Blender Git Loki

Bad hack: due to unintelligible linker errors, have to move bf_rna in
front of bf_editor_physics.

For some reason this seems to work for other bf_editor_* libs. Should be
fixed asap, but no working solution is known among core devs, so for now
have to do this to keep working.

RNA for the modifiers list in ParticleSystem and basic UI code.

RNA for particle modifiers.

Operators for adding, removing and moving particle modifiers.

List of particle modifiers in particle systems and read/write code.

Note: Ideally modifiers for particles should be part of the
`ParticleSettings` datablock instead of `ParticleSystem`. The problem
with this is that many modifiers, as they are implemented for meshes,
will store specific data that is associated to the object instance
in the scene. Storing modifiers in the settings would make this
impossible and require some complicated syncing between particle systems
and their settings.

Generalized the low-level `meshdeform_matrix_solve` function to make it
independent from the MeshDeform modifier.

The modifier is just used for error reports here, so can easily be
replaced by a callback.

Simple infrastructure for registering particle modifier types, similar
to type registration of mesh modifiers.

limit autohide distance between 0.0 and 10.0 (mostly very low positive values are used, like 0.001)

Fix some ordering issues, remove leftover glBegin/glEnd

crash fix: changing constraint settings prior to execute fracture caused a crash

Initial VBO code for GPU subsurf.

This commit adds a few generalizations to the VBO
code so that modifiers can create and populate their own GPU objects.

The VBO code originally supported CDDerivedMesh only. The design moves slightly
towards the viewport refactor where the rendering system requests data from the
modifiers.

In this commit only basic support for vertices and normals is provided and
some features from blender's VBO system, suchs as mapping to original faces,
unique element indices for vertices and loose vertex/edge support are missing.
Also, the quick navigation feature of the subsurf modifier won't be supported
for now.

What we do have is full support for solid shading with multiple materials,
flat/smooth shading and a big performance boost.

fix: do not write shards with only 1 vertex, this causes problems when loading the file afterwards, omitting those shards and islands seems not having a negative effect up to now

Use the final hair state also as simulation input/output in hair sim.

Update the world space location of final hair keys after applying
modifiers.

Moved main shapekey evaluation for hair keys from the path caching
function to the new hair modifier evaluation.

This mirrors how shapekeys are treated as a "virtual" modifier at the
beginning of mesh modifier stack eval.

Fix for unfreed duplicated hair key arrays when the number of hair keys
stays the same.

Use the final hair state instead of the initial state for constructing
paths.

Enum for particle system flags instead of old-school #defines.

Reset function for the final hair state before calculating hair dynamics
and paths.

The integration with modifiers is still undefined: While it would be
nicer to have regular modifiers work on hair state as well, it is
probably not feasible with the current particle system, because all
these steps happen in a single update function. For integrating with
the modifier stack we would have to allow splitting this process into
individual parts, which is just not possible.

Added a second hair data layer to store modifier results.

This imitates the DerivedMesh principle from meshes. For hair the
modifiers will get the grooming or original growth result as input.
The result of the modifier eval will be written to the new data layer,
making a simple copy if modifiers are not used. Physics sim, rendering
and (depending of settings) drawing will then use the modified grooming
data.