tornavis/source/blender/blenkernel/intern/mball_tessellate.cc

1500 lines
40 KiB
C++

/* SPDX-FileCopyrightText: 2001-2002 NaN Holding BV. All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup bke
*/
#include <cctype>
#include <cfloat>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include "MEM_guardedalloc.h"
#include "DNA_mesh_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_meta_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "BLI_listbase.h"
#include "BLI_math_geom.h"
#include "BLI_math_matrix.h"
#include "BLI_math_rotation.h"
#include "BLI_math_vector.h"
#include "BLI_memarena.h"
#include "BLI_string_utils.hh"
#include "BLI_utildefines.h"
#include "BKE_displist.h"
#include "BKE_global.h"
#include "BKE_lib_id.h"
#include "BKE_mball_tessellate.h" /* own include */
#include "BKE_mesh.hh"
#include "BKE_object.hh"
#include "BKE_scene.h"
#include "DEG_depsgraph.hh"
#include "DEG_depsgraph_query.hh"
#include "BLI_strict_flags.h"
/* experimental (faster) normal calculation (see #103021) */
#define USE_ACCUM_NORMAL
#define MBALL_ARRAY_LEN_INIT 4096
/* Data types */
/** Corner of a cube. */
struct CORNER {
int i, j, k; /* (i, j, k) is index within lattice */
float co[3], value; /* location and function value */
CORNER *next;
};
/** Partitioning cell (cube). */
struct CUBE {
int i, j, k; /* lattice location of cube */
CORNER *corners[8]; /* eight corners */
};
/** Linked list of cubes acting as stack. */
struct CUBES {
CUBE cube; /* a single cube */
CUBES *next; /* remaining elements */
};
/** List of cube locations. */
struct CENTERLIST {
int i, j, k; /* cube location */
CENTERLIST *next; /* remaining elements */
};
/** List of edges. */
struct EDGELIST {
int i1, j1, k1, i2, j2, k2; /* edge corner ids */
int vid; /* vertex id */
EDGELIST *next; /* remaining elements */
};
/** List of integers. */
struct INTLIST {
int i; /* an integer */
INTLIST *next; /* remaining elements */
};
/** List of list of integers. */
struct INTLISTS {
INTLIST *list; /* a list of integers */
INTLISTS *next; /* remaining elements */
};
/** An AABB with pointer to metal-elem. */
struct Box {
float min[3], max[3];
const MetaElem *ml;
};
struct MetaballBVHNode { /* node */
Box bb[2]; /* AABB of children */
MetaballBVHNode *child[2];
};
/** Parameters, storage. */
struct PROCESS {
float thresh, size; /* mball threshold, single cube size */
float delta; /* small delta for calculating normals */
uint converge_res; /* converge procedure resolution (more = slower) */
MetaElem **mainb; /* array of all meta-elems. */
uint totelem, mem; /* number of meta-elems. */
MetaballBVHNode metaball_bvh; /* The simplest bvh */
Box allbb; /* Bounding box of all meta-elems */
MetaballBVHNode **bvh_queue; /* Queue used during bvh traversal */
uint bvh_queue_size;
CUBES *cubes; /* stack of cubes waiting for polygonization */
CENTERLIST **centers; /* cube center hash table */
CORNER **corners; /* corner value hash table */
EDGELIST **edges; /* edge and vertex id hash table */
int (*indices)[4]; /* output indices */
uint totindex; /* size of memory allocated for indices */
uint curindex; /* number of currently added indices */
blender::Vector<blender::float3> co; /* surface vertices positions */
blender::Vector<blender::float3> no; /* surface vertex normals */
/* memory allocation from common pool */
MemArena *pgn_elements;
};
/* Forward declarations */
static int vertid(PROCESS *process, const CORNER *c1, const CORNER *c2);
static void add_cube(PROCESS *process, int i, int j, int k);
static void make_face(PROCESS *process, int i1, int i2, int i3, int i4);
static void converge(PROCESS *process, const CORNER *c1, const CORNER *c2, float r_p[3]);
/* ******************* SIMPLE BVH ********************* */
static void make_box_union(const BoundBox *a, const Box *b, Box *r_out)
{
r_out->min[0] = min_ff(a->vec[0][0], b->min[0]);
r_out->min[1] = min_ff(a->vec[0][1], b->min[1]);
r_out->min[2] = min_ff(a->vec[0][2], b->min[2]);
r_out->max[0] = max_ff(a->vec[6][0], b->max[0]);
r_out->max[1] = max_ff(a->vec[6][1], b->max[1]);
r_out->max[2] = max_ff(a->vec[6][2], b->max[2]);
}
static void make_box_from_metaelem(Box *r, const MetaElem *ml)
{
copy_v3_v3(r->max, ml->bb->vec[6]);
copy_v3_v3(r->min, ml->bb->vec[0]);
r->ml = ml;
}
/**
* Partitions part of #process.mainb array [start, end) along axis s. Returns i,
* where centroids of elements in the [start, i) segment lie "on the right side" of div,
* and elements in the [i, end) segment lie "on the left"
*/
static uint partition_mainb(MetaElem **mainb, uint start, uint end, uint s, float div)
{
uint i = start, j = end - 1;
div *= 2.0f;
while (true) {
while (i < j && div > (mainb[i]->bb->vec[6][s] + mainb[i]->bb->vec[0][s])) {
i++;
}
while (j > i && div < (mainb[j]->bb->vec[6][s] + mainb[j]->bb->vec[0][s])) {
j--;
}
if (i >= j) {
break;
}
std::swap(mainb[i], mainb[j]);
i++;
j--;
}
if (i == start) {
i++;
}
return i;
}
/**
* Recursively builds a BVH, dividing elements along the middle of the longest axis of allbox.
