Naloga 3 WIP

2024-12-28 19:58:17 +01:00
parent 7ad330422b
commit a20a45ebd0
51 changed files with 3327 additions and 28 deletions
--- a/naloga_3/engine/WebGPU.js
+++ b/naloga_3/engine/WebGPU.js
@@ -0,0 +1,73 @@
+export function createBuffer(device, { data, usage }) {
+    const buffer = device.createBuffer({
+        size: Math.ceil(data.byteLength / 4) * 4,
+        mappedAtCreation: true,
+        usage,
+    });
+    if (ArrayBuffer.isView(data)) {
+        new data.constructor(buffer.getMappedRange()).set(data);
+    } else {
+        new Uint8Array(buffer.getMappedRange()).set(new Uint8Array(data));
+    }
+    buffer.unmap();
+    return buffer;
+}
+
+export function createTextureFromSource(device, {
+    source,
+    format = 'rgba8unorm',
+    usage = 0,
+    mipLevelCount = 1,
+    flipY = false,
+}) {
+    const size = [source.width, source.height];
+    const texture = device.createTexture({
+        format,
+        size,
+        mipLevelCount,
+        usage: usage |
+            GPUTextureUsage.TEXTURE_BINDING |
+            GPUTextureUsage.COPY_DST |
+            GPUTextureUsage.RENDER_ATTACHMENT,
+    });
+    device.queue.copyExternalImageToTexture(
+        { source, flipY },
+        { texture },
+        size,
+    );
+    return texture;
+}
+
+export function createTextureFromData(device, {
+    data,
+    size,
+    bytesPerRow,
+    rowsPerImage,
+    format = 'rgba8unorm',
+    dimension = '2d',
+    usage = 0,
+    mipLevelCount = 1,
+    flipY = false,
+}) {
+    const texture = device.createTexture({
+        format,
+        size,
+        mipLevelCount,
+        usage: usage | GPUTextureUsage.COPY_DST,
+    });
+    device.queue.writeTexture(
+        { texture },
+        data,
+        { bytesPerRow, rowsPerImage },
+        size,
+    );
+    return texture;
+}
+
+export function createTexture(device, options) {
+    if (options.source) {
+        return createTextureFromSource(device, options);
+    } else {
+        return createTextureFromData(device, options);
+    }
+}
--- a/naloga_3/engine/animators/EasingFunctions.js
+++ b/naloga_3/engine/animators/EasingFunctions.js
@@ -0,0 +1,47 @@
+export function swap(f, t, ...args) { return 1 - f(1 - t, ...args); }
+export function inout(f, t, ...args) { return t < 0.5 ? f(2 * t, ...args) / 2 : 1 - f(2 * (1 - t), ...args) / 2; }
+
+export function step(t, p = 0) { return t < p ? 0 : 1; }
+export function stepEaseIn(...args) { return step(...args); }
+export function stepEaseOut(...args) { return swap(step, ...args); }
+export function stepEaseInOut(...args) { return inout(step, ...args); }
+
+export function linear(t) { return t; }
+export function linearEaseIn(...args) { return linear(...args); }
+export function linearEaseOut(...args) { return swap(linear, ...args); }
+export function linearEaseInOut(...args) { return inout(linear, ...args); }
+
+export function poly(t, p = 2) { return Math.pow(t, p); }
+export function polyEaseIn(...args) { return poly(...args); }
+export function polyEaseOut(...args) { return swap(poly, ...args); }
+export function polyEaseInOut(...args) { return inout(poly, ...args); }
+
+export function expo(t, p = 5) { return (Math.exp(p * t) - 1) / (Math.exp(p) - 1); }
+export function expoEaseIn(...args) { return expo(...args); }
+export function expoEaseOut(...args) { return swap(expo, ...args); }
+export function expoEaseInOut(...args) { return inout(expo, ...args); }
+
+export function sine(t, n = 1) { return 1 - Math.cos(n * t * Math.PI / 2); }
+export function sineEaseIn(...args) { return sine(...args); }
+export function sineEaseOut(...args) { return swap(sine, ...args); }
+export function sineEaseInOut(...args) { return inout(sine, ...args); }
+
+export function circ(t) { return 1 - Math.sqrt(1 - t * t); }
+export function circEaseIn(...args) { return circ(...args); }
+export function circEaseOut(...args) { return swap(circ, ...args); }
+export function circEaseInOut(...args) { return inout(circ, ...args); }
+
+export function back(t, p = 2) { return t * t * ((p + 1) * t - p); }
+export function backEaseIn(...args) { return back(...args); }
+export function backEaseOut(...args) { return swap(back, ...args); }
+export function backEaseInOut(...args) { return inout(back, ...args); }
+
+export function elastic(t, p = 5, n = 5) { return expo(t, p) * (1 - sine(t, 4 * n)); }
+export function elasticEaseIn(...args) { return elastic(...args); }
+export function elasticEaseOut(...args) { return swap(elastic, ...args); }
+export function elasticEaseInOut(...args) { return inout(elastic, ...args); }
+
+export function bounce(t, p = 2, n = 2) { return Math.abs(poly(t, p) * (1 - sine(t, 4 * n))); }
+export function bounceEaseIn(...args) { return bounce(...args); }
+export function bounceEaseOut(...args) { return swap(bounce, ...args); }
+export function bounceEaseInOut(...args) { return inout(bounce, ...args); }
--- a/naloga_3/engine/animators/LinearAnimator.js
+++ b/naloga_3/engine/animators/LinearAnimator.js
@@ -0,0 +1,54 @@
+import { vec3 } from 'glm';
+
+import { Transform } from '../core/Transform.js';
+
+export class LinearAnimator {
+
+    constructor(node, {
+        startPosition = [0, 0, 0],
+        endPosition = [0, 0, 0],
+        startTime = 0,
+        duration = 1,
+        loop = false,
+    } = {}) {
+        this.node = node;
+
+        this.startPosition = startPosition;
+        this.endPosition = endPosition;
+
+        this.startTime = startTime;
+        this.duration = duration;
+        this.loop = loop;
+
+        this.playing = true;
+    }
+
+    play() {
+        this.playing = true;
+    }
+
+    pause() {
+        this.playing = false;
+    }
+
+    update(t, dt) {
+        if (!this.playing) {
+            return;
+        }
+
+        const linearInterpolation = (t - this.startTime) / this.duration;
+        const clampedInterpolation = Math.min(Math.max(linearInterpolation, 0), 1);
+        const loopedInterpolation = ((linearInterpolation % 1) + 1) % 1;
+        this.updateNode(this.loop ? loopedInterpolation : clampedInterpolation);
+    }
+
+    updateNode(interpolation) {
+        const transform = this.node.getComponentOfType(Transform);
+        if (!transform) {
+            return;
+        }
+
+        vec3.lerp(transform.translation, this.startPosition, this.endPosition, interpolation);
+    }
+
+}
--- a/naloga_3/engine/animators/RotateAnimator.js
+++ b/naloga_3/engine/animators/RotateAnimator.js
@@ -0,0 +1,54 @@
+import { quat, vec3 } from 'glm';
+
+import { Transform } from '../core/Transform.js';
+
+export class RotateAnimator {
+
+    constructor(node, {
+        startRotation = [0, 0, 0, 1],
+        endRotation = [0, 0, 0, 1],
+        startTime = 0,
+        duration = 1,
+        loop = false,
+    } = {}) {
+        this.node = node;
+
+        this.startRotation = startRotation;
+        this.endRotation = endRotation;
+
+        this.startTime = startTime;
+        this.duration = duration;
+        this.loop = loop;
+
+        this.playing = true;
+    }
+
+    play() {
+        this.playing = true;
+    }
+
+    pause() {
+        this.playing = false;
+    }
+
+    update(t, dt) {
+        if (!this.playing) {
+            return;
+        }
+
+        const linearInterpolation = (t - this.startTime) / this.duration;
+        const clampedInterpolation = Math.min(Math.max(linearInterpolation, 0), 1);
+        const loopedInterpolation = ((linearInterpolation % 1) + 1) % 1;
+        this.updateNode(this.loop ? loopedInterpolation : clampedInterpolation);
+    }
+
+    updateNode(interpolation) {
+        const transform = this.node.getComponentOfType(Transform);
+        if (!transform) {
+            return;
+        }
+
+        quat.slerp(transform.rotation, this.startRotation, this.endRotation, interpolation);
+    }
+
+}
--- a/naloga_3/engine/controllers/FirstPersonController.js
+++ b/naloga_3/engine/controllers/FirstPersonController.js
@@ -0,0 +1,131 @@
+import { quat, vec3, mat4 } from 'glm';
+
+import { Transform } from '../core/Transform.js';
+
+export class FirstPersonController {
+
+    constructor(node, domElement, {
+        pitch = 0,
+        yaw = 0,
+        velocity = [0, 0, 0],
+        acceleration = 50,
+        maxSpeed = 5,
+        decay = 0.99999,
+        pointerSensitivity = 0.002,
+    } = {}) {
+        this.node = node;
+        this.domElement = domElement;
+
+        this.keys = {};
+
+        this.pitch = pitch;
+        this.yaw = yaw;
+
+        this.velocity = velocity;
+        this.acceleration = acceleration;
+        this.maxSpeed = maxSpeed;
+        this.decay = decay;
+        this.pointerSensitivity = pointerSensitivity;
+
+        this.initHandlers();
+    }
+
+    initHandlers() {
+        this.pointermoveHandler = this.pointermoveHandler.bind(this);
+        this.keydownHandler = this.keydownHandler.bind(this);
+        this.keyupHandler = this.keyupHandler.bind(this);
+
+        const element = this.domElement;
+        const doc = element.ownerDocument;
+
+        doc.addEventListener('keydown', this.keydownHandler);
+        doc.addEventListener('keyup', this.keyupHandler);
+
+        element.addEventListener('click', e => element.requestPointerLock());
+        doc.addEventListener('pointerlockchange', e => {
+            if (doc.pointerLockElement === element) {
+                doc.addEventListener('pointermove', this.pointermoveHandler);
+            } else {
+                doc.removeEventListener('pointermove', this.pointermoveHandler);
+            }
+        });
+    }
+
+    update(t, dt) {
+        // Calculate forward and right vectors.
