Post-Processing, Grain PP effect and Palette Color
A post-processing w/ grain pp effect and color palette like Buckshot.
Made for Godot 3.5 (With adjustments it is possible to apply in version 4).
Palette: Use a “GradientTexture2D” if you want.
Shader code
shader_type canvas_item;
uniform float pixel = 1.0;
uniform sampler2D pallete;
const float bit = 6.0;
const mat4 bayer = mat4(
vec4(1.0, 9.0, 3.0, 11.0),
vec4(13.0, 5.0, 15.0, 7.0),
vec4(4.0, 12.0, 2.0, 10.0),
vec4(16.0, 8.0, 14.0, 6.0));
float getbayer(int x, int y) {
if (x == 0) {
if (y == 0) return bayer[0][0];
if (y == 1) return bayer[0][1];
if (y == 2) return bayer[0][2];
if (y == 3) return bayer[0][3];
}
else if (x == 1) {
if (y == 0) return bayer[1][0];
if (y == 1) return bayer[1][1];
if (y == 2) return bayer[1][2];
if (y == 3) return bayer[1][3];
}
else if (x == 2) {
if (y == 0) return bayer[2][0];
if (y == 1) return bayer[2][1];
if (y == 2) return bayer[2][2];
if (y == 3) return bayer[2][3];
}
else if (x == 3) {
if (y == 0) return bayer[3][0];
if (y == 1) return bayer[3][1];
if (y == 2) return bayer[3][2];
if (y == 3) return bayer[3][3];
}
}
void fragment() {
vec4 original = texture(TEXTURE, UV);
vec4 _color = texture(SCREEN_TEXTURE, floor(FRAGCOORD.xy / pixel) / floor((1.0 / SCREEN_PIXEL_SIZE) / pixel));
vec4 color = _color * texture(pallete, vec2(_color.r, 1.0));
float b = getbayer(int(FRAGCOORD.x) % 4, int(FRAGCOORD.y) % 4);// * 1.0) / 1.0;
vec2 uv = FRAGCOORD.xy / SCREEN_PIXEL_SIZE;
vec4 col_noise = color;
vec3 noise = vec3(fract(sin(dot(FRAGCOORD.xy / SCREEN_PIXEL_SIZE, vec2(12.9898, 78.233))) * 43758.5453));
noise *= 0.1;
noise.xy *= (b / 16.0) * 1.5;
col_noise.rgb += noise; //noise effect
vec4 post = col_noise * floor(col_noise * 4.0) / 4.0; //noise + post-effect
COLOR *= post;
}
dude, you can just write
float getbayer(int x, int y)
{
return bayer[x][y];
}
I had already tried to simplify this function, but Godot in its older versions, such as GLES2, does not allow this way of searching for an index in an array. The error it returns is this: “Only integer constants are allowed as index at the moment”.
Thanks for the help in any way!
unfortunately i can’t seem to make it work with godot 4.2 🙁
does anyone managed to do it ?
Similarly to what @anusb already said I can compile it in Godot 4.2.1 but I cannot make it work.
Premise: the game I am trying this with is dark (few and not intense light sources) and I am an absolute beginner in shaders.
This is what I have done…
in the player’s 1st person view, create a ColorRect leaving the color “white” as defaultin “Material” I have set “ShaderMaterial”in the Shader Editor I have pasted your code but I have added, as suggested by the editor, this line of code in the definitions sectionuniform sampler2D SCREEN_TEXTURE: hint_screen_texture, filter_linear_mipmap;
in the Shaders Parameters, Pixel is 1 and Pallete is the default black-to-white “GradientTexture2D”Result: it compiles and run but it’s all black, I cannot see anything.
Variant: if I clear the Pallete section and I leave it blank it’s still extremely dark and unplayable, but I can sort of see the sky outline, so it might be an improvement.
I feel I might be missing something, but please let me know if you have any suggestions.
I’m trying to get it to work If i find it out I’ll let you know.