*/
static void build_bvh_spatial(
PROCESS *process, MetaballBVHNode *node, uint start, uint end, const Box *allbox)
{
uint part, j, s;
float dim[3], div;
/* Maximum bvh queue size is number of nodes which are made, equals calls to this function. */
process->bvh_queue_size++;
dim[0] = allbox->max[0] - allbox->min[0];
dim[1] = allbox->max[1] - allbox->min[1];
dim[2] = allbox->max[2] - allbox->min[2];
s = 0;
if (dim[1] > dim[0] && dim[1] > dim[2]) {
s = 1;
}
else if (dim[2] > dim[1] && dim[2] > dim[0]) {
s = 2;
}
div = allbox->min[s] + (dim[s] / 2.0f);
part = partition_mainb(process->mainb, start, end, s, div);
make_box_from_metaelem(&node->bb[0], process->mainb[start]);
node->child[0] = nullptr;
if (part > start + 1) {
for (j = start; j < part; j++) {
make_box_union(process->mainb[j]->bb, &node->bb[0], &node->bb[0]);
}
node->child[0] = static_cast<MetaballBVHNode *>(
BLI_memarena_alloc(process->pgn_elements, sizeof(MetaballBVHNode)));
build_bvh_spatial(process, node->child[0], start, part, &node->bb[0]);
}
node->child[1] = nullptr;
if (part < end) {
make_box_from_metaelem(&node->bb[1], process->mainb[part]);
if (part < end - 1) {
for (j = part; j < end; j++) {
make_box_union(process->mainb[j]->bb, &node->bb[1], &node->bb[1]);
}
node->child[1] = static_cast<MetaballBVHNode *>(
BLI_memarena_alloc(process->pgn_elements, sizeof(MetaballBVHNode)));
build_bvh_spatial(process, node->child[1], part, end, &node->bb[1]);
}
}
else {
INIT_MINMAX(node->bb[1].min, node->bb[1].max);
}
}
/* ******************** ARITH ************************* */
/**
* BASED AT CODE (but mostly rewritten) :
* C code from the article
* "An Implicit Surface Polygonizer"
* by Jules Bloomenthal <jbloom@beauty.gmu.edu>
* in "Graphics Gems IV", Academic Press, 1994
*
* Authored by Jules Bloomenthal, Xerox PARC.
* Copyright (c) Xerox Corporation, 1991. All rights reserved.
* Permission is granted to reproduce, use and distribute this code for
* any and all purposes, provided that this notice appears in all copies.
*/
#define L 0 /* Left direction: -x, -i. */
#define R 1 /* Right direction: +x, +i. */
#define B 2 /* Bottom direction: -y, -j. */
#define T 3 /* Top direction: +y, +j. */
#define N 4 /* Near direction: -z, -k. */
#define F 5 /* Far direction: +z, +k. */
#define LBN 0 /* Left bottom near corner. */
#define LBF 1 /* Left bottom far corner. */
#define LTN 2 /* Left top near corner. */
#define LTF 3 /* Left top far corner. */
#define RBN 4 /* Right bottom near corner. */
#define RBF 5 /* Right bottom far corner. */
#define RTN 6 /* Right top near corner. */
#define RTF 7 /* Right top far corner. */
/**
* the LBN corner of cube (i, j, k), corresponds with location
* (i-0.5)*size, (j-0.5)*size, (k-0.5)*size)
*/
#define HASHBIT (5)
/** Hash table size (32768). */
#define HASHSIZE size_t(1 << (3 * HASHBIT))
#define HASH(i, j, k) ((((((i)&31) << 5) | ((j)&31)) << 5) | ((k)&31))
#define MB_BIT(i, bit) (((i) >> (bit)) & 1)
// #define FLIP(i, bit) ((i) ^ 1 << (bit)) /* flip the given bit of i */
/* ******************** DENSITY COPMPUTATION ********************* */
/**
* Computes density from given metaball at given position.
* Metaball equation is: `(1 - r^2 / R^2)^3 * s`
*
* r = distance from center
* R = metaball radius
* s - metaball stiffness
*/
static float densfunc(const MetaElem *ball, float x, float y, float z)
{
float dist2;
float dvec[3] = {x, y, z};
mul_m4_v3((const float(*)[4])ball->imat, dvec);
switch (ball->type) {
case MB_BALL:
/* do nothing */
break;
case MB_CUBE:
if (dvec[2] > ball->expz) {
dvec[2] -= ball->expz;
}
else if (dvec[2] < -ball->expz) {
dvec[2] += ball->expz;
}
else {
dvec[2] = 0.0;
}
ATTR_FALLTHROUGH;
case MB_PLANE:
if (dvec[1] > ball->expy) {
dvec[1] -= ball->expy;
}
else if (dvec[1] < -ball->expy) {
dvec[1] += ball->expy;
}
else {
dvec[1] = 0.0;
}
ATTR_FALLTHROUGH;
case MB_TUBE:
if (dvec[0] > ball->expx) {
dvec[0] -= ball->expx;
}
else if (dvec[0] < -ball->expx) {
dvec[0] += ball->expx;
}
else {
dvec[0] = 0.0;
}
break;
case MB_ELIPSOID:
dvec[0] /= ball->expx;
dvec[1] /= ball->expy;
dvec[2] /= ball->expz;
break;
/* *** deprecated, could be removed?, do-versioned at least *** */
case MB_TUBEX:
if (dvec[0] > ball->len) {
dvec[0] -= ball->len;
}
else if (dvec[0] < -ball->len) {
dvec[0] += ball->len;
}
else {
dvec[0] = 0.0;
}
break;
case MB_TUBEY:
if (dvec[1] > ball->len) {
dvec[1] -= ball->len;
}
else if (dvec[1] < -ball->len) {
dvec[1] += ball->len;
}
else {
dvec[1] = 0.0;
}
break;
case MB_TUBEZ:
if (dvec[2] > ball->len) {
dvec[2] -= ball->len;
}
else if (dvec[2] < -ball->len) {
dvec[2] += ball->len;
}
else {
dvec[2] = 0.0;
}
break;
/* *** end deprecated *** */
}
/* ball->rad2 is inverse of squared rad */
dist2 = 1.0f - (len_squared_v3(dvec) * ball->rad2);
/* ball->s is negative if metaball is negative */
return (dist2 < 0.0f) ? 0.0f : (ball->s * dist2 * dist2 * dist2);
}
/**
* Computes density at given position form all meta-balls which contain this point in their box.
