stk-code_catmod/data/shaders/fog.frag

uniform sampler2D tex;

uniform float fogmax;
uniform float startH;
uniform float endH;
uniform float start;
uniform float end;
uniform vec3 col;

out vec4 FragColor;


vec4 getPosFromUVDepth(vec3 uvDepth, mat4 InverseProjectionMatrix);

void main()
{
    vec2 uv = gl_FragCoord.xy / screen;
    float z = texture(tex, uv).x;
    vec4 xpos = getPosFromUVDepth(vec3(uv, z), InverseProjectionMatrix);

    float dist = length(xpos.xyz);
    vec3 fog = col * (1. - exp(- fogmax * .01 * dist));

    FragColor = vec4(fog, 1.);
}