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/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) Blender Foundation
* All rights reserved.
*
* The Original Code is: all of this file.
*
* Contributor(s): Lukas Toenne
*
* ***** END GPL LICENSE BLOCK *****
*/
#ifndef __BPH_IMPLICIT_H__
#define __BPH_IMPLICIT_H__
/** \file implicit.h
* \ingroup bph
*/
#include "stdio.h"
#include "BLI_utildefines.h"
#include "BKE_collision.h"
#ifdef __cplusplus
extern "C" {
#endif
//#define IMPLICIT_SOLVER_EIGEN
#define IMPLICIT_SOLVER_BLENDER
#define CLOTH_ROOT_FRAME /* enable use of root frame coordinate transform */
#define CLOTH_FORCE_GRAVITY
#define CLOTH_FORCE_DRAG
#define CLOTH_FORCE_SPRING_STRUCTURAL
#define CLOTH_FORCE_SPRING_BEND
#define CLOTH_FORCE_SPRING_GOAL
#define CLOTH_FORCE_EFFECTORS
//#define IMPLICIT_PRINT_SOLVER_INPUT_OUTPUT
//#define IMPLICIT_ENABLE_EIGEN_DEBUG
struct Implicit_Data;
struct ImplicitSolverInput;
struct SimDebugData;
typedef struct ImplicitSolverResult {
int status;
int iterations;
float error;
} ImplicitSolverResult;
BLI_INLINE void implicit_print_matrix_elem(float v)
{
printf("%-8.3f", v);
}
/* ==== hash functions for debugging ==== */
BLI_INLINE unsigned int hash_int_2d(unsigned int kx, unsigned int ky)
{
#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
unsigned int a, b, c;
a = b = c = 0xdeadbeef + (2 << 2) + 13;
a += kx;
b += ky;
c ^= b; c -= rot(b,14);
a ^= c; a -= rot(c,11);
b ^= a; b -= rot(a,25);
c ^= b; c -= rot(b,16);
a ^= c; a -= rot(c,4);
b ^= a; b -= rot(a,14);
c ^= b; c -= rot(b,24);
return c;
#undef rot
}
BLI_INLINE int hash_vertex(int type, int vertex)
{
return hash_int_2d((unsigned int)type, (unsigned int)vertex);
}
BLI_INLINE int hash_collpair(int type, CollPair *collpair)
{
return hash_int_2d((unsigned int)type, hash_int_2d((unsigned int)collpair->face1, (unsigned int)collpair->face2));
}
/* ================ */
void BPH_mass_spring_solver_debug_data(struct Implicit_Data *id, struct SimDebugData *debug_data);
void BPH_mass_spring_set_vertex_mass(struct Implicit_Data *data, int index, float mass);
void BPH_mass_spring_set_rest_transform(struct Implicit_Data *data, int index, float rot[3][3]);
void BPH_mass_spring_set_motion_state(struct Implicit_Data *data, int index, const float x[3], const float v[3]);
void BPH_mass_spring_set_position(struct Implicit_Data *data, int index, const float x[3]);
void BPH_mass_spring_set_velocity(struct Implicit_Data *data, int index, const float v[3]);
void BPH_mass_spring_get_motion_state(struct Implicit_Data *data, int index, float x[3], float v[3]);
void BPH_mass_spring_get_position(struct Implicit_Data *data, int index, float x[3]);
/* modified velocity during solver step */
void BPH_mass_spring_get_new_velocity(struct Implicit_Data *data, int index, float v[3]);
void BPH_mass_spring_set_new_velocity(struct Implicit_Data *data, int index, const float v[3]);
void BPH_mass_spring_clear_constraints(struct Implicit_Data *data);
void BPH_mass_spring_add_constraint_ndof0(struct Implicit_Data *data, int index, const float dV[3]);
void BPH_mass_spring_add_constraint_ndof1(struct Implicit_Data *data, int index, const float c1[3], const float c2[3], const float dV[3]);
void BPH_mass_spring_add_constraint_ndof2(struct Implicit_Data *data, int index, const float c1[3], const float dV[3]);
bool BPH_mass_spring_solve_velocities(struct Implicit_Data *data, float dt, struct ImplicitSolverResult *result);
bool BPH_mass_spring_solve_positions(struct Implicit_Data *data, float dt);
void BPH_mass_spring_apply_result(struct Implicit_Data *data);
/* Clear the force vector at the beginning of the time step */
void BPH_mass_spring_clear_forces(struct Implicit_Data *data);
/* Fictitious forces introduced by moving coordinate systems */
void BPH_mass_spring_force_reference_frame(struct Implicit_Data *data, int index, const float acceleration[3], const float omega[3], const float domega_dt[3], float mass);
