FPGA Based Videogame System

[phoenixdownita]

So far no one has considered how the light bounces around and leaks out while being generated in a CRT.

Nobody has considered what happens to the electron after it hits the phosphor dot.

Does it fall down by gravity? Does it go to the electrons heaven?

[Keatah]

Gravity does influence the path. Not in a human detectable way though. More important is the scattering and bouncing off the glass, mask, and other fellow phosphors.

 

As far as the heaven thing goes, that's theology and metaphysics - beyond the scope of this thread I'd imagine.

[Andromeda Stardust]

Having a real CRT is not just for nostalgia. Filters are okay on a LCD, but it lacks the depth of picture, color accuracy and zero input lag found in a CRT. And if you have a CRT above consumer grade, like an Arcade Monitor, PVM or BVM, well then you have something really special and I would use one of those over the LCD for anything that supports 240 or 480 resolution.

Main reason I mentioned "nostalgia" was in response to Schizophretard's question as to why scanlines, CRT mask, composite bleed, and other effects are desirable on modern displays. I agree there is no substitute for a proper tube TV, but working sets will become rare in a few more years as more and more CRTs get binned, so it won't always an option to just go to a thrift store and pick one up for $20-$30. Others cited space issues as well.

 

Kids that grew up with emulation and can now afford to buy old hardware will probably prefer perfectly square or rectangular pixels as that's how they experienced these old games. Old hats that grew up with CRTs and RF connector dongles will prefer a screen that looks like a CRT, so the razor sharp pixels can be off-putting. In the era of 4k, bright colors, and extremely dark black levels, I think simulation of CRT masks could become very close to reality, right down to the RGB phosphors.

[Keatah]

Kids that grew up with emulation and can now afford to buy old hardware will probably prefer perfectly square or rectangular pixels as that's how they experienced these old games. Old hats that grew up with CRTs and RF connector dongles will prefer a screen that looks like a CRT, so the razor sharp pixels can be off-putting. In the era of 4k, bright colors, and extremely dark black levels, I think simulation of CRT masks could become very close to reality, right down to the RGB phosphors.

 

True to a point I suppose. I grew up with RF and B/W. Yet I love emulation as it is today, but I must have some NTSC fuzzies to go with it. Not necessarily full CRT effects. But something to take the razor-sharp edges and perfect squares away. And definitely minimal scanlines. Altirra, Stella, VICE, MAME, do passable jobs.

 

MAME does a passable job with the GLSL/HLSL, but it requires setup. And to meet my personal standards, a side-by-side comparison against the original game.

 

Today's emulated machines feel like how I imagined video-modded consoles would have been, back in the day. Or consoles with "professional" video output would have been. But all in all, I recall going to the arcades back in the golden era of 1981 and oftentimes wishing for a BETTER display. One with less distortions, less imperfections, correct colors, all that stuff. Today I have that.

[Andromeda Stardust]

Nobody has considered what happens to the electron after it hits the phosphor dot.

Does it fall down by gravity? Does it go to the electrons heaven?

Yes, gravity does influence the path of a beam of light. In fact, Einstein's Theory of Relativity was proven based on observations of a solar eclipse event in Australia. Photographic plates were exposed during the total eclipse event and the relative positions of the stars in close proximity to the sun were measured. These were compared to plates taken of this same region of the sky six months apart. The position of the stars measurably shifted due to the sun's massive gravity, thus relativity was proven. When an object gains enough mass that the escape velocity is more than the speed of light, it becomes a black hole and nothing can escape from it's grasp.

[cheater]

the subpixels that you stretch are not pure R G and B if you're doing CRT emulation. They will be a bit off, and they will have some halos around them due to diffraction in the CRT glass

 

 

So far no one has considered how the light bounces around and leaks out while being generated in a CRT.

 

I beg to differ.

