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Horizontal/vertical image rotating PCB

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Tornadoboy

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This might be a stupid idea as I don't know enough about video signals to know if it's feasible, but would it be possible to make a PCB that can flip, rotate and adjust video images so like a horizontal game can fit on a vertical, and vice versa, etc? It would be terrific if there was an option to put both vertical and horizontal games in the same cabinet as it would free up space and/or you wouldn't have to go as far as building a physically rotatable monitor.
 
Tornadoboy said:
This might be a stupid idea as I don't know enough about video signals to know if it's feasible, but would it be possible to make a PCB that can flip, rotate and adjust video images so like a horizontal game can fit on a vertical, and vice versa, etc? It would be terrific if there was an option to put both vertical and horizontal games in the same cabinet as it would free up space and/or you wouldn't have to go as far as building a physically rotatable monitor.
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Yes, and if this feature could be added to superguns like the HAS, but sadly no one seems capable of doing it.
 
xtrasmiley said:
Tornadoboy said:
This might be a stupid idea as I don't know enough about video signals to know if it's feasible, but would it be possible to make a PCB that can flip, rotate and adjust video images so like a horizontal game can fit on a vertical, and vice versa, etc? It would be terrific if there was an option to put both vertical and horizontal games in the same cabinet as it would free up space and/or you wouldn't have to go as far as building a physically rotatable monitor.
Click to expand...
Yes, and if this feature could be added to superguns like the HAS, but sadly no one seems capable of doing it.
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You can, but you would also need to the joystick controls as well I think, or maybe not. I know someone did something like this a while back, I think on cps2 hardware.
 
I think the general thinking is this would be for shooters, and such a device would introduce lag, which would make it beside the whole point.
 
Perhaps I'm thinking all wrong here, maybe the route to go is instead of having an external PCB to alter the signal there should be a replacement monitor chassis that alters the way it's displayed by the way the coils are handled? Move around the coil connections and alter their inputs accordingly? A new, universal replacement chassis might be an opportunity to tackle some other annoying issues too like handling weird sync signals, accepting black & white composite input, and even converting medium res to standard so as to work with games like Paperboy?
 
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This would be awesome as a companion to the Naomi netboot .. which has around 6-7 vertical shmup games.

This could be an external pcb that normally acts as a pass through for horizontal signal. Then have the pi (which is already in the set up) send a signal to rotate the vertical games to horizontal.

I would gladly buy one of these .. as would a bunch ton of people who have the same rigs as it would add some awesome games to our horizontal set ups! I guarantee you could not keep these in stock.
 
From a theoretical standpoint it is possible to make a PCB that would rotate an image. However, you would guarantee 1 frame of lag (16ms) minimum. This is unavoidable because of the way the image is drawn left to right, top to bottom. When rotating 90 degrees you would not be able to draw the first line of the rotated frame until you started receiving the last line from the un-rotated frame


A Chassis that was configured to draw an image both ways on a CRT tube wouldn't have the lag problem however you wouldn't be able to modify an existing chassis to do that. The reason being is that the chassis, yoke, and guns within the tube are designed to draw horizontally extremely fast, but draw vertically an order of magnitude slower.... I'm not sure most tubes/yokes could handle drawing the image quickly across the vertical like that. I suppose you could try it out by finding a tube that has similar impedance and resistance values for the horizontal and vertical values on the yoke (no easy task) and then swap the H and V pins on the yoke connector. Chances are even if it works the image would look like hot garbage and you might significantly shorten the lifespan of the monitor, not to mention needing to completely re-calibrate the geometry (if it can even be properly dialed in at all)
 
Pfft i could live with a few frames of lag to gain all those beautiful shmups in the same set up as my horizontal games :)
 
twistedsymphony said:
From a theoretical standpoint it is possible to make a PCB that would rotate an image. However, you would guarantee 1 frame of lag (16ms) minimum. This is unavoidable because of the way the image is drawn left to right, top to bottom. When rotating 90 degrees you would not be able to draw the first line of the rotated frame until you started receiving the last line from the un-rotated frame
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Listen to this man. Requires a frame buffer. Otherwise, a straight forward operation (for someone like marqs or @mikejmoffitt who already play with this stuff).

Solutions for this do exist. Most straight forward is the Silicon Optix "Image Any Place" IA-100 unit. Ultra fancy upscaler from the early 2000's, targeting projectors, and could do all sorts of cool things with the image, including rotation. You can still find them on ebay. I snapped one up after reading Fudoh's nice writeup: https://shmups.system11.org/viewtopic.php?f=6&t=38531
-ud
 
See i dont want one with a scaler or adds scanlines or does anything fancy .. literally i want one that just rotates the image based or a gpio signal from a rpi3 or that you can connect a switch to.
 
If it can get down to 1 frame, that’s probably low enough for the average player to use. What about OSSC vet 2 feature?
 
xtrasmiley said:
If it can get down to 1 frame, that’s probably low enough for the average player to use. What about OSSC vet 2 feature?
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OSSC does not have a frame buffer (output lines are written as input lines are read), which is why performance is so great. Should marqs add a frame buffer, sky's the limit on image manipulation (at the cost of latency).
-ud
 
Correct, a version 2. I guess even an updated FM. It’s time to move into the future!
 
Ah ok .. well niw i understand. Still want one lol
 
Hmm .. that would be awesome .. but not space efficient and would require yet another Naomi netboot rig lol
 
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