+CharlieChaplin Posted December 7, 2008 Share Posted December 7, 2008 Well, this was a theme in the "Atari vs. Commodore" thread, but I think we should have it in a separate topic... So please post all your info about A8 artifacting here. I will start with a simple (incomplete!) list of A8 titles that use artifacting - maybe someone can help me to complete this list... ?!? NTSC artefacting programs on the A8: - AE by Broderbund *** - Choplifter by Broderbund (cart and disk; the cart by Atari uses 4-color Gr. 15) - David`s Midnight Magic by Broderbund (disk) *** - David`s Midnight Magic by Atari (cart.) - Drol by Broderbund (disk) *** - Head over Heels by Hitsquad/US-Gold - Lode Runner by Broderbund (disk) - Lode Runner by Atari (cart.) - Pinball Construction Set by ECA (and all pinballs created with it!) *** - (most) Sierra online Hi-Res Adventures, like The Dark Crystal and ... - Threshold by ??? - Ultima 1 ? by Origin (not sure if it uses artifacting, since I have never seen it) - Ultima 2 ? by Origin (not sure if it uses artifacting, since I have never seen it) - Ultima 3 by Origin - Ultima 4 by Origin *** there are also cracked + patched versions of these programs in 4-color gr. 15 mode available... PAL artefacting programs on the A8: - Artifacting Character Editor by Joel Goodwin (Page 6, issue 52, pages 18-21) - Runaround by Joel Goodwin (Page 6, issue 53 ?) greetings, Andreas Koch. Quote Link to comment Share on other sites More sharing options...
kenfused Posted December 7, 2008 Share Posted December 7, 2008 Mr. Do (Only for EXTRA and at bottom of screen though) I know there were some old Pool games also. --Ken Quote Link to comment Share on other sites More sharing options...
potatohead Posted December 7, 2008 Share Posted December 7, 2008 Ultima I and II do use artifacting. It's the standard red / green variety. I think in II, they also dipped into the odd pixel patterns on occasion. I'm hooking up my 400 to the new HDTV to see how that all plays out, just for grins. Quote Link to comment Share on other sites More sharing options...
+remowilliams Posted December 7, 2008 Share Posted December 7, 2008 Autoduel and Ogre by Origin. Also two of my all time favorite games. Quote Link to comment Share on other sites More sharing options...
+remowilliams Posted December 7, 2008 Share Posted December 7, 2008 I'm hooking up my 400 to the new HDTV to see how that all plays out, just for grins. A][ plasma HDTV artifacting. Quote Link to comment Share on other sites More sharing options...
ZylonBane Posted December 7, 2008 Share Posted December 7, 2008 Pretty much only Apple II ports used artifacting. Night Mission Pinball, A.E., Lunar Leeper, Crossfire (disk version), Fooblitzky, Translyvania, AutoDuel, Marauder, etc... Quote Link to comment Share on other sites More sharing options...
FastRobPlus Posted December 7, 2008 Share Posted December 7, 2008 Well,this was a theme in the "Atari vs. Commodore" thread, but I think we should have it in a separate topic... So please post all your info about A8 artifacting here. I will start with a simple (incomplete!) list of A8 titles that use artifacting - maybe someone can help me to complete this list... ?!? NTSC artefacting programs on the A8: - AE by Broderbund *** - Choplifter by Broderbund (cart and disk; the cart by Atari uses 4-color Gr. 15) - David`s Midnight Magic by Broderbund (disk) *** - David`s Midnight Magic by Atari (cart.) - Drol by Broderbund (disk) *** - Head over Heels by Hitsquad/US-Gold - Lode Runner by Broderbund (disk) - Lode Runner by Atari (cart.) - Pinball Construction Set by ECA (and all pinballs created with it!) *** - (most) Sierra online Hi-Res Adventures, like The Dark Crystal and ... - Threshold by ??? - Ultima 1 ? by Origin (not sure if it uses artifacting, since I have never seen it) - Ultima 2 ? by Origin (not sure if it uses artifacting, since I have never seen it) - Ultima 3 by Origin - Ultima 4 by Origin *** there are also cracked + patched versions of these programs in 4-color gr. 15 mode available... PAL artefacting programs on the A8: - Artifacting Character Editor by Joel Goodwin (Page 6, issue 52, pages 18-21) - Runaround by Joel Goodwin (Page 6, issue 53 ?) greetings, Andreas Koch. These are mainly Apple II ports. Didn't Apple use artifacting to obtain color/resolution? I wonder if the fact that these games are ports is why they behave this way. Quote Link to comment Share on other sites More sharing options...
potatohead Posted December 7, 2008 Share Posted December 7, 2008 (edited) That's an Apple ][? Well, it (the 400) works on the new set as well as it did on the CRT. All I've got is the crappy RF. I can't see the sub-pixels on the RF input. Not surprising there. I need to mod this 400. Newer TV's make a lot of RF noise. That was worth learning. Some of the other color patterns, such as 01011010110 didn't produce the colors I expected to see. That one should be a bright pink or yellow. Without composite, or better, there is no chance of seeing the high-res modes I described in the other threads. Is that a double high-res game by chance? I'm sure the ports are artifacting because the game logic could use a lot of the same positioning and graphics data. Edited December 7, 2008 by potatohead Quote Link to comment Share on other sites More sharing options...
