diff options
Diffstat (limited to 'source/blender/bmesh/intern/bmesh_mesh_convert.cc')
-rw-r--r-- | source/blender/bmesh/intern/bmesh_mesh_convert.cc | 455 |
1 files changed, 290 insertions, 165 deletions
diff --git a/source/blender/bmesh/intern/bmesh_mesh_convert.cc b/source/blender/bmesh/intern/bmesh_mesh_convert.cc index 40a82fdd96f..d5a5c08752d 100644 --- a/source/blender/bmesh/intern/bmesh_mesh_convert.cc +++ b/source/blender/bmesh/intern/bmesh_mesh_convert.cc @@ -54,6 +54,19 @@ * * This has the effect from the users POV of leaving the mesh un-touched, * and only editing the active shape key-block. + * + * \subsection other_notes Other Notes + * + * Other details noted here which might not be so obvious: + * + * - The #CD_SHAPEKEY layer is only used in edit-mode, + * and the #Mesh.key is only used in object-mode. + * Although the #CD_SHAPEKEY custom-data layer is converted into #Key data-blocks for each + * undo-step while in edit-mode. + * - The #CD_SHAPE_KEYINDEX layer is used to check if vertices existed when entering edit-mode. + * Values of the indices are only used for shape-keys when the #CD_SHAPEKEY layer can't be found, + * allowing coordinates from the #Key to be used to prevent data-loss. + * These indices are also used to maintain correct indices for hook modifiers and vertex parents. */ #include "DNA_key_types.h" @@ -84,6 +97,10 @@ #include "bmesh.h" #include "intern/bmesh_private.h" /* For element checking. */ +#include "CLG_log.h" + +static CLG_LogRef LOG = {"bmesh.mesh.convert"}; + using blender::Array; using blender::IndexRange; using blender::Span; @@ -553,8 +570,89 @@ static BMVert **bm_to_mesh_vertex_map(BMesh *bm, int ototvert) return vertMap; } +/* -------------------------------------------------------------------- */ +/** \name Edit-Mesh to Shape Key Conversion + * + * There are some details relating to using data from shape keys that need to be + * considered carefully for shape key synchronization logic. + * + * Key Block Usage + * *************** + * + * Key blocks (data in #Mesh.key must be used carefully). + * + * They can be used to query which key blocks are relative to the basis + * since it's not possible to add/remove/reorder key blocks while in edit-mode. + * + * Key Block Coordinates + * ===================== + * + * Key blocks locations must *not* be used. This was done from v2.67 to 3.0, + * causing bugs T35170 & T44415. + * + * Shape key synchronizing could work under the assumption that the key-block is + * fixed-in-place when entering edit-mode allowing them to be used as a reference when exiting. + * It often does work but isn't reliable since for e.g. rendering may flush changes + * from the edit-mesh to the key-block (there are a handful of other situations where + * changes may be flushed, see #ED_editors_flush_edits and related functions). + * When using undo, it's not known if the data in key-block is from the past or future, + * so just don't use this data as it causes pain and suffering for users and developers alike. + * + * Instead, use the shape-key values stored in #CD_SHAPEKEY since they are reliably + * based on the original locations, unless explicitly manipulated. + * It's important to write the final shape-key values back to the #CD_SHAPEKEY so applying + * the difference between the original-basis and the new coordinates isn't done multiple times. + * Therefore #ED_editors_flush_edits and other flushing calls will update both the #Mesh.key + * and the edit-mode #CD_SHAPEKEY custom-data layers. + * + * WARNING: There is an exception to the rule of ignoring coordinates in the destination: + * that is when shape-key data in `bm` can't be found (which is itself an error/exception). + * In this case our own rule is violated as the alternative is loosing the shape-data entirely. + * + * Flushing Coordinates Back to the #BMesh + * --------------------------------------- + * + * The edit-mesh may be flushed back to the #Mesh and #Key used to generate it. + * When this is done, the new values are written back to the #BMesh's #CD_SHAPEKEY as well. + * This is necessary when editing basis-shapes so the difference in shape keys + * is not applied multiple times. If it were important to avoid it could be skipped while + * exiting edit-mode (as the entire #BMesh is freed in that case), however it's just copying + * back a `float[3]` so the work to check if it's necessary isn't worth the overhead. + * + * In general updating the #BMesh's #CD_SHAPEKEY makes shake-key logic easier to reason about + * since it means flushing data back to the mesh has the same behavior as exiting and entering + * edit-mode (a more common operation). Meaning there is one less corner-case to have to consider. + * + * Exceptional Cases + * ***************** + * + * There are some situations that should not happen in typical usage but are + * still handled in this code, since failure to handle them could loose user-data. + * These could be investigated further since if they never happen in practice, + * we might consider removing them. However, the possibility of an mesh directly + * being modified by Python or some other low level logic that changes key-blocks + * means there is a potential this to happen so keeping code to these cases remain supported. + * + * - Custom Data & Mesh Key Block Synchronization. + * Key blocks in `me->key->block` should always