* Traverses BVH using a queue.
*/
static float metaball(PROCESS *process, float x, float y, float z)
{
float dens = 0.0f;
uint front = 0, back = 0;
MetaballBVHNode *node;
process->bvh_queue[front++] = &process->metaball_bvh;
while (front != back) {
node = process->bvh_queue[back++];
for (int i = 0; i < 2; i++) {
if ((node->bb[i].min[0] <= x) && (node->bb[i].max[0] >= x) && (node->bb[i].min[1] <= y) &&
(node->bb[i].max[1] >= y) && (node->bb[i].min[2] <= z) && (node->bb[i].max[2] >= z))
{
if (node->child[i]) {
process->bvh_queue[front++] = node->child[i];
}
else {
dens += densfunc(node->bb[i].ml, x, y, z);
}
}
}
}
return process->thresh - dens;
}
/**
* Adds face to indices, expands memory if needed.
*/
static void make_face(PROCESS *process, int i1, int i2, int i3, int i4)
{
#ifdef USE_ACCUM_NORMAL
float n[3];
#endif
if (UNLIKELY(process->totindex == process->curindex)) {
process->totindex = process->totindex ? (process->totindex * 2) : MBALL_ARRAY_LEN_INIT;
process->indices = static_cast<int(*)[4]>(
MEM_reallocN(process->indices, sizeof(int[4]) * process->totindex));
}
int *cur = process->indices[process->curindex++];
/* Treat triangles as fake quads. */
cur[0] = i1;
cur[1] = i2;
cur[2] = i3;
cur[3] = i4;
#ifdef USE_ACCUM_NORMAL
if (i4 == i3) {
normal_tri_v3(n, process->co[i1], process->co[i2], process->co[i3]);
accumulate_vertex_normals_v3(process->no[i1],
process->no[i2],
process->no[i3],
nullptr,
n,
process->co[i1],
process->co[i2],
process->co[i3],
nullptr);
}
else {
normal_quad_v3(n, process->co[i1], process->co[i2], process->co[i3], process->co[i4]);
accumulate_vertex_normals_v3(process->no[i1],
process->no[i2],
process->no[i3],
process->no[i4],
n,
process->co[i1],
process->co[i2],
process->co[i3],
process->co[i4]);
}
#endif
}
/* Frees allocated memory */
static void freepolygonize(PROCESS *process)
{
if (process->corners) {
MEM_freeN(process->corners);
}
if (process->edges) {
MEM_freeN(process->edges);
}
if (process->centers) {
MEM_freeN(process->centers);
}
if (process->mainb) {
MEM_freeN(process->mainb);
}
if (process->bvh_queue) {
MEM_freeN(process->bvh_queue);
}
if (process->pgn_elements) {
BLI_memarena_free(process->pgn_elements);
}
}
/* **************** POLYGONIZATION ************************ */
/**** Cubical Polygonization (optional) ****/
#define LB 0 /* left bottom edge */
#define LT 1 /* left top edge */
#define LN 2 /* left near edge */
#define LF 3 /* left far edge */
#define RB 4 /* right bottom edge */
#define RT 5 /* right top edge */
#define RN 6 /* right near edge */
#define RF 7 /* right far edge */
#define BN 8 /* bottom near edge */
#define BF 9 /* bottom far edge */
#define TN 10 /* top near edge */
#define TF 11 /* top far edge */
static INTLISTS *cubetable[256];
static char faces[256];
/* edge: LB, LT, LN, LF, RB, RT, RN, RF, BN, BF, TN, TF */
static int corner1[12] = {
LBN,
LTN,
LBN,
LBF,
RBN,
RTN,
RBN,
RBF,
LBN,
LBF,
LTN,
LTF,
};
static int corner2[12] = {
LBF,
LTF,
LTN,
LTF,
RBF,
RTF,
RTN,
RTF,
RBN,
RBF,
RTN,
RTF,
};
static int leftface[12] = {
B,
L,
L,
F,
R,
T,
N,
R,
N,
B,
T,
F,
};
/* face on left when going corner1 to corner2 */
static int rightface[12] = {
L,
T,
N,
L,
B,
R,
R,
F,
B,
F,
N,
T,
};
/* face on right when going corner1 to corner2 */
/**
* triangulate the cube directly, without decomposition
*/
static void docube(PROCESS *process, CUBE *cube)
{
INTLISTS *polys;
CORNER *c1, *c2;
int i, index = 0, count, indexar[8];
/* Determine which case cube falls into. */
for (i = 0; i < 8; i++) {
if (cube->corners[i]->value > 0.0f) {
index += (1 << i);
}
}
/* Using faces[] table, adds neighboring cube if surface intersects face in this direction. */
if (MB_BIT(faces[index], 0)) {
add_cube(process, cube->i - 1, cube->j, cube->k);
}
if (MB_BIT(faces[index], 1)) {
add_cube(process, cube->i + 1, cube->j, cube->k);
}
if (MB_BIT(faces[index], 2)) {
add_cube(process, cube->i, cube->j - 1, cube->k);
}
if (MB_BIT(faces[index], 3)) {
add_cube(process, cube->i, cube->j + 1, cube->k);
}
if (MB_BIT(faces[index], 4)) {
add_cube(process, cube->i, cube->j, cube->k - 1);
