CRT/Retro Emulation

[Disthron]

Hay everyone, I'm trying to use this shader for my game Edelin Tales: Portals of Doom but I can't seem to get it to work properly.

I keep getting these really nasty looking bulging bands across the screen. Example screenshot below. Anyone have any idea what might be causing this, or how I might fix it? What's shown in the picture is the shader with all atributes on default. But I've tried playing around with the settings and I can't seem to get those bands to go away. Any help would be appreciated.

[mobichan]

Hahaha. That is what a CRT monitor does, but only when it gets old an messy. Try adjusting the parameters. Distortion is what is bending the image, so you can set it to 0 (or a very low number like 0.001). Input/Output Gamma affect the way it blends to your image colors. Input/Output Width and Height affect the thickness of the lines. You can also try the horizontal version I uploaded to the thread. It makes more sense if your game screen is wider than tall.

[Disthron]

@Mobichan: Dude! I have actual 3 CRT TVs in my house (I'm not wasting money on a new TV when my old ones work just fine!) and nun of them look like that. Not even the oldest one I inherited from my grandma!

I think I tried the horizontal one and it gave me the same effect. So, I'm still confused about the hight/width input/output. How dose it effect the thickness of the lines? All it seemed to do was make the bulge and distortion go off to one side.

Anyway, thanks for getting back to me so quickly.

[mobichan]

I was talking about CRT monitors (like in arcade cabinets). I have 2 cabinets and they both show the wear of many years of use. But either way, the shader settings are there to display the good and the bad of CRT's. Now that I play more with them, the distortion settings actually look subtle when you run the game with "Resize display to fill window" checked. Kind of unfortunate that just running the frame in a window doesn't get the same results. The thickness change only seems to be in window mode, but I guess it is changing the sharpness of the lines. So if you set both "inputs" to 2 and "outputs" to 1, you can see that the scanlines appear thicker.

In general, this isn't going to give the results of say, MAME with a scanline overlay. But it does a great job of making it feel like a CRT.

EDIT: The settings I found pleasing to me were:

Effect: CRT Hori
Phase: 0
Input Gamma: 5.0
Output Gamma: 5.0
Distortion: 0.005 (make it 0 if you want a "brand new" monitor feel)
Input Width: 1.0
Input Height: 1.0
Output Width: 1.0
Output Height: 1.0
Blend Coefficient: 0 (can't seem to make this do anything)
RGB Coefficient: 255, 255, 255

[Disthron]

@Snail: What I'm trying to do is get rid of those.... black bands that bulge in the centrer of the screen. I've never seen that on an actual CRT, not even in the arcade. In the picture the big red arrow points to it.

I've discovered that if you set the distortion to 0.00 it will get rid of those lines but the distortion is part of the CRT effect. It would also be good if I could make the scan lines a bit bigger. Since the graphics are 2x to begin with.

@Mobichan: I think those lines should be there but they should be a subtle gradient rather than a glaring black line. I'm pretty sure if they were that bad the technology wouldn't have been used.

Hmm... maybe if I distorted the screen with the lens object or something and then used the CRT shader with no distortion applied? Any idea what a lens picture would look like that would make that kind of distortion? Because it's a pretty subtle curve, or at least I fee it should be.

[mobichan]

Maybe post a screen of the effect you are trying to achieve? The distortion needs some pretty tiny adjustments to keep it from getting out of control. I suggested 0.005 and that makes the corners feels a bit of distortion but leaves the center clean. As for the x2 scaling, that is just a limitation of the shader, I think. Maybe try it with Ultimate Walruses fullscreen object and drop your assets back to x1 rez?

[Disthron]

Something like the pictures bellow. If you look really close you can see they still have those overlaying bands but they are very subtle. The distortion is a bit more pronounced but not so extreme that the image appears totally warped.

[mobichan]

Here is what I meant before. There seems to be a bug where it looks extreme when running in a window. But if you set the project display properties (under Options section) to use "Keep Screen Ratio" and "Resize display to Fill window size" you get the larger image below. It is much more subtle and probably what is the intended output of the shader. This is using the default settings as well.



EDIT: Sorry the attachments are getting reduced and turned to jpg. T_T

EDIT2: Just added Ultimate Fullscreen to my game and it works pretty well with that. The only real issue is that using integer scaling, there is a deadzone around my frame/window. Objects there are stretched really badly from the distortion of the shader. :/

[Disthron]

Ok, for this test I set the distortion to 0.000 and instead used an active with the lens shader on it to distort the picture. What do you think?

[nivram]

That is really good.

Marv