diff options
author | Daniel Genrich <daniel.genrich@gmx.net> | 2008-08-07 21:27:29 +0400 |
---|---|---|
committer | Daniel Genrich <daniel.genrich@gmx.net> | 2008-08-07 21:27:29 +0400 |
commit | c25bb4685acf53fd98f628c5ed18881d3c1a4cee (patch) | |
tree | 348eab73d3b42e9eae66e8eb9b1354c6839e4b88 /source | |
parent | 15952fb26caccc5207234b768bf542070c0ec404 (diff) |
BVH-KDOP update (merge from shrinkwrap branch): supports raytracing, nearest neighbour, non-recursive now, faster than kdtree.c implementation normaly, divided into 2 sources: generla structure in blenlib, mesh/derivedmesh depending interface stuff in blenkernel
Diffstat (limited to 'source')
-rw-r--r-- | source/blender/blenkernel/BKE_bvhutils.h | 98 | ||||
-rw-r--r-- | source/blender/blenkernel/intern/bvhutils.c | 426 | ||||
-rw-r--r-- | source/blender/blenlib/BLI_kdopbvh.h | 36 | ||||
-rw-r--r-- | source/blender/blenlib/intern/BLI_kdopbvh.c | 722 |
4 files changed, 1194 insertions, 88 deletions
diff --git a/source/blender/blenkernel/BKE_bvhutils.h b/source/blender/blenkernel/BKE_bvhutils.h new file mode 100644 index 00000000000..dd9ea61f24b --- /dev/null +++ b/source/blender/blenkernel/BKE_bvhutils.h @@ -0,0 +1,98 @@ +/** + * + * $Id$ + * + * ***** 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * The Original Code is Copyright (C) 2006 by NaN Holding BV. + * All rights reserved. + * + * The Original Code is: all of this file. + * + * Contributor(s): André Pinto + * + * ***** END GPL LICENSE BLOCK ***** + */ +#ifndef BKE_BVHUTILS_H +#define BKE_BVHUTILS_H + +#include "BLI_kdopbvh.h" + +/* + * This header encapsulates necessary code to buld a BVH + */ + +struct DerivedMesh; +struct MVert; +struct MFace; + +/* + * struct that kepts basic information about a BVHTree build from a mesh + */ +typedef struct BVHTreeFromMesh +{ + struct BVHTree *tree; + + /* default callbacks to bvh nearest and raycast */ + BVHTree_NearestPointCallback nearest_callback; + BVHTree_RayCastCallback raycast_callback; + + /* Mesh represented on this BVHTree */ + struct DerivedMesh *mesh; + + /* Vertex array, so that callbacks have instante access to data */ + struct MVert *vert; + struct MFace *face; + + /* radius for raycast */ + float sphere_radius; + +} BVHTreeFromMesh; + +/* + * Builds a bvh tree where nodes are the vertexs of the given mesh. + * Configures BVHTreeFromMesh. + * + * The tree is build in mesh space coordinates, this means special care must be made on queries + * so that the coordinates and rays are first translated on the mesh local coordinates. + * Reason for this is that later bvh_from_mesh_* might use a cache system and so it becames possible to reuse + * a BVHTree. + * + * free_bvhtree_from_mesh should be called when the tree is no longer needed. + */ +void bvhtree_from_mesh_verts(struct BVHTreeFromMesh *data, struct DerivedMesh *mesh, float epsilon, int tree_type, int axis); + +/* + * Builds a bvh tree where nodes are the faces of the given mesh. + * Configures BVHTreeFromMesh. + * + * The tree is build in mesh space coordinates, this means special care must be made on queries + * so that the coordinates and rays are first translated on the mesh local coordinates. + * Reason for this is that later bvh_from_mesh_* might use a cache system and so it becames possible to reuse + * a BVHTree. + * + * free_bvhtree_from_mesh should be called when the tree is no longer needed. + */ +void bvhtree_from_mesh_faces(struct BVHTreeFromMesh *data, struct DerivedMesh *mesh, float epsilon, int tree_type, int axis); + +/* + * Frees data allocated by a call to bvhtree_from_mesh_*. + */ +void free_bvhtree_from_mesh(struct BVHTreeFromMesh *data); + +#endif + diff --git a/source/blender/blenkernel/intern/bvhutils.c b/source/blender/blenkernel/intern/bvhutils.c new file mode 100644 index 00000000000..5b68a637ea2 --- /dev/null +++ b/source/blender/blenkernel/intern/bvhutils.c @@ -0,0 +1,426 @@ +/** + * + * $Id$ + * + * ***** 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * The Original Code is Copyright (C) Blender Foundation. + * All rights reserved. + * + * The Original Code is: all of this file. + * + * Contributor(s): André Pinto. + * + * ***** END GPL LICENSE BLOCK ***** + */ +#include <stdio.h> +#include <string.h> +#include <math.h> + +#include "BKE_bvhutils.h" + +#include "DNA_object_types.h" +#include "DNA_modifier_types.h" +#include "DNA_meshdata_types.h" + +#include "BKE_DerivedMesh.h" +#include "BKE_utildefines.h" +#include "BKE_deform.h" +#include "BKE_cdderivedmesh.h" +#include "BKE_displist.h" +#include "BKE_global.h" + +#include "BLI_arithb.h" + +/* Math stuff for ray casting on mesh faces and for nearest surface */ + +static float nearest_point_in_tri_surface(const float *point, const float *v0, const float *v1, const float *v2, float *nearest); + +#define ISECT_EPSILON 1e-6 +static float ray_tri_intersection(const BVHTreeRay *ray, const float m_dist, const float *v0, const float *v1, const float *v2) +{ + float dist; + + if(RayIntersectsTriangle(ray->origin, ray->direction, v0, v1, v2, &dist, NULL)) + return dist; + + return FLT_MAX; +} + +static float sphereray_tri_intersection(const BVHTreeRay *ray, float