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mike_cc
19th July 2012, 08:20
This still rates as my favourite all time paint program, and the one I cut my teeth on, but has anyone had this issue?

I've tried changing everything I could think of in the Format menu in PP and the screenmodes in WinUAE, but I cannot get square pixels!

hooverphonique
20th July 2012, 09:45
assuming you're running fullscreen, the resolution aspect ratio must match the width/height aspect ratio of your monitor.. also, depending on resolution, the fact that your monitor may not have square pixels hardware wise may have an effect..

the easiest way to solve your problem is just to think about where it could be wrong - it's all simple math, really..

bdb
20th July 2012, 15:19
He's right, you would need a resolution that was 1:1 not 4:3 nor 16:9

Even if you were able to get a 600X600 screen, the monitor would open on a standard (usually VESA) back ground window of like 800x600 thus distorting the pixels anyway. If you went really Retro, you could get a Matrox Display board and corresponding monitor from the 1970's which ran on a PDP/11 and was a display, not a monitor; they were 256x256 in 16 colors and cost about $3 - 5,000 at the time; you wrote to the board and took a picture of it as hard copy with a Polaroid camera. The screen was about 10X10"

mike_cc
20th July 2012, 15:36
assuming you're running fullscreen, the resolution aspect ratio must match the width/height aspect ratio of your monitor..

You'd think so wouldn't you.


also, depending on resolution, the fact that your monitor may not have square pixels hardware wise may have an effect..

Can monitors have non-square pixels that rotate so they are non-square one way, and then non-square the other way? Are you playing with me?


the easiest way to solve your problem is just to think about where it could be wrong - it's all simple math, really..

You mean like the ratio between 1920 and 1080 is 1.7r and that the smart money would be to try and replicate that within the program, either first by making sure all the screenmodes in WinUAE were correct and then by experimenting with every possible screen and image size in PPaint?

Or did you mean that aspect ratios are simple math? Or that telling Ppaint an image size you'd like to try and it applying some arcane principle to your command that either carrys it out or doesn't?

Just to reiterate. I've played with as many settings regarding aspect ratio as I can, and I've messed around with windowed/non-windowed settings in WinUAE too. But between the Ppant screenmodes, my 16:9 1920x1080 monitor, WinUAE settings and my general lack of infinite time (or patience), I was hoping to luck out and find someone who'd already faced this issue and solved it, or who is more savvy than I am with screenmodes/ppaint. I don't see my old 4:3 monitor as an effective solution.

---------- Post added at 15:36 ---------- Previous post was at 15:26 ----------


He's right, you would need a resolution that was 1:1 not 4:3 nor 16:9

Even if you were able to get a 600X600 screen, the monitor would open on a standard (usually VESA) back ground window of like 800x600 thus distorting the pixels anyway. If you went really Retro, you could get a Matrox Display board and corresponding monitor from the 1970's which ran on a PDP/11 and was a display, not a monitor; they were 256x256 in 16 colors and cost about $3 - 5,000 at the time; you wrote to the board and took a picture of it as hard copy with a Polaroid camera. The screen was about 10X10"

Right but the difference is that pixels are all square. If a monitor was 4x3 like before widescreen, and it had 800x600 resolution, that's 4x3. Which means that the representative pixels on screen are square, or as close as matters.

Pixels are always considered square for purposes of computer art, pixelated widgets and such, but otherwise you have a whole mess of problems when moving things around between systems.

A 16:9 monitor has 16 pixels across for every 9 that go up. Meaning, again that they are square pixels.

So here's the relevant bit. If WinUAE is displaying in a 1920x1080 window, I need to find a screenmode in full screen Ppaint of this aspect ratio. I suppose that's what I was getting at all along. Because I seem to remember ppaint throwing all sorts of pixel shapes (oblongs, not stars or ovals, to be fair), but a 640x512 image had square pixels. No longer is that true on a 16:9 screen but I would have thought I could just tell ppaint to display a resolution of image or a resolution of screen that would compensate. All that's happening is, sometimes ppaint allows this and you get something closer to square, and sometimes ppaint completely ignores your command to change resolution.

All this discussion is helping though. I'm pretty much resolved to just run WinUAE in a 4:3 box with black bars (well, windoze desktop) on either side of it. I'll let you guys know if that works.

Cheers.

ajk
21st July 2012, 09:13
Well there's a simple reason really, none of the original native Amiga screenmodes are 16:9, because the whole widescreen TV concept didn't really exist back then. You would need to set up an RTG wide screenmode or maybe one of the HighGFX type modes (not sure if usable within WinUAE) and use that, or stick with 4:3.

Also remember that in Workbench non-square (2:1 tall) pixels were in fact the norm. And 640x512 isn't 4:3 if represented with square pixels.

bdb
21st July 2012, 19:33
There is a difference in each "picture element" the monitor hardware puts on the screen and the "pixel" that the graphics card tells the monitor to display; the monitor dot is round, although a "mask" is often used the change it to another shape (Sony Trinitron); the mask shape cannot be changed, but redefined by combining the picture elements into another shape. Now that can be changed and now that monitors communicate with their graphics cards as to their morphology, it then becomes incumbent that the two in combination define a. "square" versus a "rectangular" pixel. Still cards and monitors want to conform to known standards in commercial computer applications (VESA) and while it may be possible to define another "square" display, how then do you make sure the target audience has that setup?

