Adding CanvasRenderer support

[RaiNova]

Hello,

I'd like to use react-three-fiber from within a JavaFx WebView, which unfortunately doesn't support WebGL.
For the forseeable future, I don't need really powerful 3D, but I would like to benefit from hardware acceleration, which afaik CanvasRenderer also supports, and from the react concept.

Would this be possible by adding Three.CanvasRenderer support to react-three-fiber? Would anybody else be interested?

Cheers
Rai

[drcmda]

it is supported, every renderer is. here's svgrenderer for instance https://codesandbox.io/s/svg-renderer-zcuqh?file=/src/index.js you can set "gl" for the canvas component as well, in that case you get the real dom canvas as the first argument.

[skuteli]

@drcmda I tried using SVG renderer together with <Canvas/> element, but can't get events to work.
From what I understand the events get attached to the internal <canvas> element and I can't see how I could re-attach them to the <svg> element.

What do you think, maybe we could use gl.domElement instead of explicit <canvas> in <Canvas/> component?
This should help using all the three renderers with <Canvas/>.
On the other hand I'm not really sure what might break so I'd like to know what you think before I'll dive in preparing the PR.

Maybe I'm missing something obvious.
https://codesandbox.io/s/svg-renderer-forked-8xdwt

Use case: Automated testing for cypress or simmilar by swaping renderers in test env and running standard queries from the test library.