Changes from 3.1-3 to 3.2-1
1. Local space simulation
A. Each hair solver can switch between local/world space simulation mode
B. Typical use case – in case of abrupt linear/angular speed change or fast rotating motions, the hair simulation can be unstable or undesirable due to excessive inertial effects or erroneous collision handling. By using local space simulation, such artifacts can be greatly reduced by explicitly controlling the inertial effects.
C. Usage
i. Step 1: For a solver which has multiple hair systems, first check if the output curve groups of each hair system have identical transformation matrices.
ii. Step 2: Choose or create a transform node that will act as the reference transform (for example, constrain an object to a face or a vertex of the base mesh using “Constrain>Point on Poly” command)
iii. Step 3: Parent the output curve groups to the selected reference transform node which follows the base mesh motion
iv. Step 4: Select a hair solver, or a hair system under the solver, and click “FXHair>Set Local Space Simulation”. To undo this, select a solver and click “FXHair>Set World Space Simulation” (Note that local space simulation is performed per solver, not a hair system, even though the inertial effects can be scaled differently per hair system as described below)
D. Inertial effect control
i. The solver and the hair system have following four scale parameters for each inertial
effect. The scale parameters of each hair system are multiplied by the solver’s corresponding parameters before application.
1. Linear Velocity Scale – affects the air drag force caused by the linear movement of the reference transform
2. Linear Acceleration Scale – affects linear inertial effect caused by the linear acceleration of the reference transform
3. Angular Velocity Scale – affects (1) centrifugal force, (2) Coriolis force, and (3) air drag force caused by the angular motion of the reference transform
4. Angular Acceleration Scale – affects Euler force caused by the angular acceleration of the reference transform
ii. Each of the above four parameters can be larger than 1.0, or even can be negative. Typical range would be 0.0~5.0
2. hrHairSystem added the attribute “Interaction Depth Color”
A. Users can change the color of the visualized interaction depth for each hair system
3. Default curve sampling method is changed to “Match CV” from “Uniform”
4. “FXHair>Show/Hide XXX Curves” now works for all the selected hair systems and/or solvers
5. Bug fixes
A. When a hair system has cached data and other hair systems under the same solver have no cache data, the maya crashes when re-opened and the time slider is not set at the start frame of the solver. This bug is fixed
B. When an attach constraint has invalid CV indices, Maya crashes when re-opened. This bug is fixed.