radius, const float m_dist, const float *v0, const float *v1, const float *v2) +{ + + float idist; + float p1[3]; + float plane_normal[3], hit_point[3]; + + CalcNormFloat((float*)v0, (float*)v1, (float*)v2, plane_normal); + + VECADDFAC( p1, ray->origin, ray->direction, m_dist); + if(SweepingSphereIntersectsTriangleUV(ray->origin, p1, radius, v0, v1, v2, &idist, &hit_point)) + { + return idist * m_dist; + } + + return FLT_MAX; +} + +/* + * This calculates the distance from point to the plane + * Distance is negative if point is on the back side of plane + */ +static float point_plane_distance(const float *point, const float *plane_point, const float *plane_normal) +{ + float pp[3]; + VECSUB(pp, point, plane_point); + return INPR(pp, plane_normal); +} +static float choose_nearest(const float v0[2], const float v1[2], const float point[2], float closest[2]) +{ + float d[2][2], sdist[2]; + VECSUB2D(d[0], v0, point); + VECSUB2D(d[1], v1, point); + + sdist[0] = d[0][0]*d[0][0] + d[0][1]*d[0][1]; + sdist[1] = d[1][0]*d[1][0] + d[1][1]*d[1][1]; + + if(sdist[0] < sdist[1]) + { + if(closest) + VECCOPY2D(closest, v0); + return sdist[0]; + } + else + { + if(closest) + VECCOPY2D(closest, v1); + return sdist[1]; + } +} +/* + * calculates the closest point between point-tri (2D) + * returns that tri must be right-handed + * Returns square distance + */ +static float closest_point_in_tri2D(const float point[2], /*const*/ float tri[3][2], float closest[2]) +{ + float edge_di[2]; + float v_point[2]; + float proj[2]; //point projected over edge-dir, edge-normal (witouth normalized edge) + const float *v0 = tri[2], *v1; + float edge_slen, d; //edge squared length + int i; + const float *nearest_vertex = NULL; + + + //for each edge + for(i=0, v0=tri[2], v1=tri[0]; i < 3; v0=tri[i++], v1=tri[i]) + { + VECSUB2D(edge_di, v1, v0); + VECSUB2D(v_point, point, v0); + + proj[1] = v_point[0]*edge_di[1] - v_point[1]*edge_di[0]; //dot product with edge normal + + //point inside this edge + if(proj[1] < 0) + continue; + + proj[0] = v_point[0]*edge_di[0] + v_point[1]*edge_di[1]; + + //closest to this edge is v0 + if(proj[0] < 0) + { + if(nearest_vertex == NULL || nearest_vertex == v0) + nearest_vertex = v0; + else + { + //choose nearest + return choose_nearest(nearest_vertex, v0, point, closest); + } + i++; //We can skip next edge + continue; + } + + edge_slen = edge_di[0]*edge_di[0] + edge_di[1]*edge_di[1]; //squared edge len + //closest to this edge is v1 + if(proj[0] > edge_slen) + { + if(nearest_vertex == NULL || nearest_vertex == v1) + nearest_vertex = v1; + else + { + return choose_nearest(nearest_vertex, v1, point, closest); + } + continue; + } + + //nearest is on this edge + d= proj[1] / edge_slen; + closest[0] = point[0] - edge_di[1] * d; + closest[1] = point[1] + edge_di[0] * d; + + return proj[1]*proj[1]/edge_slen; + } + + if(nearest_vertex) + { + VECSUB2D(v_point, nearest_vertex, point); + VECCOPY2D(closest, nearest_vertex); + return v_point[0]*v_point[0] + v_point[1]*v_point[1]; + } + else + { + VECCOPY(closest, point); //point is already inside + return 0.0f; + } +} + +/* + * Returns the square of the minimum distance between the point and a triangle surface + * If nearest is not NULL the nearest surface point is written on it + */ +static float nearest_point_in_tri_surface(const float *point, const float *v0, const float *v1, const float *v2, float *nearest) +{ + //Lets solve the 2D problem (closest point-tri) + float normal_dist, plane_sdist, plane_offset; + float du[3], dv[3], dw[3]; //orthogonal axis (du=(v0->v1), dw=plane normal) + + float p_2d[2], tri_2d[3][2], nearest_2d[2]; + + CalcNormFloat((float*)v0, (float*)v1, (float*)v2, dw); + + //point-plane distance and calculate axis + normal_dist = point_plane_distance(point, v0, dw); + + // OPTIMIZATION + // if we are only interested in nearest distance if its closer than some distance already found + // we can: + // if(normal_dist*normal_dist >= best_dist_so_far) return FLOAT_MAX; + // + + VECSUB(du, v1, v0); + Normalize(du); + Crossf(dv, dw, du); + plane_offset = INPR(v0, dw); + + //project stuff to 2d + tri_2d[0][0] = INPR(du, v0); + tri_2d[0][1] = INPR(dv, v0); + + tri_2d[1][0] = INPR(du, v1); + tri_2d[1][1] = INPR(dv, v1); + + tri_2d[2][0] = INPR(du, v2); + tri_2d[2][1] = INPR(dv, v2); + + p_2d[0] = INPR(du, point); + p_2d[1] = INPR(dv, point); + + //we always have a right-handed tri + //this should always happen because of the way normal is calculated + plane_sdist = closest_point_in_tri2D(p_2d, tri_2d, nearest_2d); + + //project back to 3d + if(nearest) + { + nearest[0] = du[0]*nearest_2d[0] + dv[0] * nearest_2d[1] + dw[0] * plane_offset; + nearest[1] = du[1]*nearest_2d[0] + dv[1] * nearest_2d[1] + dw[1] * plane_offset; + nearest[2] = du[2]*nearest_2d[0] + dv[2] * nearest_2d[1] + dw[2] * plane_offset; + } + + return plane_sdist + normal_dist*normal_dist; +} + + +/* + * BVH from meshs callbacks + */ + +// Callback to bvh tree nearest point. The tree must bust have been built using bvhtree_from_mesh_faces. +// userdata must be a BVHMeshCallbackUserdata built from the same mesh as the tree. +static void mesh_faces_nearest_point(void *userdata, int index, const float *co, BVHTreeNearest *nearest) +{ + const BVHTreeFromMesh *data = (BVHTreeFromMesh*) userdata; + MVert *vert = data->vert; + MFace *face = data->face + index; + + float *t0, *t1, *t2, *t3; + t0 = vert[ face->v1 ].co; + t1 = vert[ face->v2 ].co; + t2 = vert[ face->v3 ].co; + t3 = face->v4 ? vert[ face->v4].co : NULL; + + + do + { + float nearest_tmp[3], dist; + + dist = nearest_point_in_tri_surface(co,t0, t1, t2, nearest_tmp); + if(dist < nearest->dist) + { + nearest->index = index; + nearest->dist = dist; + VECCOPY(nearest->co, nearest_tmp); + CalcNormFloat((float*)t0, (float*)t1, (float*)t2, nearest->no); //TODO.. (interpolate normals from the vertexs coordinates? + } + + + t1 = t2; + t2 = t3; + t3 = NULL; + + } while(t2); +} + +// Callback to bvh tree raycast. The tree must bust have been built using bvhtree_from_mesh_faces. +// userdata must be a BVHMeshCallbackUserdata built from the same mesh as the tree. +static void mesh_faces_spherecast(void *userdata, int index, const BVHTreeRay *ray, BVHTreeRayHit *hit) +{ + const BVHTreeFromMesh *data = (BVHTreeFromMesh*) userdata; + MVert *vert = data->vert; + MFace *face = data->face + index; + + float *t0, *t1, *t2, *t3; + t0 = vert[ face->v1 ].co; + t1 = vert[ face->v2 ].co; + t2 = vert[ face->v3 ].co; + t3 = face->v4 ? vert[ face->v4].co : NULL; + + + do + { + float dist; + if(data->sphere_radius == 0.0f) + dist = ray_tri_intersection(ray, hit->dist, t0, t1, t2); + else + dist = sphereray_tri_intersection(ray, data->sphere_radius, hit->dist, t0, t1, t2); + + if(dist >= 0 && dist < hit->dist) + { + hit->index = index; + hit->dist = dist; + VECADDFAC(hit->co, ray->origin, ray->direction, dist); + + CalcNormFloat(t0, t1, t2, hit->no); + } + + t1 = t2; + t2 = t3; + t3 = NULL; + + } while(t2); +} + +/* + * BVH builders + */ +// Builds a bvh tree.. where nodes are the vertexs of the given mesh +void bvhtree_from_mesh_verts(BVHTreeFromMesh *data, DerivedMesh *mesh, float epsilon, int tree_type, int axis) +{ + int i; + int numVerts= mesh->getNumVerts(mesh); + MVert *vert = mesh->getVertDataArray(mesh, CD_MVERT); + BVHTree *tree = NULL; + + memset(data, 0, sizeof(*data)); + + if(vert == NULL) + { + printf("bvhtree cant be build: cant get a vertex array"); + return; + } + + tree = BLI_bvhtree_new(numVerts, epsilon, tree_type, axis); + if(tree != NULL) + { + for(i = 0; i < numVerts; i++) + BLI_bvhtree_insert(tree, i, vert[i].co, 1); + + BLI_bvhtree_balance(tree); + + data->tree = tree; + + //a NULL nearest callback works fine + //remeber the min distance to point is the same as the min distance to BV of point + data->nearest_callback = NULL; + data->raycast_callback = NULL; + + data->mesh = mesh; + data->vert = mesh->getVertDataArray(mesh, CD_MVERT); + data->face = mesh->getFaceDataArray(mesh, CD_MFACE); + + data->sphere_radius = epsilon; + } +} + +// Builds a bvh tree.. where nodes are the faces of the given mesh. +void bvhtree_from_mesh_faces(BVHTreeFromMesh *data, DerivedMesh *mesh, float epsilon, int tree_type, int axis) +{ + int i; + int numFaces= mesh->getNumFaces(mesh); + MVert *vert = mesh->getVertDataArray(mesh, CD_MVERT); + MFace *face = mesh->getFaceDataArray(mesh, CD_MFACE); + BVHTree *tree = NULL; + + memset(data, 0, sizeof(*data)); + + if(vert == NULL && face == NULL) + { + printf("bvhtree cant be build: cant get a vertex/face array"); + return; + } + + /* Create a bvh-tree of the given target */ + tree = BLI_bvhtree_new(numFaces, epsilon, tree_type, axis); + if(tree != NULL) + { + for(i = 0; i < numFaces; i++) + { + float co[4][3]; + VECCOPY(co[0], vert[ face[i].v1 ].co); + VECCOPY(co[1], vert[ face[i].v2 ].co); + VECCOPY(co[2], vert[ face[i].v3 ].co); + if(face[i].v4) + VECCOPY(co[3], vert[ face[i].v4 ].co); + + BLI_bvhtree_insert(tree, i, co[0], face[i].v4 ? 4 : 3); + } + BLI_bvhtree_balance(tree); + + data->tree = tree; + data->nearest_callback = mesh_faces_nearest_point; + data->raycast_callback = mesh_faces_spherecast; + + data->mesh = mesh; + data->vert = mesh->getVertDataArray(mesh, CD_MVERT); + data->face = mesh->getFaceDataArray(mesh, CD_MFACE); + + data->sphere_radius = epsilon; + } +} + +// Frees data allocated by a call to bvhtree_from_mesh_*. +void free_bvhtree_from_mesh(struct BVHTreeFromMesh *data) +{ + if(data->tree) + { + BLI_bvhtree_free(data->tree); + memset( data, 0, sizeof(data) ); + } +} + + diff --git a/source/blender/blenlib/BLI_kdopbvh.h b/source/blender/blenlib/BLI_kdopbvh.h index b81ff0ee66f..6d9a17efebf 100644 --- a/source/blender/blenlib/BLI_kdopbvh.h +++ b/source/blender/blenlib/BLI_kdopbvh.h @@ -1,5 +1,7 @@ /** * + * $Id$ + * * ***** BEGIN GPL LICENSE BLOCK ***** * * This program is free software; you can redistribute it and/or @@ -40,6 +42,35 @@ typedef struct BVHTreeOverlap { int indexB; } BVHTreeOverlap; +typedef struct BVHTreeNearest +{ + int index; /* the index of the nearest found (untouched if none is found within a dist radius from the given coordinates) */ + float co[3]; /* nearest coordinates (untouched it none is found within a dist radius from the given coordinates) */ + float no[3]; /* normal at nearest coordinates (untouched it none is found