+        const cos = Math.cos(this.yaw);
+        const sin = Math.sin(this.yaw);
+        const forward = [-sin, 0, -cos];
+        const right = [cos, 0, -sin];
+
+        // Map user input to the acceleration vector.
+        const acc = vec3.create();
+        if (this.keys['KeyW']) {
+            vec3.add(acc, acc, forward);
+        }
+        if (this.keys['KeyS']) {
+            vec3.sub(acc, acc, forward);
+        }
+        if (this.keys['KeyD']) {
+            vec3.add(acc, acc, right);
+        }
+        if (this.keys['KeyA']) {
+            vec3.sub(acc, acc, right);
+        }
+
+        // Update velocity based on acceleration.
+        vec3.scaleAndAdd(this.velocity, this.velocity, acc, dt * this.acceleration);
+
+        // If there is no user input, apply decay.
+        if (!this.keys['KeyW'] &&
+            !this.keys['KeyS'] &&
+            !this.keys['KeyD'] &&
+            !this.keys['KeyA'])
+        {
+            const decay = Math.exp(dt * Math.log(1 - this.decay));
+            vec3.scale(this.velocity, this.velocity, decay);
+        }
+
+        // Limit speed to prevent accelerating to infinity and beyond.
+        const speed = vec3.length(this.velocity);
+        if (speed > this.maxSpeed) {
+            vec3.scale(this.velocity, this.velocity, this.maxSpeed / speed);
+        }
+
+        const transform = this.node.getComponentOfType(Transform);
+        if (transform) {
+            // Update translation based on velocity.
+            vec3.scaleAndAdd(transform.translation,
+                transform.translation, this.velocity, dt);
+
+            // Update rotation based on the Euler angles.
+            const rotation = quat.create();
+            quat.rotateY(rotation, rotation, this.yaw);
+            quat.rotateX(rotation, rotation, this.pitch);
+            transform.rotation = rotation;
+        }
+    }
+
+    pointermoveHandler(e) {
+        const dx = e.movementX;
+        const dy = e.movementY;
+
+        this.pitch -= dy * this.pointerSensitivity;
+        this.yaw   -= dx * this.pointerSensitivity;
+
+        const twopi = Math.PI * 2;
+        const halfpi = Math.PI / 2;
+
+        this.pitch = Math.min(Math.max(this.pitch, -halfpi), halfpi);
+        this.yaw = ((this.yaw % twopi) + twopi) % twopi;
+    }
+
+    keydownHandler(e) {
+        this.keys[e.code] = true;
+    }
+
+    keyupHandler(e) {
+        this.keys[e.code] = false;
+    }
+
+}
--- a/naloga_3/engine/controllers/OrbitController.js
+++ b/naloga_3/engine/controllers/OrbitController.js
@@ -0,0 +1,74 @@
+import { quat, vec3 } from 'glm';
+
+import { Transform } from '../core/Transform.js';
+
+export class OrbitController {
+
+    constructor(node, domElement, {
+        rotation = [0, 0, 0, 1],
+        distance = 2,
+        moveSensitivity = 0.004,
+        zoomSensitivity = 0.002,
+    } = {}) {
+        this.node = node;
+        this.domElement = domElement;
+
+        this.rotation = rotation;
+        this.distance = distance;
+
+        this.moveSensitivity = moveSensitivity;
+        this.zoomSensitivity = zoomSensitivity;
+
+        this.initHandlers();
+    }
+
+    initHandlers() {
+        this.pointerdownHandler = this.pointerdownHandler.bind(this);
+        this.pointerupHandler = this.pointerupHandler.bind(this);
+        this.pointermoveHandler = this.pointermoveHandler.bind(this);
+        this.wheelHandler = this.wheelHandler.bind(this);
+
+        this.domElement.addEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.addEventListener('wheel', this.wheelHandler);
+    }
+
+    pointerdownHandler(e) {
+        this.domElement.setPointerCapture(e.pointerId);
+        this.domElement.requestPointerLock();
+        this.domElement.removeEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.addEventListener('pointerup', this.pointerupHandler);
+        this.domElement.addEventListener('pointermove', this.pointermoveHandler);
+    }
+
+    pointerupHandler(e) {
+        this.domElement.releasePointerCapture(e.pointerId);
+        this.domElement.ownerDocument.exitPointerLock();
+        this.domElement.addEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.removeEventListener('pointerup', this.pointerupHandler);
+        this.domElement.removeEventListener('pointermove', this.pointermoveHandler);
+    }
+
+    pointermoveHandler(e) {
+        const dx = e.movementX;
+        const dy = e.movementY;
+
+        quat.rotateX(this.rotation, this.rotation, -dy * this.moveSensitivity);
+        quat.rotateY(this.rotation, this.rotation, -dx * this.moveSensitivity);
+        quat.normalize(this.rotation, this.rotation);
+    }
+
+    wheelHandler(e) {
+        this.distance *= Math.exp(this.zoomSensitivity * e.deltaY);
+    }
+
+    update() {
+        const transform = this.node.getComponentOfType(Transform);
+        if (!transform) {
+            return;
+        }
+
+        quat.copy(transform.rotation, this.rotation);
+        vec3.transformQuat(transform.translation, [0, 0, this.distance], this.rotation);
+    }
+
+}
--- a/naloga_3/engine/controllers/TouchController.js
+++ b/naloga_3/engine/controllers/TouchController.js
@@ -0,0 +1,143 @@
+import { quat, vec2, vec3 } from 'glm';
+
+import { Transform } from 'engine/core/Transform.js';
+
+export class TouchController {
+
+    constructor(node, domElement, {
+        translation = [0, 0, 0],
+        rotation = [0, 0, 0, 1],
+        distance = 2,
+        translateSensitivity = 0.001,
+        rotateSensitivity = 0.004,
+        wheelSensitivity = 0.002,
+    } = {}) {
+        this.node = node;
+        this.domElement = domElement;
+
+        this.translation = translation;
+        this.rotation = rotation;
+        this.distance = distance;
+
+        this.translateSensitivity = translateSensitivity;
+        this.rotateSensitivity = rotateSensitivity;
+        this.wheelSensitivity = wheelSensitivity;
+
+        this.pointers = new Map();
+        this.initHandlers();
+    }
+
+    initHandlers() {
+        this.pointerdownHandler = this.pointerdownHandler.bind(this);
+        this.pointerupHandler = this.pointerupHandler.bind(this);
+        this.pointermoveHandler = this.pointermoveHandler.bind(this);
+        this.wheelHandler = this.wheelHandler.bind(this);
+
+        this.domElement.addEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.addEventListener('pointerup', this.pointerupHandler);
+        this.domElement.addEventListener('pointercancel', this.pointerupHandler);
+        this.domElement.addEventListener('pointermove', this.pointermoveHandler);
+        this.domElement.addEventListener('wheel', this.wheelHandler);
+    }
+
+    pointerdownHandler(e) {
+        this.pointers.set(e.pointerId, e);
+        this.domElement.setPointerCapture(e.pointerId);
+        this.domElement.requestPointerLock();
+    }
+
+    pointerupHandler(e) {
+        this.pointers.delete(e.pointerId);
+        this.domElement.releasePointerCapture(e.pointerId);
+        this.domElement.ownerDocument.exitPointerLock();
+    }
+
+    pointermoveHandler(e) {
+        if (!this.pointers.has(e.pointerId)) {
+            return;
+        }
+
+        if (this.pointers.size === 1) {
+            if (e.shiftKey) {
+                this.translate(e.movementX, e.movementY);
+            } else {
+                this.rotate(e.movementX, e.movementY);
+            }
+            this.pointers.set(e.pointerId, e);
+        } else {
+            const N = this.pointers.size;
+
+            // Points before movement
+            const A = [...this.pointers.values()].map(e => [e.clientX, e.clientY]);
+
+            this.pointers.set(e.pointerId, e);
+
+            // Points after movement
+            const B = [...this.pointers.values()].map(e => [e.clientX, e.clientY]);
+
+            const centroidA = A.reduce((a, v) => vec2.scaleAndAdd(a, a, v, 1 / N), [0, 0]);
+            const centroidB = B.reduce((a, v) => vec2.scaleAndAdd(a, a, v, 1 / N), [0, 0]);
+
+            const translation = vec2.subtract(vec2.create(), centroidB, centroidA);
+
+            const centeredA = A.map(v => vec2.subtract(vec2.create(), v, centroidA));
+            const centeredB = B.map(v => vec2.subtract(vec2.create(), v, centroidB));
+
+            const scaleA = centeredA.reduce((a, v) => a + vec2.length(v) / N, 0);
+            const scaleB = centeredB.reduce((a, v) => a + vec2.length(v) / N, 0);
+
+            const scale = scaleA / scaleB;
+
+            const normalizedA = centeredA.map(v => vec2.normalize(vec2.create(), v));
+            const normalizedB = centeredB.map(v => vec2.normalize(vec2.create(), v));
+
+            let sin = 0;
+            for (let i = 0; i < A.length; i++) {
+                const a = normalizedA[i];
+                const b = normalizedB[i];
+                sin += (a[0] * b[1] - a[1] * b[0]) / N;
+            }
+            const angle = Math.asin(sin);
+
+            this.translate(...translation);
+            this.scale(scale);
+            this.screw(angle);