 

Unless you mean what happens to the signal before it becomes light. That is, the electron beam. The only way for electrons to "bounce around" the inside the CRT like you say (aka secondary electron emission) is if the crt is hugely miscalibrated. At that point you can't see the picture any more, or there's a huge amount of overscan (and the beam bounces off the side) or the dot is extremely bright (unachievable by most TVs anyways, only happens in oscilloscopes). There are no secondary electrons in TVs except for severely broken ones.

 

Here's secondary emission from a too bright dot. The beam is so intensive it knocks out electrons from the fluorescent screen and they end up falling back on the screen again, kind of like when you toss a large rock into a pond, and that splashes water making projectiles that then fall on the surface of the water again.

 

 

I've never seen a crt monitor or tv that would do that. They simply don't operate at high enough cathode voltages for that effect to happen.

Edited September 17, 2016 by cheater

[cheater]

Yes, gravity does influence the path of a beam of light. In fact, Einstein's Theory of Relativity was proven based on observations of a solar eclipse event in Australia. Photographic plates were exposed during the total eclipse event and the relative positions of the stars in close proximity to the sun were measured. These were compared to plates taken of this same region of the sky six months apart. The position of the stars measurably shifted due to the sun's massive gravity, thus relativity was proven. When an object gains enough mass that the escape velocity is more than the speed of light, it becomes a black hole and nothing can escape from it's grasp.

 

This is at a distance if 150 million km, that is, 75 000 000 000 times more than the signal takes from the cathode to your eyes.

Edited September 17, 2016 by cheater

[veelk55]

I don't feel like going back to reread to figure out what I forgot and/or missed but why exactly is this CRT emulation stuff important? I mean, analog video outputs to an actual CRT TV is suppose to be one of the Zimba 3000's options to my understanding.

Hahaha, I don't blame you for not feeling like going back to re-read, this thread has gotten busy about pixels... in a way I feel guilty for this.

 

As for the CRT emulation look being important, that's a good question despite the fact that I will be using a real CRT most of the time with this.

This is what happens. When you play a videogame system, let's say your GB, GBA, Nintendo DS, 3DS, PSP, PS Vita... anything portable.

The games that are designed for these systems are displaying exactly 1 pixel on an LCD dot.

Chances are, that's the same thing you have on your monitor right now as you read this very thread. (Though I've seen people use the wrong resolution and things look horrible AND they like it that way.)

 

Let me use some examples for pictures.

Right now, what you have on your screen is this:

 

If you get close to it for a second, it is supposed to look clean and in order with your screen's pixels, like this:

 

Imagine that you got a higher resolution monitor, but computers were unable to change resolution at all. It would become something like this:

 

Just look at those dots around the pointer. It is all crooked. Some people don't care about this! But personally, being a graphic designer, I really really don't like this look because simply, the dots that the artists put there carefully and neatly have become a mess now. Think of how 3DS enlarges DS games to fit the screen. That is absolutely horrendous and ruins the original cutting edge sharpness the designers put there.

 

 

When enlarging old games on HD, it will be much nicer than that though. But we will have giant blocky pixels. Its like if your computer looked like either of these 2 pics from now on:

 

On a computer though, we don't have issues like these when browsing the web, because things are designed to fit 1:1 and adjust the spaces between things so that objects remain dot-perfect. That is why it is important to have a CRT-like filter, because videogames can't adjust to the size in the same way, but pixels were never meant to be huge blocky things, they're meant to fit 1:1 with what the screen can physically display. Similar to the zoom in the second picture above with the dots, videogames look much nicer when each pixel, or line of pixels, has its own designated place on the display, rather than an enlarged unnatural look. Big pixels look good occasionally in games when you see objects zooming in like on SNES, but to have everything displayed like that including all fonts and characters, is not as natural looking anymore.

 

 

Nobody has considered what happens to the electron after it hits the phosphor dot.

Does it fall down by gravity? Does it go to the electrons heaven?

 

Intredasing... I think they travel to the brain through your eyes in the form of light. (And everywhere else around you).

