Question about my color chart. What do you think?

[+Random Terrain]

The color chart I have is made up of colors from z26 and I see that colors from Stella are a little different (usually brighter). Is one emulator closer to what you get on a real Atari?

 

<span style='font-size:14pt;line-height:100%'>Here's the most important question:</span>

I can easily split the color bars you see in my chart to show colors from both emulators. Does that sound like a good idea to you or should I just stick with colors from one emulator and forget the other one?

Edited December 17, 2007 by Random Terrain

[SeaGtGruff]

The color chart I have is made up of colors from z26 and I see that colors from Stella are a little different (usually brighter). Is one emulator closer to what you get on a real Atari?

 

Here's the most important question:

I can easily split the color bars you see in my chart to show colors from both emulators. Does that sound like a good idea to you or should I just stick with colors from one emulator and forget the other one?

908050[/snapback]

 

I'd go with showing two or three color charts-- one for z26, one for Stella, and even one for PCAE (which, if I remember correctly, uses colors which are a little different from z26 and Stella). That way, we can compare the colors for the various emulators, to be sure our colors will look good no matter which emulator people play our games on.

 

Also, you might add color charts for PAL and SECAM, too (especially PAL).

 

By the way, here are two programs I wrote to display all of the Atari's colors at once. The first one shows the 128 colors arranged in an 8x16 grid, and the second one uses screen-flipping to get in-between luminances, for a total of 240 colors. You can also use screen-flipping to get in-between hues, or in-between hues *and* in-between luminances.

 

Michael Rideout

128COLRS.BIN

240COLRS.BIN

[danwinslow]

Yah, I agree with SeaGtGuff. By the way, hella nice work on the help pages, RT.

[+Random Terrain]

I'd go with showing two or three color charts-- one for z26, one for Stella, and even one for PCAE (which, if I remember correctly, uses colors which are a little different from z26 and Stella). That way, we can compare the colors for the various emulators, to be sure our colors will look good no matter which emulator people play our games on.

 

Also, you might add color charts for PAL and SECAM, too (especially PAL).

 

By the way, here are two programs I wrote to display all of the Atari's colors at once. The first one shows the 128 colors arranged in an 8x16 grid, and the second one uses screen-flipping to get in-between luminances, for a total of 240 colors. You can also use screen-flipping to get in-between hues, or in-between hues *and* in-between luminances.

908083[/snapback]

Thanks. I could have used that first one to get the colors. I took 128 screen shots twice (z26 and Stella). I'll have to download PCAE. I'd like to keep the colors all in one chart and I can see having room for three, but 4 might be too much so anyone using PAL colors will have to go to pages like this:

 

http://www.qotile.net/minidig/docs/tia_color.html

 

 

Yah, I agree with SeaGtGuff. By the way, hella nice work on the help pages, RT.

908087[/snapback]

Thanks.

[+Random Terrain]

Does anyone know how to make PCAE work on a Windows XP computer? The documentation doesn't seem to mention that. And what a pain to download. You have to sign up with some lame web site before they will let you download it, then you have to turn off your pop-up blocker for the download window to come up. Too much trouble for a program that some people say isn't very good compared to Stella and z26.

 

I found two web sites that claimed to have pcaewin, but both copies wouldn't run because of some kind of error.

 

Does anyone have some version that they know works on a Windows XP computer?

Edited August 10, 2005 by Random Terrain

[s0c7]

You can try this one. It works on Win2k which usually means it'll work on XP. It's old and seems to not be as accurate as z26 and Stella (example: when playing my game the asm portion doesn't seem to work. The jets are in the foreground and the clouds are in the background. The opposite is true with the other emus).

Edited August 11, 2005 by s0c7

[vdub_bobby]

By the way, here are two programs I wrote to display all of the Atari's colors at once. The first one shows the 128 colors arranged in an 8x16 grid, and the second one uses screen-flipping to get in-between luminances, for a total of 240 colors. You can also use screen-flipping to get in-between hues, or in-between hues *and* in-between luminances.

 

Michael Rideout

908083[/snapback]

Those are some really nice looking binaries.

[+Random Terrain]

You can try this one.  It works on Win2k which usually means it'll work on XP.  It's old and seems to not be as accurate as z26 and Stella (example: when playing my game the asm portion doesn't seem to work.  The jets are in the foreground and the clouds are in the background.  The opposite is true with the other emus).

 

EDIT: Helps to attach the file.  D'oh!

908235[/snapback]

Thanks, but I get one of those "pcaewin.exe has encountered a problem and needs to close. We are sorry for the inconvenience." I'll just forget about pcae since it sucks compared to Stella and z26 anyway.

[+stephena]

The color chart I have is made up of colors from z26 and I see that colors from Stella are a little different (usually brighter). Is one emulator closer to what you get on a real Atari?

 

Here's the most important question:

I can easily split the color bars you see in my chart to show colors from both emulators. Does that sound like a good idea to you or should I just stick with colors from one emulator and forget the other one?

