Fallback to gl.canvas.height when gl.canvas.clientHeight are not avai…

[sakitam-fdd]

For #2296

Background

Change List

Fallback to gl.canvas.height when gl.canvas.clientHeight are not available

[CLAassistant]

All committers have signed the CLA.

[1chandu]

This was already fixed here :#2405 , please open an issue with details if you need do make any changes. Closing.

[sakitam-fdd]

@1chandu Yes, I am very happy to see your changes. But I don't think this change is fully functional. In my last test, I found that in addition to the deck.js needs to be rolled back, the draw-layer also needs to be rolled back. So I made this change.

[fuzhenn]

Hi @1chandu ,

#2405 is not enough to fix the off-screen canvas bug described in #2296. getGLViewport will still blank the canvas as it only reads canvas.clientHeight as viewport height which is always 0 when canvas is off-screen. It also needs to fallback to canvas.height when canvas.clientHeight is 0.

As I have tested, this PR will have getGLViewport get the correct viewport height and perfectly fix the off-screen bug, please consider to reopen this PR and have it merged.

Thanks very much!

[fuzhenn]

cc @Pessimistress

[1chandu]

@fuzhenn , this looks good, #2405 missed getGLViewport, I just merged into master.