TODO

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/*                    TO DO                   */
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Check on Debug FPS:
    - Seems off?

Sprite Shader:
    - Improve ImageLoader / Assets.images:
    - Sprite class:

Polygons:
    - Chipmunk Debug Draw, https://github.com/slembcke/Chipmunk2D/blob/master/demo/ChipmunkDebugDraw.c
    - Two.js, https://two.js.org/

Program Management:
    - Shader Chunks

Uber Shader:
    - lighting

Geometry Utility Functions (GeomUtils):
    - mergeGeometries()
    - toJson()

Context Lost:
    - Do something about global 'window.renderer.gl', need to handle multiple renderers / gl contexts
      - Continue in Renderer.initContext()

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/*          ENGINE OPTIMIZATION IDEAS         */
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WebGL Reference:
    - ogl (current with 03/21/23), three, picogl, redgl, twgl, webglfundamentals

Optimization:
    - General:
        - Low end gpus, limit to < 2 million triangles, < 400 draw calls per frame
    - Limit Sorting:
        - Dual depth peeling
            https://github.com/tsherif/webgl2examples/blob/master/oit-dual-depth-peeling.html
        - Weighted, blended order independent transparency
            https://github.com/tsherif/webgl2examples/blob/master/oit.html
            https://github.com/stevinz/three-wboit
    - Reduce Draw Calls:
        - Instancing
        - Scene geometry baking / geometry merging
            - THREE.BufferGeometryUtils.mergeGeometries()
                https://github.com/mrdoob/three.js/blob/de7c36a30773aa7941c46516af71e6993a7640ea/examples/jsm/utils/BufferGeometryUtils.js#L113
        - Occlusion culling
            https://github.com/tsherif/webgl2examples/blob/master/occlusion.html
    - Reduce State Changes:
        - Uniform Blocks
            https://subscription.packtpub.com/book/game-development/9781782167020/1/ch01lvl1sec18/using-uniform-blocks-and-uniform-buffer-objects
    - Speed Lighting:
        - Deferred / Forward+ Rendering
            https://github.com/tsherif/webgl2examples/blob/master/deferred.html
              https://learnopengl.com/Advanced-Lighting/Deferred-Shading
            https://gamedevelopment.tutsplus.com/articles/forward-rendering-vs-deferred-rendering--gamedev-12342
              https://docs.unity3d.com/Packages/com.unity.render-pipelines.high-definition@6.5/manual/Forward-And-Deferred-Rendering.html
            https://discourse.threejs.org/t/dr-strangelight-or-how-i-learned-to-stop-worrying-and-love-the-cluster/23104

Nanite:
    - Nexus (js nanite):
        http://vcg.isti.cnr.it/nexus/#nexus.js
        https://github.com/cnr-isti-vclab/nexus
    - Corto (compression):
        http://vcg.isti.cnr.it/corto/index.html
        https://github.com/cnr-isti-vclab/corto