Bryan Posted December 7, 2008 Share Posted December 7, 2008 I'm not clear on how the Apple ][ scheme worked. I know the color circuits worked by running the pixels though a delay that produced the same effect as artifacting on the A8, but I don't know if the programmer actually needed to draw those on-off patterns. Quote Link to comment Share on other sites More sharing options...
potatohead Posted December 7, 2008 Share Posted December 7, 2008 (edited) Working in assembly language meant drawing those patterns. The graphics screen is 40 bytes wide, 7 pixels per byte, with the most significant bit being the phase shift bit. (first real color cell, IMHO!) In APPLE BASIC, the user could just ask for colors, and the graphics would be drawn in that color. If there is a phase bit conflict, last draw wins! This can be easily seen by drawing a cyan rectangle, then plotting a blue line through it. The graphics routines would boil down the color and position request to the nearest artifacted pixel. Really, there were just pixels. Monochrome pixels. The color circuit would either slightly delay them or not, and the position of the pixel gave the color, and that's it for the Apple. 7 pixels per byte, and if you put two of them next to one another, on or off, they would be black or white. Plot them alone, and they would be one of 4 possible colors, depending on the state of the phase bit. Edited December 7, 2008 by potatohead Quote Link to comment Share on other sites More sharing options...
Cybernoid Posted December 7, 2008 Share Posted December 7, 2008 NTSC artifacting: Hard Hat Mack by Michael Abbot release by Electronic Arts. Bug Off High Rise by Joe Calabrese Atari World (3d plotter) DISK023B.zip Jawbreaker Malpass Micro League Baseball Quote Link to comment Share on other sites More sharing options...
oracle_jedi Posted December 7, 2008 Share Posted December 7, 2008 Well,this was a theme in the "Atari vs. Commodore" thread, but I think we should have it in a separate topic... So please post all your info about A8 artifacting here. I will start with a simple (incomplete!) list of A8 titles that use artifacting - maybe someone can help me to complete this list... ?!? NTSC artefacting programs on the A8: - AE by Broderbund *** - Choplifter by Broderbund (cart and disk; the cart by Atari uses 4-color Gr. 15) - David`s Midnight Magic by Broderbund (disk) *** - David`s Midnight Magic by Atari (cart.) - Drol by Broderbund (disk) *** - Head over Heels by Hitsquad/US-Gold - Lode Runner by Broderbund (disk) - Lode Runner by Atari (cart.) - Pinball Construction Set by ECA (and all pinballs created with it!) *** - (most) Sierra online Hi-Res Adventures, like The Dark Crystal and ... - Threshold by ??? - Ultima 1 ? by Origin (not sure if it uses artifacting, since I have never seen it) - Ultima 2 ? by Origin (not sure if it uses artifacting, since I have never seen it) - Ultima 3 by Origin - Ultima 4 by Origin *** there are also cracked + patched versions of these programs in 4-color gr. 15 mode available... PAL artefacting programs on the A8: - Artifacting Character Editor by Joel Goodwin (Page 6, issue 52, pages 18-21) - Runaround by Joel Goodwin (Page 6, issue 53 ?) greetings, Andreas Koch. Flight Simulator II Quote Link to comment Share on other sites More sharing options...
carmel_andrews Posted December 7, 2008 Share Posted December 7, 2008 The pool game someone mentioned was released under 2 different titles by the same company....Pool 400 or Pool 1.5 (both req'd a translator to work with xl/xe mc's) and both were published by IDSI (whatever that stood for) I dunno if the emulator version is buggy but the versions i have for a800win+ have corrupted gfx or don't run properly even in 400/800 mode Perhaps someone has a version that works properly As i said elsewhere though, Artifacting modes on Pal or Non NTSC mc/s don't work so well (probably something to do with the high rez mode needed for artifacting and colour distribution on PAL and NTSC systems) Quote Link to comment Share on other sites More sharing options...
Crazyace Posted December 7, 2008 Share Posted December 7, 2008 I think the biggest problem with artifacting is the difference between PAL and NTSC.... One problem with the Apple II was that it didn't work in Europe until a graphics card was added. At least with the standard colours the 8 bit games ran world wide ( 50/60Hz was a different issue ) Quote Link to comment Share on other sites More sharing options...
