oden/game/actor.ts

146 lines
3.1 KiB
TypeScript

import { load_texture } from "./assets";
import { btn, Button } from "./input";
import { Vec2, new_v2, vadd, vnorm, vmul } from "./vector";
import { spr, use_texture, Texture } from "./graphics";
interface ActorSnapshot {
__type__: string;
velocity: Vec2;
friction: number;
id: string;
position: Vec2;
bounds: Vec2;
}
export class Actor {
velocity: Vec2 = new_v2(0);
friction: number = 0.6;
id: string;
position: Vec2;
bounds: Vec2;
constructor(id: string, position: Vec2, bounds: Vec2) {
this.id = id;
this.position = position;
this.bounds = bounds;
}
update() {}
update_physics() {
const velocity = vmul(this.velocity, this.friction);
// Zero if we're smaller than some epsilon.
if (Math.abs(velocity.x) < 0.01) {
velocity.x = 0;
}
if (Math.abs(velocity.y) < 0.01) {
velocity.y = 0;
}
const new_position = vadd(this.position, velocity);
// TODO: Collision detection
// const { w, h } = this.bounds;
this.velocity = velocity;
this.position = new_position;
}
draw(_clock: number) {}
bonk(_other: Actor) {}
snapshot(): ActorSnapshot {
return { ...this, __type__: "??" };
}
assign_snapshot(s: ActorSnapshot) {
this.id = s.id;
this.position = s.position;
this.bounds = s.bounds;
this.velocity = s.velocity;
this.friction = s.friction;
return this;
}
}
const robo_info = {
width: 32,
height: 32,
sprite: "./bot.png",
animations: [
{ start: 0, length: 1, speed: 20 },
{ start: 1, length: 4, speed: 8 },
],
};
interface RoboSnapshot extends ActorSnapshot {
__type__: "robo";
}
export class Robo extends Actor {
bot_sprite: Texture | undefined = undefined;
constructor(pos: Vec2) {
super("robo", pos, new_v2(robo_info.width, robo_info.height));
load_texture(robo_info.sprite).then((texture) => {
this.bot_sprite = texture;
});
}
update() {
// Acceleration from input
let a = new_v2(0);
if (btn(Button.Up)) {
a.y -= 1;
}
if (btn(Button.Down)) {
a.y += 1;
}
if (btn(Button.Left)) {
a.x -= 1;
}
if (btn(Button.Right)) {
a.x += 1;
}
vnorm(a);
this.velocity = vadd(this.velocity, vmul(a, 1.5));
}
draw(clock: number) {
if (this.bot_sprite != undefined) {
use_texture(this.bot_sprite);
const vel = this.velocity;
const moving = vel.x != 0 || vel.y != 0;
const anim = robo_info.animations[moving ? 1 : 0];
const { x: w, y: h } = this.bounds;
const { x, y } = this.position;
const frame = (anim.start + ((clock / anim.speed) % anim.length)) >> 0;
spr(x, y, w, h, frame * w, 0, 32, 32);
}
}
snapshot(): RoboSnapshot {
return { ...super.snapshot(), __type__: "robo" };
}
assign_snapshot(s: RoboSnapshot) {
super.assign_snapshot(s);
return this;
}
}
const SNAPSHOT_TABLE: { [key: string]: (s: any) => Actor } = {
robo: (s: any) => new Robo(new_v2(0)).assign_snapshot(s),
};
export function actor_from_snapshot(s: ActorSnapshot): Actor {
const f = SNAPSHOT_TABLE[s.__type__];
if (f == undefined) {
throw new Error("No handler for " + s.__type__);
}
return f(s);
}