Experiment: Render the entire sim in WebGL

[samreid]

In order to estimate an upper bound on performance and provide a way to incrementally add support for WebGL for different node types, I am experimenting with rendering the entire sim in WebGL. Components that do not have a WebGL node can be temporarily rendered as rectangles or equivalent. This issue is to track progress and keep notes on what's been done on this investigation.

[samreid]

I'll create branches in scenery, scenery-phet and fluid-pressure-and-flow called "experimental-webgl-support".

[samreid]

Branches pushed above. Note that SubSupText in scenery-phet was creating new nodes frequently and was causing performance problems during animation. That could be a performance problem in svg/canvas2d as well as webgl.

[samreid]

Here is a version that launches the "flow" screen with WebGL only (and unknown nodes rendered as rectangles). I also converted the flow particles from CanvasNode to regular scenery Rectangles--perhaps they should be converted to WebGLNode?

http://www.colorado.edu/physics/phet/dev/html/fluid-pressure-and-flow/1.0.0-dev.18/fluid-pressure-and-flow_en.html?screens=2

[samreid]

I decided to track this work in scenery, see link above. Closing.