}
if (MB_BIT(faces[index], 5)) {
add_cube(process, cube->i, cube->j, cube->k + 1);
}
/* Using cubetable[], determines polygons for output. */
for (polys = cubetable[index]; polys; polys = polys->next) {
INTLIST *edges;
count = 0;
/* Sets needed vertex id's lying on the edges. */
for (edges = polys->list; edges; edges = edges->next) {
c1 = cube->corners[corner1[edges->i]];
c2 = cube->corners[corner2[edges->i]];
indexar[count] = vertid(process, c1, c2);
count++;
}
/* Adds faces to output. */
if (count > 2) {
switch (count) {
case 3:
make_face(process, indexar[2], indexar[1], indexar[0], indexar[0]); /* triangle */
break;
case 4:
make_face(process, indexar[3], indexar[2], indexar[1], indexar[0]);
break;
case 5:
make_face(process, indexar[3], indexar[2], indexar[1], indexar[0]);
make_face(process, indexar[4], indexar[3], indexar[0], indexar[0]); /* triangle */
break;
case 6:
make_face(process, indexar[3], indexar[2], indexar[1], indexar[0]);
make_face(process, indexar[5], indexar[4], indexar[3], indexar[0]);
break;
case 7:
make_face(process, indexar[3], indexar[2], indexar[1], indexar[0]);
make_face(process, indexar[5], indexar[4], indexar[3], indexar[0]);
make_face(process, indexar[6], indexar[5], indexar[0], indexar[0]); /* triangle */
break;
}
}
}
}
/**
* return corner with the given lattice location
* set (and cache) its function value
*/
static CORNER *setcorner(PROCESS *process, int i, int j, int k)
{
/* for speed, do corner value caching here */
CORNER *c;
int index;
/* does corner exist? */
index = HASH(i, j, k);
c = process->corners[index];
for (; c != nullptr; c = c->next) {
if (c->i == i && c->j == j && c->k == k) {
return c;
}
}
c = static_cast<CORNER *>(BLI_memarena_alloc(process->pgn_elements, sizeof(CORNER)));
c->i = i;
c->co[0] = (float(i) - 0.5f) * process->size;
c->j = j;
c->co[1] = (float(j) - 0.5f) * process->size;
c->k = k;
c->co[2] = (float(k) - 0.5f) * process->size;
c->value = metaball(process, c->co[0], c->co[1], c->co[2]);
c->next = process->corners[index];
process->corners[index] = c;
return c;
}
/**
* return next clockwise edge from given edge around given face
*/
static int nextcwedge(int edge, int face)
{
switch (edge) {
case LB:
return (face == L) ? LF : BN;
case LT:
return (face == L) ? LN : TF;
case LN:
return (face == L) ? LB : TN;
case LF:
return (face == L) ? LT : BF;
case RB:
return (face == R) ? RN : BF;
case RT:
return (face == R) ? RF : TN;
case RN:
return (face == R) ? RT : BN;
case RF:
return (face == R) ? RB : TF;
case BN:
return (face == B) ? RB : LN;
case BF:
return (face == B) ? LB : RF;
case TN:
return (face == T) ? LT : RN;
case TF:
return (face == T) ? RT : LF;
}
return 0;
}
/**
* \return the face adjoining edge that is not the given face
*/
static int otherface(int edge, int face)
{
int other = leftface[edge];
return face == other ? rightface[edge] : other;
}
/**
* create the 256 entry table for cubical polygonization
*/
static void makecubetable()
{
static bool is_done = false;
int i, e, c, done[12], pos[8];
if (is_done) {
return;
}
is_done = true;
for (i = 0; i < 256; i++) {
for (e = 0; e < 12; e++) {
done[e] = 0;
}
for (c = 0; c < 8; c++) {
pos[c] = MB_BIT(i, c);
}
for (e = 0; e < 12; e++) {
if (!done[e] && (pos[corner1[e]] != pos[corner2[e]])) {
INTLIST *ints = nullptr;
INTLISTS *lists = static_cast<INTLISTS *>(MEM_callocN(sizeof(INTLISTS), "mball_intlist"));
int start = e, edge = e;
/* get face that is to right of edge from pos to neg corner: */
int face = pos[corner1[e]] ? rightface[e] : leftface[e];
while (true) {
edge = nextcwedge(edge, face);
done[edge] = 1;
if (pos[corner1[edge]] != pos[corner2[edge]]) {
INTLIST *tmp = ints;
ints = static_cast<INTLIST *>(MEM_callocN(sizeof(INTLIST), "mball_intlist"));
ints->i = edge;
ints->next = tmp; /* add edge to head of list */
if (edge == start) {
break;
}
face = otherface(edge, face);
}
}
lists->list = ints; /* add ints to head of table entry */
lists->next = cubetable[i];
cubetable[i] = lists;
}
}
}
for (i = 0; i < 256; i++) {
INTLISTS *polys;
faces[i] = 0;
