MOD_boolean_util.c

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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): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 * CSG operations. 
 */

#include "DNA_material_types.h"
#include "DNA_mesh_types.h"
#include "DNA_meshdata_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"

#include "MEM_guardedalloc.h"

#include "BLI_math.h"
#include "BLI_utildefines.h"
#include "BLI_listbase.h"
#include "BLI_ghash.h"

#include "BKE_cdderivedmesh.h"
#include "BKE_depsgraph.h"
#include "BKE_material.h"
#include "BKE_mesh.h"
#include "BKE_object.h"

#include "CSG_BooleanOps.h"

#include "MOD_boolean_util.h"

typedef struct {
    DerivedMesh *dm;
    Object *ob;
    int pos;
} VertexIt;

static void VertexIt_Destruct(CSG_VertexIteratorDescriptor * iterator)
{
    if (iterator->it) {
        // deallocate memory for iterator
        MEM_freeN(iterator->it);
        iterator->it = 0;
    }
    iterator->Done = NULL;
    iterator->Fill = NULL;
    iterator->Reset = NULL;
    iterator->Step = NULL;
    iterator->num_elements = 0;

}       

static int VertexIt_Done(CSG_IteratorPtr it)
{
    VertexIt * iterator = (VertexIt *)it;
    return(iterator->pos >= iterator->dm->getNumVerts(iterator->dm));
}

static void VertexIt_Fill(CSG_IteratorPtr it, CSG_IVertex *vert)
{
    VertexIt * iterator = (VertexIt *)it;
    MVert *verts = iterator->dm->getVertArray(iterator->dm);

    float global_pos[3];

    /* boolean happens in global space, transform both with obmat */
    mul_v3_m4v3(
        global_pos,
        iterator->ob->obmat, 
        verts[iterator->pos].co
    );

    vert->position[0] = global_pos[0];
    vert->position[1] = global_pos[1];
    vert->position[2] = global_pos[2];
}

static void VertexIt_Step(CSG_IteratorPtr it)
{
    VertexIt * iterator = (VertexIt *)it;
    iterator->pos ++;
} 
 
static void VertexIt_Reset(CSG_IteratorPtr it)
{
    VertexIt * iterator = (VertexIt *)it;
    iterator->pos = 0;
}

static void VertexIt_Construct(CSG_VertexIteratorDescriptor *output, DerivedMesh *dm, Object *ob)
{

    VertexIt *it;
    if (output == 0) return;

    // allocate some memory for blender iterator
    it = (VertexIt *)(MEM_mallocN(sizeof(VertexIt),"Boolean_VIt"));
    if (it == 0) {
        return;
    }
    // assign blender specific variables
    it->dm = dm;
    it->ob = ob; // needed for obmat transformations 
    
    it->pos = 0;

     // assign iterator function pointers.
    output->Step = VertexIt_Step;
    output->Fill = VertexIt_Fill;
    output->Done = VertexIt_Done;
    output->Reset = VertexIt_Reset;
    output->num_elements = it->dm->getNumVerts(it->dm);
    output->it = it;
}

typedef struct {
    DerivedMesh *dm;
    int pos;
    int offset;
    int flip;
} FaceIt;

static void FaceIt_Destruct(CSG_FaceIteratorDescriptor * iterator)
{
    MEM_freeN(iterator->it);
    iterator->Done = NULL;
    iterator->Fill = NULL;
    iterator->Reset = NULL;
    iterator->Step = NULL;
    iterator->num_elements = 0;
}

static int FaceIt_Done(CSG_IteratorPtr it)
{
    // assume CSG_IteratorPtr is of the correct type.
    FaceIt * iterator = (FaceIt *)it;
    return(iterator->pos >= iterator->dm->getNumFaces(iterator->dm));
}

static void FaceIt_Fill(CSG_IteratorPtr it, CSG_IFace *face)
{
    // assume CSG_IteratorPtr is of the correct type.
    FaceIt *face_it = (FaceIt *)it;
    MFace *mfaces = face_it->dm->getFaceArray(face_it->dm);
    MFace *mface = &mfaces[face_it->pos];