What happens after this? They become a memory. No, they don't disappear, almost all (if not ALL) those images still physically exist in your brain as you are still able to recall them. There is currently no way for them to travel further other than for you to physically draw it with your hands to show it to others, until a brain image extractor is invented.

Edited September 17, 2016 by veelk55

[Andromeda Stardust]

 

This is at a distance if 150 million km, that is, 75 000 000 000 times more than the signal takes from the cathode to your eyes.

Yes, and it took measurements across 150Gm (1Gm = 1 billion meters) against an object far more massive than Earth in order to get a reading on gravitational deflection. Maybe the beam across your living room is only distorted a few nanometers by the pull of Earth gravity at most. Boom! Distorted pixels. You may have to shift your head approximately the distance of an atom's width to correct this aberration. If you can perceive this difference, your optometrist must be very proud!

[Keatah]

The short version:

 

The CRT look and the mechanics of how it works is important because designers of the day often considered and used the CRT's features and imperfections to their advantage for effects.

[Schizophretard]

Yes, gravity does influence the path of a beam of light. In fact, Einstein's Theory of Relativity was proven based on observations of a solar eclipse event in Australia. Photographic plates were exposed during the total eclipse event and the relative positions of the stars in close proximity to the sun were measured. These were compared to plates taken of this same region of the sky six months apart. The position of the stars measurably shifted due to the sun's massive gravity, thus relativity was proven. When an object gains enough mass that the escape velocity is more than the speed of light, it becomes a black hole and nothing can escape from it's grasp.

But, in a sense, the beam of light is still travelling in a straight line because it isn't because gravity is "pulling" on the light beam but because gravity is the curved space around the star. In other words, even the space around the Sun where this is no starlight the space is curved and it is just where there is starlight is how we see the curvature.

[Keatah]

We see the curvature because we are outside the curvature. If we were inside the curvature, the curvature would look straight.

[+5-11under]

Well, there better be a switch on the Zimba 3000 to enable/disable accounting for gravity of the electron beam. There'll also need to be a control based on the depth of the tube, and the overall viewing distance. It's annoying when the game visuals seem to be "falling" in front of my eyes, and all the colors seem to be shifted toward red.

[veelk55]

:grin: I really honestly hope Kevtris has a good time reading our comments about electrons and gravity.

 

BTW, I just acquired my first FPGA Based system. It is a PlayStation 4 add-on that works just like the Sega CD with the Genesis. You connect it to one of the USB ports on the PS4, and it can load real NES cartridges!

This is the first time Sony's and Nintendo's official games come together. Also the add-on needs its own video/audio output through a separate HDMI since the USB is too weak to transfer image and sound, but it IS enough to power the device on and produce said image/sound. This is similar to the 32X I think, I never had one, but I think it needs its own power and video cable.

The NES cartridges play absolutely lagless and nice

Also, the device is called AVS NES

[Andromeda Stardust]

:grin: I really honestly hope Kevtris has a good time reading our comments about electrons and gravity.

 

BTW, I just acquired my first FPGA Based system. It is a PlayStation 4 add-on that works just like the Sega CD with the Genesis. You connect it to one of the USB ports on the PS4, and it can load real NES cartridges!

This is the first time Sony's and Nintendo's official games come together. Also the add-on needs its own video/audio output through a separate HDMI since the USB is too weak to transfer image and sound, but it IS enough to power the device on and produce said image/sound. This is similar to the 32X I think, I never had one, but I think it needs its own power and video cable.

The NES cartridges play absolutely lagless and nice

Also, the device is called AVS NES

No PS4 required, I presume? Because I also preordered one and if I find out I need an expensive Sony product to play it, I'll be upset! Just any old USB wall wart laying around will do! :girn:

[decimata]

No PS4 required for the AVS, it plugs right into the wall. It's a really great system I've been using it most of the week now. If gets me more excited to see what Z3K can do. Because I've played emulators before and they don't run / look as good as this system handles them.

 

Id love to have all the systems.... one day with the Z3K I'd imagine.

