I tried to change it to all the values I found on developer's blogs and even in the Painting the Web Oreily book.
"3d", "-moz-webgl2.0", "webgl2.0", "webgl", "gl", "moz-gles11"
All got me the same NS_ERROR_ILLEGAL_VALUE
// IID for the nsIRenderingContext interface
// 37762dd8-8df0-48cd-a5d6-24573ffdb5b6
#define NS_IRENDERING_CONTEXT_IID \
{ 0x37762dd8, 0x8df0, 0x48cd, \
{ 0xa5, 0xd6, 0x24, 0x57, 0x3f, 0xfd, 0xb5, 0xb6 } }
other example, that also do not work with minefield: http://www.c3dl.org/
Official word: https://wiki.mozilla.org/Canvas:3D
I just got back, and I'm needing to look at the google cache of almost every mozilla forum page; I haven't gotten through to their forums a single time yet.
Their 'search moz code' thingy still works -- searching it for WebGL turns up lots ... I mean LOTS ... of code. But even though I've found a list of enums for contexts, etc, I still haven't quite found where the mapping is, or where the actual base getcontext() function is located.
I have powerful procrastination forces pushing me, though.
Okay, the relevant/revelatory code can be seen at:
http://mxr.mozilla.org/mozilla-central/source/content/html/c...
Here's the string being constructed in the getContext method, after some checking:
nsCString ctxString("@mozilla.org/content/canvas-rendering-context;1?id=");
ctxString.Append(ctxId);
I'd assume it's some kind of resource naming convention or somesuch ... but, anyway, searching for strings "@mozilla.org/" and canvas and gl ...
You get nsLayoutModule.cpp
...
{ "Canvas WebGL Rendering Context",
NS_CANVASRENDERINGCONTEXTWEBGL_CID,
"@mozilla.org/content/canvas-rendering-context;1?id=moz-webgl",
CreateCanvasRenderingContextWebGL },
...
The first example I tried fails:
gl.clearDepth is not a function.
But, anyway, it's a start.