-4b3f-b4bd-fbee76b87523@googlegroups.com>
In reply to#2304
On Saturday, 20 February 2016 17:25:49 UTC+11, Michael Pohoreski  wrote:
> On Friday, February 19, 2016 at 7:19:55 PM UTC-8, denisb...@gmail.com wrote:
> > > 
> > If someone could write a program to poke these values into the correct memory locations I would be very grateful. In fact why stop at 16, can we do the whole 256 spread over several columns? My assembler skills aren't really up to scratch for that.
> 
> You mean something like this?
> 
> https://cloud.githubusercontent.com/assets/7876796/5530575/58664c54-89d6-11e4-95f0-6886b770b7e2.JPG
> 
> You can use Applesoft to generate that:
> 
> 1 HGR:HCOLOR=0:B=0:GOTO 5
> 2 HPLOT X*14,Y*2+D:A=PEEK(38)+256*PEEK(39):P=A+X*2
> 3 POKE P,B*(1-D):POKE P+1,0: POKE P+9,B*(1-D):POKE P+10,0: POKE A+18,127:POKE A+20,255: POKE A+23,127:POKE A+25,255
> 4 RETURN
> 5 FOR X=0 TO 3:FOR Y=0 TO 63
> 6 D=0:GOSUB 2
> 7 D=1:GOSUB 2
> 8 B=B+1:NEXT:NEXT:B=0
> 9 FOR I=0 TO 7:HCOLOR=I:HPLOT 0,132+I*2 TO 28,132+I*2:NEXT
> 
> It is saved as "MAKE.256" on my NTSC.dsk
> http://michael.peopleofhonoronly.com/dev/applewin/ntsc/ntsc.dsk
> 
> You may find this thread interesting ...
> https://github.com/AppleWin/AppleWin/issues/254

Excellent! Good to know I'm only several years behind on this.

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#2309

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-19 23:27 -0800
Message-ID<8e1522f5-219d-4f3f-a489-db344dd32201@googlegroups.com>
In reply to#2307
On Friday, February 19, 2016 at 11:12:08 PM UTC-8, denisb...@gmail.com wrote:
> > > If someone could write a program to poke these values into the correct memory locations I would be very grateful. In fact why stop at 16, can we do the whole 256 spread over several columns? My assembler skills aren't really up to scratch for that.

That's how you learn -- by doing.

You can just use the mini-assembler -- once you keep track of the variables

        GBASL   = $26   ; HGR pointer to cursor
        GBASH   = $27
        HPOSN   = $F411 ; A=row, X=col.lo,Y=col.hi, sets GBASL, GBASH
        HGR     = $F3E2

        high    = $FA
        byte    = $FB
        col     = $FC
        row     = $FD
        saveX   = $FE
        saveY   = $FF

Copy & Paste ...

- - - 8< - - -
CALL-151
!
300: JSR $F3E2
 LDY #0
 STY $FB
 STY $FC
 STY $FA
 STY $FD
 TYA
 LDX $FC
 LDY #0
 JSR $F411
 LDA $FB
 LDY $FC
 INY
 STA ($26),Y
 INY
 LDA $FA
 STA ($26),Y
 INC $FB
 LDY $FD
 INY
 INY
 STY $FD
 CPY #$80
 BNE $30D
 LDY #0
 LDX $FC
 INX
 INX
 INX
 INX
 STX $FC
 TXA
 AND #$F
 BNE $30B
 LDA $FA
 EOR #$80
 BEQ $348
 STA $FA
 LDY #0
 BEQ $30B
 RTS

300G
- - - 8< - - -

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#2310

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-19 23:31 -0800
Message-ID<0dada6de-faef-40c1-bcff-d8cf6cc37b45@googlegroups.com>
In reply to#2309
Here's the actual assembly source that I used to generate the alt. source for the mini-assembler.
I'm pulling a Sheldon with no comments. :-)

        GBASL   = $26   ; HGR pointer to cursor
        GBASH   = $27
        HPOSN   = $F411 ; A=row, X=col.lo,Y=col.hi, sets GBASL, GBASH
        HGR     = $F3E2

        high    = $FA
        byte    = $FB
        col     = $FC
        row     = $FD
        saveX   = $FE
        saveY   = $FF

        JSR HGR
        LDY #0
        STY byte
        STY col
        STY high
@NextCol
        STY row
@NextRow
        TYA
        LDX col
        LDY #0
        JSR HPOSN

        LDA byte
        LDY col
        INY
        STA (GBASL),Y
        INY
        LDA high
        STA (GBASL),Y
        INC byte

        LDY row
        INY
        INY
        STY row
        CPY #$80
        BNE @NextRow

        LDY #0
        LDX col
        INX
        INX
        INX
        INX
        STX col
        TXA
        AND #$F
        BNE @NextCol