[veelk55]

Hahahaha it was only a joke, I'm sorry. It's just in my case, the most comfortable setup I could have for it was to connect it to my PS4's USB cause I wasnt gonna disconnect other stuff from the wall. Sorry!

[Gentlegamer]

I just got an add on that plugs into my Toshiba laptop and can play NES carts! It's amazing!

[Schizophretard]

We see the curvature because we are outside the curvature. If we were inside the curvature, the curvature would look straight.

 

The curves that bends light around the Sun are the same curves that makes the Earth revolve around the Sun.

 

[phoenixdownita]

My question about the electrons was more to ask where do they go after they hit the phosphors and force it to emit a few photons?

The phosphors do not get to keep a few extra electrons so they must go somewhere, afaik there's no closing "wire" so to speak, so they have to bounce and get captured somewhere on their trip to higher voltage (remember they are electrons they go towards the + as they are charged -).

 

EDIT: not so obvious answer:

https://www.physicsforums.com/threads/where-do-electrons-go.420409/

http://physics.stackexchange.com/questions/11386/electrons-in-crt

http://cr4.globalspec.com/thread/5368/Where-Do-the-Electrons-Go

https://en.wikipedia.org/wiki/Aquadag <----- "The aquadag coating has two functions: it maintains a uniform electric field inside the tube near the screen, so the electron beam remains collimated and is not distorted by external fields, and it collects the electrons after they have hit the screen, serving as the return path for the cathode current"

[Keatah]

The curves that bends light around the Sun are the same curves that makes the Earth revolve around the Sun.

 

They are the same in that they're curves. But each one is different depending on your location.

 

The curve or path we follow may be from the same gravitational field, but the angle of entrance of the light is different (over there) and therefore experiences a different shape (relative) to us. So we see it differently.

 

When I said "outside" the curvature I meant outside and away from the location where the incoming light was being bent.

Edited September 18, 2016 by Keatah

[kevtris]

Yeah it was interesting reading about the CRT stuff! I wasn't really planning on any "crt emulation" since doing that on the FPGA can be... tough. but I was hoping to do a convincing vector monitor simulation for vectrex and the vector arcade machines (which I really want to play). I have most of how it would work figured out I think. vector simulation seems to be a fairly tough thing to get right, especially if you want to simulate things like the beam bumping off the inside walls of the CRT!

[Keatah]

I also think it's important to keep perspective and not go gung-ho all out capturing every nuance of a CRT. Not every artifact and quirk of a CRT is desirable, then or now.

 

Thing with CRT and bloom/bleed is that it is a little more than just rounding the pixels and blurring/softening of the image. The CRT is ADDING something, some extra light to the intended image it projects. Pretty much all emulators get this concept wrong. They think bilinear filtering and smoothing and all that is a good thing. It isn't - because the algorithms are taking existing pixel light and smearing it, thus resulting in a bigger but darker image.

 

CRT doesn't do that. The intended pixel lights up fully, and extra light spills over onto adjacent pixels. It's like with the dimming scanline effect - god does that suck or what?

[phoenixdownita]

Yeah it was interesting reading about the CRT stuff! I wasn't really planning on any "crt emulation" since doing that on the FPGA can be... tough. but I was hoping to do a convincing vector monitor simulation for vectrex and the vector arcade machines (which I really want to play).

Make sure that if you simulate the Vectrex you allow the same luminosity cheat, in Mine Storm you can see the invisible mines by cranking up the luminosity (it also shows the "curved" order of rendering)

 

I have most of how it would work figured out I think. vector simulation seems to be a fairly tough thing to get right, especially if you want to simulate things like the beam bumping off the inside walls of the CRT!

Is there any game that uses the "bouncing beam" technique? (without harming the players that is)

If the bell part of the CRT is conductive (aquadag or whatever they coat it with) nothing bounces really.

[cheater]

Been watching this:

 

 

why the hell is it "panel bus driver" and not "Otto"?