    /* reverse face vertices if necessary */
    face->vertex_index[1] = mface->v2;
    if( face_it->flip == 0 ) {
    face->vertex_index[0] = mface->v1;
    face->vertex_index[2] = mface->v3;
    } else {
        face->vertex_index[2] = mface->v1;
        face->vertex_index[0] = mface->v3;
    }
    if (mface->v4) {
        face->vertex_index[3] = mface->v4;
        face->vertex_number = 4;
    } else {
        face->vertex_number = 3;
    }

    face->orig_face = face_it->offset + face_it->pos;
}

static void FaceIt_Step(CSG_IteratorPtr it)
{
    FaceIt * face_it = (FaceIt *)it;        
    face_it->pos ++;
}

static void FaceIt_Reset(CSG_IteratorPtr it)
{
    FaceIt * face_it = (FaceIt *)it;        
    face_it->pos = 0;
}   

static void FaceIt_Construct(
    CSG_FaceIteratorDescriptor *output, DerivedMesh *dm, int offset, Object *ob)
{
    FaceIt *it;
    if (output == 0) return;

    // allocate some memory for blender iterator
    it = (FaceIt *)(MEM_mallocN(sizeof(FaceIt),"Boolean_FIt"));
    if (it == 0) {
        return ;
    }
    // assign blender specific variables
    it->dm = dm;
    it->offset = offset;
    it->pos = 0;

    /* determine if we will need to reverse order of face vertices */
    if (ob->size[0] < 0.0f) {
        if (ob->size[1] < 0.0f && ob->size[2] < 0.0f) {
            it->flip = 1;
        } else if (ob->size[1] >= 0.0f && ob->size[2] >= 0.0f) {
            it->flip = 1;
        } else {
            it->flip = 0;
        }
    } else {
        if (ob->size[1] < 0.0f && ob->size[2] < 0.0f) {
            it->flip = 0;
        } else if (ob->size[1] >= 0.0f && ob->size[2] >= 0.0f) {
            it->flip = 0;
        } else {
            it->flip = 1;
        }
    }

    // assign iterator function pointers.
    output->Step = FaceIt_Step;
    output->Fill = FaceIt_Fill;
    output->Done = FaceIt_Done;
    output->Reset = FaceIt_Reset;
    output->num_elements = it->dm->getNumFaces(it->dm);
    output->it = it;
}

static Object *AddNewBlenderMesh(Scene *scene, Base *base)
{
    // This little function adds a new mesh object to the blender object list
    // It uses ob to duplicate data as this seems to be easier than creating
    // a new one. This new oject contains no faces nor vertices.
    Mesh *old_me;
    Base *basen;
    Object *ob_new;

    // now create a new blender object.
    // duplicating all the settings from the previous object
    // to the new one.
    ob_new= copy_object(base->object);

    // Ok we don't want to use the actual data from the
    // last object, the above function incremented the 
    // number of users, so decrement it here.
    old_me= ob_new->data;
    old_me->id.us--;

    // Now create a new base to add into the linked list of 
    // vase objects.
    
    basen= MEM_mallocN(sizeof(Base), "duplibase");
    *basen= *base;
    BLI_addhead(&scene->base, basen);   /* addhead: anders oneindige lus */
    basen->object= ob_new;
    basen->flag &= ~SELECT;
                
    // Initialize the mesh data associated with this object.                        
    ob_new->data= add_mesh("Mesh");

    // Finally assign the object type.
    ob_new->type= OB_MESH;

    return ob_new;
}

static void InterpCSGFace(
    DerivedMesh *dm, DerivedMesh *orig_dm, int index, int orig_index, int nr,
    float mapmat[][4])
{
    float obco[3], *co[4], *orig_co[4], w[4][4];
    MFace *mface, *orig_mface;
    int j;

    mface = CDDM_get_face(dm, index);
    orig_mface = orig_dm->getFaceArray(orig_dm) + orig_index;

