jumpstorm/engine/systems/Render.ts

51 lines
1.4 KiB
TypeScript

import { System, SystemNames } from '.';
import { BoundingBox, ComponentNames, Sprite } from '../components';
import { Game } from '../Game';
import { clamp } from '../utils';
export class Render extends System {
private ctx: CanvasRenderingContext2D;
constructor(ctx: CanvasRenderingContext2D) {
super(SystemNames.Render);
this.ctx = ctx;
}
public update(dt: number, game: Game) {
this.ctx.clearRect(0, 0, this.ctx.canvas.width, this.ctx.canvas.height);
game.forEachEntityWithComponent(ComponentNames.Sprite, (entity) => {
const sprite = entity.getComponent<Sprite>(ComponentNames.Sprite);
sprite.update(dt);
const boundingBox = entity.getComponent<BoundingBox>(
ComponentNames.BoundingBox
);
// don't render if we're outside the screen
if (
clamp(
boundingBox.center.y,
-boundingBox.dimension.height / 2,
this.ctx.canvas.height + boundingBox.dimension.height / 2
) != boundingBox.center.y ||
clamp(
boundingBox.center.x,
-boundingBox.dimension.width / 2,
this.ctx.canvas.width + boundingBox.dimension.width / 2
) != boundingBox.center.x
) {
return;
}
const drawArgs = {
center: boundingBox.center,
dimension: boundingBox.dimension,
rotation: boundingBox.rotation
};
sprite.draw(this.ctx, drawArgs);
});
}
}