fix: [#3234] Expose ex.RendererPlugin type to devs

closes: #3234

CHANGELOG.md

@@ -105,6 +105,7 @@ are doing mtv adjustments during precollision.
 
 ### Fixed
 
+- Fixed issue where users could not easily define a custom `RendererPlugin` because the type was not exposed
 - Fixed issue where `ex.Fade` sometimes would not complete depending on the elapsed time
 - Fixed issue where `ex.PolygonColliders` would get trapped in infinite loop for degenerate polygons (< 3 vertices)
 - Fixed issue where certain devices that support large numbers of texture slots exhaust the maximum number of if statements (complexity) in the shader.

sandbox/src/game.ts

@@ -109,13 +109,38 @@ game.currentScene.onPreDraw = (ctx: ex.ExcaliburGraphicsContext) => {
   bb.right--;
   bb.draw(ctx, ex.Color.Yellow);
 
+  // (ctx as ex.ExcaliburGraphicsContextWebGL).draw('custom', 1, 2, 3, 'custom args');
+
   ctx.drawCircle(ex.vec(bb.left + 6, bb.top + 6), 10, green);
   ctx.drawCircle(ex.vec(bb.right - 6, bb.top + 6), 10, blue);
   ctx.drawCircle(ex.vec(bb.left + 6, bb.bottom - 6), 10, yellow);
   ctx.drawCircle(ex.vec(bb.right - 6, bb.bottom - 6), 10, red);
   ctx.restore();
 };
 
+class CustomRenderer implements ex.RendererPlugin {
+  type = 'custom';
+  priority = 99;
+  initialize(gl: WebGL2RenderingContext, context: ex.ExcaliburGraphicsContextWebGL): void {
+    console.log('custom init');
+  }
+  draw(...args: any[]): void {
+    console.log('custom draw', ...args);
+  }
+  hasPendingDraws(): boolean {
+    return false;
+  }
+  flush(): void {
+    // pass
+  }
+  dispose(): void {
+    // pass
+  }
+}
+const customRenderer = new CustomRenderer();
+
+(game.graphicsContext as ex.ExcaliburGraphicsContextWebGL).register(customRenderer);
+
 game.on('fallbackgraphicscontext', (ctx) => {
   console.log('fallback triggered', ctx);
 });

src/engine/Graphics/index.ts

@@ -48,6 +48,7 @@ export * from './Context/vertex-buffer';
 export * from './Context/vertex-layout';
 export * from './Context/quad-index-buffer';
 export * from './Context/material';
+export * from './Context/renderer';
 
 // Debug
 export * from './Debug';