Oh, the Trinitron mask is a taller-than-wide rectangle

hooverphonique
23rd July 2012, 15:51
Can monitors have non-square pixels that rotate so they are non-square one way, and then non-square the other way? Are you playing with me?What do you mean by that? when something is said to be "square", you're saying something about both sides in relation to each another - you cannot have something two-dimensional that is non-square and then not non-square after rotation. And no, monitors don't have rotating pixels ;-)


A 16:9 monitor has 16 pixels across for every 9 that go up. Meaning, again that they are square pixels.I would have to disagree.. 16:9 means that the width/height ratio of the physical display area is 16 to 9, it doesn't say anything about the pixel shape or the resolution..

bdb
23rd July 2012, 20:54
Hooverphonique,

I'm afraid you are correct, but the thread has lost sight of the trees in trying to define a new forest. Any screen format is a generalization of ratios of width to height, not a defination of picture element shape. This shape on the "elemental level" is a property of: the "Mask" used to make the "dot" not a dot, but a defined shape which can be addressed; this may be a set of 4 shaped-dots to form a "pixel" that may, or may not be square. For example, if you put a "Square Box" on the end of a flashlight, does if form a square beam of light? If four such flashlights are grouped together are they a square? The classic example is the X-Ray used to take a picture of a bone; the x-rays come out of the tube spreading out all over in a circular pattern, however a lead box with long straight columns is used to "columnize" the x-rays into a bunch of straight lines that takes a sharp-ish image of the bone.

The "mask" applied to a monitor dot is no way near that long and then the "dots with regular corners" are grouped to form an addressable pixel. Is this now square? If one could put their retina up against the screen it might appear so, but there are lenses, distortions, and the laws of optics that then are "seen" by the visual cortex in the posterior brain.

I suppose that, "IF YOU BELIEVE THAT IT IS SQUARE, THEN IT MUST BE SQUARE." Damn the physics, full speed ahead!
.

Ratte
4th August 2012, 19:29
Well there's a simple reason really, none of the original native Amiga screenmodes are 16:9, because the whole widescreen TV concept didn't really exist back then. You would need to set up an RTG wide screenmode or maybe one of the HighGFX type modes (not sure if usable within WinUAE) and use that, or stick with 4:3.

Also remember that in Workbench non-square (2:1 tall) pixels were in fact the norm. And 640x512 isn't 4:3 if represented with square pixels.

HD720 (part of highgfx) is 16:9
1280x720 / 640x360
;)

mike_cc
5th August 2012, 22:39
the thread has lost sight of the trees in trying to define a new forest.
.

Thanks bdb, that's the thing. I clearly got out of my depth in trying to discuss the tech specs of displays. I'm more used to talking about tvs and on a telly, if it is a full hd, it will have at least 1920x1080 pixels, although often more. My point was far more simple than all the tech talking required though. If a telly, or any kind of screen has the same ratio of pixels up and across, as the aspect ratio of the screen size (like how 16:9 size is the same ratio as 1920x1080), and you draw what appears to be an accurate square with equal sides in an art program, then the perpendicular sides will have the same pixel count. There will be less space above and below the square, on the screen, as there will be to the left and right of the square. The point about number of pixels is distracting though, because, like bdb is saying, it's about what is represented on screen that really concerns.

For example, I fired up ppaint again today after I put my A1200 back together and on a 4:3 TV, displaying ppaint in 640x512, the image pixels appear square (square enough for a ham fisted amateur like me anyway!). But the screen flickers.

In WinUAE, and on a 16:9 HD monitor, I spose the answer is that I need to find some aspect ratio that ppaint can kick out which makes the pixels appear the same kind of square. The problem I find is that ppaint doesn't want to play. I was attempting to compensate for the wider screen but the program settings didn't make any difference and it was made harder as I couldn't completely customise the screen or image size. Back on the old CRT telly, higher resolutions would be a problem as the output at higher resolutions/scan rates, flickers on the screen. But my lovely Benq monitor eats that up and poops it out, so I ought to be able to use whatever resolution (within reason) that I like.

Hope that's clearer. Rather than understanding the fundamentals of screen design, I'm looking for a pragmatic solution, that works within UAE on my pc.

Retrograde
5th August 2012, 23:24
Hope that's clearer. Rather than understanding the fundamentals of screen design, I'm looking for a pragmatic solution, that works within UAE on my pc.

I don't know what you can configure on an Amiga in the way of custom resolutions (I never used anything else but what the particualr flavour of Workbench presents to me), but when running old games at least on the PC I can set my 16:10 monitor to display a 4:3 picture explicitly, check around in your monitor menus, you just might have the same option.

mike_cc
7th August 2012, 08:00
Hope that's clearer. Rather than understanding the fundamentals of screen design, I'm looking for a pragmatic solution, that works within UAE on my pc.

I don't know what you can configure on an Amiga in the way of custom resolutions (I never used anything else but what the particualr flavour of Workbench presents to me), but when running old games at least on the PC I can set my 16:10 monitor to display a 4:3 picture explicitly, check around in your monitor menus, you just might have the same option.

That sounds pragmatic enough! Could be a workable solution and only requires a second or two to try. I'll try that tonight. Cheers :D