Ross PK Posted December 7, 2008 Share Posted December 7, 2008 (edited) What does artifacting mean? Edited December 7, 2008 by Ross PK Quote Link to comment Share on other sites More sharing options...
Warriorisabouttodie Posted December 7, 2008 Share Posted December 7, 2008 Tower Topler also used artifacting. Quote Link to comment Share on other sites More sharing options...
Bryan Posted December 7, 2008 Share Posted December 7, 2008 Working in assembly language meant drawing those patterns. The graphics screen is 40 bytes wide, 7 pixels per byte, with the most significant bit being the phase shift bit. (first real color cell, IMHO!) In APPLE BASIC, the user could just ask for colors, and the graphics would be drawn in that color. If there is a phase bit conflict, last draw wins! This can be easily seen by drawing a cyan rectangle, then plotting a blue line through it. The graphics routines would boil down the color and position request to the nearest artifacted pixel. Really, there were just pixels. Monochrome pixels. The color circuit would either slightly delay them or not, and the position of the pixel gave the color, and that's it for the Apple. 7 pixels per byte, and if you put two of them next to one another, on or off, they would be black or white. Plot them alone, and they would be one of 4 possible colors, depending on the state of the phase bit. Ah, so it made you do the work but if you had a monochrome monitor, I imagine you could just use the whole resolution. Quote Link to comment Share on other sites More sharing options...
Bryan Posted December 7, 2008 Share Posted December 7, 2008 What does artifacting mean? There's been a lot posted about it in the Commodore v Atari thread. It was a trick used to fool the TV into displaying more colors in the high-res mode. Quote Link to comment Share on other sites More sharing options...
Goochman Posted December 7, 2008 Share Posted December 7, 2008 I dont believe Ultima I used artifacting unless there are 2 versions. It uses a chunky colored char mode. Quote Link to comment Share on other sites More sharing options...
potatohead Posted December 7, 2008 Share Posted December 7, 2008 Working in assembly language meant drawing those patterns. The graphics screen is 40 bytes wide, 7 pixels per byte, with the most significant bit being the phase shift bit. (first real color cell, IMHO!) In APPLE BASIC, the user could just ask for colors, and the graphics would be drawn in that color. If there is a phase bit conflict, last draw wins! This can be easily seen by drawing a cyan rectangle, then plotting a blue line through it. The graphics routines would boil down the color and position request to the nearest artifacted pixel. Really, there were just pixels. Monochrome pixels. The color circuit would either slightly delay them or not, and the position of the pixel gave the color, and that's it for the Apple. 7 pixels per byte, and if you put two of them next to one another, on or off, they would be black or white. Plot them alone, and they would be one of 4 possible colors, depending on the state of the phase bit. Ah, so it made you do the work but if you had a monochrome monitor, I imagine you could just use the whole resolution. Exactly. In fact, that's what my group did when we first ended up on the things. Had only the green screens. Way back then I thought the dot patterns were there to simulate colors as some kind of crude texture, until we got color screens! LOL!!! Quote Link to comment Share on other sites More sharing options...
potatohead Posted December 7, 2008 Share Posted December 7, 2008 (edited) What does artifacting mean? Artifacting is where elements of the graphic image you see are not directly produced by the machine in question, but instead are a result of the process used to build the display to your eye. If you plot a pixel on a monochrome device, you are gonna just see a pixel. If you look close, you might see stuff other than that pixel. Maybe it's smudged, or there is ghosting, or if it's moving and the contrast and brightness are cranked, you might see a trail. Those things are artifacts of the display process. Artifacting then is taking that and using it to your advantage. On a color display, that same single pixel might appear to be a colored one because it's too small to be resolved as monochrome due to the color resolution of the display in question. (and that's why we've got stuff like s-video and component!) Computer monitors today don't generally do this kind of thing. They are built with sufficient resolution so as to avoid all but the smallest of artifacts. As for a tiny bright white pixel and you will get it! On ordinary TV's, the color resolution is LESS than the monochrome resolution. In fact, when color TV was first released here in the US, there was significant discussion about the loss of sharpness for monochrome broadcasts. Those typically exceeded 500 horizontal lines, and looked quite good. If you've ever wondered about the patterns worn by screen actors in those broadcasts, this is why! When the programs were made, resolution was high enough to differentiate the patterns, and there were no significant artifacts. Being monochrome, the patterns brought some texture and depth to the scene that was more appealing than just the solid grey shades. Color TV's have at their baseline 160 pixels of color resolution. That's the native Atari color resolution. Color TV's can display 300 to 400 lines of monochrome resolution, and newer ones 600 or more. Improvements in the encoding of video brings us color resolution to 320 pixels or so, and that's what we see on a newer, analog NTSC telly today. That's done by alternative lines shown on even and odd frames, interlacing, and