+        }
+    }
+
+    wheelHandler(e) {
+        this.scale(Math.exp(e.deltaY * this.wheelSensitivity));
+    }
+
+    screw(amount) {
+        quat.rotateZ(this.rotation, this.rotation, amount);
+    }
+
+    rotate(dx, dy) {
+        quat.rotateX(this.rotation, this.rotation, -dy * this.rotateSensitivity);
+        quat.rotateY(this.rotation, this.rotation, -dx * this.rotateSensitivity);
+        quat.normalize(this.rotation, this.rotation);
+    }
+
+    translate(dx, dy) {
+        const translation = [-dx, dy, 0];
+        vec3.transformQuat(translation, translation, this.rotation);
+        vec3.scaleAndAdd(this.translation, this.translation, translation, this.distance * this.translateSensitivity);
+    }
+
+    scale(amount) {
+        this.distance *= amount;
+    }
+
+    update() {
+        const transform = this.node.getComponentOfType(Transform);
+        if (!transform) {
+            return;
+        }
+
+        quat.copy(transform.rotation, this.rotation);
+        vec3.transformQuat(transform.translation, [0, 0, this.distance], this.rotation);
+        vec3.add(transform.translation, transform.translation, this.translation);
+    }
+
+}
--- a/naloga_3/engine/controllers/TurntableController.js
+++ b/naloga_3/engine/controllers/TurntableController.js
@@ -0,0 +1,88 @@
+import { quat, vec3 } from 'glm';
+
+import { Transform } from '../core/Transform.js';
+
+export class TurntableController {
+
+    constructor(node, domElement, {
+        pitch = 0,
+        yaw = 0,
+        distance = 1,
+        moveSensitivity = 0.004,
+        zoomSensitivity = 0.002,
+    } = {}) {
+        this.node = node;
+        this.domElement = domElement;
+
+        this.pitch = pitch;
+        this.yaw = yaw;
+        this.distance = distance;
+
+        this.moveSensitivity = moveSensitivity;
+        this.zoomSensitivity = zoomSensitivity;
+
+        this.initHandlers();
+    }
+
+    initHandlers() {
+        this.pointerdownHandler = this.pointerdownHandler.bind(this);
+        this.pointerupHandler = this.pointerupHandler.bind(this);
+        this.pointermoveHandler = this.pointermoveHandler.bind(this);
+        this.wheelHandler = this.wheelHandler.bind(this);
+
+        this.domElement.addEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.addEventListener('wheel', this.wheelHandler);
+    }
+
+    pointerdownHandler(e) {
+        this.domElement.setPointerCapture(e.pointerId);
+        this.domElement.requestPointerLock();
+        this.domElement.removeEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.addEventListener('pointerup', this.pointerupHandler);
+        this.domElement.addEventListener('pointermove', this.pointermoveHandler);
+    }
+
+    pointerupHandler(e) {
+        this.domElement.releasePointerCapture(e.pointerId);
+        this.domElement.ownerDocument.exitPointerLock();
+        this.domElement.addEventListener('pointerdown', this.pointerdownHandler);
+        this.domElement.removeEventListener('pointerup', this.pointerupHandler);
+        this.domElement.removeEventListener('pointermove', this.pointermoveHandler);
+    }
+
+    pointermoveHandler(e) {
+        const dx = e.movementX;
+        const dy = e.movementY;
+
+        this.pitch -= dy * this.moveSensitivity;
+        this.yaw   -= dx * this.moveSensitivity;
+
+        const twopi = Math.PI * 2;
+        const halfpi = Math.PI / 2;
+
+        this.pitch = Math.min(Math.max(this.pitch, -halfpi), halfpi);
+        this.yaw = ((this.yaw % twopi) + twopi) % twopi;
+    }
+
+    wheelHandler(e) {
+        this.distance *= Math.exp(this.zoomSensitivity * e.deltaY);
+    }
+
+    update() {
+        const transform = this.node.getComponentOfType(Transform);
+        if (!transform) {
+            return;
+        }
+
+        const rotation = quat.create();
+        quat.rotateY(rotation, rotation, this.yaw);
+        quat.rotateX(rotation, rotation, this.pitch);
+        transform.rotation = rotation;
+
+        const translation = [0, 0, this.distance];
+        vec3.rotateX(translation, translation, [0, 0, 0], this.pitch);
+        vec3.rotateY(translation, translation, [0, 0, 0], this.yaw);
+        transform.translation = translation;
+    }
+
+}
--- a/naloga_3/engine/core.js
+++ b/naloga_3/engine/core.js
@@ -0,0 +1,11 @@
+export * from './core/Accessor.js';
+export * from './core/Camera.js';
+export * from './core/Material.js';
+export * from './core/Mesh.js';
+export * from './core/Model.js';
+export * from './core/Node.js';
+export * from './core/Primitive.js';
+export * from './core/Sampler.js';
+export * from './core/Texture.js';
+export * from './core/Transform.js';
+export * from './core/Vertex.js';
--- a/naloga_3/engine/core/Accessor.js
+++ b/naloga_3/engine/core/Accessor.js
@@ -0,0 +1,132 @@
+export class Accessor {
+
+    constructor({
+        buffer,
+        viewLength,
+        viewOffset = 0,
+        offset = 0,
+        stride = componentSize,
+
+        componentType = 'int',
+        componentCount = 1,
+        componentSize = 1,
+        componentSigned = false,
+        componentNormalized = false,
+    } = {}) {
+        this.buffer = buffer;
+        this.offset = offset;
+        this.stride = stride;
+
+        this.componentType = componentType;
+        this.componentCount = componentCount;
+        this.componentSize = componentSize;
+        this.componentSigned = componentSigned;
+        this.componentNormalized = componentNormalized;
+
+        const viewType = this.getViewType({
+            componentType,
+            componentSize,
+            componentSigned,
+        });
+
+        if (viewLength !== undefined) {
+            this.view = new viewType(buffer, viewOffset, viewLength / viewType.BYTES_PER_ELEMENT);
+        } else {
+            this.view = new viewType(buffer, viewOffset);
+        }
+
+        this.offsetInElements = offset / viewType.BYTES_PER_ELEMENT;
+        this.strideInElements = stride / viewType.BYTES_PER_ELEMENT;
+
+        this.count = Math.floor((this.view.length - this.offsetInElements) / this.strideInElements);
+
+        this.normalize = this.getNormalizer({
+            componentType,
+            componentSize,
+            componentSigned,
+            componentNormalized,
+        });
+
+        this.denormalize = this.getDenormalizer({
+            componentType,
+            componentSize,
+            componentSigned,
+            componentNormalized,
+        });
+    }
+
+    get(index) {
+        const start = index * this.strideInElements + this.offsetInElements;
+        const end = start + this.componentCount;
+        return [...this.view.slice(start, end)].map(this.normalize);
+    }
+
+    set(index, value) {
+        const start = index * this.strideInElements + this.offsetInElements;
+        this.view.set(value.map(this.denormalize), start);
+    }
+
+    getNormalizer({
+        componentType,
+        componentSize,
+        componentSigned,
+        componentNormalized,
+    }) {
+        if (!componentNormalized || componentType === 'float') {
+            return x => x;
+        }
+
+        const multiplier = componentSigned
+            ? 2 ** ((componentSize * 8) - 1) - 1
+            : 2 ** (componentSize * 8) - 1;
+
+        return x => Math.max(x / multiplier, -1);
+    }
+
+    getDenormalizer({
+        componentType,
+        componentSize,
+        componentSigned,
+        componentNormalized,
+    }) {
+        if (!componentNormalized || componentType === 'float') {
+            return x => x;
+        }
+
+        const multiplier = componentSigned
+            ? 2 ** ((componentSize * 8) - 1) - 1
+            : 2 ** (componentSize * 8) - 1;
+
+        const min = componentSigned ? -1 : 0;
+        const max = 1;
+
+        return x => Math.floor(0.5 + multiplier * Math.min(Math.max(x, min), max));
+    }
+
+    getViewType({
+        componentType,
+        componentSize,
+        componentSigned,
+    }) {
+        if (componentType === 'float') {
+            if (componentSize === 4) {
+                return Float32Array;
+            }
+        } else if (componentType === 'int') {
+            if (componentSigned) {
+                switch (componentSize) {
+                    case 1: return Int8Array;
+                    case 2: return Int16Array;
+                    case 4: return Int32Array;
+                }
+            } else {
+                switch (componentSize) {
+                    case 1: return Uint8Array;
+                    case 2: return Uint16Array;
+                    case 4: return Uint32Array;
+                }
+            }
+        }
+    }
+
+}
--- a/naloga_3/engine/core/Camera.js
+++ b/naloga_3/engine/core/Camera.js
@@ -0,0 +1,46 @@
+import { mat4 } from 'glm';
+
+export class Camera {
+
+    constructor({
+        orthographic = 0,
+        aspect = 1,
+        fovy = 1,
+        halfy = 1,
+        near = 0.01,
+        far = 1000,
+    } = {}) {
+        this.orthographic = orthographic;