    // get the vertex coordinates from the original mesh
    orig_co[0] = (orig_dm->getVertArray(orig_dm) + orig_mface->v1)->co;
    orig_co[1] = (orig_dm->getVertArray(orig_dm) + orig_mface->v2)->co;
    orig_co[2] = (orig_dm->getVertArray(orig_dm) + orig_mface->v3)->co;
    orig_co[3] = (orig_mface->v4)? (orig_dm->getVertArray(orig_dm) + orig_mface->v4)->co: NULL;

    // get the vertex coordinates from the new derivedmesh
    co[0] = CDDM_get_vert(dm, mface->v1)->co;
    co[1] = CDDM_get_vert(dm, mface->v2)->co;
    co[2] = CDDM_get_vert(dm, mface->v3)->co;
    co[3] = (nr == 4)? CDDM_get_vert(dm, mface->v4)->co: NULL;

    for (j = 0; j < nr; j++) {
        // get coordinate into the space of the original mesh
        if (mapmat)
            mul_v3_m4v3(obco, mapmat, co[j]);
        else
            copy_v3_v3(obco, co[j]);

        interp_weights_face_v3( w[j],orig_co[0], orig_co[1], orig_co[2], orig_co[3], obco);
    }

    CustomData_interp(&orig_dm->faceData, &dm->faceData, &orig_index, NULL, (float*)w, 1, index);
}

/* Iterate over the CSG Output Descriptors and create a new DerivedMesh
   from them */
static DerivedMesh *ConvertCSGDescriptorsToDerivedMesh(
    CSG_FaceIteratorDescriptor *face_it,
    CSG_VertexIteratorDescriptor *vertex_it,
    float parinv[][4],
    float mapmat[][4],
    Material **mat,
    int *totmat,
    DerivedMesh *dm1,
    Object *ob1,
    DerivedMesh *dm2,
    Object *ob2)
{
    DerivedMesh *result, *orig_dm;
    GHash *material_hash = NULL;
    Mesh *me1= (Mesh*)ob1->data;
    Mesh *me2= (Mesh*)ob2->data;
    int i;

    // create a new DerivedMesh
    result = CDDM_new(vertex_it->num_elements, 0, face_it->num_elements);
    CustomData_merge(&dm1->faceData, &result->faceData, CD_MASK_DERIVEDMESH,
                      CD_DEFAULT, face_it->num_elements); 
    CustomData_merge(&dm2->faceData, &result->faceData, CD_MASK_DERIVEDMESH,
                      CD_DEFAULT, face_it->num_elements); 

    // step through the vertex iterators:
    for (i = 0; !vertex_it->Done(vertex_it->it); i++) {
        CSG_IVertex csgvert;
        MVert *mvert = CDDM_get_vert(result, i);

        // retrieve a csg vertex from the boolean module
        vertex_it->Fill(vertex_it->it, &csgvert);
        vertex_it->Step(vertex_it->it);

        // we have to map the vertex coordinates back in the coordinate frame
        // of the resulting object, since it was computed in world space
        mul_v3_m4v3(mvert->co, parinv, csgvert.position);
    }

    // a hash table to remap materials to indices
    if (mat) {
        material_hash = BLI_ghash_new(BLI_ghashutil_ptrhash, BLI_ghashutil_ptrcmp, "CSG_mat gh");
        *totmat = 0;
    }

    // step through the face iterators
    for(i = 0; !face_it->Done(face_it->it); i++) {
        Mesh *orig_me;
        Object *orig_ob;
        Material *orig_mat;
        CSG_IFace csgface;
        MFace *mface;
        int orig_index, mat_nr;

        // retrieve a csg face from the boolean module
        face_it->Fill(face_it->it, &csgface);
        face_it->Step(face_it->it);

