Blender Git Loki

Better grid rasterization method for hair volumetric grids.

This is based on the paper
"Detail Preserving Continuum Simulation of Straight Hair"
(McAdams, Selle, Ward, 2009)

The main difference is that hair line segments are used rather than only
rasterizing velocity at the vertices. This gives a much better coverage
of the hair volume grid, otherwise gaps can be produced at smaller grid
cell sizes and the distribution is uneven along the hair curve.

The algorithm for rasterizing is a variation of Bresenham's algorithm
extended onto 3D grids.

Depsgraph: Playback doesn't crash now

The time source is expected to be in the root depsgraph node for now,
so we should add it to there instead of the scene node.

This raises some questions:

- Who don't we have Scene ID node in the graph so far?
- Do we really need a time as an operation node, or it's something
more up to the EvaluationContext.

Later one raises the bigger design question: what should we try to
do with the depsgraph and what is we're gonna to solve with the
evaluation context?

The answer here should be: everything which describes the (sub)graph
state should be in the evaluation context. This way this context will
finally become some key which totally corresponds to the (sub)scene
state.

Merge branch 'master' into mesh-transfer-data

Depsgraph: Make update for new frame closer to the master as well

Depsgraph: Remove RNA call to rebuild the DAG

It is now should happen automatically from the scene update,
should be no need in manual tricks now.

Depsgraph: Make scene evaluation closer to the master

This means BKE_scene_update_tagged() will now do the same callbacks and sound
system updates as the old implementation does and will only replace scene update
with new code.

This is aimed to solve the following issues:

- Adding new objects doesn't abort anymore, this is because old code was
rebuilding the depsgraph from the scene update function in cases DAG is NULL.

Don't see why not to do the same with the new dependency graph for now.

- Callbacks are being executed properly, which should make scripts happy.

Well, nobody uses this branch yet, but it's good thing to do and easy to
support anyway.

- Hopefully rendered viewport will be also happier now because the render engine
update is now called for new depsgraph as well.

Merge remote-tracking branch 'origin/master' into depsgraph_refactor

Depsgraph: Solve some compilation issues on my laptop

All the changes seems small but still legit to have so everyone is happy.

fake trigger, disable animated checkbox on collision, (but this should be done by hand, earlier, to get better impact speeds)

Merge branch 'master' into GPencil_EditStrokes

Fix: After using Alt-SelectMouse to select an entire stroke, it would be impossible to select normally again

low- and highres colored smoke

not initializing density fields

SMOKE: mantaflow in Fluid_3d object, running wavelets

Basic, incomplete version of data transfer modifier (WIP).

And some cleanup/fixes/refactor/enhancements found/needed while writing modifier itself.

Add mapping to properties for widgets.

Still pretty much exploring the best way to move here but currently this
works by wrapping objects in RNA pointers, pretty much like buttons do.

Also modified the arrow widget for lamps to use the new code. The new
"unmbrella" widget works now as expected for lamps - of course fine
tuning is also needed.

Depsgraph: Don't use smart templated ID pointer casts

Replace smart templated functions which used to cast ID pointers
with explicit id struct member usage.

This makes code easier to follow and understand what exactly is
going on, don't introduce overhead into code. Plus it's helps
with debugging by skipping entering all that internal template
methods things.

New debug element "circle" for simulations, which is quite useful for
visualizing scalar fields.

Resurrection of 2.49 feature:

Ghosting of original arrow position while we are interacting with an
arrow widget.

Make projection code for arrow widget better. Also add some code to
allow tweaking of properties