(GZDoom) Monochrome global shader

[ZZYZX]

This is a PK3 that will make your Doom black and white.
So basically few days ago I saw Zeberpal's monochrome software pyramid WAD and wanted to reproduce that effect with GLSL.
I couldn't reproduce exactly that effect (for that, see InsanityBringer's post), but made something good enough to put it as a separate mod in a separate thread.
Note that for this to work, relatively recent version of GZDoom is required (tested on pre-r1729).

Screenshot: http://i.imgur.com/tCSLOJL.png
Download: http://www.mediafire.com/download/skjy2 ... chrome.pk3
Bonus screenshot (tied this shader to subtractive lights): http://i.imgur.com/361mFsV.png
Bonus download: http://www.mediafire.com/download/dukto ... ective.pk3

Code is free to use anywhere, whatever.
Also see my other shader tinkering here.

Known bugs: the weapon is not monochrome because of the way I'm detecting HUD (since the HUD shouldn't be monochrome).

[ibm5155]

Hey, ZZYZX, since you're more into this glsl area, do you know if it's hard to make a proper flash light using the shaders? I already tried once and it almost worked well, the only problem were there missing values alike the gamera angle and pitch.
Do you belive it's hard to send those values into the glsl shaders? (plus some bool flag for enable/disable the flashlight )

[Nash]

Directional spotlights should be added into GZDoom as a stock feature IMO.

[ZZYZX]

the only problem were there missing values alike the gamera angle and pitch.

I think angle and pitch is ViewMatrix in world coordinates. Not 100% sure though.

Code: Select all

void FGLRenderer::SetViewMatrix(fixed_t viewx, fixed_t viewy, fixed_t viewz, bool mirror, bool planemirror)
{
	float mult = mirror? -1:1;
	float planemult = planemirror? -glset.pixelstretch : glset.pixelstretch;

	gl_RenderState.mViewMatrix.loadIdentity();
	gl_RenderState.mViewMatrix.rotate(GLRenderer->mAngles.Roll,  0.0f, 0.0f, 1.0f);
	gl_RenderState.mViewMatrix.rotate(GLRenderer->mAngles.Pitch, 1.0f, 0.0f, 0.0f);
	gl_RenderState.mViewMatrix.rotate(GLRenderer->mAngles.Yaw,   0.0f, mult, 0.0f);
	gl_RenderState.mViewMatrix.translate(FIXED2FLOAT(viewx) * mult, -FIXED2FLOAT(viewz) * planemult , -FIXED2FLOAT(viewy));
	gl_RenderState.mViewMatrix.scale(-mult, planemult, 1);
}

But I don't think you even need that, for simple flashlight it's enough to work in screen space using gl_FragCoord or something like I made in my mod (because for whatever reason gl_FragCoord wasnt working for me... wat)
Turning shader effects on and off is not possible though. Maybe if you could check if camera has nonzero roll... but then again, this information is only stored in a matrix and I don't think there's a way to check if roll is 0 in an already computed matrix.

Also technically you can send a bool variable but you will need to modify GZDoom itself. Scene uniforms are stored and set in gl_RenderState.

[Zeberpal]

ZZYZX,

Let's say I have an acid green color(#00FF00 aka 0,255,0), and I wish it to get chromokeyed with your shader effect. But just this concrete color shade. Exclude all the other shades of green palette. Everything that has this color - textures, sprites, models even is affected by shader. Is it possible in theory?

[ZZYZX]

So basically things that have **FE** aren't affected, but **FF** are? Yes, this is perfectly possible and even better than with dynamic lights. Since dynamic lights won't work on actors and hence my "partial" shader version is bad and doesn't work on actors really.

Actually, I just realized that you can tie the shader to desaturation factor, and then actors are affected flawlessly, even though dynamic lights (for this effect) won't be supported.
I also fixed the shader so that it no more requires replacing main.vp and also supports recoloring of player's weapon.

http://www.mediafire.com/download/vb74x ... eDesat.pk3

[Zeberpal]

wow, that's neat effect! It's green dynlights that desature the wall, am I right?

[ZZYZX]

No. It's not dynlights at all. It's UDMF desaturation factor put on the sector.

[Zeberpal]

ZZYZX, this is stunning %)