`onDraw()` receives `const kmMat4 &transform` and `bool
transformUpdated`.
`CC_NODE_DRAW_SETUP()` is no longer used in our code.
`_modelViewTransform` is only used as a cache.
`visit()` and `draw()` are improved.
they both receive:
- `Renderer`
- `kmMat4` for transformation
- `bool` whether or not the transform changed from the previous frame
Although `draw` and `visit` are not using the 3 new parameters,
they will start using it in the coming days (or weeks, or months).
Those parameters are needed for:
- `Renderer` shouldn't be a singleton. There should be one renderer per Director. There could be more than one renderer
- we should get rid of `kmGLXXX` functions since nodoby knows what is happening. the `kmMat4` is for that.
- whenever possible, we should try to optimize the multiplications. the `dirty` flag is for that.
We need those changes, so, it is better to change the API now, and not right after v3.0-final is released.
Could be done in a tighter manner by scheduling updates in
spine::SkeletonAnimation instead and listening for animation events.
However, this may need a more robust interface on scheduleUpdate and
unscheduleUpdate to work correctly.
Ricardo Quesada