for (polys = cubetable[i]; polys; polys = polys->next) {
INTLIST *edges;
for (edges = polys->list; edges; edges = edges->next) {
if (ELEM(edges->i, LB, LT, LN, LF)) {
faces[i] |= 1 << L;
}
if (ELEM(edges->i, RB, RT, RN, RF)) {
faces[i] |= 1 << R;
}
if (ELEM(edges->i, LB, RB, BN, BF)) {
faces[i] |= 1 << B;
}
if (ELEM(edges->i, LT, RT, TN, TF)) {
faces[i] |= 1 << T;
}
if (ELEM(edges->i, LN, RN, BN, TN)) {
faces[i] |= 1 << N;
}
if (ELEM(edges->i, LF, RF, BF, TF)) {
faces[i] |= 1 << F;
}
}
}
}
}
void BKE_mball_cubeTable_free()
{
for (int i = 0; i < 256; i++) {
INTLISTS *lists = cubetable[i];
while (lists) {
INTLISTS *nlists = lists->next;
INTLIST *ints = lists->list;
while (ints) {
INTLIST *nints = ints->next;
MEM_freeN(ints);
ints = nints;
}
MEM_freeN(lists);
lists = nlists;
}
cubetable[i] = nullptr;
}
}
/**** Storage ****/
/**
* Inserts cube at lattice i, j, k into hash table, marking it as "done"
*/
static int setcenter(PROCESS *process, CENTERLIST *table[], const int i, const int j, const int k)
{
int index;
CENTERLIST *newc, *l, *q;
index = HASH(i, j, k);
q = table[index];
for (l = q; l != nullptr; l = l->next) {
if (l->i == i && l->j == j && l->k == k) {
return 1;
}
}
newc = static_cast<CENTERLIST *>(BLI_memarena_alloc(process->pgn_elements, sizeof(CENTERLIST)));
newc->i = i;
newc->j = j;
newc->k = k;
newc->next = q;
table[index] = newc;
return 0;
}
/**
* Sets vid of vertex lying on given edge.
*/
static void setedge(PROCESS *process, int i1, int j1, int k1, int i2, int j2, int k2, int vid)
{
int index;
EDGELIST *newe;
if (i1 > i2 || (i1 == i2 && (j1 > j2 || (j1 == j2 && k1 > k2)))) {
int t = i1;
i1 = i2;
i2 = t;
t = j1;
j1 = j2;
j2 = t;
t = k1;
k1 = k2;
k2 = t;
}
index = HASH(i1, j1, k1) + HASH(i2, j2, k2);
newe = static_cast<EDGELIST *>(BLI_memarena_alloc(process->pgn_elements, sizeof(EDGELIST)));
newe->i1 = i1;
newe->j1 = j1;
newe->k1 = k1;
newe->i2 = i2;
newe->j2 = j2;
newe->k2 = k2;
newe->vid = vid;
newe->next = process->edges[index];
process->edges[index] = newe;
}
/**
* \return vertex id for edge; return -1 if not set
*/
static int getedge(EDGELIST *table[], int i1, int j1, int k1, int i2, int j2, int k2)
{
EDGELIST *q;
if (i1 > i2 || (i1 == i2 && (j1 > j2 || (j1 == j2 && k1 > k2)))) {
int t = i1;
i1 = i2;
i2 = t;
t = j1;
j1 = j2;
j2 = t;
t = k1;
k1 = k2;
k2 = t;
}
q = table[HASH(i1, j1, k1) + HASH(i2, j2, k2)];
for (; q != nullptr; q = q->next) {
if (q->i1 == i1 && q->j1 == j1 && q->k1 == k1 && q->i2 == i2 && q->j2 == j2 && q->k2 == k2) {
return q->vid;
}
}
return -1;
}
/**
* Adds a vertex, expands memory if needed.
*/
static void addtovertices(PROCESS *process, const float v[3], const float no[3])
{
process->co.append(v);
process->no.append(no);
}
#ifndef USE_ACCUM_NORMAL
/**
* Computes normal from density field at given point.
*
* \note Doesn't do normalization!
*/
static void vnormal(PROCESS *process, const float point[3], float r_no[3])
{
const float delta = process->delta;
const float f = metaball(process, point[0], point[1], point[2]);
r_no[0] = metaball(process, point[0] + delta, point[1], point[2]) - f;
r_no[1] = metaball(process, point[0], point[1] + delta, point[2]) - f;
r_no[2] = metaball(process, point[0], point[1], point[2] + delta) - f;
}
#endif /* USE_ACCUM_NORMAL */
/**
* \return the id of vertex between two corners.
*
* If it wasn't previously computed, does #converge() and adds vertex to process.
*/
static int vertid(PROCESS *process, const CORNER *c1, const CORNER *c2)
{
float v[3], no[3];
int vid = getedge(process->edges, c1->i, c1->j, c1->k, c2->i, c2->j, c2->k);
if (vid != -1) {
return vid; /* previously computed */
}
converge(process, c1, c2, v); /* position */
#ifdef USE_ACCUM_NORMAL
zero_v3(no);
#else
vnormal(process, v, no);
#endif
addtovertices(process, v, no); /* save vertex */
vid = int(process->co.size()) - 1;
setedge(process, c1->i, c1->j, c1->k, c2->i, c2->j, c2->k, vid);
return vid;
}
/**
* Given two corners, computes approximation of surface intersection point between them.
* In case of small threshold, do bisection.