        LDA high
        EOR #$80
        BEQ @Done
        STA high

        LDY #0
        BEQ @NextCol
@Done
        RTS

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#2314

Fromwssimms@gmail.com
Date2016-02-20 04:02 -0800
Message-ID<48c76c26-1eab-4227-ba0c-b8093dc7703a@googlegroups.com>
In reply to#2310
Am Samstag, 20. Februar 2016 16:31:51 UTC+9 schrieb Michael Pohoreski:
> Here's the actual assembly source that I used to generate the alt. source for the mini-assembler.
> I'm pulling a Sheldon with no comments. :-)
> 
>         GBASL   = $26   ; HGR pointer to cursor
>         GBASH   = $27
>         HPOSN   = $F411 ; A=row, X=col.lo,Y=col.hi, sets GBASL, GBASH
>         HGR     = $F3E2

If only you'd made it all lowercase, and gotten rid of these useless equates, it would be perfect.

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#2322

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-20 11:40 -0800
Message-ID<f91f7217-0f4b-427a-b040-40fbfad658c7@googlegroups.com>
In reply to#2314
On Saturday, February 20, 2016 at 4:02:07 AM UTC-8, wss...@gmail.com wrote:
> Am Samstag, 20. Februar 2016 16:31:51 UTC+9 schrieb Michael Pohoreski:
> > Here's the actual assembly source that I used to generate the alt. source for the mini-assembler.
> > I'm pulling a Sheldon with no comments. :-)
> > 
> >         GBASL   = $26   ; HGR pointer to cursor
> >         GBASH   = $27
> >         HPOSN   = $F411 ; A=row, X=col.lo,Y=col.hi, sets GBASL, GBASH
> >         HGR     = $F3E2
> 
> If only you'd made it all lowercase, and gotten rid of these useless equates, it would be perfect.

There's always a comedian in every crowd. :-)

Yup, that contains some left over crap that I should have deleted.
i.e. GBASLH, saveX, saveY, etc.

I've tried lowercase assembly on a few occasions.  Just not my cup of tea due to SNR; I find it easy to "tune" out the uppercase so I can focus on the lowercase vars.  If everything was lowercase it is much harder to read only the variables. i.e. everything becomes "noise".  Hell most of the time I ignore the opcode mnemonics since it is so easy with uppercase.

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#2323

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-20 11:48 -0800
Message-ID<ae76fc39-d25a-4de2-8d16-542251d44beb@googlegroups.com>
In reply to#2314
On Saturday, February 20, 2016 at 4:02:07 AM UTC-8, wss...@gmail.com wrote:
> If only you'd made it all lowercase, and gotten rid of these useless equates, it would be perfect.

/snarky What, too lazy to select all & press **two** keys in Vim: U~ ? :-)

        gbasl   = $26   ; hgr pointer to cursor
        hposn   = $f411 ; a=row, x=col.lo,y=col.hi, sets gbasl, gbash
        hgr     = $f3e2

        high    = $fa
        byte    = $fb
        col     = $fc
        row     = $fd

        jsr hgr
        ldy #0
        sty byte
        sty col
        sty high
@nextcol
        sty row
@nextrow
        tya
        ldx col
        ldy #0
        jsr hposn

        lda byte
        ldy col
        iny
        sta (gbasl),y
        iny
        lda high
        sta (gbasl),y
        inc byte

        ldy row
        iny
        iny
        sty row
        cpy #$80
        bne @nextrow

        ldy #0
        ldx col
        inx
        inx
        inx
        inx
        stx col
        txa
        and #$f
        bne @nextcol

        lda high
        eor #$80
        beq @done
        sta high

        ldy #0
        beq @nextcol
@done
        rts


 

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#2316

FromMark Lemmert <mark.lemmert@gmail.com>
Date2016-02-20 08:10 -0800
Message-ID<12e54a16-4fc9-4f5e-90a2-d0f833b6792c@googlegroups.com>
In reply to#2303
> 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. 

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#2324

Fromdenisbytezone@gmail.com
Date2016-02-20 16:25 -0800
Message-ID<61b2d263-ab64-49a6-bd27-2e336cbf8772@googlegroups.com>
In reply to#2316
> 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.

Thanks for the information, I didn't realise it was going to be this weird.

I have updated my DiskBrowser to handle these new 'rules', there is now a 'Colour Quirks' menu option so that you can toggle between the two display methods (using alt-Q). It's on GitHub now and should be available through homebrew fairly soon.

I have an example of two screens posted here - https://www.dropbox.com/sh/tumzba618qh4hij/AACMDmLcMEO-TWgBJXcTNPEea?dl=0 It uses Michael's excellent ntsc.dsk.

Are there any more of these quirks that I should know about? mjm suggested earlier that 10-12 surrounding pixels can affect any pixel.