/* Simple uniform gravity force */
void BPH_mass_spring_force_gravity(struct Implicit_Data *data, int index, float mass, const float g[3]);
/* Global drag force (velocity damping) */
void BPH_mass_spring_force_drag(struct Implicit_Data *data, float drag);
/* Custom external force */
void BPH_mass_spring_force_extern(struct Implicit_Data *data, int i, const float f[3], float dfdx[3][3], float dfdv[3][3]);
/* Wind force, acting on a face */
void BPH_mass_spring_force_face_wind(struct Implicit_Data *data, int v1, int v2, int v3, int v4, const float (*winvec)[3]);
/* Wind force, acting on an edge */
void BPH_mass_spring_force_edge_wind(struct Implicit_Data *data, int v1, int v2, const float (*winvec)[3]);
/* Linear spring force between two points */
bool BPH_mass_spring_force_spring_linear(struct Implicit_Data *data, int i, int j, float restlen,
float stiffness, float damping, bool no_compress, float clamp_force,
float r_f[3], float r_dfdx[3][3], float r_dfdv[3][3]);
/* Bending force, forming a triangle at the base of two structural springs */
bool BPH_mass_spring_force_spring_bending(struct Implicit_Data *data, int i, int j, float restlen,
float kb, float cb,
float r_f[3], float r_dfdx[3][3], float r_dfdv[3][3]);
/* Angular bending force based on local target vectors */
bool BPH_mass_spring_force_spring_bending_angular(struct Implicit_Data *data, int i, int j, int k,
const float target[3], float stiffness, float damping);
/* Global goal spring */
bool BPH_mass_spring_force_spring_goal(struct Implicit_Data *data, int i, const float goal_x[3], const float goal_v[3],
float stiffness, float damping,
float r_f[3], float r_dfdx[3][3], float r_dfdv[3][3]);
/* ======== Hair Volumetric Forces ======== */
struct HairGrid;
struct Object;
struct VoxelData;
struct HairGrid *BPH_hair_volume_create_vertex_grid(int res, const float gmin[3], const float gmax[3]);
void BPH_hair_volume_free_vertex_grid(struct HairGrid *grid);
void BPH_hair_volume_set_debug_data(struct HairGrid *grid, struct SimDebugData *debug_data);
void BPH_hair_volume_grid_geometry(struct HairGrid *grid, float cellsize[3], int res[3], float gmin[3], float gmax[3]);
void BPH_hair_volume_add_vertex(struct HairGrid *grid, const float x[3], const float v[3]);
void BPH_hair_volume_add_segment(struct HairGrid *grid,
const float x1[3], const float v1[3], const float x2[3], const float v2[3],
const float x3[3], const float v3[3], const float x4[3], const float v4[3],
const float dir1[3], const float dir2[3], const float dir3[3]);
void BPH_hair_volume_normalize_vertex_grid(struct HairGrid *grid);
#if 0 /* XXX weighting is incorrect, disabled for now */
void BPH_hair_volume_vertex_grid_filter_box(struct HairVertexGrid *grid, int kernel_size);
#endif
void BPH_hair_volume_grid_interpolate(struct HairGrid *grid, const float x[3],
float *density, float velocity[3], float density_gradient[3], float velocity_gradient[3][3]);
/* Effect of fluid simulation grid on velocities.
* fluid_factor controls blending between PIC (Particle-in-Cell)
* and FLIP (Fluid-Implicit-Particle) methods (0 = only PIC, 1 = only FLIP)
*/
void BPH_hair_volume_grid_velocity(struct HairGrid *grid, const float x[3], const float v[3],
float fluid_factor,
float r_v[3]);
/* XXX Warning: expressing grid effects on velocity as a force is not very stable,
* due to discontinuities in interpolated values!
* Better use hybrid approaches such as described in
* "Detail Preserving Continuum Simulation of Straight Hair"
* (McAdams, Selle 2009)
*/
void BPH_hair_volume_vertex_grid_forces(struct HairGrid *grid, const float x[3], const float v[3],
float smoothfac, float pressurefac, float minpressure,
float f[3], float dfdx[3][3], float dfdv[3][3]);
bool BPH_hair_volume_get_texture_data(struct HairGrid *grid, struct VoxelData *vd);
#ifdef __cplusplus
}
#endif
#endif
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