*/
static void converge(PROCESS *process, const CORNER *c1, const CORNER *c2, float r_p[3])
{
float c1_value, c1_co[3];
float c2_value, c2_co[3];
if (c1->value < c2->value) {
c1_value = c2->value;
copy_v3_v3(c1_co, c2->co);
c2_value = c1->value;
copy_v3_v3(c2_co, c1->co);
}
else {
c1_value = c1->value;
copy_v3_v3(c1_co, c1->co);
c2_value = c2->value;
copy_v3_v3(c2_co, c2->co);
}
for (uint i = 0; i < process->converge_res; i++) {
interp_v3_v3v3(r_p, c1_co, c2_co, 0.5f);
float dens = metaball(process, r_p[0], r_p[1], r_p[2]);
if (dens > 0.0f) {
c1_value = dens;
copy_v3_v3(c1_co, r_p);
}
else {
c2_value = dens;
copy_v3_v3(c2_co, r_p);
}
}
float tmp = -c1_value / (c2_value - c1_value);
interp_v3_v3v3(r_p, c1_co, c2_co, tmp);
}
/**
* Adds cube at given lattice position to cube stack of process.
*/
static void add_cube(PROCESS *process, int i, int j, int k)
{
CUBES *ncube;
int n;
/* test if cube has been found before */
if (setcenter(process, process->centers, i, j, k) == 0) {
/* push cube on stack: */
ncube = static_cast<CUBES *>(BLI_memarena_alloc(process->pgn_elements, sizeof(CUBES)));
ncube->next = process->cubes;
process->cubes = ncube;
ncube->cube.i = i;
ncube->cube.j = j;
ncube->cube.k = k;
/* set corners of initial cube: */
for (n = 0; n < 8; n++) {
ncube->cube.corners[n] = setcorner(
process, i + MB_BIT(n, 2), j + MB_BIT(n, 1), k + MB_BIT(n, 0));
}
}
}
static void next_lattice(int r[3], const float pos[3], const float size)
{
r[0] = int(ceil((pos[0] / size) + 0.5f));
r[1] = int(ceil((pos[1] / size) + 0.5f));
r[2] = int(ceil((pos[2] / size) + 0.5f));
}
static void prev_lattice(int r[3], const float pos[3], const float size)
{
next_lattice(r, pos, size);
r[0]--;
r[1]--;
r[2]--;
}
static void closest_latice(int r[3], const float pos[3], const float size)
{
r[0] = int(floorf(pos[0] / size + 1.0f));
r[1] = int(floorf(pos[1] / size + 1.0f));
r[2] = int(floorf(pos[2] / size + 1.0f));
}
/**
* Find at most 26 cubes to start polygonization from.
*/
static void find_first_points(PROCESS *process, const uint em)
{
const MetaElem *ml;
int center[3], lbn[3], rtf[3], it[3], dir[3], add[3];
float tmp[3], a, b;
ml = process->mainb[em];
mid_v3_v3v3(tmp, ml->bb->vec[0], ml->bb->vec[6]);
closest_latice(center, tmp, process->size);
prev_lattice(lbn, ml->bb->vec[0], process->size);
next_lattice(rtf, ml->bb->vec[6], process->size);
for (dir[0] = -1; dir[0] <= 1; dir[0]++) {
for (dir[1] = -1; dir[1] <= 1; dir[1]++) {
for (dir[2] = -1; dir[2] <= 1; dir[2]++) {
if (dir[0] == 0 && dir[1] == 0 && dir[2] == 0) {
continue;
}
copy_v3_v3_int(it, center);
b = setcorner(process, it[0], it[1], it[2])->value;
do {
it[0] += dir[0];
it[1] += dir[1];
it[2] += dir[2];
a = b;
b = setcorner(process, it[0], it[1], it[2])->value;
if (a * b < 0.0f) {
add[0] = it[0] - dir[0];
add[1] = it[1] - dir[1];
add[2] = it[2] - dir[2];
DO_MIN(it, add);
add_cube(process, add[0], add[1], add[2]);
break;
}
} while ((it[0] > lbn[0]) && (it[1] > lbn[1]) && (it[2] > lbn[2]) && (it[0] < rtf[0]) &&
(it[1] < rtf[1]) && (it[2] < rtf[2]));
}
}
}
}
/**
* The main polygonization processing function.
* Allocates memory, makes cube-table,
* finds starting surface points
* and processes cubes on the stack until none left.
*/
static void polygonize(PROCESS *process)
{
CUBE c;
process->centers = static_cast<CENTERLIST **>(
MEM_callocN(HASHSIZE * sizeof(CENTERLIST *), "mbproc->centers"));
process->corners = static_cast<CORNER **>(
MEM_callocN(HASHSIZE * sizeof(CORNER *), "mbproc->corners"));
process->edges = static_cast<EDGELIST **>(
MEM_callocN(2 * HASHSIZE * sizeof(EDGELIST *), "mbproc->edges"));
process->bvh_queue = static_cast<MetaballBVHNode **>(
MEM_callocN(sizeof(MetaballBVHNode *) * process->bvh_queue_size, "Metaball BVH Queue"));
makecubetable();
for (uint i = 0; i < process->totelem; i++) {
find_first_points(process, i);
}
while (process->cubes != nullptr) {
c = process->cubes->cube;
process->cubes = process->cubes->next;
docube(process, &c);
}
}
/**
* Iterates over ALL objects in the scene and all of its sets, including
* making all duplis (not only meta-elements). Copies meta-elements to #process.mainb array.
* Computes bounding boxes for building BVH.