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#2325

FromMichael Pohoreski <michael.pohoreski@gmail.com>
Date2016-02-20 16:37 -0800
Message-ID<46603f99-fde0-4080-bb51-31ef115f641e@googlegroups.com>
In reply to#2324
On Saturday, February 20, 2016 at 4:25:11 PM UTC-8, denisb...@gmail.com wrote:
> Are there any more of these quirks that I should know about? mjm suggested earlier that 10-12 surrounding pixels can affect any pixel.

Technically the Apple //e can display 12-bit color = 4,096 colors.

You'll probably be interested in this project that I ripped out of our sister project "AppleWin NTSC"
https://github.com/Michaelangel007/hgr2rgbntsc

I need to make another pass since I'm not happy with the accuracy of the colors, but it should be good enough to get started.

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#2326

FromMark Lemmert <mark.lemmert@gmail.com>
Date2016-02-20 18:29 -0800
Message-ID<a7204633-4abd-4357-94a2-026bd3a4c113@googlegroups.com>
In reply to#2324
>Thanks for the information, I didn't realise it was going to be this weird. 

Welcome to the twilight zone of Apple II hi-res graphics :-)

The good news is, while it does take a little getting used to, it's not that bad once you do.


>Are there any more of these quirks that I should know about? 

Another one is regarding adjacent vertical color lines. For example:


-------------------------- 
    C0 C1 C2 C3 C4 C5 C6 C7
L0  b 
L1  b 
L2  b 
L3           b 
L4           b 
L5           b 
L6           b 

(b = the pixels of a blue line, L = line, C = column or bit)
(extract of single hi-res screen, upper left corner)

Note that some of the earlier posts used a diagram which used the terminology color pixel. In the above example C0 & C2 would be color pixel #0, using that terminology. 

the binary for line 1 and two would be:
10000001
10000100


As noted in prior posts, C7 and and the 1st column/bit in the next byte would together form a color pixel.

The above example has two adjacent vertical color lines. By this I mean there are two color vertical color lines that are as close together as two lines of the same color can be drawn, with only one empty column between them (column 0 and column 2 in this case, with column 1 being the empty column)

This type of bit pattern varies greatly in how it is rendered on in various emulators and displays. Here is a summary of what I've observed and compiled on this topic:


1) Virtual II Emulator (mac OS X) displays blue, and probably other colors, double wide, which makes the lines appear flush with no empty column between them. 

2) AppleWIN 1.25.03 displays blue only in even columns as expected from the "rules" in the graphics books. 


3) My physical Apple IIe's display (a modern flatscreen TV), connects blue lines with a smudged, slightly dimmer diagonal line. Sometimes. 

I haven't fully quantified this yet, but I'm pretty sure it's location dependent. There are some posts earlier in this thread about what's going on at the hardware/frequency level. 

4) I've heard reports that CRT TVs connected to physical Apple IIs display an empty column between the vertical blue lines but it's not as noticeable as it is on AppleWIN due to a little haze around the pixels. Lots of earlier posts about the hardware/frequency reasons for this.

Blue is used as an example but I'm pretty sure it applies to adjacent vertical lines of any color (I haven't tested them all, but have found no exceptions so far).   


Conclusion:

The way I manage this quirkiness with the visual difference in vertical color lines on different emulators and displays, is to program to the lowest common denominator. 

IMO the least visually appealing rendering above the above displays is AppleWIN (no offense intended to it's creators, I think it's a great program overall, very accessible to many users). So, when I test my graphics the first thing I do is make sure they look acceptable in AppleWIN. Periodically I test in other emulators and on my physical IIe, but generally I've found if it looks acceptable in AppleWIN it will look acceptable or better in the other environments mentioned above. 

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#2327

Fromgids.rs@sasktel.net
Date2016-02-20 20:00 -0800
Message-ID<88903293-8ad9-4031-9094-795fa8474f51@googlegroups.com>
In reply to#2326
On Saturday, February 20, 2016 at 8:29:45 PM UTC-6, Mark Lemmert wrote:
> >Thanks for the information, I didn't realise it was going to be this weird. 
> 
> Welcome to the twilight zone of Apple II hi-res graphics :-)
> 
> The good news is, while it does take a little getting used to, it's not that bad once you do.
> 
> 
> >Are there any more of these quirks that I should know about? 
> 
> Another one is regarding adjacent vertical color lines. For example:
> 
> 
> -------------------------- 
>     C0 C1 C2 C3 C4 C5 C6 C7
> L0  b 
> L1  b 
> L2  b 
> L3           b 
> L4           b 
> L5           b 
> L6           b 
> 
> (b = the pixels of a blue line, L = line, C = column or bit)
> (extract of single hi-res screen, upper left corner)
> 
> Note that some of the earlier posts used a diagram which used the terminology color pixel. In the above example C0 & C2 would be color pixel #0, using that terminology. 



This was not what was said at all in earlier posts.  Please go back and read them more carefully.  Your mis-understanding and mis-interpretation of the apple graphics screen is totally off the mark.  And please stop calling bits, columns.  This is very unprofessional in computer language.

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