+        this.aspect = aspect;
+        this.fovy = fovy;
+        this.halfy = halfy;
+        this.near = near;
+        this.far = far;
+    }
+
+    get projectionMatrix() {
+        if (this.orthographic === 0) {
+            return this.perspectiveMatrix;
+        } else if (this.orthographic === 1) {
+            return this.orthographicMatrix;
+        } else {
+            const a = this.orthographicMatrix;
+            const b = this.perspectiveMatrix;
+            return mat4.add(mat4.create(),
+                mat4.multiplyScalar(a, a, this.orthographic),
+                mat4.multiplyScalar(b, b, 1 - this.orthographic));
+        }
+    }
+
+    get orthographicMatrix() {
+        const { halfy, aspect, near, far } = this;
+        const halfx = halfy * aspect;
+        return mat4.orthoZO(mat4.create(), -halfx, halfx, -halfy, halfy, near, far);
+    }
+
+    get perspectiveMatrix() {
+        const { fovy, aspect, near, far } = this;
+        return mat4.perspectiveZO(mat4.create(), fovy, aspect, near, far);
+    }
+
+}
--- a/naloga_3/engine/core/Material.js
+++ b/naloga_3/engine/core/Material.js
@@ -0,0 +1,33 @@
+export class Material {
+
+    constructor({
+        baseTexture,
+        emissionTexture,
+        normalTexture,
+        occlusionTexture,
+        roughnessTexture,
+        metalnessTexture,
+
+        baseFactor = [1, 1, 1, 1],
+        emissionFactor = [0, 0, 0],
+        normalFactor = 1,
+        occlusionFactor = 1,
+        roughnessFactor = 1,
+        metalnessFactor = 1,
+    } = {}) {
+        this.baseTexture = baseTexture;
+        this.emissionTexture = emissionTexture;
+        this.normalTexture = normalTexture;
+        this.occlusionTexture = occlusionTexture;
+        this.roughnessTexture = roughnessTexture;
+        this.metalnessTexture = metalnessTexture;
+
+        this.baseFactor = baseFactor;
+        this.emissionFactor = emissionFactor;
+        this.normalFactor = normalFactor;
+        this.occlusionFactor = occlusionFactor;
+        this.roughnessFactor = roughnessFactor;
+        this.metalnessFactor = metalnessFactor;
+    }
+
+}
--- a/naloga_3/engine/core/Mesh.js
+++ b/naloga_3/engine/core/Mesh.js
@@ -0,0 +1,11 @@
+export class Mesh {
+
+    constructor({
+        vertices = [],
+        indices = [],
+    } = {}) {
+        this.vertices = vertices;
+        this.indices = indices;
+    }
+
+}
--- a/naloga_3/engine/core/MeshUtils.js
+++ b/naloga_3/engine/core/MeshUtils.js
@@ -0,0 +1,43 @@
+import { quat, vec3, vec4, mat3, mat4 } from 'glm';
+
+export function transformVertex(vertex, matrix,
+    normalMatrix = mat3.normalFromMat4(mat3.create(), matrix),
+    tangentMatrix = mat3.fromMat4(mat3.create(), matrix),
+) {
+    vec3.transformMat4(vertex.position, vertex.position, matrix);
+    vec3.transformMat3(vertex.normal, vertex.normal, normalMatrix);
+    vec3.transformMat3(vertex.tangent, vertex.tangent, tangentMatrix);
+}
+
+export function transformMesh(mesh, matrix,
+    normalMatrix = mat3.normalFromMat4(mat3.create(), matrix),
+    tangentMatrix = mat3.fromMat4(mat3.create(), matrix),
+) {
+    for (const vertex of mesh.vertices) {
+        transformVertex(vertex, matrix, normalMatrix, tangentMatrix);
+    }
+}
+
+export function calculateAxisAlignedBoundingBox(mesh) {
+    const initial = {
+        min: vec3.clone(mesh.vertices[0].position),
+        max: vec3.clone(mesh.vertices[0].position),
+    };
+
+    return {
+        min: mesh.vertices.reduce((a, b) => vec3.min(a, a, b.position), initial.min),
+        max: mesh.vertices.reduce((a, b) => vec3.max(a, a, b.position), initial.max),
+    };
+}
+
+export function mergeAxisAlignedBoundingBoxes(boxes) {
+    const initial = {
+        min: vec3.clone(boxes[0].min),
+        max: vec3.clone(boxes[0].max),
+    };
+
+    return {
+        min: boxes.reduce(({ min: amin }, { min: bmin }) => vec3.min(amin, amin, bmin), initial),
+        max: boxes.reduce(({ max: amax }, { max: bmax }) => vec3.max(amax, amax, bmax), initial),
+    };
+}
--- a/naloga_3/engine/core/Model.js
+++ b/naloga_3/engine/core/Model.js
@@ -0,0 +1,9 @@
+export class Model {
+
+    constructor({
+        primitives = [],
+    } = {}) {
+        this.primitives = primitives;
+    }
+
+}
--- a/naloga_3/engine/core/Node.js
+++ b/naloga_3/engine/core/Node.js
@@ -0,0 +1,69 @@
+export class Node {
+
+    constructor() {
+        this.children = [];
+        this.parent = null;
+        this.components = [];
+    }
+
+    addChild(node) {
+        node.parent?.removeChild(node);
+        this.children.push(node);
+        node.parent = this;
+    }
+
+    removeChild(node) {
+        const index = this.children.indexOf(node);
+        if (index >= 0) {
+            this.children.splice(index, 1);
+            node.parent = null;
+        }
+    }
+
+    traverse(before, after) {
+        before?.(this);
+        for (const child of this.children) {
+            child.traverse(before, after);
+        }
+        after?.(this);
+    }
+
+    linearize() {
+        const array = [];
+        this.traverse(node => array.push(node));
+        return array;
+    }
+
+    filter(predicate) {
+        return this.linearize().filter(predicate);
+    }
+
+    find(predicate) {
+        return this.linearize().find(predicate);
+    }
+
+    map(transform) {
+        return this.linearize().map(transform);
+    }
+
+    addComponent(component) {
+        this.components.push(component);
+    }
+
+    removeComponent(component) {
+        this.components = this.components.filter(c => c !== component);
+    }
+
+    removeComponentsOfType(type) {
+        this.components = this.components.filter(component => !(component instanceof type));
+    }
+
+    getComponentOfType(type) {
+        return this.components.find(component => component instanceof type);
+    }
+
+    getComponentsOfType(type) {
+        return this.components.filter(component => component instanceof type);
+    }
+
+}
--- a/naloga_3/engine/core/Primitive.js
+++ b/naloga_3/engine/core/Primitive.js
@@ -0,0 +1,11 @@
+export class Primitive {
+
+    constructor({
+        mesh,
+        material,
+    } = {}) {
+        this.mesh = mesh;
+        this.material = material;
+    }
+
+}
--- a/naloga_3/engine/core/Sampler.js
+++ b/naloga_3/engine/core/Sampler.js
@@ -0,0 +1,21 @@
+export class Sampler {
+
+    constructor({
+        minFilter = 'linear',
+        magFilter = 'linear',
+        mipmapFilter = 'linear',
+        addressModeU = 'clamp-to-edge',
+        addressModeV = 'clamp-to-edge',
+        addressModeW = 'clamp-to-edge',
+        maxAnisotropy = 1,
+    } = {}) {
+        this.minFilter = minFilter;
+        this.magFilter = magFilter;
+        this.mipmapFilter = mipmapFilter;
+        this.addressModeU = addressModeU;
+        this.addressModeV = addressModeV;
+        this.addressModeW = addressModeW;
+        this.maxAnisotropy = maxAnisotropy;
+    }
+
+}
--- a/naloga_3/engine/core/SceneUtils.js
+++ b/naloga_3/engine/core/SceneUtils.js
@@ -0,0 +1,42 @@
+import { mat4 } from 'glm';
+
+import { Camera } from './Camera.js';
+import { Model } from './Model.js';
+import { Transform } from './Transform.js';
+
+export function getLocalModelMatrix(node) {
+    const matrix = mat4.create();
+    for (const transform of node.getComponentsOfType(Transform)) {
+        mat4.mul(matrix, matrix, transform.matrix);
+    }
+    return matrix;
+}
+
+export function getGlobalModelMatrix(node) {
+    if (node.parent) {
+        const parentMatrix = getGlobalModelMatrix(node.parent);
+        const modelMatrix = getLocalModelMatrix(node);
+        return mat4.multiply(parentMatrix, parentMatrix, modelMatrix);
+    } else {
+        return getLocalModelMatrix(node);
+    }
+}
+
+export function getLocalViewMatrix(node) {
+    const matrix = getLocalModelMatrix(node);
+    return mat4.invert(matrix, matrix);
+}
+
+export function getGlobalViewMatrix(node) {
+    const matrix = getGlobalModelMatrix(node);
+    return mat4.invert(matrix, matrix);
+}
+
+export function getProjectionMatrix(node) {
+    const camera = node.getComponentOfType(Camera);
+    return camera ? camera.projectionMatrix : mat4.create();
+}
+
+export function getModels(node) {
+    return node.getComponentsOfType(Model);
+}
--- a/naloga_3/engine/core/Texture.js
+++ b/naloga_3/engine/core/Texture.js
@@ -0,0 +1,21 @@
+export class Texture {
+
+    constructor({
+        image,
+        sampler,
+        isSRGB = false,
+    } = {}) {
+        this.image = image;
+        this.sampler = sampler;
+        this.isSRGB = isSRGB;
+    }
+
+    get width() {
+        return this.image.width;
+    }
+
+    get height() {
+        return this.image.height;
+    }
+
+}
--- a/naloga_3/engine/core/Transform.js
+++ b/naloga_3/engine/core/Transform.js
@@ -0,0 +1,30 @@
+import { mat4 } from 'glm';
+
+export class Transform {
+
+    constructor({
+        rotation = [0, 0, 0, 1],
+        translation = [0, 0, 0],
+        scale = [1, 1, 1],
+        matrix,
