diff options
Diffstat (limited to 'source/blender/blenkernel/intern/cdderivedmesh.c')
-rw-r--r-- | source/blender/blenkernel/intern/cdderivedmesh.c | 327 |
1 files changed, 309 insertions, 18 deletions
diff --git a/source/blender/blenkernel/intern/cdderivedmesh.c b/source/blender/blenkernel/intern/cdderivedmesh.c index ca4a4b3196c..4369ef1a26d 100644 --- a/source/blender/blenkernel/intern/cdderivedmesh.c +++ b/source/blender/blenkernel/intern/cdderivedmesh.c @@ -2572,25 +2572,200 @@ void CDDM_calc_normals_tessface(DerivedMesh *dm) #if 1 /** + * Poly compare with vtargetmap + * Function used by #CDDM_merge_verts. + * The function compares poly_source after applying vtargetmap, with poly_target. + * The two polys are identical if they share the same vertices in the same order, or in reverse order, + * but starting position loopstart may be different. + * The function is called with direct_reverse=1 for same order (i.e. same normal), + * and may be called again with direct_reverse=-1 for reverse order. + * \return 1 if polys are identical, 0 if polys are different. + */ +static int cddm_poly_compare(MLoop *mloop_array, MPoly *mpoly_source, MPoly *mpoly_target, const int *vtargetmap, const int direct_reverse) +{ + int vert_source, first_vert_source, vert_target; + int i_loop_source; + int i_loop_target, i_loop_target_start, i_loop_target_offset, i_loop_target_adjusted; + bool compare_completed = false; + bool same_loops = false; + + MLoop *mloop_source, *mloop_target; + + BLI_assert(direct_reverse == 1 || direct_reverse == -1); + + i_loop_source = 0; + mloop_source = mloop_array + mpoly_source->loopstart; + vert_source = mloop_source->v; + + if (vtargetmap[vert_source] != -1) { + vert_source = vtargetmap[vert_source]; + } + else { + /* All source loop vertices should be mapped */ + BLI_assert(false); + } + + /* Find same vertex within mpoly_target's loops */ + mloop_target = mloop_array + mpoly_target->loopstart; + for (i_loop_target = 0; i_loop_target < mpoly_target->totloop; i_loop_target++, mloop_target++) { + if (mloop_target->v == vert_source) { + break; + } + } + + /* If same vertex not found, then polys cannot be equal */ + if (i_loop_target >= mpoly_target->totloop) { + return false; + } + + /* Now mloop_source and m_loop_target have one identical vertex */ + /* mloop_source is at position 0, while m_loop_target has advanced to find identical vertex */ + /* Go around the loop and check that all vertices match in same order */ + /* Skipping source loops when consecutive source vertices are mapped to same target vertex */ + + i_loop_target_start = i_loop_target; + i_loop_target_offset = 0; + first_vert_source = vert_source; + + compare_completed = false; + same_loops = false; + + while (!compare_completed) { + + vert_target = mloop_target->v; + + /* First advance i_loop_source, until it points to different vertex, after mapping applied */ + do { + i_loop_source++; + + if (i_loop_source == mpoly_source->totloop) { + /* End of loops for source, must match end of loop for target. */ + if (i_loop_target_offset == mpoly_target->totloop - 1) { + compare_completed = true; + same_loops = true; + break; /* Polys are identical */ + } + else { + compare_completed = true; + same_loops = false; + break; /* Polys are different */ + } + } + + mloop_source++; + vert_source = mloop_source->v; + + if (vtargetmap[vert_source] != -1) { + vert_source = vtargetmap[vert_source]; + } + else { + /* All source loop vertices should be mapped */ + BLI_assert(false); + } + + } while (vert_source == vert_target); + + if (compare_completed) { + break; + } + + /* Now advance i_loop_target as well */ + i_loop_target_offset++; + + if (i_loop_target_offset == mpoly_target->totloop) { + /* End of loops for target only, that means no match */ + /* except if all remaining source vertices are mapped to first target */ + for (; i_loop_source < mpoly_source->totloop; i_loop_source++, mloop_source++) { + vert_source = vtargetmap[mloop_source->v]; + if (vert_source != first_vert_source) { + compare_completed = true; + same_loops = false; + break; + } + } + if (!compare_completed) { + same_loops = true; + } + break; + } + + /* Adjust i_loop_target for cycling around and for direct/reverse order defined by delta = +1 or -1 */ + i_loop_target_adjusted = (i_loop_target_start + direct_reverse * i_loop_target_offset) % mpoly_target->totloop; + if (i_loop_target_adjusted < 0) { + i_loop_target_adjusted += mpoly_target->totloop; + } + mloop_target = mloop_array + mpoly_target->loopstart + i_loop_target_adjusted; + vert_target = mloop_target->v; + + if (vert_target != vert_source) { + same_loops = false; /* Polys are different */ + break; + } + } + return same_loops; +} + +/* Utility stuff for using GHash with polys */ + +typedef struct PolyKey { + int poly_index; /* index of the MPoly within the derived mesh */ + int totloops; /* number of loops in the poly */ + unsigned int hash_sum; /* Sum of all vertices indices */ + unsigned int hash_xor; /* Xor of all vertices indices */ +} PolyKey; + + +static unsigned int poly_gset_hash_fn(const void *key) +{ + const PolyKey *pk = key; + return pk->hash_sum; +} + +static int poly_gset_compare_fn(const void *k1, const void *k2) +{ + const PolyKey *pk1 = k1; + const PolyKey *pk2 = k2; + if ((pk1->hash_sum == pk2->hash_sum) && + (pk1->hash_xor == pk2->hash_xor) && + (pk1->totloops == pk2->totloops)) + { + /* Equality - note that this does not mean equality of polys */ + return 0; + } + else { + return 1; + } +} + +/** * Merge Verts * + * This frees dm, and returns a new one. + * * \param vtargetmap The table that maps vertices to target vertices. a value of -1 * indicates a vertex is a target, and is to be kept. * This array is aligned with 'dm->numVertData' * - * \param tot_vtargetmap The number of non '-1' values in vtargetmap. - * (not the size ) - * - * this frees dm, and returns a new one. + * \param tot_vtargetmap The number of non '-1' values in vtargetmap. (not the size) * - * note, CDDM_recalc_tessellation has to run on the returned DM if you want to access tessfaces. + * \param merge_mode enum with two modes. + * - #CDDM_MERGE_VERTS_DUMP_IF_MAPPED + * When called by the Mirror Modifier, + * In this mode it skips any faces that have all vertices merged (to avoid creating pairs + * of faces sharing the same set of vertices) + * - #CDDM_MERGE_VERTS_DUMP_IF_EQUAL + * When called by the Array Modifier, + * In this mode, faces where all vertices are merged are double-checked, + * to see whether all target vertices actually make up a poly already. + * Indeed it could be that all of a poly's vertices are merged, + * but merged to vertices that do not make up a single poly, + * in which case the original poly should not be dumped. + * Actually this later behavior could apply to the Mirror Modifier as well, but the additional checks are + * costly and not necessary in the case of mirror, because each vertex is only merged to its own mirror. * - * Note: This function is currently only used by the Mirror modifier, so it - * skips any faces that have all vertices merged (to avoid creating pairs - * of faces sharing the same set of vertices). If used elsewhere, it may - * be necessary to make this functionality optional. + * \note #CDDM_recalc_tessellation has to run on the returned DM if you want to access tessfaces. */ -DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int tot_vtargetmap) +DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int tot_vtargetmap, const int merge_mode) { // #define USE_LOOPS CDDerivedMesh *cddm = (CDDerivedMesh *)dm; @@ -2631,7 +2806,10 @@ DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int EdgeHash *ehash = BLI_edgehash_new_ex(__func__, totedge); int i, j, c; - + + PolyKey *poly_keys; + GSet *poly_gset = NULL; + STACK_INIT(oldv, totvert_final); STACK_INIT(olde, totedge); STACK_INIT(oldl, totloop); @@ -2673,10 +2851,9 @@ DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int med = cddm->medge; c = 0; for (i = 0; i < totedge; i++, med++) { - - if (LIKELY(med->v1 != med->v2)) { - const unsigned int v1 = (vtargetmap[med->v1] != -1) ? vtargetmap[med->v1] : med->v1; - const unsigned int v2 = (vtargetmap[med->v2] != -1) ? vtargetmap[med->v2] : med->v2; + const unsigned int v1 = (vtargetmap[med->v1] != -1) ? vtargetmap[med->v1] : med->v1; + const unsigned int v2 = (vtargetmap[med->v2] != -1) ? vtargetmap[med->v2] : med->v2; + if (LIKELY(v1 != v2)) { void **eh_p = BLI_edgehash_lookup_p(ehash, v1, v2); if (eh_p) { @@ -2695,13 +2872,49 @@ DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int } } + if (merge_mode == CDDM_MERGE_VERTS_DUMP_IF_EQUAL) { + /* In this mode, we need to determine, whenever a poly' vertices are all mapped */ + /* if the targets already make up a poly, in which case the new poly is dropped */ + /* This poly equality check is rather complex. We use a BLI_ghash to speed it up with a first level check */ + PolyKey *mpgh; + poly_keys = MEM_mallocN(sizeof(PolyKey) * totpoly, __func__); + poly_gset = BLI_gset_new_ex(poly_gset_hash_fn, poly_gset_compare_fn, __func__, totpoly); + /* Duplicates