This should be the last place where new arrays were created in "render".

Chrome memory now seems stable.

Firefox still grows like mad, though this used to be like this also with other demos (simply setting random values to existing arrays does this).

Seems like Mozilla folks themselves struggle with this:

http://www.flickr.com/photos/11280278@N04/5363335103/in/photostream/

See discussion here:

https://github.com/mrdoob/three.js/issues#issue/92

For the moment just things that are executed every frame in WebGLRenderer.render.

Continuing with quest to minimize creation of new data structures. Should instead create per class/object structures and just reuse them (as gman does in ThreeD). Main goal is to avoid annoying garbage collection pauses.

Let's hope it didn't break something (could be if some code was dependent on cloning of return values of "flatten" or "makeInvert3x3", though from what I checked these are just used to set typed arrays uniforms).

Also doesn't seem to decrease performance so far (though most of demos have small number of objects).

Testing on current examples didn't show any noticeable performance degradation when enabling / disabling culling for every object in every frame.

"FlipSided" property could be probably done in very similar way, just setting "gl.frontFace( gl.CCW )" or "gl.frontFace( gl.CW )"

Alternating convolution pass textures aspect ratio and using linear magnification filtering leads to less artefacts.

For this had to extend WebGLRenderer a bit:

- MeshShaderMaterial now can take non-specific float array uniforms as "fv1"
  (there is already "fv" type for array of 3-item-vectors, which probably should be renamed to "fv3" to be consistent)

- render method has yet another parameter "clear" for clearing newly set framebuffer (defaults to true).
  This is a bit hackish but it seems necessary to control this somehow. I didn't manage to replicate
  desired behavior just with autoClear.

- another dirty thing is accessing GL context from the application side:
    renderer.context.disable( renderer.context.DEPTH_TEST );

    This should be refactored somehow, wrapped in some API call.

Requires to turn off mipmapping to be able to use non-power of two texture.

Effect of texture size on performance is noticeable, also there is no antialiasing (default in Chrome is I think 4x multisampling).

So I guess full-screen postprocessing will be quite costly :(. That's the price of WebGL always running at full-blown high resolution.

This could be somehow mitigated by faking lower resolutions via smaller texture, though I guess it still wouldn't be the same as having lower resolution set by GPU driver (this is a major help with performance in games - I never run full 1680 x 1050).

Rendering proper 3d object into the texture uncovered another issue - framebuffer had to be cleared after switching.

Texture is still flipped :( (original scene has small red torus on the top)

This is proving to be rather tricky. Yet again I tried to handle image coordinate mess in a proper way (UNPACK_FLIP_Y_WEBGL as texture parameter and non-inverted UVs), fixing hacks across the codebase.

This did indeed help with render-to-texture flipping, but instead it created really ugly problems with both normal map and minecraft AO demos. So back to square one :(

Still flipped, though at least now it's consistent.

Had to set viewport to make it work in OpenGL.

Also made it easier to see texture orientation in the example.

Now it's visible that there is indeed flipping. At least now it's consistent ;).

Something is broken as OpenGL shows different result than ANGLE :(

Though this time it's ANGLE which seems correct.

This is untested, as example is in different branch, have to commit this merge first.

At least this didn't seem to break existing things.

Added dynamic geometry support also for WebGL lines. Changed line strip example to use Hilbert curves.

Also fixed tons of bugs in lines handling.

TODO: make some example for dynamic lines.

If you want to refresh VBOs (and thus have geometry changes reflected in renderer), you need to set dirty flags on geometry object.

There are separate flags for different buffers (as not always all buffers need to be updated and oh my is updating costly):

    mesh.geometry.__dirtyVertices = true;
    mesh.geometry.__dirtyNormals = true;
    mesh.geometry.__dirtyUvs = true;
    mesh.geometry.__dirtyTangents = true;

    mesh.geometry.__dirtyElements = true;

That was quite tough feature, a lot of refactoring, yet performance is still quite bad :(

The biggest remaining bottleneck seems to be translation between Three.js internal data formats and buffers. I removed as much per-frame arrays creation as I could, but even just iterating through existing data and setting of values is still very costly. Also per-frame normals computation is expensive.

Also some refactoring of initWebGLObjects slipped in this commit.

No need to stuff them in different bucket, line-specific stuff is anyway done in `renderBuffer` method.

This was prompted by starting with implementation of ParticleSystem. It would be unwieldy to handle three different buckets of objects / buffers.