+    } = {}) {
+        this.rotation = rotation;
+        this.translation = translation;
+        this.scale = scale;
+        if (matrix) {
+            this.matrix = matrix;
+        }
+    }
+
+    get matrix() {
+        return mat4.fromRotationTranslationScale(mat4.create(),
+            this.rotation, this.translation, this.scale);
+    }
+
+    set matrix(matrix) {
+        mat4.getRotation(this.rotation, matrix);
+        mat4.getTranslation(this.translation, matrix);
+        mat4.getScaling(this.scale, matrix);
+    }
+
+}
--- a/naloga_3/engine/core/Vertex.js
+++ b/naloga_3/engine/core/Vertex.js
@@ -0,0 +1,15 @@
+export class Vertex {
+
+    constructor({
+        position = [0, 0, 0],
+        texcoords = [0, 0],
+        normal = [0, 0, 0],
+        tangent = [0, 0, 0],
+    } = {}) {
+        this.position = position;
+        this.texcoords = texcoords;
+        this.normal = normal;
+        this.tangent = tangent;
+    }
+
+}
--- a/naloga_3/engine/core/VertexUtils.js
+++ b/naloga_3/engine/core/VertexUtils.js
@@ -0,0 +1,35 @@
+import { Accessor } from './Accessor.js';
+
+export function parseFormat(format) {
+    const regex = /(?<type>float|((?<sign>u|s)(?<norm>int|norm)))(?<bits>\d+)x(?<count>\d+)/;
+    const groups = format.match(regex).groups;
+
+    return {
+        componentType: groups.type === 'float' ? 'float' : 'int',
+        componentNormalized: groups.norm === 'norm',
+        componentSigned: groups.sign === 's',
+        componentSize: Number(groups.bits) / 8,
+        componentCount: Number(groups.count),
+    };
+}
+
+export function createVertexBuffer(vertices, layout) {
+    const buffer = new ArrayBuffer(layout.arrayStride * vertices.length);
+    const accessors = layout.attributes.map(attribute => new Accessor({
+        buffer,
+        stride: layout.arrayStride,
+        ...parseFormat(attribute.format),
+        ...attribute,
+    }));
+
+    for (let i = 0; i < vertices.length; i++) {
+        const vertex = vertices[i];
+        for (let j = 0; j < layout.attributes.length; j++) {
+            const accessor = accessors[j];
+            const attribute = layout.attributes[j].name;
+            accessor.set(i, vertex[attribute]);
+        }
+    }
+
+    return buffer;
+}
--- a/naloga_3/engine/loaders/GLTFLoader.js
+++ b/naloga_3/engine/loaders/GLTFLoader.js
@@ -0,0 +1,483 @@
+import {
+    Accessor,
+    Camera,
+    Material,
+    Mesh,
+    Model,
+    Node,
+    Primitive,
+    Sampler,
+    Texture,
+    Transform,
+    Vertex,
+} from '../core.js';
+
+// TODO: GLB support
+// TODO: accessors with no buffer views (zero-initialized)
+// TODO: image from buffer view
+// TODO: mipmaps
+// TODO: material texcoord sets
+// TODO: material alpha, doubleSided
+
+export class GLTFLoader {
+
+    // Loads the GLTF JSON file and all buffers and images that it references.
+    // It also creates a cache for all future resource loading.
+    async load(url) {
+        this.gltfUrl = new URL(url, window.location);
+        this.gltf = await this.fetchJson(this.gltfUrl);
+        this.defaultScene = this.gltf.scene ?? 0;
+        this.cache = new Map();
+
+        await Promise.all(this.gltf.buffers?.map(buffer => this.preloadBuffer(buffer)) ?? []);
+        await Promise.all(this.gltf.images?.map(image => this.preloadImage(image)) ?? []);
+    }
+
+    // Finds an object in list at the given index, or if the 'name'
+    // property matches the given name.
+    findByNameOrIndex(list, nameOrIndex) {
+        if (typeof nameOrIndex === 'number') {
+            return list[nameOrIndex];
+        } else {
+            return list.find(element => element.name === nameOrIndex);
+        }
+    }
+
+    fetchJson(url) {
+        return fetch(url)
+            .then(response => response.json());
+    }
+
+    fetchBuffer(url) {
+        return fetch(url)
+            .then(response => response.arrayBuffer());
+    }
+
+    fetchImage(url) {
+        return fetch(url)
+            .then(response => response.blob())
+            .then(blob => createImageBitmap(blob));
+    }
+
+    async preloadImage(gltfSpec) {
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        if (gltfSpec.uri) {
+            const url = new URL(gltfSpec.uri, this.gltfUrl);
+            const image = await this.fetchImage(url);
+            this.cache.set(gltfSpec, image);
+            return image;
+        } else {
+            const bufferView = this.gltf.bufferViews[gltfSpec.bufferView];
+            const buffer = this.loadBuffer(bufferView.buffer);
+            const dataView = new DataView(buffer, bufferView.byteOffset ?? 0, bufferView.byteLength);
+            const blob = new Blob([dataView], { type: gltfSpec.mimeType });
+            const url = URL.createObjectURL(blob);
+            const image = await this.fetchImage(url);
+            URL.revokeObjectURL(url);
+            this.cache.set(gltfSpec, image);
+            return image;
+        }
+    }
+
+    async preloadBuffer(gltfSpec) {
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const url = new URL(gltfSpec.uri, this.gltfUrl);
+        const buffer = await this.fetchBuffer(url);
+        this.cache.set(gltfSpec, buffer);
+        return buffer;
+    }
+
+    loadImage(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.images, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+
+        return this.cache.get(gltfSpec);
+    }
+
+    loadBuffer(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.buffers, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+
+        return this.cache.get(gltfSpec);
+    }
+
+    loadSampler(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.samplers, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const minFilter = {
+            9728: 'nearest',
+            9729: 'linear',
+            9984: 'nearest',
+            9985: 'linear',
+            9986: 'nearest',
+            9987: 'linear',
+        };
+
+        const magFilter = {
+            9728: 'nearest',
+            9729: 'linear',
+        };
+
+        const mipmapFilter = {
+            9728: 'nearest',
+            9729: 'linear',
+            9984: 'nearest',
+            9985: 'nearest',
+            9986: 'linear',
+            9987: 'linear',
+        };
+
+        const addressMode = {
+            33071: 'clamp-to-edge',
+            33648: 'mirror-repeat',
+            10497: 'repeat',
+        };
+
+        const sampler = new Sampler({
+            minFilter: minFilter[gltfSpec.minFilter ?? 9729],
+            magFilter: magFilter[gltfSpec.magFilter ?? 9729],
+            mipmapFilter: mipmapFilter[gltfSpec.minFilter ?? 9729],
+            addressModeU: addressMode[gltfSpec.wrapS ?? 10497],
+            addressModeV: addressMode[gltfSpec.wrapT ?? 10497],
+        });
+
+        this.cache.set(gltfSpec, sampler);
+        return sampler;
+    }
+
+    loadTexture(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.textures, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const options = {};
+        if (gltfSpec.source !== undefined) {
+            options.image = this.loadImage(gltfSpec.source);
+        }
+        if (gltfSpec.sampler !== undefined) {
+            options.sampler = this.loadSampler(gltfSpec.sampler);
+        } else {
+            options.sampler = new Sampler();
+        }
+
+        const texture = new Texture(options);
+
+        this.cache.set(gltfSpec, texture);
+        return texture;
+    }
+
+    loadMaterial(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.materials, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const options = {};
+        const pbr = gltfSpec.pbrMetallicRoughness;
+        if (pbr) {
+            if (pbr.baseColorTexture) {
+                options.baseTexture = this.loadTexture(pbr.baseColorTexture.index);
+                options.baseTexture.isSRGB = true;
+            }
+            if (pbr.metallicRoughnessTexture) {
+                options.metalnessTexture = this.loadTexture(pbr.metallicRoughnessTexture.index);
+                options.roughnessTexture = this.loadTexture(pbr.metallicRoughnessTexture.index);
+            }
+            options.baseFactor = pbr.baseColorFactor;
+            options.metalnessFactor = pbr.metallicFactor;
+            options.roughnessFactor = pbr.roughnessFactor;
+        }
+
+        if (gltfSpec.normalTexture) {
+            options.normalTexture = this.loadTexture(gltfSpec.normalTexture.index);
+            options.normalFactor = gltfSpec.normalTexture.scale;
+        }
+
+        if (gltfSpec.emissiveTexture) {
+            options.emissionTexture = this.loadTexture(gltfSpec.emissiveTexture.index);
+            options.emissionTexture.isSRGB = true;
+            options.emissionFactor = gltfSpec.emissiveFactor;
+        }
+
+        if (gltfSpec.occlusionTexture) {
+            options.occlusionTexture = this.loadTexture(gltfSpec.occlusionTexture.index);
+            options.occlusionFactor = gltfSpec.occlusionTexture.strength;
+        }