within a dist radius from the given coordinates) */ + float dist; /* squared distance to search arround */ +} BVHTreeNearest; + +typedef struct BVHTreeRay +{ + float origin[3]; /* ray origin */ + float direction[3]; /* ray direction */ +} BVHTreeRay; + +typedef struct BVHTreeRayHit +{ + int index; /* index of the tree node (untouched if no hit is found) */ + float co[3]; /* coordinates of the hit point */ + float no[3]; /* normal on hit point */ + float dist; /* distance to the hit point */ +} BVHTreeRayHit; + +/* callback must update nearest in case it finds a nearest result */ +typedef void (*BVHTree_NearestPointCallback) (void *userdata, int index, const float *co, BVHTreeNearest *nearest); + +/* callback must update hit in case it finds a nearest successful hit */ +typedef void (*BVHTree_RayCastCallback) (void *userdata, int index, const BVHTreeRay *ray, BVHTreeRayHit *hit); + + BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis); void BLI_bvhtree_free(BVHTree *tree); @@ -56,5 +87,10 @@ BVHTreeOverlap *BLI_bvhtree_overlap(BVHTree *tree1, BVHTree *tree2, int *result) float BLI_bvhtree_getepsilon(BVHTree *tree); +/* find nearest node to the given coordinates (if nearest is given it will only search nodes where square distance is smaller than nearest->dist) */ +int BLI_bvhtree_find_nearest(BVHTree *tree, const float *co, BVHTreeNearest *nearest, BVHTree_NearestPointCallback callback, void *userdata); + +int BLI_bvhtree_ray_cast(BVHTree *tree, const float *co, const float *dir, BVHTreeRayHit *hit, BVHTree_RayCastCallback callback, void *userdata); + #endif // BLI_KDOPBVH_H diff --git a/source/blender/blenlib/intern/BLI_kdopbvh.c b/source/blender/blenlib/intern/BLI_kdopbvh.c index 4ceb9762a7b..ddea701dac5 100644 --- a/source/blender/blenlib/intern/BLI_kdopbvh.c +++ b/source/blender/blenlib/intern/BLI_kdopbvh.c @@ -1,5 +1,7 @@ /** * + * $Id$ + * * ***** BEGIN GPL LICENSE BLOCK ***** * * This program is free software; you can redistribute it and/or @@ -28,8 +30,9 @@ #include "math.h" #include <stdio.h> -#include <stdlib.h> +#include <stdlib.h> #include <string.h> +#include <assert.h> #include "MEM_guardedalloc.h" @@ -44,11 +47,11 @@ typedef struct BVHNode { - struct BVHNode **children; // max 8 children + struct BVHNode **children; // max 8 children struct BVHNode *parent; // needed for bottom - top update - float *bv; // Bounding volume of all nodes, max 13 axis - int index; /* face, edge, vertex index */ - char totnode; // how many nodes are used, used for speedup + float *bv; // Bounding volume of all nodes, max 13 axis + int index; // face, edge, vertex index + char totnode; // how many nodes are used, used for speedup char traversed; // how many nodes already traversed until this level? char main_axis; } BVHNode; @@ -73,7 +76,32 @@ typedef struct BVHOverlapData BVHTreeOverlap *overlap; int i, max_overlap; /* i is number of overlaps */ } BVHOverlapData; -//////////////////////////////////////// + +typedef struct BVHNearestData +{ + BVHTree *tree; + float *co; + BVHTree_NearestPointCallback callback; + void *userdata; + float proj[13]; //coordinates projection over axis + BVHTreeNearest nearest; + +} BVHNearestData; + +typedef struct BVHRayCastData +{ + BVHTree *tree; + + BVHTree_RayCastCallback callback; + void *userdata; + + + BVHTreeRay ray; + float ray_dot_axis[13]; + + BVHTreeRayHit hit; +} BVHRayCastData; +////////////////////////////////////////m //////////////////////////////////////////////////////////////////////// @@ -244,7 +272,7 @@ int partition_nth_element(BVHNode **a, int _begin, int _end, int n, int axis){ int begin = _begin, end = _end, cut; while(end-begin > 3) { - cut = bvh_partition(a, begin, end, bvh_medianof3(a, begin, (begin+end)/2, end-1, axis), axis ); + cut = bvh_partition(a, begin, end, bvh_medianof3(a, begin, (begin+end)/2, end-1, axis), axis ); if(cut <= n) begin = cut; else @@ -255,7 +283,6 @@ int partition_nth_element(BVHNode **a, int _begin, int _end, int n, int axis){ return n; } - ////////////////////////////////////////////////////////////////////////////////////////////////////// void BLI_bvhtree_free(BVHTree *tree) @@ -270,13 +297,35 @@ void BLI_bvhtree_free(BVHTree *tree) } } +// calculate max number of branches +int needed_branches(int tree_type, int leafs) +{ +#if 1 + //Worst case scenary ( return max(0, leafs-tree_type)+1 ) + if(leafs <= tree_type) + return 1; + else + return leafs-tree_type+1; + +#else + //If our bvh kdop is "almost perfect" + //TODO i dont trust the float arithmetic in here (and I am not sure this formula is according to our splitting method) + int i, numbranches = 0; + for(i = 1; i <= (int)ceil((float)((float)log(leafs)/(float)log(tree_type))); i++) + numbranches += (pow(tree_type, i) / tree_type); + + return numbranches; +#endif +} + + BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis) { BVHTree *tree; - int numbranches=0, i; + int numnodes, i; - // only support up to octree - if(tree_type > 8) + // theres not support for trees below binary-trees :P + if(tree_type < 2) return NULL; tree = (BVHTree *)MEM_callocN(sizeof(BVHTree), "BVHTree"); @@ -319,11 +368,10 @@ BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis) } - // calculate max number of branches, our bvh kdop is "almost perfect" - for(i = 1; i <= (int)ceil((float)((float)log(maxsize)/(float)log(tree_type))); i++) - numbranches += (pow(tree_type, i) / tree_type); - - tree->nodes = (BVHNode **)MEM_callocN(sizeof(BVHNode *)*(numbranches+maxsize + tree_type), "BVHNodes"); + //Allocate arrays + numnodes = maxsize + needed_branches(tree_type, maxsize) + tree_type; + + tree->nodes = (BVHNode **)MEM_callocN(sizeof(BVHNode *)*numnodes, "BVHNodes"); if(!tree->nodes) { @@ -331,14 +379,14 @@ BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis) return NULL; } - tree->nodebv = (float*)MEM_callocN(sizeof(float)* axis * (numbranches+maxsize + tree_type), "BVHNodeBV"); + tree->nodebv = (float*)MEM_callocN(sizeof(float)* axis * numnodes, "BVHNodeBV"); if(!tree->nodebv) { MEM_freeN(tree->nodes); MEM_freeN(tree); } - tree->nodechild = (BVHNode**)MEM_callocN(sizeof(BVHNode*) * tree_type * (numbranches+maxsize + tree_type), "BVHNodeBV"); + tree->nodechild = (BVHNode**)MEM_callocN(sizeof(BVHNode*) * tree_type * numnodes, "BVHNodeBV"); if(!tree->nodechild) { MEM_freeN(tree->nodebv); @@ -346,7 +394,7 @@ BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis) MEM_freeN(tree); } - tree->nodearray = (BVHNode *)MEM_callocN(sizeof(BVHNode)*(numbranches+maxsize + tree_type), "BVHNodeArray"); + tree->nodearray = (BVHNode *)MEM_callocN(sizeof(BVHNode)* numnodes, "BVHNodeArray"); if(!tree->nodearray) { @@ -358,7 +406,7 @@ BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis) } //link the dynamic bv and child links - for(i=0; i< numbranches+maxsize + tree_type; i++) + for(i=0; i< numnodes; i++) { tree->nodearray[i].bv = tree->nodebv + i * axis; tree->nodearray[i].children = tree->nodechild + i * tree_type; @@ -373,6 +421,7 @@ BVHTree *BLI_bvhtree_new(int maxsize, float epsilon, char tree_type, char axis) static void create_kdop_hull(BVHTree *tree, BVHNode *node, float *co, int numpoints, int moving) { float newminmax; + float *bv = node->bv; int i, k; // don't init boudings for the moving case @@ -380,8 +429,8 @@ static void create_kdop_hull(BVHTree *tree, BVHNode *node, float *co, int numpoi { for (i = tree->start_axis; i < tree->stop_axis; i++) { - node->bv[2*i] = FLT_MAX; - node->bv[2*i + 1] = -FLT_MAX; + bv[2*i] = FLT_MAX; + bv[2*i + 1] = -FLT_MAX; } } @@ -391,10 +440,10 @@ static void create_kdop_hull(BVHTree *tree, BVHNode *node, float *co, int numpoi for (i = tree->start_axis; i < tree->stop_axis; i++) { newminmax = INPR(&co[k * 3], KDOP_AXES[i]); - if (newminmax < node->bv[2 * i]) - node->bv[2 * i] = newminmax; - if (newminmax > node->bv[(2 * i) + 1]) - node->bv[(2 * i) + 1] = newminmax; + if (newminmax < bv[2 * i]) + bv[2 * i] = newminmax; + if (newminmax > bv[(2 * i) + 1]) + bv[(2 * i) + 1] = newminmax; } } } @@ -405,6 +454,7 @@ static void refit_kdop_hull(BVHTree *tree, BVHNode *node, int start, int end) float newmin,newmax; int i, j; float *bv = node->bv; + for (i = tree->start_axis; i < tree->stop_axis; i++) { @@ -426,18 +476,19 @@ static void refit_kdop_hull(BVHTree *tree, BVHNode *node, int start, int end) bv[(2 * i) + 1] = newmax; } } + } int BLI_bvhtree_insert(BVHTree *tree, int index, float *co, int numpoints) { - BVHNode *node= NULL; int i; + BVHNode *node = NULL; // insert should only possible as long as tree->totbranch is 0 if(tree->totbranch > 0) return 0; - if(tree->totleaf+1 >= MEM_allocN_len(tree->nodes)) + if(tree->totleaf+1 >= MEM_allocN_len(tree->nodes)/sizeof(*(tree->nodes))) return 0; // TODO check if have enough nodes in array @@ -446,6 +497,7 @@ int BLI_bvhtree_insert(BVHTree *tree, int index, float *co, int numpoints) tree->totleaf++; create_kdop_hull(tree, node, co, numpoints, 0); + node->index= index; // inflate the bv with some epsilon for (i = tree->start_axis; i < tree->stop_axis; i++) @@ -454,8 +506,6 @@ int BLI_bvhtree_insert(BVHTree *tree, int index, float *co, int numpoints) node->bv[(2 * i) + 1] += tree->epsilon; // maximum } - node->index= index; - return 1; } @@ -484,21 +534,24 @@ static char get_largest_axis(float *bv) } } -static void bvh_div_nodes(BVHTree *tree, BVHNode *node, int start, int end) +static void bvh_div_nodes(BVHTree *tree, BVHNode *node, int start, int end, int free_node_index) { - int i, tend; - BVHNode *tnode; - int slice = (end-start+tree->tree_type-1)/tree->tree_type; //division rounded up + int i; + + const char laxis = get_largest_axis(node->bv); //determine longest axis to split along + const int slice = (end-start)/tree->tree_type; //division rounded down + const int rest = (end-start)%tree->tree_type; //remainder of division - // Determine which axis to split along - char laxis = get_largest_axis(node->bv); + assert( node->totnode == 0 ); + + node->main_axis = laxis/2; // split nodes along longest axis - for (i=0; start < end; start += slice, i++) //i counts the current child + for (i=0; start < end; node->totnode = ++i) //i counts the current child { - tend = start + slice; + int tend = start + slice + (i < rest ? 