is the source of the dot crawl you will see on your typical TV Newscast. Ataris don't use the newer interlaced timings possible. The C64 uses a split the middle clever timing that brings it's color resolution to the 320 pixels, and because of that it does not artifact well, but on the flip side, it can display a single pixel at the 320 pixel resolution, with few to no significant artifacts. The Atari has the fixed timing, so in GR.8 even pixels are one color, odd pixels are another color, and two together, anywhere are white! That's also why there are very few single pixels in the Atari Text font, and also why it's white on blue. That combination keeps any artifacts to a bare minimum, and when they do occur, they are mostly bluish, leaving us with a clear text display on mostly crappy TV's. I've maintained an interest in this since I was a kid. I just think it's cool. Color resolution on computers with simple video timing, like the Atari, through artifacting boils down to how many pixels they can plot in what Atari people would call a single color pixel. (160 pixel resolution) If the horizontal resolution of the graphics sub-system of the computer is 320 pixels, you are gonna get 2 artifacted colors easily. If it's 640, then you get maybe 8 - 12. It all depends on how many little pixels you can get the machine to output and their relation to one another. That's for one luma or brightness option. If you've got lots of those, then you multiply the available colors by that for the total The CoCo III, for example, had 640 pixel color display capability. That's meant for s-video, or an RGB monitor. If you drive it through an ordinary TV, you can get nearly 256 colors at 160 pixel resolution! It had lots of lumas. 8 or 16. Can't remember now. Another thing about the A8, where artifacting is concerned, is how it does it with colors. If you ask for a dark red background, you can artifact a lighter red, and a green. If you ask for a dark green background, you can get a brighter blue-green, and a really bright green or yellow green, depending. All of that is NTSC of course The Atari has 15 hues and 15 lumas in GTIA mode. For each hue, a little chroma pixel appears, that is 1/16th of a color pixel thus: xxxxxxxxxxxxxxxx ---> white pixel --0------------------- ----> hue 3 --------o------------- ----> another different hue One thing I've noted is that the size of these varies somewhat. If you go toward the yellows, they are larger, and if you go toward the reds and blues, they are smaller. Don't know the source of that, but I do know that on systems where they are all the same size, the yellow pixels have a lot of texture to them. They don't look as solid as Atari ones normally do. Always wondered if Jay Miner didn't consider that when laying out the pixels, or if it just happened. Edited December 7, 2008 by potatohead 1 Quote Link to comment Share on other sites More sharing options...
potatohead Posted December 7, 2008 Share Posted December 7, 2008 I dont believe Ultima I used artifacting unless there are 2 versions. It uses a chunky colored char mode. I must be thinking of III then. I'm positive II had it. Played the crap out of that one. Quote Link to comment Share on other sites More sharing options...
ClausB Posted December 7, 2008 Share Posted December 7, 2008 Artifacting is.... Wow! Very nice explanation without getting into the deep math of color subcarriers, phase encoding, frequency interleaving, and such. The Atari has 15 hues and 15 lumas in GTIA mode. For each hue, a little chroma pixel appears, that is 1/16th of a color pixel thus: xxxxxxxxxxxxxxxx ---> white pixel --0------------------- ----> hue 3 --------o------------- ----> another different hue One thing I've noted is that the size of these varies somewhat. Really? I always thought that the chroma signal had 50% duty cycle, that is, the "chroma pixels" were 1/2 of a "color pixel", and that only the phase varied with hue. Quote Link to comment Share on other sites More sharing options...
Bryan Posted December 7, 2008 Share Posted December 7, 2008 (edited) Artifacting is.... Wow! Very nice explanation without getting into the deep math of color subcarriers, phase encoding, frequency interleaving, and such. But it's not really that accurate either. When unintended colors appear on the edges of images on a TV, we call it artifacting because an analog TV isn't capable of producing exactly what it's been asked to. Extra artifacts appear in the picture. However, when we put pixel patterns on the screen to produce color it isn't a color produced out of errors, but rather color produced by the TV doing what it's supposed to do. With analog video, color comes from providing the TV a signal at a specific frequency. On the Atari you can create that exact frequency using pixel patterns. So artifacting is a bit of a misnomer. Was it a good idea for Atari to use the color frequency as a pixel clock? I'm not sure, but it made the hardware simpler. (Before some assaults me, I should mention that the PAL Atari has separate pixel/color clocks so you won't get the same effect as on NTSC machines) Edited December 7, 2008 by Bryan Quote Link to comment Share on other sites More sharing options...
emkay Posted December 7, 2008 Share Posted December 7, 2008 The ironic thing is that the GTIA generates perfect luma and chroma signals. The circuitry behind it makes the signal worse. Not to mention that they forgot to connect the chroma to the video out connector in the XL series. With some "cents" of hardware cost you can produce a nice signal out of the A8 that a new TFT smiles satisfied for it Quote Link to comment Share on other sites More sharing options...
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