+
+        const material = new Material(options);
+
+        this.cache.set(gltfSpec, material);
+        return material;
+    }
+
+    loadAccessor(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.accessors, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        if (gltfSpec.bufferView === undefined) {
+            console.warn('Accessor does not reference a buffer view');
+            return null;
+        }
+
+        const bufferView = this.gltf.bufferViews[gltfSpec.bufferView];
+        const buffer = this.loadBuffer(bufferView.buffer);
+
+        const componentType = {
+            5120: 'int',
+            5121: 'int',
+            5122: 'int',
+            5123: 'int',
+            5124: 'int',
+            5125: 'int',
+            5126: 'float',
+        }[gltfSpec.componentType];
+
+        const componentSize = {
+            5120: 1,
+            5121: 1,
+            5122: 2,
+            5123: 2,
+            5124: 4,
+            5125: 4,
+            5126: 4,
+        }[gltfSpec.componentType];
+
+        const componentSigned = {
+            5120: true,
+            5121: false,
+            5122: true,
+            5123: false,
+            5124: true,
+            5125: false,
+            5126: false,
+        }[gltfSpec.componentType];
+
+        const componentCount = {
+            SCALAR: 1,
+            VEC2: 2,
+            VEC3: 3,
+            VEC4: 4,
+            MAT2: 4,
+            MAT3: 9,
+            MAT4: 16,
+        }[gltfSpec.type];
+
+        const componentNormalized = gltfSpec.normalized ?? false;
+
+        const stride = bufferView.byteStride ?? (componentSize * componentCount);
+        const offset = gltfSpec.byteOffset ?? 0;
+        const viewOffset = bufferView.byteOffset ?? 0;
+        const viewLength = bufferView.byteLength;
+
+        const accessor = new Accessor({
+            buffer,
+            viewLength,
+            viewOffset,
+            offset,
+            stride,
+
+            componentType,
+            componentCount,
+            componentSize,
+            componentSigned,
+            componentNormalized,
+        });
+
+        this.cache.set(gltfSpec, accessor);
+        return accessor;
+    }
+
+    createMeshFromPrimitive(spec) {
+        if (spec.attributes.POSITION === undefined) {
+            console.warn('No position in mesh');
+            return new Mesh();
+        }
+
+        if (spec.indices === undefined) {
+            console.warn('No indices in mesh');
+            return new Mesh();
+        }
+
+        const accessors = {};
+        for (const attribute in spec.attributes) {
+            accessors[attribute] = this.loadAccessor(spec.attributes[attribute]);
+        }
+
+        const position = accessors.POSITION;
+        const texcoords = accessors.TEXCOORD_0;
+        const normal = accessors.NORMAL;
+        const tangent = accessors.TANGENT;
+
+        const vertexCount = position.count;
+        const vertices = [];
+
+        for (let i = 0; i < vertexCount; i++) {
+            const options = {};
+
+            if (position) { options.position = position.get(i); }
+            if (texcoords) { options.texcoords = texcoords.get(i); }
+            if (normal) { options.normal = normal.get(i); }
+            if (tangent) { options.tangent = tangent.get(i); }
+
+            vertices.push(new Vertex(options));
+        }
+
+        const indices = [];
+        const indicesAccessor = this.loadAccessor(spec.indices);
+        const indexCount = indicesAccessor.count;
+
+        for (let i = 0; i < indexCount; i++) {
+            indices.push(indicesAccessor.get(i));
+        }
+
+        return new Mesh({ vertices, indices });
+    }
+
+    loadMesh(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.meshes, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const primitives = [];
+        for (const primitiveSpec of gltfSpec.primitives) {
+            if (primitiveSpec.mode !== 4 && primitiveSpec.mode !== undefined) {
+                console.warn(`GLTFLoader: skipping primitive with mode ${primitiveSpec.mode}`);
+                continue;
+            }
+
+            const options = {};
+            options.mesh = this.createMeshFromPrimitive(primitiveSpec);
+
+            if (primitiveSpec.material !== undefined) {
+                options.material = this.loadMaterial(primitiveSpec.material);
+            }
+
+            primitives.push(new Primitive(options));
+        }
+
+        const model = new Model({ primitives });
+
+        this.cache.set(gltfSpec, model);
+        return model;
+    }
+
+    loadCamera(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.cameras, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const options = {};
+        if (gltfSpec.type === 'perspective') {
+            const { aspectRatio, yfov, znear, zfar } = gltfSpec.perspective;
+            Object.assign(options, {
+                orthographic: 0,
+                aspect: aspectRatio,
+                fovy: yfov,
+                near: znear,
+                far: zfar,
+            });
+        } else if (gltfSpec.type === 'orthographic') {
+            const { xmag, ymag, znear, zfar } = gltfSpec.orthographic;
+            Object.assign(options, {
+                orthographic: 1,
+                aspect: xmag / ymag,
+                halfy: ymag,
+                near: znear,
+                far: zfar,
+            });
+        }
+
+        const camera = new Camera(options);
+
+        this.cache.set(gltfSpec, camera);
+        return camera;
+    }
+
+    loadNode(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.nodes, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const node = new Node();
+
+        node.addComponent(new Transform(gltfSpec));
+
+        if (gltfSpec.children) {
+            for (const childIndex of gltfSpec.children) {
+                node.addChild(this.loadNode(childIndex));
+            }
+        }
+
+        if (gltfSpec.camera !== undefined) {
+            node.addComponent(this.loadCamera(gltfSpec.camera));
+        }
+
+        if (gltfSpec.mesh !== undefined) {
+            node.addComponent(this.loadMesh(gltfSpec.mesh));
+        }
+
+        this.cache.set(gltfSpec, node);
+        return node;
+    }
+
+    loadScene(nameOrIndex) {
+        const gltfSpec = this.findByNameOrIndex(this.gltf.scenes, nameOrIndex);
+        if (!gltfSpec) {
+            return null;
+        }
+        if (this.cache.has(gltfSpec)) {
+            return this.cache.get(gltfSpec);
+        }
+
+        const scene = new Node();
+        if (gltfSpec.nodes) {
+            for (const nodeIndex of gltfSpec.nodes) {
+                scene.addChild(this.loadNode(nodeIndex));
+            }
+        }
+
+        this.cache.set(gltfSpec, scene);
+        return scene;
+    }
+
+}
--- a/naloga_3/engine/loaders/ImageLoader.js
+++ b/naloga_3/engine/loaders/ImageLoader.js
@@ -0,0 +1,10 @@
+export class ImageLoader {
+
+    async load(url) {
+        const response = await fetch(url);
+        const blob = await response.blob();
+        const imageBitmap = await createImageBitmap(blob);
+        return imageBitmap;
+    }
+
+}
--- a/naloga_3/engine/loaders/JSONLoader.js
+++ b/naloga_3/engine/loaders/JSONLoader.js
@@ -0,0 +1,24 @@
+import { Mesh, Vertex } from '../core.js';
+
+export class JSONLoader {
+
+    async loadMesh(url) {
+        const response = await fetch(url);
+        const json = await response.json();
+
+        const vertices = [];
+        const vertexCount = json.positions.length / 3;
+        for (let i = 0; i < vertexCount; i++) {
+            const position = json?.positions?.slice(i * 3, (i + 1) * 3);
+            const texcoords = json?.texcoords?.slice(i * 2, (i + 1) * 2);
+            const normal = json?.normals?.slice(i * 3, (i + 1) * 3);
+            const tangent = json?.tangents?.slice(i * 3, (i + 1) * 3);
+            vertices.push(new Vertex({ position, texcoords, normal, tangent }));
+        }
+
+        const indices = json.indices;
+
+        return new Mesh({ vertices, indices });
+    }
+
+}
--- a/naloga_3/engine/loaders/OBJLoader.js
+++ b/naloga_3/engine/loaders/OBJLoader.js
@@ -0,0 +1,70 @@
+import { Mesh, Vertex } from '../core.js';
+
+export class OBJLoader {
+
+    async loadMesh(url) {
+        const response = await fetch(url);
+        const text = await response.text();
+
+        const lines = text.split('\n');
+
+        const vRegex = /v\s+(\S+)\s+(\S+)\s+(\S+)\s*/;
+        const vData = lines
+            .filter(line => vRegex.test(line))
+            .map(line => [...line.match(vRegex)].slice(1))
+            .map(entry => entry.map(entry => Number(entry)));
+
+        const vnRegex = /vn\s+(\S+)\s+(\S+)\s+(\S+)\s*/;
+        const vnData = lines
+            .filter(line => vnRegex.test(line))
+            .map(line => [...line.match(vnRegex)].slice(1))
+            .map(entry => entry.map(entry => Number(entry)));
+
+        const vtRegex = /vt\s+(\S+)\s+(\S+)\s*/;