        // find the original mesh and data
        orig_ob = (csgface.orig_face < dm1->getNumFaces(dm1))? ob1: ob2;
        orig_dm = (csgface.orig_face < dm1->getNumFaces(dm1))? dm1: dm2;
        orig_me = (orig_ob == ob1)? me1: me2;
        orig_index = (orig_ob == ob1)? csgface.orig_face: csgface.orig_face - dm1->getNumFaces(dm1);

        // copy all face layers, including mface
        CustomData_copy_data(&orig_dm->faceData, &result->faceData, orig_index, i, 1);

        // set mface
        mface = CDDM_get_face(result, i);
        mface->v1 = csgface.vertex_index[0];
        mface->v2 = csgface.vertex_index[1];
        mface->v3 = csgface.vertex_index[2];
        mface->v4 = (csgface.vertex_number == 4)? csgface.vertex_index[3]: 0;

        // set material, based on lookup in hash table
        orig_mat= give_current_material(orig_ob, mface->mat_nr+1);

        if (mat && orig_mat) {
            if (!BLI_ghash_haskey(material_hash, orig_mat)) {
                mat[*totmat] = orig_mat;
                mat_nr = mface->mat_nr = (*totmat)++;
                BLI_ghash_insert(material_hash, orig_mat, SET_INT_IN_POINTER(mat_nr));
            }
            else
                mface->mat_nr = GET_INT_FROM_POINTER(BLI_ghash_lookup(material_hash, orig_mat));
        }
        else
            mface->mat_nr = 0;

        InterpCSGFace(result, orig_dm, i, orig_index, csgface.vertex_number,
                      (orig_me == me2)? mapmat: NULL);

        test_index_face(mface, &result->faceData, i, csgface.vertex_number);
    }

    if (material_hash)
        BLI_ghash_free(material_hash, NULL, NULL);

    CDDM_calc_edges(result);
    CDDM_calc_normals(result);

    return result;
}
    
static void BuildMeshDescriptors(
    struct DerivedMesh *dm,
    struct Object *ob,
    int face_offset,
    struct CSG_FaceIteratorDescriptor * face_it,
    struct CSG_VertexIteratorDescriptor * vertex_it)
{
    VertexIt_Construct(vertex_it,dm, ob);
    FaceIt_Construct(face_it,dm,face_offset,ob);
}
    
static void FreeMeshDescriptors(
    struct CSG_FaceIteratorDescriptor *face_it,
    struct CSG_VertexIteratorDescriptor *vertex_it)
{
    VertexIt_Destruct(vertex_it);
    FaceIt_Destruct(face_it);
}

static DerivedMesh *NewBooleanDerivedMesh_intern(
    DerivedMesh *dm, struct Object *ob, DerivedMesh *dm_select, struct Object *ob_select,
    int int_op_type, Material **mat, int *totmat)
{

    float inv_mat[4][4];
    float map_mat[4][4];

    DerivedMesh *result = NULL;

    if (dm == NULL || dm_select == NULL) return 0;
    if (!dm->getNumFaces(dm) || !dm_select->getNumFaces(dm_select)) return 0;

    // we map the final object back into ob's local coordinate space. For this
    // we need to compute the inverse transform from global to ob (inv_mat),
    // and the transform from ob to ob_select for use in interpolation (map_mat)
    invert_m4_m4(inv_mat, ob->obmat);
    mult_m4_m4m4(map_mat, inv_mat, ob_select->obmat);
    invert_m4_m4(inv_mat, ob_select->obmat);

    {
        // interface with the boolean module:
        //
        // the idea is, we pass the boolean module verts and faces using the
        // provided descriptors. once the boolean operation is performed, we
        // get back output descriptors, from which we then build a DerivedMesh

        CSG_VertexIteratorDescriptor vd_1, vd_2;
        CSG_FaceIteratorDescriptor fd_1, fd_2;
        CSG_OperationType op_type;
        CSG_BooleanOperation *bool_op;

