Blender Git Loki

Removed unused variable.

Reorganizing hair dynamics UI layout a bit to make settings slightly
more intuitive.

Also removed a couple of unused or useless features from the UI:
* collider friction is unused and replaced in favor of true collision
* spring damping refers to structural springs (stretch), which is
not noticable in hair due to extreme stiffness atm.
* pressure factors are not sure since this feature is too unstable atm.

Unified the main Eigen solver function a bit for constrained/unconstrained
solver variants.

Moved render simplification function for particle distribution into the
distribution code.

Disabled the hair preview feature in the code, due to limited usefulness.

Interpolating hairs in a meaningful way is a quite difficult problem.
It works ok-ish for child hairs as long as they don't move, but with
motion the direction of interpolated hairs can become quite nonsensical
quickly.

Probably a better way to create simulation previews is to limit
simulation to a particular well-defined area (like render preview
borders), but run it in full detail in that area. The error from
omitting some interaction should still be much less than orientation
errors from interpolation.

Updating Eigen implicit dynamics solver implementation to adhere to the
new mass-spring solver API.

Removed unused line.

New hair editing feature "Shape Cut", for cutting hair based on a mesh
shape instead of a brush tool.

The brush cutting tool for hair, while useful, is not very accurate and
often requires rotating the model constantly to get the right trimming
on every side. This makes adjustments to a hair shape a very tedious
process.

On the other hand, making proxy meshes for hair shapes is a common
workflow. The new operator allows using such rough meshes as boundaries
for hair. All hairs that are outside the shape mesh are removed, while
those cutting it at some length are shortened accordingly.

The operator can be accessed in the particle edit mode toolbar via the
"Shape Cut" button. The "Shape Object" must be set first and stays
selected as a tool setting for repeatedly applying the shape.

Switched back to blender implicit solver for merge.

Moved particle code for distributions into own file to make hacking
easier.

This code is badly broken and needs to be replaced, but at least having
a workable code structure might help with quick hacks to fix the worst
cases.

Ported the remaining implicit solver functions for Eigen.

Also added a couple of utility wrapper functions for Eigen types to make
interfacing with plain float arrays and blenlib math easier.

A little bit of code sanity by splitting particle distribution function
by type.

Instead of squashing totally unrelated code into the same monster
function.

Merge branch 'master' into gooseberry

Merge branch 'master' into gooseberry

Conflicts:
source/blender/blenlib/BLI_math_matrix.h
source/blender/blenlib/intern/math_matrix.c
source/blender/editors/object/object_bake_api.c

Reorganizing hair dynamics UI layout a bit to make settings slightly
more intuitive.

Also removed a couple of unused or useless features from the UI:
* collider friction is unused and replaced in favor of true collision
* spring damping refers to structural springs (stretch), which is
not noticable in hair due to extreme stiffness atm.
* pressure factors are not sure since this feature is too unstable atm.

Disabled the hair preview feature in the code, due to limited usefulness.

Interpolating hairs in a meaningful way is a quite difficult problem.
It works ok-ish for child hairs as long as they don't move, but with
motion the direction of interpolated hairs can become quite nonsensical
quickly.

Probably a better way to create simulation previews is to limit
simulation to a particular well-defined area (like render preview
borders), but run it in full detail in that area. The error from
omitting some interaction should still be much less than orientation
errors from interpolation.

Correctly downsample circles of confusion and use parallelism to do it
more efficient.

Second pass, blurs the downsampled buffer once.

Use the correct shaders and varyings

Viewport DOF:

* Scons builds correctly
* Separate vertex shader file for DOF, will make handling main easier
* Downsample color buffer + blur it. Circle of confusion is calculated
from zplane instead of length of distance from camera.