+        const vtData = lines
+            .filter(line => vtRegex.test(line))
+            .map(line => [...line.match(vtRegex)].slice(1))
+            .map(entry => entry.map(entry => Number(entry)));
+
+        function triangulate(list) {
+            const triangles = [];
+            for (let i = 2; i < list.length; i++) {
+                triangles.push(list[0], list[i - 1], list[i]);
+            }
+            return triangles;
+        }
+
+        const fRegex = /f\s+(.*)/;
+        const fData = lines
+            .filter(line => fRegex.test(line))
+            .map(line => line.match(fRegex)[1])
+            .map(line => line.trim().split(/\s+/))
+            .flatMap(face => triangulate(face));
+
+        const vertices = [];
+        const indices = [];
+        const cache = {};
+        let cacheLength = 0;
+        const indicesRegex = /(\d+)(\/(\d+))?(\/(\d+))?/;
+
+        for (const id of fData) {
+            if (id in cache) {
+                indices.push(cache[id]);
+            } else {
+                cache[id] = cacheLength;
+                indices.push(cacheLength);
+                const [,vIndex,,vtIndex,,vnIndex] = [...id.match(indicesRegex)]
+                    .map(entry => Number(entry) - 1);
+                vertices.push(new Vertex({
+                    position: vData[vIndex],
+                    normal: vnData[vnIndex],
+                    texcoords: vtData[vtIndex],
+                }));
+                cacheLength++;
+            }
+        }
+
+        return new Mesh({ vertices, indices });
+    }
+
+}
--- a/naloga_3/engine/renderers/BaseRenderer.js
+++ b/naloga_3/engine/renderers/BaseRenderer.js
@@ -0,0 +1,75 @@
+import { mat4 } from 'glm';
+
+import * as WebGPU from '../WebGPU.js';
+
+import { createVertexBuffer } from '../core/VertexUtils.js';
+
+export class BaseRenderer {
+
+    constructor(canvas) {
+        this.canvas = canvas;
+        this.gpuObjects = new WeakMap();
+    }
+
+    async initialize() {
+        const adapter = await navigator.gpu.requestAdapter();
+        const device = await adapter.requestDevice();
+        const context = this.canvas.getContext('webgpu');
+        const format = navigator.gpu.getPreferredCanvasFormat();
+        context.configure({ device, format });
+
+        this.device = device;
+        this.context = context;
+        this.format = format;
+    }
+
+    prepareImage(image, isSRGB = false) {
+        if (this.gpuObjects.has(image)) {
+            return this.gpuObjects.get(image);
+        }
+
+        const gpuTexture = WebGPU.createTexture(this.device, {
+            source: image,
+            format: isSRGB ? 'rgba8unorm-srgb' : 'rgba8unorm',
+        });
+
+        const gpuObjects = { gpuTexture };
+        this.gpuObjects.set(image, gpuObjects);
+        return gpuObjects;
+    }
+
+    prepareSampler(sampler) {
+        if (this.gpuObjects.has(sampler)) {
+            return this.gpuObjects.get(sampler);
+        }
+
+        const gpuSampler = this.device.createSampler(sampler);
+
+        const gpuObjects = { gpuSampler };
+        this.gpuObjects.set(sampler, gpuObjects);
+        return gpuObjects;
+    }
+
+    prepareMesh(mesh, layout) {
+        if (this.gpuObjects.has(mesh)) {
+            return this.gpuObjects.get(mesh);
+        }
+
+        const vertexBufferArrayBuffer = createVertexBuffer(mesh.vertices, layout);
+        const vertexBuffer = WebGPU.createBuffer(this.device, {
+            data: vertexBufferArrayBuffer,
+            usage: GPUBufferUsage.VERTEX,
+        });
+
+        const indexBufferArrayBuffer = new Uint32Array(mesh.indices).buffer;
+        const indexBuffer = WebGPU.createBuffer(this.device, {
+            data: indexBufferArrayBuffer,
+            usage: GPUBufferUsage.INDEX,
+        });
+
+        const gpuObjects = { vertexBuffer, indexBuffer };
+        this.gpuObjects.set(mesh, gpuObjects);
+        return gpuObjects;
+    }
+
+}
--- a/naloga_3/engine/renderers/UnlitRenderer.js
+++ b/naloga_3/engine/renderers/UnlitRenderer.js
@@ -0,0 +1,236 @@
+import { mat4 } from 'glm';
+
+import * as WebGPU from '../WebGPU.js';
+
+import { Camera } from '../core.js';
+
+import {
+    getLocalModelMatrix,
+    getGlobalViewMatrix,
+    getProjectionMatrix,
+    getModels,
+} from '../core/SceneUtils.js';
+
+import { BaseRenderer } from './BaseRenderer.js';
+
+const vertexBufferLayout = {
+    arrayStride: 20,
+    attributes: [
+        {
+            name: 'position',
+            shaderLocation: 0,
+            offset: 0,
+            format: 'float32x3',
+        },
+        {
+            name: 'texcoords',
+            shaderLocation: 1,
+            offset: 12,
+            format: 'float32x2',
+        },
+    ],
+};
+
+export class UnlitRenderer extends BaseRenderer {
+
+    constructor(canvas) {
+        super(canvas);
+    }
+
+    async initialize() {
+        await super.initialize();
+
+        const code = await fetch(new URL('UnlitRenderer.wgsl', import.meta.url))
+            .then(response => response.text());
+        const module = this.device.createShaderModule({ code });
+
+        this.pipeline = await this.device.createRenderPipelineAsync({
+            layout: 'auto',
+            vertex: {
+                module,
+                entryPoint: 'vertex',
+                buffers: [ vertexBufferLayout ],
+            },
+            fragment: {
+                module,
+                entryPoint: 'fragment',
+                targets: [{ format: this.format }],
+            },
+            depthStencil: {
+                format: 'depth24plus',
+                depthWriteEnabled: true,
+                depthCompare: 'less',
+            },
+        });
+
+        this.recreateDepthTexture();
+    }
+
+    recreateDepthTexture() {
+        this.depthTexture?.destroy();
+        this.depthTexture = this.device.createTexture({
+            format: 'depth24plus',
+            size: [this.canvas.width, this.canvas.height],
+            usage: GPUTextureUsage.RENDER_ATTACHMENT,
+        });
+    }
+
+    prepareNode(node) {
+        if (this.gpuObjects.has(node)) {
+            return this.gpuObjects.get(node);
+        }
+
+        const modelUniformBuffer = this.device.createBuffer({
+            size: 128,
+            usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
+        });
+
+        const modelBindGroup = this.device.createBindGroup({
+            layout: this.pipeline.getBindGroupLayout(1),
+            entries: [
+                { binding: 0, resource: { buffer: modelUniformBuffer } },
+            ],
+        });
+
+        const gpuObjects = { modelUniformBuffer, modelBindGroup };
+        this.gpuObjects.set(node, gpuObjects);
+        return gpuObjects;
+    }
+
+    prepareCamera(camera) {
+        if (this.gpuObjects.has(camera)) {
+            return this.gpuObjects.get(camera);
+        }
+
+        const cameraUniformBuffer = this.device.createBuffer({
+            size: 128,
+            usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
+        });
+
+        const cameraBindGroup = this.device.createBindGroup({
+            layout: this.pipeline.getBindGroupLayout(0),
+            entries: [
+                { binding: 0, resource: { buffer: cameraUniformBuffer } },
+            ],
+        });
+
+        const gpuObjects = { cameraUniformBuffer, cameraBindGroup };
+        this.gpuObjects.set(camera, gpuObjects);
+        return gpuObjects;
+    }
+
+    prepareTexture(texture) {
+        if (this.gpuObjects.has(texture)) {
+            return this.gpuObjects.get(texture);
+        }
+
+        const { gpuTexture } = this.prepareImage(texture.image); // ignore sRGB
+        const { gpuSampler } = this.prepareSampler(texture.sampler);
+
+        const gpuObjects = { gpuTexture, gpuSampler };
+        this.gpuObjects.set(texture, gpuObjects);
+        return gpuObjects;
+    }
+
+    prepareMaterial(material) {
+        if (this.gpuObjects.has(material)) {
+            return this.gpuObjects.get(material);
+        }
+
+        const baseTexture = this.prepareTexture(material.baseTexture);
+
+        const materialUniformBuffer = this.device.createBuffer({
+            size: 16,
+            usage: GPUBufferUsage.UNIFORM | GPUBufferUsage.COPY_DST,
+        });
+
+        const materialBindGroup = this.device.createBindGroup({
+            layout: this.pipeline.getBindGroupLayout(2),
+            entries: [
+                { binding: 0, resource: { buffer: materialUniformBuffer } },
+                { binding: 1, resource: baseTexture.gpuTexture.createView() },
+                { binding: 2, resource: baseTexture.gpuSampler },
+            ],
+        });
+
+        const gpuObjects = { materialUniformBuffer, materialBindGroup };
+        this.gpuObjects.set(material, gpuObjects);
+        return gpuObjects;
+    }
+
+    render(scene, camera) {
+        if (this.depthTexture.width !== this.canvas.width || this.depthTexture.height !== this.canvas.height) {