        // work out the operation they chose and pick the appropriate 
        // enum from the csg module.
        switch (int_op_type) {
            case 1 : op_type = e_csg_intersection; break;
            case 2 : op_type = e_csg_union; break;
            case 3 : op_type = e_csg_difference; break;
            case 4 : op_type = e_csg_classify; break;
            default : op_type = e_csg_intersection;
        }
        
        BuildMeshDescriptors(dm_select, ob_select, 0, &fd_1, &vd_1);
        BuildMeshDescriptors(dm, ob, dm_select->getNumFaces(dm_select) , &fd_2, &vd_2);

        bool_op = CSG_NewBooleanFunction();

        // perform the operation
        if (CSG_PerformBooleanOperation(bool_op, op_type, fd_1, vd_1, fd_2, vd_2)) {
            CSG_VertexIteratorDescriptor vd_o;
            CSG_FaceIteratorDescriptor fd_o;

            CSG_OutputFaceDescriptor(bool_op, &fd_o);
            CSG_OutputVertexDescriptor(bool_op, &vd_o);

            // iterate through results of operation and insert
            // into new object
            result = ConvertCSGDescriptorsToDerivedMesh(
                &fd_o, &vd_o, inv_mat, map_mat, mat, totmat, dm_select, ob_select, dm, ob);

            // free up the memory
            CSG_FreeVertexDescriptor(&vd_o);
            CSG_FreeFaceDescriptor(&fd_o);
        }
        else
            printf("Unknown internal error in boolean");

        CSG_FreeBooleanOperation(bool_op);

        FreeMeshDescriptors(&fd_1, &vd_1);
        FreeMeshDescriptors(&fd_2, &vd_2);
    }

    return result;
}

int NewBooleanMesh(Scene *scene, Base *base, Base *base_select, int int_op_type)
{
    Mesh *me_new;
    int a, maxmat, totmat= 0;
    Object *ob_new, *ob, *ob_select;
    Material **mat;
    DerivedMesh *result;
    DerivedMesh *dm_select;
    DerivedMesh *dm;

    ob= base->object;
    ob_select= base_select->object;

    dm = mesh_get_derived_final(scene, ob, CD_MASK_BAREMESH);
    dm_select = mesh_create_derived_view(scene, ob_select, 0); // no modifiers in editmode ??

    maxmat= ob->totcol + ob_select->totcol;
    mat= (Material**)MEM_mallocN(sizeof(Material*)*maxmat, "NewBooleanMeshMat");
    
    /* put some checks in for nice user feedback */
    if (dm == NULL || dm_select == NULL) return 0;
    if (!dm->getNumFaces(dm) || !dm_select->getNumFaces(dm_select))
    {
        MEM_freeN(mat);
        return -1;
    }
    
    result= NewBooleanDerivedMesh_intern(dm, ob, dm_select, ob_select, int_op_type, mat, &totmat);

    if (result == NULL) {
        MEM_freeN(mat);
        return 0;
    }

    /* create a new blender mesh object - using 'base' as  a template */
    ob_new= AddNewBlenderMesh(scene, base_select);
    me_new= ob_new->data;

    DM_to_mesh(result, me_new);
    result->release(result);

    dm->release(dm);
    dm_select->release(dm_select);

    /* add materials to object */
    for (a = 0; a < totmat; a++)
        assign_material(ob_new, mat[a], a+1);

    MEM_freeN(mat);

    /* update dag */
    DAG_id_tag_update(&ob_new->id, OB_RECALC_DATA);

    return 1;
}

DerivedMesh *NewBooleanDerivedMesh(DerivedMesh *dm, struct Object *ob, DerivedMesh *dm_select, struct Object *ob_select,
                                   int int_op_type)
{
    return NewBooleanDerivedMesh_intern(dm, ob, dm_select, ob_select, int_op_type, NULL, NULL);
}