908050[/snapback]

The current version of Stella (1.4.2) can use the z26 palette as well. Try pressing 'Ctrl-P' while a game is running. It will switch between the default, the Stella 1.1 version (which is totally incorrect, but some people seem to like it), and z26.

 

If at some point it's determined that the z26 palette is more accurate, I have no problem with making it the default in Stella. In fact, after the next release I plan to add a palette editor directly into the emulator, so one can fine-tune the palette to their liking.

 

Steve

[+Random Terrain]

If at some point it's determined that the z26 palette is more accurate . . .

908524[/snapback]

I doubt that it is. I'm almost done updating my color chart and Stella colors look closer to me. For example, Stella yellow looks more like official Atari 2600 yellow. And I remember the reds being more like Stella colors too. z26 colors seem odd and darker than how the real ones looked on the color TVs I used over the years to play Atari 2600 games on.

[SeaGtGruff]

If at some point it's determined that the z26 palette is more accurate . . .

908524[/snapback]

I doubt that it is. I'm almost done updating my color chart and Stella colors look closer to me. For example, Stella yellow looks more like official Atari 2600 yellow. And I remember the reds being more like Stella colors too. z26 colors seem odd and darker than how the real ones looked on the color TVs I used over the years to play Atari 2600 games on.

908530[/snapback]

 

One thing to keep in mind is that the color on a real Atari can be greatly influenced by the color TV, especially the tint/brightness/contrast settings.

 

Some years ago, I ran an 8-bit Atari computer through a VCR so I could hook it up to a Snappy screen capture device on my computer, and I captured actual Atari screenshots of all the colors-- the 16 luminances of all 16 hues (one hue at a time), plus a screen display I had created which shows all 256 colors at once. I'm posting a bitmap of the 256-color screenshot, so you can compare it with the palettes of the Stella, z26, PCAE, and other emulators. Unfortunately, on a real Atari the colors aren't very "solid," because NTSC television has such a problem with color stability (hence its nickname, "Never The Same Color").

 

Anyway, I hope this helps!

 

Michael Rideout

256color.bmp

[+Random Terrain]

Anyway, I hope this helps!

908905[/snapback]

Thanks. After comparing the images and knowing that Atari on video looks darker and crappier, between Stella and z26, I think Stella is closer for the most part.

[SeaGtGruff]

Hang on, that bitmap may be one I cobbled together from 16 separate ones, but I did have a program which displayed the same thing. The problem is, my hard drive had crashed, so I had to type a simple program to create the images which I captured, and I don't think I had typed in the program that used DLIs to display all 16 hues at once. (Incidentally, the way I got the black border on all of the lines was to position some black players on either side of the color grid, as otherwise each line would have luminance 0 of the hue being displayed, instead of black.)

 

I do have a complete set of other screenshots, though, and I can zip them up and e-mail them to you if you wish. One set is 16 screenshots, with each screenshot showing all 16 luminances of a given hue, displayed as vertical stripes. The other set is 8 screenshots, with each screenshot showing all 16 hues of a given (even) luminance, again displayed as vertical stripes. However, the GTIA mode which can display all 16 hues at once does not display shades of gray; hue 0 is always black, no matter what luminance the other hues are being displayed in.

 

And of course, the 2600 can't display the odd-numbered luminances, so if you are applying these screenshots to the 2600, you should ignore the 128 odd-numbered color values.

 

I had tried to use the screenshots to determine the ideal RGB values for all 256 colors, but the grainy images drove me crazy. For example, I had also captured some screens showing single colors, but when I loaded them into a graphics program, it said there were hundreds, thousands, or even millions of different colors being used in each image!

 

Michael Rideout

[+Random Terrain]

I do have a complete set of other screenshots, though, and I can zip them up and e-mail them to you if you wish. One set is 16 screenshots, with each screenshot showing all 16 luminances of a given hue, displayed as vertical stripes. The other set is 8 screenshots, with each screenshot showing all 16 hues of a given (even) luminance, again displayed as vertical stripes. However, the GTIA mode which can display all 16 hues at once does not display shades of gray; hue 0 is always black, no matter what luminance the other hues are being displayed in.

You can if you want or you can just post them like you did the other if you have the time.

 

 

I had tried to use the screenshots to determine the ideal RGB values for all 256 colors, but the grainy images drove me crazy. For example, I had also captured some screens showing single colors, but when I loaded them into a graphics program, it said there were hundreds, thousands, or even millions of different colors being used in each image!

Whenever I have that problem, I usually soften the area until there is only one color. Most of the time it looks like the original color too.

[SeaGtGruff]

Anyway, I hope this helps!

908905[/snapback]

Thanks. After comparing the images and knowing that Atari on video looks darker and crappier, between Stella and z26, I think Stella is closer for the most part.

908913[/snapback]

 

You may be right about that, although one thing I've noticed is that Stella seems to use more idealized colors. What I mean is that, for example, the 2600 can't show color 15 (hue 0, luminance 15), which is the brightest white on the 800. Yet if I remember correctly, Stella shows color 14 (brightest white on the 2600) as pure white, when it should actually be a very light gray (just a tad darker than white).