+            this.recreateDepthTexture();
+        }
+
+        const encoder = this.device.createCommandEncoder();
+        this.renderPass = encoder.beginRenderPass({
+            colorAttachments: [
+                {
+                    view: this.context.getCurrentTexture().createView(),
+                    clearValue: [1, 1, 1, 1],
+                    loadOp: 'clear',
+                    storeOp: 'store',
+                },
+            ],
+            depthStencilAttachment: {
+                view: this.depthTexture.createView(),
+                depthClearValue: 1,
+                depthLoadOp: 'clear',
+                depthStoreOp: 'discard',
+            },
+        });
+        this.renderPass.setPipeline(this.pipeline);
+
+        const cameraComponent = camera.getComponentOfType(Camera);
+        const viewMatrix = getGlobalViewMatrix(camera);
+        const projectionMatrix = getProjectionMatrix(camera);
+        const { cameraUniformBuffer, cameraBindGroup } = this.prepareCamera(cameraComponent);
+        this.device.queue.writeBuffer(cameraUniformBuffer, 0, viewMatrix);
+        this.device.queue.writeBuffer(cameraUniformBuffer, 64, projectionMatrix);
+        this.renderPass.setBindGroup(0, cameraBindGroup);
+
+        this.renderNode(scene);
+
+        this.renderPass.end();
+        this.device.queue.submit([encoder.finish()]);
+    }
+
+    renderNode(node, modelMatrix = mat4.create()) {
+        const localMatrix = getLocalModelMatrix(node);
+        modelMatrix = mat4.multiply(mat4.create(), modelMatrix, localMatrix);
+
+        const { modelUniformBuffer, modelBindGroup } = this.prepareNode(node);
+        const normalMatrix = mat4.normalFromMat4(mat4.create(), modelMatrix);
+        this.device.queue.writeBuffer(modelUniformBuffer, 0, modelMatrix);
+        this.device.queue.writeBuffer(modelUniformBuffer, 64, normalMatrix);
+        this.renderPass.setBindGroup(1, modelBindGroup);
+
+        for (const model of getModels(node)) {
+            this.renderModel(model);
+        }
+
+        for (const child of node.children) {
+            this.renderNode(child, modelMatrix);
+        }
+    }
+
+    renderModel(model) {
+        for (const primitive of model.primitives) {
+            this.renderPrimitive(primitive);
+        }
+    }
+
+    renderPrimitive(primitive) {
+        const { materialUniformBuffer, materialBindGroup } = this.prepareMaterial(primitive.material);
+        this.device.queue.writeBuffer(materialUniformBuffer, 0, new Float32Array(primitive.material.baseFactor));
+        this.renderPass.setBindGroup(2, materialBindGroup);
+
+        const { vertexBuffer, indexBuffer } = this.prepareMesh(primitive.mesh, vertexBufferLayout);
+        this.renderPass.setVertexBuffer(0, vertexBuffer);
+        this.renderPass.setIndexBuffer(indexBuffer, 'uint32');
+
+        this.renderPass.drawIndexed(primitive.mesh.indices.length);
+    }
+
+}
--- a/naloga_3/engine/renderers/UnlitRenderer.wgsl
+++ b/naloga_3/engine/renderers/UnlitRenderer.wgsl
@@ -0,0 +1,56 @@
+struct VertexInput {
+    @location(0) position: vec3f,
+    @location(1) texcoords: vec2f,
+}
+
+struct VertexOutput {
+    @builtin(position) position: vec4f,
+    @location(1) texcoords: vec2f,
+}
+
+struct FragmentInput {
+    @location(1) texcoords: vec2f,
+}
+
+struct FragmentOutput {
+    @location(0) color: vec4f,
+}
+
+struct CameraUniforms {
+    viewMatrix: mat4x4f,
+    projectionMatrix: mat4x4f,
+}
+
+struct ModelUniforms {
+    modelMatrix: mat4x4f,
+    normalMatrix: mat3x3f,
+}
+
+struct MaterialUniforms {
+    baseFactor: vec4f,
+}
+
+@group(0) @binding(0) var<uniform> camera: CameraUniforms;
+@group(1) @binding(0) var<uniform> model: ModelUniforms;
+@group(2) @binding(0) var<uniform> material: MaterialUniforms;
+@group(2) @binding(1) var baseTexture: texture_2d<f32>;
+@group(2) @binding(2) var baseSampler: sampler;
+
+@vertex
+fn vertex(input: VertexInput) -> VertexOutput {
+    var output: VertexOutput;
+
+    output.position = camera.projectionMatrix * camera.viewMatrix * model.modelMatrix * vec4(input.position, 1);
+    output.texcoords = input.texcoords;
+
+    return output;
+}
+
+@fragment
+fn fragment(input: FragmentInput) -> FragmentOutput {
+    var output: FragmentOutput;
+
+    output.color = textureSample(baseTexture, baseSampler, input.texcoords) * material.baseFactor;
+
+    return output;
+}
--- a/naloga_3/engine/style.css
+++ b/naloga_3/engine/style.css
@@ -0,0 +1,56 @@
+body, html {
+    margin: 0;
+    padding: 0;
+}
+
+* {
+    font-family: sans-serif;
+}
+
+.fullscreen {
+    width: 100vw;
+    height: 100vh;
+    overflow: hidden;
+}
+
+.fullscreen > * {
+    width: 100%;
+    height: 100%;
+}
+
+.overlay {
+    position: fixed;
+    left: 0;
+    top: 0;
+}
+
+.no-touch {
+    touch-action: none;
+}
+
+.pixelated {
+    image-rendering: pixelated;
+}
+
+.loader-container {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+}
+
+.loader {
+    width: 100px;
+    height: 100px;
+
+    border: 15px solid transparent;
+    border-radius: 50%;
+    border-top-color: #999;
+    border-bottom-color: #999;
+
+    animation: spin 2s ease-in-out infinite;
+}
+
+@keyframes spin {
+      0% { transform: rotate(0deg); }
+    100% { transform: rotate(1800deg); }
+}
--- a/naloga_3/engine/systems/ResizeSystem.js
+++ b/naloga_3/engine/systems/ResizeSystem.js
@@ -0,0 +1,84 @@
+export class ResizeSystem {
+
+    constructor({
+        canvas,
+        resize,
+        resolutionFactor = 1,
+        minWidth = 1,
+        minHeight = 1,
+        maxWidth = Infinity,
+        maxHeight = Infinity,
+    } = {}) {
+        this._resize = this._resize.bind(this);
+
+        this.canvas = canvas;
+        this.resize = resize;
+
+        this.resolutionFactor = resolutionFactor;
+        this.minCanvasSize = {
+            width: minWidth,
+            height: minHeight,
+        };
+        this.maxCanvasSize = {
+            width: maxWidth,
+            height: maxHeight,
+        };
+        this.lastSize = {
+            width: null,
+            height: null,
+        };
+    }
+
+    start() {
+        if (this._resizeFrame) {
+            return;
+        }
+
+        this._resizeFrame = requestAnimationFrame(this._resize);
+    }
+
+    stop() {
+        if (!this._resizeFrame) {
+            return;
+        }
+
+        this._resizeFrame = cancelAnimationFrame(this._resizeFrame);
+    }
+
+    _resize() {
+        this._resizeFrame = requestAnimationFrame(this._resize);
+
+        const displayRect = this.canvas.getBoundingClientRect();
+        if (displayRect.width === this.lastSize.width && displayRect.height === this.lastSize.height) {
+            return;
+        }
+
+        this.lastSize = {
+            width: displayRect.width,
+            height: displayRect.height,
+        };
+
+        const displaySize = {
+            width: displayRect.width * devicePixelRatio,
+            height: displayRect.height * devicePixelRatio,
+        };
+
+        const unclampedSize = {
+            width: Math.round(displaySize.width * this.resolutionFactor),
+            height: Math.round(displaySize.height * this.resolutionFactor),
+        };
+
+        const canvasSize = {
+            width: Math.min(Math.max(unclampedSize.width, this.minCanvasSize.width), this.maxCanvasSize.width),
+            height: Math.min(Math.max(unclampedSize.height, this.minCanvasSize.height), this.maxCanvasSize.height),
+        };
+
+        if (this.canvas.width !== canvasSize.width || this.canvas.height !== canvasSize.height) {
+            this.canvas.width = canvasSize.width;
+            this.canvas.height = canvasSize.height;
+        }
+
+        this.resize?.({ displaySize, canvasSize });
+    }
+
+}
--- a/naloga_3/engine/systems/UpdateSystem.js
+++ b/naloga_3/engine/systems/UpdateSystem.js
@@ -0,0 +1,49 @@
+export class UpdateSystem {
+
+    constructor(application) {
+        this._update = this._update.bind(this);
+        this._render = this._render.bind(this);
+
+        this.application = application;
+        this.running = false;
+    }
+
+    start() {
+        if (this.running) {
+            return;
+        }
+
+        this.application.start?.();
+
+        this._time = performance.now() / 1000;
+
+        this._updateFrame = setInterval(this._update, 0);
+        this._renderFrame = requestAnimationFrame(this._render);
+    }
+
+    stop() {
+        if (!this.running) {
+            return;
+        }
+
+        this.application.stop?.();
+
+        this._updateFrame = clearInterval(this._updateFrame);
+        this._renderFrame = cancelAnimationFrame(this._render);
+    }
+
+    _update() {
+        const time = performance.now() / 1000;
+        const dt = time - this._time;
+        this._time = time;
+
+        this.application.update?.(time, dt);
+    }
+
+    _render() {
+        this._renderFrame = requestAnimationFrame(this._render);
+
+        this.application.render?.();
+    }
+
+}