*/
static void init_meta(Depsgraph *depsgraph, PROCESS *process, Scene *scene, Object *ob)
{
Scene *sce_iter = scene;
Base *base;
Object *bob;
MetaBall *mb;
const MetaElem *ml;
float obinv[4][4], obmat[4][4];
uint i;
int obnr, zero_size = 0;
char obname[MAX_ID_NAME];
SceneBaseIter iter;
const eEvaluationMode deg_eval_mode = DEG_get_mode(depsgraph);
const short parenting_dupli_transflag = (OB_DUPLIFACES | OB_DUPLIVERTS);
copy_m4_m4(obmat,
ob->object_to_world); /* to cope with duplicators from BKE_scene_base_iter_next */
invert_m4_m4(obinv, ob->object_to_world);
BLI_string_split_name_number(ob->id.name + 2, '.', obname, &obnr);
/* make main array */
BKE_scene_base_iter_next(depsgraph, &iter, &sce_iter, 0, nullptr, nullptr);
while (BKE_scene_base_iter_next(depsgraph, &iter, &sce_iter, 1, &base, &bob)) {
if (bob->type == OB_MBALL) {
zero_size = 0;
ml = nullptr;
/* If this metaball is the original that's used for duplication, only have it visible when
* the instancer is visible too. */
if ((base->flag_legacy & OB_FROMDUPLI) == 0 && ob->parent != nullptr &&
(ob->parent->transflag & parenting_dupli_transflag) != 0 &&
(BKE_object_visibility(ob->parent, deg_eval_mode) & OB_VISIBLE_SELF) == 0)
{
continue;
}
if (bob == ob && (base->flag_legacy & OB_FROMDUPLI) == 0) {
mb = static_cast<MetaBall *>(ob->data);
if (mb->editelems) {
ml = static_cast<const MetaElem *>(mb->editelems->first);
}
else {
ml = static_cast<const MetaElem *>(mb->elems.first);
}
}
else {
char name[MAX_ID_NAME];
int nr;
BLI_string_split_name_number(bob->id.name + 2, '.', name, &nr);
if (STREQ(obname, name)) {
mb = static_cast<MetaBall *>(bob->data);
if (mb->editelems) {
ml = static_cast<const MetaElem *>(mb->editelems->first);
}
else {
ml = static_cast<const MetaElem *>(mb->elems.first);
}
}
}
/* when metaball object has zero scale, then MetaElem to this MetaBall
* will not be put to mainb array */
if (has_zero_axis_m4(bob->object_to_world)) {
zero_size = 1;
}
else if (bob->parent) {
Object *pob = bob->parent;
while (pob) {
if (has_zero_axis_m4(pob->object_to_world)) {
zero_size = 1;
break;
}
pob = pob->parent;
}
}
if (zero_size) {
while (ml) {
ml = ml->next;
}
}
else {
while (ml) {
if (!(ml->flag & MB_HIDE)) {
float pos[4][4], rot[4][4];
float expx, expy, expz;
float tempmin[3], tempmax[3];
MetaElem *new_ml;
/* make a copy because of duplicates */
new_ml = static_cast<MetaElem *>(
BLI_memarena_alloc(process->pgn_elements, sizeof(MetaElem)));
*(new_ml) = *ml;
new_ml->bb = static_cast<BoundBox *>(
BLI_memarena_alloc(process->pgn_elements, sizeof(BoundBox)));
new_ml->mat = static_cast<float *>(
BLI_memarena_alloc(process->pgn_elements, sizeof(float[4][4])));
new_ml->imat = static_cast<float *>(
BLI_memarena_alloc(process->pgn_elements, sizeof(float[4][4])));
/* too big stiffness seems only ugly due to linear interpolation
* no need to have possibility for too big stiffness */
if (ml->s > 10.0f) {
new_ml->s = 10.0f;
}
else {
new_ml->s = ml->s;
}
/* if metaball is negative, set stiffness negative */
if (new_ml->flag & MB_NEGATIVE) {
new_ml->s = -new_ml->s;
}
/* Translation of MetaElem */
unit_m4(pos);
pos[3][0] = ml->x;
pos[3][1] = ml->y;
pos[3][2] = ml->z;
/* Rotation of MetaElem is stored in quat */
quat_to_mat4(rot, ml->quat);
/* Matrix multiply is as follows:
* basis object space ->
* world ->
* ml object space ->
* position ->
* rotation ->
* ml local space
*/
mul_m4_series((float(*)[4])new_ml->mat, obinv, bob->object_to_world, pos, rot);
/* ml local space -> basis object space */
invert_m4_m4((float(*)[4])new_ml->imat, (float(*)[4])new_ml->mat);
/* rad2 is inverse of squared radius */
new_ml->rad2 = 1 / (ml->rad * ml->rad);
/* initial dimensions = radius */
expx = ml->rad;
expy = ml->rad;
expz = ml->rad;
switch (ml->type) {
case MB_BALL:
break;
case MB_CUBE: /* cube is "expanded" by expz, expy and expx */
expz += ml->expz;
ATTR_FALLTHROUGH;
case MB_PLANE: /* plane is "expanded" by expy and expx */
expy += ml->expy;
ATTR_FALLTHROUGH;
case MB_TUBE: /* tube is "expanded" by expx */
expx += ml->expx;
break;
case MB_ELIPSOID: /* ellipsoid is "stretched" by exp* */
expx *= ml->expx;
expy *= ml->expy;
expz *= ml->expz;
break;
}
/* untransformed Bounding Box of MetaElem */
/* TODO: its possible the elem type has been changed and the exp*
* values can use a fallback. */
copy_v3_fl3(new_ml->bb->vec[0], -expx, -expy, -expz); /* 0 */
copy_v3_fl3(new_ml->bb->vec[1], +expx, -expy, -expz); /* 1 */
