precision highp float;
precision highp int;

in vec2 vUv;

out vec4 FragColor;

uniform sampler2D tLastState;
uniform sampler2D tDiscreteAnts;

void main()	{
    vec4 lastState = texture(tLastState, vUv);
    vec4 discreteAnts = texture(tDiscreteAnts, vUv);

    float materialId = lastState.x;
    float scentToHome = min(SCENT_MAX_PER_CELL, lastState.y + discreteAnts.x);
    float scentToFood = min(SCENT_MAX_PER_CELL, lastState.z + discreteAnts.y);
    float repellent = min(REPELLENT_MAX_PER_CELL, lastState.w);

    // ant picked up food from this cell
    if (discreteAnts.z == 1.) {
        materialId = float(MAT_AIR);
    }

    FragColor = vec4(materialId, scentToHome, scentToFood, repellent);
}