theShade.glsl

#version 150


// All of the uniform variables are declared in the side control panel
uniform float time;
uniform vec2 resolution;

uniform sampler2D texture0; 
uniform sampler2D prevFrame;

// this is part of the pipeline, it doenst really concern us.
in VertexData
{
    vec4 v_position;
    vec3 v_normal;
    vec2 v_texcoord;
} inData;

out vec4 nodeStatus; // this is what the output of the node will be

void main(void)
{
    vec2 nodeID = inData.v_texcoord;
    // this ^^^^ is all the information we have about our fog node. 
    //JUST the ID which correleates to a pixel position on screen
    // so the node given the ID (0,0) is in the bottom left screen and 
    // the node with the ID (1,1) is represetnted by the pixel in the top right

    vec4 prevNodeStatus = texture(prevFrame, nodeID); // if this line isnt working, you have
    //a different version of kodelife change the function texture to be texture2D
    
    float frequency = 0.2;
    
    vec2 i = nodeID*8.0- vec2(20.0); // these are magic numbers that scale it to fit the screen

    float intensity = .2;
  
    float t = time;
    
    //these next two lines are where the magic happens! feel free to noodle around with the numbers
    i += vec2(cos(t - i.x) + sin(t + i.y), sin(t - i.y) + cos(t + i.x));
    float fog = 2.0+ (8/length(vec2(i.x / (sin(i.x+t)/intensity),i.y / (cos(i.y+t)/intensity))));
    
    //normalizes the (intensity)colors so theyre between 0 and 1
    fog = 1.0-sqrt(fog);
    fog = fog*fog*fog*fog;

    // if the fog is too bright, copy what it was the previous moment(frame)
    if (fog > 0.3){
        fog = prevNodeStatus.x * 0.99;
    }

    vec4 final = vec4(vec3(fog), 1.0); // casting to a vec4
    //ignore the last number it doesnt matter in this context
    
    nodeStatus = final;
}