 

This isn't really a problem with 2600 emulators, because we could just pretend that we've adjusted the brightness and contrast to get pure white for color 14. But on an 800 emulator, some palettes give pure white for both color 14 and color 15, which is a problem if you're trying to use the GTIA mode that shows all 16 of the luminances, since colors 14 and 15 come out as the "same" color.

 

Ideally, I would prefer color 14 to be displayed as not-quite-white on any Atari emulator (2600 or 800, or even 7800). But more significantly, the palettes for some emulators don't always reproduce the other hues as closely as I'd like.

 

Color was always my biggest obsession with the Atari computers, so I spent a lot of time trying to get more colors through flickering and so forth. If the hues are not reproduced closely enough on an emulator, it can adversely affect the results of flickering between two colors to get a third color. For example, certain values of yellow and blue can be flickered to get light green, but the results can vary a lot depending on the emulator's palette versus the real thing. Of course, the biggest difference may be using a color TV versus a computer monitor, because colors tend to blur together better on a TV than on a monitor. Consequently, any game which relies on flickering to get more colors will need to be programmed carefully when using an emulator, because the final result may look completely different when the finished game is played on a real Atari.

 

Michael Rideout

[+Random Terrain]

You may be right about that, although one thing I've noticed is that Stella seems to use more idealized colors. What I mean is that, for example, the 2600 can't show color 15 (hue 0, luminance 15), which is the brightest white on the 800. Yet if I remember correctly, Stella shows color 14 (brightest white on the 2600) as pure white, when it should actually be a very light gray (just a tad darker than white).

<{POST_SNAPBACK}>

If you can go by what I got for my chart, the Stella color is #ECECEC (236, 236, 236).

Edited December 17, 2007 by Random Terrain

[SeaGtGruff]

You can if you want or you can just post them like you did the other if you have the time.

 

Okay, here are two zipped files-- one with 16 screenshots, each with all 16 (Atari 800 GTIA) luminances of a given hue; and the other with 8 screenshots, each with all 16 hues for a given even-numbered luminance (except hue 0 is always black). But be warned, these zipped files are rather large.

 

Michael Rideout

16hues.zip

8lums.zip

[+Random Terrain]

Okay, here are two zipped files-- one with 16 screenshots, each with all 16 (Atari 800 GTIA) luminances of a given hue; and the other with 8 screenshots, each with all 16 hues for a given even-numbered luminance (except hue 0 is always black). But be warned, these zipped files are rather large.

908939[/snapback]

Thanks. I have a pretty fast connection now so large files don't scare me anymore.

[SeaGtGruff]

Here is one more screenshot that I found, which is from a program I wrote using an Atari 800 emulator showing all 128 even-numbered colors. I had even added labels to show the luminance and hue values. The palette should be very similar to at least one of the Atari 2600 emulators. In fact, you could chop off the emulator window in a graphics editor, and replace (or fill) the colors with the ones from the 2600 emulator of your choice.

 

In particular, notice how hue 15 is a definite brown in this image, whereas hue 15 in my other 256-color image from an actual Atari XE computer is more of a green or slightly-brownish-green. I haven't used Snappy in a long time, so I don't recall if I'd adjusted the tint at all. I think I used the default settings, so the colors would be as "true to life" as possible.

 

Michael Rideout

128color.bmp

[+Random Terrain]

Thanks. I'll go through these after I wake up.

[SeaGtGruff]

By the way, here are two programs I wrote to display all of the Atari's colors at once. The first one shows the 128 colors arranged in an 8x16 grid, and the second one uses screen-flipping to get in-between luminances, for a total of 240 colors. You can also use screen-flipping to get in-between hues, or in-between hues *and* in-between luminances.

I never really liked the way my 240COLRS.BIN program displayed the colors off-center, so I just redid it to get a much better picture. Although it's written in assembly, I used batari Basic-- call me lazy, but I find it convenient to write little assembly programs in batari Basic, because I can bang out the code without worrying about the processor line, the include lines, the ORG, the vectors, etc. Of course, that means I have much less room for my code, since batari Basic's own routines will be compiled into the program by default, but that's okay as long as I'm just writing a little utility, demo, or test program.

 

I used the playfield and the ball to cover up the extra pixels of color on the left and right sides of the display, so I wouldn't have to worry about changing back and forth between the gray "border" color and the palette colors. And I used eight bytes of RAM to store the eight luminances of the hue being drawn, so I could use the same subroutines to draw the lines for each hue. Also, loading each of the color values from zero-page RAM works out better for the timing, because it means each load-store takes 6 cycles, or 18 color clocks, so shifting the color changes back and forth by 3 cycles (or 9 color clocks) from line to line produces 15 blocks of color that are each 9 pixels wide, or 135 pixels in all, which leaves room for 13 gray pixels on the left, and 12 gray pixels on the right, for a nice border.

 

Michael

 

 

240_Colors.bas

 

240_Colors.bas.bin