allowed because our compare function is not pure equality */ + BLI_gset_flag_set(poly_gset, GHASH_FLAG_ALLOW_DUPES); + + mp = cddm->mpoly; + mpgh = poly_keys; + for (i = 0; i < totpoly; i++, mp++, mpgh++) { + mpgh->poly_index = i; + mpgh->totloops = mp->totloop; + ml = cddm->mloop + mp->loopstart; + mpgh->hash_sum = mpgh->hash_xor = 0; + for (j = 0; j < mp->totloop; j++, ml++) { + mpgh->hash_sum += ml->v; + mpgh->hash_xor ^= ml->v; + } + BLI_gset_insert(poly_gset, mpgh); + } + + if (cddm->pmap) { + MEM_freeN(cddm->pmap); + MEM_freeN(cddm->pmap_mem); + } + /* Can we optimise by reusing an old pmap ? How do we know an old pmap is stale ? */ + /* When called by MOD_array.c, the cddm has just been created, so it has no valid pmap. */ + BKE_mesh_vert_poly_map_create(&cddm->pmap, &cddm->pmap_mem, + cddm->mpoly, cddm->mloop, + totvert, totpoly, totloop); + } /* done preparing for fast poly compare */ + + mp = cddm->mpoly; for (i = 0; i < totpoly; i++, mp++) { MPoly *mp_new; ml = cddm->mloop + mp->loopstart; - /* skip faces with all vertices merged */ + /* check faces with all vertices merged */ { bool all_vertices_merged = true; @@ -2713,16 +2926,86 @@ DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int } if (UNLIKELY(all_vertices_merged)) { - continue; + if (merge_mode == CDDM_MERGE_VERTS_DUMP_IF_MAPPED) { + /* In this mode, all vertices merged is enough to dump face */ + continue; + } + else if (merge_mode == CDDM_MERGE_VERTS_DUMP_IF_EQUAL) { + /* Additional condition for face dump: target vertices must make up an identical face */ + /* The test has 2 steps: (1) first step is fast ghash lookup, but not failproof */ + /* (2) second step is thorough but more costly poly compare */ + int i_poly, v_target, v_prev; + bool found = false; + PolyKey pkey; + + /* Use poly_gset for fast (although not 100% certain) identification of same poly */ + /* First, make up a poly_summary structure */ + ml = cddm->mloop + mp->loopstart; + pkey.hash_sum = pkey.hash_xor = 0; + pkey.totloops = 0; + v_prev = vtargetmap[(ml + mp->totloop -1)->v]; /* since it loops around, the prev of first is the last */ + for (j = 0; j < mp->totloop; j++, ml++) { + v_target = vtargetmap[ml->v]; /* Cannot be -1, they are all mapped */ + if (v_target == v_prev) { + /* consecutive vertices in loop map to the same target: discard */ + /* but what about last to first ? */ + continue; + } + pkey.hash_sum += v_target; + pkey.hash_xor ^= v_target; + pkey.totloops++; + v_prev = v_target; + } + if (BLI_gset_haskey(poly_gset, &pkey)) { + + /* There might be a poly that matches this one. + * We could just leave it there and say there is, and do a "continue". + * ... but we are checking whether there is an exact poly match. + * It's not so costly in terms of CPU since it's very rare, just a lot of complex code. + */ + + /* Consider current loop again */ + ml = cddm->mloop + mp->loopstart; + /* Consider the target of the loop's first vert */ + v_target = vtargetmap[ml->v]; + /* Now see if v_target belongs to a poly that shares all vertices with source poly, + * in same order, or reverse order */ + + for (i_poly = 0; i_poly < cddm->pmap[v_target].count; i_poly++) { + MPoly *target_poly = cddm->mpoly + *(cddm->pmap[v_target].indices + i_poly); + + if (cddm_poly_compare(cddm->mloop, mp, target_poly, vtargetmap, +1) || + cddm_poly_compare(cddm->mloop, mp, target_poly, vtargetmap, -1)) + { + found = true; + break; + } + } + if (found) { + /* Current poly's vertices are mapped to a poly that is strictly identical */ + /* Current poly is dumped */ + continue; + } + } + } } } + + /* Here either the poly's vertices were not all merged + * or they were all merged, but targets do not make up an identical poly, + * the poly is retained. + */ ml = cddm->mloop + mp->loopstart; c = 0; for (j = 0; j < mp->totloop; j++, ml++) { + unsigned int v1, v2; + med = cddm->medge + ml->e; - if (LIKELY(med->v1 != med->v2)) { + v1 = (vtargetmap[med->v1] != -1) ? vtargetmap[med->v1] : med->v1; + v2 = (vtargetmap[med->v2] != -1) ? vtargetmap[med->v2] : med->v2; + if (LIKELY(v1 != v2)) { #ifdef USE_LOOPS newl[j + mp->loopstart] = STACK_SIZE(mloop); #endif @@ -2742,6 +3025,14 @@ DerivedMesh *CDDM_merge_verts(DerivedMesh *dm, const int *vtargetmap, const int mp_new->loopstart = STACK_SIZE(mloop) - c; STACK_PUSH(oldp, i); + } /* end of the loop that tests polys */ + + + if (poly_gset) { + // printf("hash quality %.6f\n", BLI_gset_calc_quality(poly_gset)); + + BLI_gset_free(poly_gset, NULL); + MEM_freeN(poly_keys); } /*create new cddm*/ |