1 : 0); - if(tend > end) tend = end; + assert( tend <= end); if(tend-start == 1) // ok, we have 1 left for this node { @@ -507,87 +560,332 @@ static void bvh_div_nodes(BVHTree *tree, BVHNode *node, int start, int end) } else { - tnode = node->children[i] = tree->nodes[tree->totleaf + tree->totbranch] = &(tree->nodearray[tree->totbranch + tree->totleaf]); - tree->totbranch++; + BVHNode *tnode = node->children[i] = tree->nodes[free_node_index] = &(tree->nodearray[free_node_index]); tnode->parent = node; if(tend != end) partition_nth_element(tree->nodes, start, end, tend, laxis); + refit_kdop_hull(tree, tnode, start, tend); - bvh_div_nodes(tree, tnode, start, tend); + + bvh_div_nodes(tree, tnode, start, tend, free_node_index+1); + free_node_index += needed_branches(tree->tree_type, tend-start); } - node->totnode++; + start = tend; } return; } +static void omp_bvh_div_nodes(BVHTree *tree, BVHNode *node, int start, int end, int free_node_index) +{ + int i; + + const char laxis = get_largest_axis(node->bv); //determine longest axis to split along + const int slice = (end-start)/tree->tree_type; //division rounded down + const int rest = (end-start)%tree->tree_type; //remainder of division + + int omp_data_start[tree->tree_type]; + int omp_data_end [tree->tree_type]; + int omp_data_index[tree->tree_type]; + + assert( node->totnode == 0 ); + + node->main_axis = laxis/2; + + // split nodes along longest axis + for (i=0; start < end; node->totnode = ++i) //i counts the current child + { + //Split the rest from left to right (TODO: this doenst makes an optimal tree) + int tend = start + slice + (i < rest ? 1 : 0); + + assert( tend <= end); + + //save data for later OMP + omp_data_start[i] = start; + omp_data_end [i] = tend; + omp_data_index[i] = free_node_index; + + if(tend-start == 1) + { + node->children[i] = tree->nodes[start]; + node->children[i]->parent = node; + } + else + { + node->children[i] = tree->nodes[free_node_index] = &(tree->nodearray[free_node_index]); + node->children[i]->parent = node; + + if(tend != end) + partition_nth_element(tree->nodes, start, end, tend, laxis); + + free_node_index += needed_branches(tree->tree_type, tend-start); + } + + start = tend; + } + +#pragma omp parallel for private(i) schedule(static) + for( i = 0; i < node->totnode; i++) + { + if(omp_data_end[i]-omp_data_start[i] > 1) + { + BVHNode *tnode = node->children[i]; + refit_kdop_hull(tree, tnode, omp_data_start[i], omp_data_end[i]); + bvh_div_nodes (tree, tnode, omp_data_start[i], omp_data_end[i], omp_data_index[i]+1); + } + } + + return; +} + + +static void print_tree(BVHTree *tree, BVHNode *node, int depth) +{ + int i; + for(i=0; i<depth; i++) printf(" "); + printf(" - %d (%d): ", node->index, node - tree->nodearray); + for(i=2*tree->start_axis; i<2*tree->stop_axis; i++) + printf("%.3f ", node->bv[i]); + printf("\n"); + + for(i=0; i<tree->tree_type; i++) + if(node->children[i]) + print_tree(tree, node->children[i], depth+1); +} + #if 0 + static void verify_tree(BVHTree *tree) { int i, j, check = 0; // check the pointer list for(i = 0; i < tree->totleaf; i++) - { +{ if(tree->nodes[i]->parent == NULL) printf("Leaf has no parent: %d\n", i); - else - { - for(j = 0; j < tree->tree_type; j++) - { - if(tree->nodes[i]->parent->children[j] == tree->nodes[i]) - check = 1; - } - if(!check) - { - printf("Parent child relationship doesn't match: %d\n", i); - } - check = 0; - } - } + else +{ + for(j = 0; j < tree->tree_type; j++) +{ + if(tree->nodes[i]->parent->children[j] == tree->nodes[i]) + check = 1; +} + if(!check) +{ + printf("Parent child relationship doesn't match: %d\n", i); +} + check = 0; +} +} // check the leaf list - for(i = 0; i < tree->totleaf; i++) + for(i = 0; i < tree->totleaf; i++) +{ + if(tree->nodearray[i].parent == NULL) + printf("Leaf has no parent: %d\n", i); + else +{ + for(j = 0; j < tree->tree_type; j++) +{ + if(tree->nodearray[i].parent->children[j] == &tree->nodearray[i]) + check = 1; +} + if(!check) +{ + printf("Parent child relationship doesn't match: %d\n", i); +} + check = 0; +} +} + + printf("branches: %d, leafs: %d, total: %d\n", tree->totbranch, tree->totleaf, tree->totbranch + tree->totleaf); +} +#endif + +//Helper data and structures to build generalized implicit trees +//This code can be easily reduced +typedef struct BVHBuildHelper +{ + int tree_type; // + int totleafs; // + + int leafs_per_child [32]; //Min number of leafs that are archievable from a node at depth N + int branches_on_level[32]; //Number of nodes at depth N (tree_type^N) + + int remain_leafs; //Number of leafs that are placed on the level that is not 100% filled + +} BVHBuildHelper; + +static void build_implicit_tree_helper(BVHTree *tree, BVHBuildHelper *data) +{ + int depth = 0; + int remain; + int nnodes; + + data->totleafs = tree->totleaf; + data->tree_type= tree->tree_type; + + //Calculate the smallest tree_type^n such that tree_type^n >= num_leafs + for( + data->leafs_per_child[0] = 1; + data->leafs_per_child[0] < data->totleafs; + data->leafs_per_child[0] *= data->tree_type + ); + + data->branches_on_level[0] = 1; + + //We could stop the loop first (but I am lazy to find out when) + for(depth = 1; depth < 32; depth++) { - if(tree->nodearray[i].parent == NULL) - printf("Leaf has no parent: %d\n", i); - else + data->branches_on_level[depth] = data->branches_on_level[depth-1] * data->tree_type; + data->leafs_per_child [depth] = data->leafs_per_child [depth-1] / data->tree_type; + } + + remain = data->totleafs - data->leafs_per_child[1]; + nnodes = (remain + data->tree_type - 2) / (data->tree_type - 1); + data->remain_leafs = remain + nnodes; +} + +// return the min index of all the leafs archivable with the given branch +static int implicit_leafs_index(BVHBuildHelper *data, int depth, int child_index) +{ + int min_leaf_index = child_index * data->leafs_per_child[depth-1]; + if(min_leaf_index <= data->remain_leafs) + return min_leaf_index; + else if(data->leafs_per_child[depth]) + return data->totleafs - (data->branches_on_level[depth-1] - child_index) * data->leafs_per_child[depth]; + else + return data->remain_leafs; +} + +//WARNING: Beautiful/tricky code starts here :P +//Generalized implicit trees +static void non_recursive_bvh_div_nodes(BVHTree *tree) +{ + int i; + + const int tree_type = tree->tree_type; + const int tree_offset = 2 - tree->tree_type; //this value is 0 (on binary trees) and negative on the others + const int num_leafs = tree->totleaf; + const int num_branches= MAX2(1, (num_leafs + tree_type - 3) / (tree_type-1) ); + + BVHNode* branches_array = tree->nodearray + tree->totleaf - 1; // This code uses 1 index arrays + BVHNode** leafs_array = tree->nodes; + + BVHBuildHelper data; + int depth = 0; + + build_implicit_tree_helper(tree, &data); + + //YAY this could be 1 loop.. but had to split in 2 to remove OMP dependencies + for(i=1; i <= num_branches; i = i*tree_type + tree_offset) + { + const int first_of_next_level = i*tree_type + tree_offset; + const int end_j = MIN2(first_of_next_level, num_branches + 1); //index of last branch on this level + int j; + + depth++; + +#pragma omp parallel for private(j) schedule(static) + for(j = i; j < end_j; j++) { - for(j = 0; j < tree->tree_type; j++) - { - if(tree->nodearray[i].parent->children[j] == &tree->nodearray[i]) - check = 1; - } - if(!check) + int k; + const int parent_level_index= j-i; + BVHNode* parent = branches_array + j; + char split_axis; + + int parent_leafs_begin = implicit_leafs_index(&data, depth, parent_level_index); + int parent_leafs_end = implicit_leafs_index(&data, depth, parent_level_index+1); + + //split_axis = (depth*2 % 6); //use this instead of the 2 following lines for XYZ splitting + + refit_kdop_hull(tree, parent, parent_leafs_begin, parent_leafs_end); + split_axis = get_largest_axis(parent->bv); + + parent->main_axis = split_axis / 2; + + for(k = 0; k < tree_type; k++) { - printf("Parent child relationship doesn't match: %d\n", i); + int child_index = j * tree_type + tree_offset + k; + int child_level_index = child_index - first_of_next_level; //child level index + + int child_leafs_begin = implicit_leafs_index(&data, depth+1, child_level_index); + int child_leafs_end = implicit_leafs_index(&data, depth+1, child_level_index+1); + + assert( k != 0 || child_leafs_begin == parent_leafs_begin); + + if(child_leafs_end - child_leafs_begin > 1) + { + parent->children[k] = branches_array + child_index; + parent->children[k]->parent = parent; + +/* + printf("Add child %d (%d) to branch %d\n", + branches_array + child_index - tree->nodearray, + branches_array[ child_index ].index, + parent - tree->nodearray + ); +*/ + + partition_nth_element(leafs_array, child_leafs_begin, parent_leafs_end, child_leafs_end, split_axis); + } + else if(child_leafs_end - child_leafs_begin == 1) + { +/* + printf("Add child %d (%d) to branch %d\n", + leafs_array[ child_leafs_begin ] - tree->nodearray, + leafs_array[ child_leafs_begin ]->index, + parent - tree->nodearray + ); +*/ + parent->children[k] = leafs_array[ child_leafs_begin ]; + parent->children[k]->parent = parent; + } + else + { + parent->children[k] = NULL; + break; + } + parent->totnode = k+1; } - check = 0; } } - - printf("branches: %d, leafs: %d, total: %d\n", tree->totbranch, tree->totleaf, tree->totbranch + tree->totleaf); + + + for(i = 0; i<num_branches; i++) + tree->nodes[tree->totleaf + i] = branches_array + 1 + i; + + tree->totbranch = num_branches; + +// BLI_bvhtree_update_tree(tree); //Uncoment this for XYZ splitting } -#endif - + void BLI_bvhtree_balance(BVHTree *tree) { - BVHNode *node; - - if(tree->totleaf == 0) - return; - - // create root node - node = tree->nodes[tree->totleaf] = &(tree->nodearray[tree->totleaf]); + if(tree->totleaf == 0) return; + + assert(tree->totbranch == 0); + non_recursive_bvh_div_nodes(tree); + +/* + if(tree->totleaf != 0) + { + // create root node + BVHNode *node = tree->nodes[tree->totleaf] = &(tree->nodearray[tree->totleaf]); tree->totbranch++; - - // refit root bvh node - refit_kdop_hull(tree, tree->nodes[tree->totleaf], 0, tree->totleaf); - // create + balance tree - bvh_div_nodes(tree, tree->nodes[tree->totleaf], 0, tree->totleaf); - - // verify_tree(tree); + < + // refit root bvh node + refit_kdop_hull(tree, node, 0, tree->totleaf); + + // create + balance tree + omp_bvh_div_nodes(tree, node, 0, tree->totleaf, tree->totleaf+1); + tree->totbranch = needed_branches( tree->tree_type, tree->totleaf ); + // verify_tree(tree); +} +*/ + } // overlap - is it possbile for 2 bv's to collide ? @@ -724,6 +1022,7 @@ BVHTreeOverlap *BLI_bvhtree_overlap(BVHTree *tree1, BVHTree *tree2, int *result) } + // bottom up update of bvh tree: // join the 4 children here static void node_join(BVHTree *tree, BVHNode *node) @@ -809,3 +1108,250 @@ float BLI_bvhtree_getepsilon(BVHTree *tree) { return tree->epsilon; } + + + + +/* + * Nearest neighbour + */ +static float squared_dist(const float *a, const float *b) +{ + float tmp[3]; + VECSUB(tmp, a, b); + return INPR(tmp, tmp); +} + +static float calc_nearest_point(BVHNearestData *data, BVHNode *node, float *nearest) +{ + int i; + const float *bv = node->bv; + + //nearest on AABB hull + for(i=0; i != 3; i++, bv += 2) + { + if(bv[0] > data->proj[i]) + nearest[i] = bv[0]; + else if(bv[1] < data->proj[i]) + nearest[i] = bv[1]; + else + nearest[i] = data->proj[i]; + } + +/* + //nearest on a general hull + VECCOPY(nearest, data->co); + for(i = data->tree->start_axis; i != data->tree->stop_axis; i++, bv+=2) + { + float proj = INPR( nearest, KDOP_AXES[i]); + float dl = bv[0] - proj; + float du = bv[1] - proj; + + if(dl > 0) + { + VECADDFAC(nearest, nearest, KDOP_AXES[i], dl); +} + else if(du < 0) + { + VECADDFAC(nearest, nearest, KDOP_AXES[i], du); +} +} +*/ + return squared_dist(data->co, nearest); +} + + +// TODO: use a priority queue to reduce the number of nodes looked on +static void dfs_find_nearest(BVHNearestData *data, BVHNode *node) +{ + int i; + float nearest[3], sdist; + + sdist = calc_nearest_point(data, node, nearest); + if(sdist >= data->nearest.dist) return; + + if(node->totnode == 0) + { + if(data->callback) + data->callback(data->userdata , node->index, data->co, &data->nearest); + else + { + data->nearest.index = node->index; + VECCOPY(data->nearest.co, nearest); + data->nearest.dist = sdist; + } + } + else + { + for(i=0; i != node->totnode; i++) + dfs_find_nearest(data, node->children[i]); + } +} + +int BLI_bvhtree_find_nearest(BVHTree *tree, const float *co, BVHTreeNearest *nearest, BVHTree_NearestPointCallback callback, void *userdata) +{ + int i; + + BVHNearestData data; + + //init data to search + data.tree = tree; + data.co = co; + + data.callback = callback; + data.userdata = userdata; + + for(i = data.tree->start_axis; i != data.tree->stop_axis; i++) + { + data.proj[i] = INPR(data.co, KDOP_AXES[i]); + } + + if(nearest) + { + memcpy( &data.nearest , nearest, sizeof(*nearest) ); + } + else + { + data.nearest.index = -1; + data.nearest.dist = FLT_MAX; + } + + //dfs search + dfs_find_nearest(&data, tree->nodes[tree->totleaf] ); + + //copy back results + if(nearest) + { + memcpy(nearest, &data.nearest, sizeof(*nearest)); + } + + return data.nearest.index; +} + + + +/* + * Ray cast + */ + +static float ray_nearest_hit(BVHRayCastData *data, BVHNode *node) +{ + int i; + const float *bv = node->bv; + + float low = 0, upper = data->hit.dist; + + for(i=0; i != 3; i++, bv += 2) + { + if(data->ray_dot_axis[i] == 0.0f) + { + //axis aligned ray + if(data->ray.origin[i] < bv[0] + || data->ray.origin[i] > bv[1]) + return FLT_MAX; + } + else + { + float ll = (bv[0] - data->ray.origin[i]) / data->ray_dot_axis[i]; + float lu = (bv[1] - data->ray.origin[i]) / data->ray_dot_axis[i]; + + if(data->ray_dot_axis[i] > 0) + { + if(ll > low) low = ll; + if(lu < upper) upper = lu; + } + else + { + if(lu > low) low = lu; + if(ll < upper) upper = ll; + } + + if(low > upper) return FLT_MAX; + } + } + return low; +} + +static void dfs_raycast(BVHRayCastData *data, BVHNode *node) +{ + int i; + + //ray-bv is really fast.. and simple tests revealed its worth to test it + //before calling the ray-primitive functions + float dist = ray_nearest_hit(data, node); + if(dist >= data->hit.dist) return; + + if(node->totnode == 0) + { + if(data->callback) + data->callback(data->userdata, node->index, &data->ray, &data->hit); + else + { + data->hit.index = node->index; + data->hit.dist = dist; + VECADDFAC(data->hit.co, data->ray.origin, data->ray.direction, dist); + } + } + else + { + //pick loop direction to dive into the tree (based on ray direction and split axis) + if(data->ray_dot_axis[ node->main_axis ] > 0) + { + for(i=0; i != node->totnode; i++) + { + dfs_raycast(data, node->children[i]); + } + } + else + { + for(i=node->totnode-1; i >= 0; i--) + { + dfs_raycast(data, node->children[i]); + } + } + } +} + + + +int BLI_bvhtree_ray_cast(BVHTree *tree, const float *co, const float *dir, BVHTreeRayHit *hit, BVHTree_RayCastCallback callback, void *userdata) +{ + int i; + BVHRayCastData data; + + data.tree = tree; + + data.callback = callback; + data.userdata = userdata; + + VECCOPY(data.ray.origin, co); + VECCOPY(data.ray.direction, dir); + + Normalize(data.ray.direction); + + for(i=0; i<3; i++) + { + data.ray_dot_axis[i] = INPR( data.ray.direction, KDOP_AXES[i]); + + if(fabs(data.ray_dot_axis[i]) < 1e-7) + data.ray_dot_axis[i] = 0.0; + } + + + if(hit) + memcpy( &data.hit, hit, sizeof(*hit) ); + else + { + data.hit.index = -1; + data.hit.dist = FLT_MAX; + } + + dfs_raycast(&data, tree->nodes[tree->totleaf]); + + + if(hit) + memcpy( hit, &data.hit, sizeof(*hit) ); + + return data.hit.index; +} + |