fleeting-garden/src/pipelines/agents/agent.wgsl

119 lines
3.6 KiB
WebGPU Shading Language

struct Agent {
position: vec2<f32>,
angle: f32,
species: f32,
timeToLive: f32
}
struct Settings {
size: vec2<f32>,
deltaTime: f32,
time: f32,
trailWeight: f32,
moveRate: f32,
turnRate: f32,
sensorAngle: f32,
sensorOffset: f32,
};
@group(0) @binding(0) var<uniform> settings: Settings;
@group(0) @binding(1) var<storage, read_write> agents: array<Agent>;
@group(0) @binding(2) var TrailMapIn: texture_2d<f32>;
@group(0) @binding(3) var TrailMapOut: texture_storage_2d<rgba16float, write>;
@compute @workgroup_size(8, 8)
fn main(@builtin(global_invocation_id) global_id: vec3<u32>) {
let id = global_id.x;
if (id >= arrayLength(&agents)) {
return;
}
var agent = agents[id];
if (agent.timeToLive <= 0.) {
agent.position = vec2(random(id + u32(settings.time * 10 + agent.position.x * 10000)),
random(id + u32(settings.time * 10 + agent.position.y * 10000)));
agent.angle = random(id + u32(settings.time)) * 3.14159265359 * 2.;
agent.species = 1;
agent.timeToLive = 1000;
agents[id] = agent;
return;
}
let random = random(id + u32(settings.time * 10000 + agent.position.y * 10 + agent.position.x));
let trailCurrent = sense(agent, 0, 0);
var weight: f32;
if(agent.species == 0) {
weight = trailCurrent.r - trailCurrent.g;
} else {
weight = trailCurrent.g - trailCurrent.r;
}
if (weight < 0) {
agent.timeToLive = 0;
return;
}
let trailForward = sense(agent, settings.sensorOffset, 0);
let trailLeft = sense(agent, settings.sensorOffset, settings.sensorAngle);
let trailRight = sense(agent, settings.sensorOffset, -settings.sensorAngle);
var weightForward: f32 = trailForward.a;
var weightLeft: f32 = trailLeft.a;
var weightRight: f32 = trailRight.a;
if (agent.species == 0) {
weightForward += trailForward.r - trailForward.g;
weightLeft += trailLeft.r - trailLeft.g;
weightRight += trailRight.r - trailRight.g;
} else {
weightForward += trailForward.g - trailForward.r;
weightLeft += trailLeft.g - trailLeft.r;
weightRight += trailRight.g - trailRight.r;
}
if (weightForward < weightLeft && weightForward < weightRight) {
agent.angle += (random - 0.5) * 2. * settings.turnRate;
} else if (weightLeft < weightRight) {
agent.angle -= random * settings.turnRate;
} else if (weightRight < weightLeft) {
agent.angle += random * settings.turnRate;
}
let direction = vec2(cos(agent.angle), sin(agent.angle));
var newPos = agent.position + direction / normalize(settings.size) * settings.moveRate;
newPos = clamp(newPos, vec2<f32>(0, 0), vec2<f32>(1, 1));
if (newPos.x == 0. || newPos.x == 1. || newPos.y == 0. || newPos.y == 1.) {
agent.angle += 3.14159265359 + random - 0.5;
}
var trail = vec4<f32>(0, 1, 0, 0);
if (agent.species == 0) {
trail = vec4(1, 0, 0, 0);
}
textureStore(TrailMapOut, vec2<i32>(newPos * settings.size), trail);
agent.position = newPos;
agent.timeToLive -= settings.deltaTime;
agents[id] = agent;
}
fn sense(agent: Agent, sensorOffset: f32, sensorOffsetAngle: f32) -> vec4<f32> {
let sensorAngle = agent.angle + sensorOffsetAngle;
let sensorDir: vec2<f32> = vec2(cos(sensorAngle), sin(sensorAngle)) / normalize(settings.size);
let sensorPos: vec2<f32> = agent.position + sensorDir * sensorOffset;
return textureLoad(TrailMapIn, vec2<i32>(sensorPos * settings.size), 0);
}
fn random(state0: u32) -> f32 {
var state: u32 = state0;
state = state ^ 2747636419u;
state = state * 2654435769u;
state = state ^ (state >> 16u);
state = state * 2654435769u;
state = state ^ (state >> 16u);
state = state * 2654435769u;
return f32(state) / 4294967295.0;
}