copy_v3_fl3(new_ml->bb->vec[2], +expx, +expy, -expz); /* 2 */
copy_v3_fl3(new_ml->bb->vec[3], -expx, +expy, -expz); /* 3 */
copy_v3_fl3(new_ml->bb->vec[4], -expx, -expy, +expz); /* 4 */
copy_v3_fl3(new_ml->bb->vec[5], +expx, -expy, +expz); /* 5 */
copy_v3_fl3(new_ml->bb->vec[6], +expx, +expy, +expz); /* 6 */
copy_v3_fl3(new_ml->bb->vec[7], -expx, +expy, +expz); /* 7 */
/* Transformation of meta-elem bounding-box. */
for (i = 0; i < 8; i++) {
mul_m4_v3((float(*)[4])new_ml->mat, new_ml->bb->vec[i]);
}
/* Find max and min of transformed bounding-box. */
INIT_MINMAX(tempmin, tempmax);
for (i = 0; i < 8; i++) {
DO_MINMAX(new_ml->bb->vec[i], tempmin, tempmax);
}
/* Set only point 0 and 6 - AABB of meta-elem. */
copy_v3_v3(new_ml->bb->vec[0], tempmin);
copy_v3_v3(new_ml->bb->vec[6], tempmax);
/* add new_ml to mainb[] */
if (UNLIKELY(process->totelem == process->mem)) {
process->mem = process->mem * 2 + 10;
process->mainb = static_cast<MetaElem **>(
MEM_reallocN(process->mainb, sizeof(MetaElem *) * process->mem));
}
process->mainb[process->totelem++] = new_ml;
}
ml = ml->next;
}
}
}
}
/* Compute AABB of all meta-elems. */
if (process->totelem > 0) {
copy_v3_v3(process->allbb.min, process->mainb[0]->bb->vec[0]);
copy_v3_v3(process->allbb.max, process->mainb[0]->bb->vec[6]);
for (i = 1; i < process->totelem; i++) {
make_box_union(process->mainb[i]->bb, &process->allbb, &process->allbb);
}
}
}
Mesh *BKE_mball_polygonize(Depsgraph *depsgraph, Scene *scene, Object *ob)
{
PROCESS process{};
const bool is_render = DEG_get_mode(depsgraph) == DAG_EVAL_RENDER;
MetaBall *mb = static_cast<MetaBall *>(ob->data);
process.thresh = mb->thresh;
if (process.thresh < 0.001f) {
process.converge_res = 16;
}
else if (process.thresh < 0.01f) {
process.converge_res = 8;
}
else if (process.thresh < 0.1f) {
process.converge_res = 4;
}
else {
process.converge_res = 2;
}
if (!is_render && (mb->flag == MB_UPDATE_NEVER)) {
return nullptr;
}
if ((G.moving & (G_TRANSFORM_OBJ | G_TRANSFORM_EDIT)) && mb->flag == MB_UPDATE_FAST) {
return nullptr;
}
if (is_render) {
process.size = mb->rendersize;
}
else {
process.size = mb->wiresize;
if ((G.moving & (G_TRANSFORM_OBJ | G_TRANSFORM_EDIT)) && mb->flag == MB_UPDATE_HALFRES) {
process.size *= 2.0f;
}
}
process.delta = process.size * 0.001f;
process.co.reserve(MBALL_ARRAY_LEN_INIT);
process.no.reserve(MBALL_ARRAY_LEN_INIT);
process.pgn_elements = BLI_memarena_new(BLI_MEMARENA_STD_BUFSIZE, "Metaball memarena");
/* initialize all mainb (MetaElems) */
init_meta(depsgraph, &process, scene, ob);
if (process.totelem == 0) {
freepolygonize(&process);
return nullptr;
}
build_bvh_spatial(&process, &process.metaball_bvh, 0, process.totelem, &process.allbb);
/* Don't polygonize meta-balls with too high resolution (base meta-ball too small).
* NOTE: Epsilon was 0.0001f but this was giving problems for blood animation for
* the open movie "Sintel", using 0.00001f. */
if (ob->scale[0] < 0.00001f * (process.allbb.max[0] - process.allbb.min[0]) ||
ob->scale[1] < 0.00001f * (process.allbb.max[1] - process.allbb.min[1]) ||
ob->scale[2] < 0.00001f * (process.allbb.max[2] - process.allbb.min[2]))
{
freepolygonize(&process);
return nullptr;
}
polygonize(&process);
if (process.curindex == 0) {
freepolygonize(&process);
return nullptr;
}
freepolygonize(&process);
int corners_num = 0;
for (uint i = 0; i < process.curindex; i++) {
const int *indices = process.indices[i];
const int count = indices[2] != indices[3] ? 4 : 3;
corners_num += count;
}
Mesh *mesh = BKE_mesh_new_nomain(int(process.co.size()), 0, int(process.curindex), corners_num);
mesh->vert_positions_for_write().copy_from(process.co);
blender::MutableSpan<int> face_offsets = mesh->face_offsets_for_write();
blender::MutableSpan<int> corner_verts = mesh->corner_verts_for_write();
int loop_offset = 0;
for (int i = 0; i < mesh->faces_num; i++) {
const int *indices = process.indices[i];
const int count = indices[2] != indices[3] ? 4 : 3;
face_offsets[i] = loop_offset;
corner_verts[loop_offset] = indices[0];
corner_verts[loop_offset + 1] = indices[1];
corner_verts[loop_offset + 2] = indices[2];
if (count == 4) {
corner_verts[loop_offset + 3] = indices[3];
}
loop_offset += count;
}
MEM_freeN(process.indices);
for (int i = 0; i < mesh->totvert; i++) {
normalize_v3(process.no[i]);
}
blender::bke::mesh_vert_normals_assign(*mesh, std::move(process.no));
BKE_mesh_calc_edges(mesh, false, false);
return mesh;
}