fix: [#2854] Actor pre/post draw events fixed (#2860)

Closes #2854

CHANGELOG.md

@@ -25,6 +25,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 
+- Fixed Actor so it receives `predraw`/`postdraw` events per the advertised strongly typed events
 - Fixed infinite loop :bomb: when certain degenerate polygons were attempted to be triangulated!
 - Fixed incorrect type on `ex.Tilemap.getTileByPoint()`
 - Fixed TS type on `GraphicsComponent` and allow `.material` to be null to unset, current workaround is using `.material = null as any`

src/engine/Graphics/GraphicsSystem.ts

@@ -13,6 +13,7 @@ import { ParallaxComponent } from './ParallaxComponent';
 import { CoordPlane } from '../Math/coord-plane';
 import { BodyComponent } from '../Collision/BodyComponent';
 import { FontCache } from './FontCache';
+import { PostDrawEvent, PreDrawEvent } from '..';
 
 export class GraphicsSystem extends System<TransformComponent | GraphicsComponent> {
   public readonly types = ['ex.transform', 'ex.graphics'] as const;
@@ -126,6 +127,7 @@ export class GraphicsSystem extends System<TransformComponent | GraphicsComponen
       if (graphics.onPreDraw) {
         graphics.onPreDraw(this._graphicsContext, delta);
       }
+      entity.events.emit('predraw', new PreDrawEvent(this._graphicsContext, delta, entity));
 
       // TODO remove this hack on the particle redo
       const particleOpacity = (entity instanceof Particle) ? entity.opacity : 1;
@@ -138,6 +140,7 @@ export class GraphicsSystem extends System<TransformComponent | GraphicsComponen
       if (graphics.onPostDraw) {
         graphics.onPostDraw(this._graphicsContext, delta);
       }
+      entity.events.emit('postdraw', new PostDrawEvent(this._graphicsContext, delta, entity));
 
       this._graphicsContext.restore();
 

src/spec/ActorSpec.ts

@@ -839,6 +839,28 @@ describe('A game actor', () => {
     expect(animation.tick).toHaveBeenCalledWith(100, 2);
   });
 
+  it('will receive predraw/postdraw', () => {
+    const predraw = jasmine.createSpy('predraw');
+    const postdraw = jasmine.createSpy('postdraw');
+
+    const actor = new ex.Actor({
+      name: 'events',
+      pos: ex.vec(100, 100),
+      width: 100,
+      height: 100,
+      color: ex.Color.Red
+    });
+
+    actor.events.on('predraw', predraw);
+    actor.events.on('postdraw', postdraw);
+
+    scene.add(actor);
+    scene.draw(engine.graphicsContext, 100);
+
+    expect(predraw).toHaveBeenCalledOnceWith(new ex.PreDrawEvent(engine.graphicsContext, 100, actor));
+    expect(postdraw).toHaveBeenCalledOnceWith(new ex.PostDrawEvent(engine.graphicsContext, 100, actor));
+  });
+
   it('can detect containment off of child actors', () => {
     const parent = new ex.Actor({ x: 600, y: 100, width: 100, height: 100 });
     const child = new ex.Actor({ x: 0, y: 0, width: 100, height: 100 });