have an associated + * #CD_SHAPEKEY layer in `bm->vdata`. + * If they don't there are two fall-backs for setting the location, + * - Use the value from the original shape key + * WARNING: this is technically incorrect! (see note on "Key Block Usage"). + * - Use the current vertex location, + * Also not correct but it's better then having it zeroed for e.g. + * + * - Missing key-index layer. + * In this case the basis key wont apply it's deltas to other keys and in the case + * a shape-key layer is missing, its coordinates will be initialized from the edit-mesh + * vertex locations instead of attempting to remap the shape-keys coordinates. + * + * \note These cases are considered abnormal and shouldn't occur in typical usage. + * A warning is logged in this case to help troubleshooting bugs with shape-keys. + * \{ */ + /** - * Returns custom-data shapekey index from a keyblock or -1 + * Returns custom-data shape-key index from a key-block or -1 * \note could split this out into a more generic function. */ static int bm_to_mesh_shape_layer_index_from_kb(BMesh *bm, KeyBlock *currkey) @@ -573,6 +671,196 @@ static int bm_to_mesh_shape_layer_index_from_kb(BMesh *bm, KeyBlock *currkey) return -1; } +/** + * Update `key` with shape key data stored in `bm`. + * + * \param bm: The source BMesh. + * \param key: The destination key. + * \param mvert: The destination vertex array (in some situations it's coordinates are updated). + */ +static void bm_to_mesh_shape(BMesh *bm, Key *key, MVert *mvert) +{ + KeyBlock *actkey = static_cast<KeyBlock *>(BLI_findlink(&key->block, bm->shapenr - 1)); + + /* It's unlikely this ever remains false, check for correctness. */ + bool actkey_has_layer = false; + + /* Go through and find any shape-key custom-data layers + * that might not have corresponding KeyBlocks, and add them if necessary. */ + for (int i = 0; i < bm->vdata.totlayer; i++) { + if (bm->vdata.layers[i].type != CD_SHAPEKEY) { + continue; + } + + KeyBlock *currkey; + for (currkey = (KeyBlock *)key->block.first; currkey; currkey = currkey->next) { + if (currkey->uid == bm->vdata.layers[i].uid) { + break; + } + } + + if (currkey) { + if (currkey == actkey) { + actkey_has_layer = true; + } + } + else { + currkey = BKE_keyblock_add(key, bm->vdata.layers[i].name); + currkey->uid = bm->vdata.layers[i].uid; + } + } + + const int cd_shape_keyindex_offset = CustomData_get_offset(&bm->vdata, CD_SHAPE_KEYINDEX); + BMIter iter; + BMVert *eve; + float(*ofs)[3] = nullptr; + + /* Editing the basis key updates others. */ + if ((key->type == KEY_RELATIVE) && + /* The shape-key coordinates used from entering edit-mode are used. */ + (actkey_has_layer == true) && + /* Original key-indices are only used to check the vertex existed when entering edit-mode. */ + (cd_shape_keyindex_offset != -1) && + /* Offsets are only needed if the current shape is a basis for others. */ + BKE_keyblock_is_basis(key, bm->shapenr - 1)) { + + BLI_assert(actkey != nullptr); /* Assured by `actkey_has_layer` check. */ + const int actkey_uuid = bm_to_mesh_shape_layer_index_from_kb(bm, actkey); + + /* Since `actkey_has_layer == true`, this must never fail. */ + BLI_assert(actkey_uuid != -1); + + const int cd_shape_offset = CustomData_get_n_offset(&bm->vdata, CD_SHAPEKEY, actkey_uuid); + + ofs = static_cast<float(*)[3]>(MEM_mallocN(sizeof(float[3]) * bm->totvert, __func__)); + int i; + BM_ITER_MESH_INDEX (eve, &iter, bm, BM_VERTS_OF_MESH, i) { + const int keyi = BM_ELEM_CD_GET_INT(eve, cd_shape_keyindex_offset); + /* Check the vertex existed when entering edit-mode (otherwise don't apply an offset). */ + if (keyi != ORIGINDEX_NONE) { + float *co_orig = (float *)BM_ELEM_CD_GET_VOID_P(eve, cd_shape_offset); + /* Could use 'eve->co' or the destination #MVert.co, they're the same at this point. */ + sub_v3_v3v3(ofs[i], eve->co, co_orig); + } + else { + /* If there are new vertices in the mesh, we can't propagate the offset + * because it will only work for the existing vertices and not the new + * ones, creating a mess when doing e.g. subdivide + translate. */ + MEM_freeN(ofs); + ofs = nullptr; + break; + } + } + } + + LISTBASE_FOREACH (KeyBlock *, currkey, &key->block) { + int keyi; + float(*currkey_data)[3]; + + const int currkey_uuid = bm_to_mesh_shape_layer_index_from_kb(bm, currkey); + const int cd_shape_offset = (currkey_uuid == -1) ? + -1 : + CustomData_get_n_offset(&bm->vdata, CD_SHAPEKEY, currkey_uuid); + + /* Common case, the layer data is available, use it where possible. */ + if (cd_shape_offset != -1) { + const bool apply_offset = (ofs != nullptr) && (currkey != actkey) && + (bm->shapenr - 1 == currkey->relative); + + if (currkey->data && (currkey->totelem == bm->totvert)) { + /* Use memory in-place. */ + } + else { + currkey->data = MEM_reallocN(currkey->data, key->elemsize * bm->totvert); + currkey->totelem = bm->totvert; + } + currkey_data = (float(*)[3])currkey->data; + + int i; + BM_ITER_MESH_INDEX (eve, &iter, bm, BM_VERTS_OF_MESH, i) { + float *co_orig = (float *)BM_ELEM_CD_GET_VOID_P(eve, cd_shape_offset); + + if (currkey == actkey) { + copy_v3_v3(currkey_data[i], eve->co); + + if (actkey != key->refkey) { + /* Without this, the real mesh coordinates (uneditable) as soon as you create + * the Basis shape, see: T30771 for details. */ + if (cd_shape_keyindex_offset != -1) { + keyi = BM_ELEM_CD_GET_INT(eve, cd_shape_keyindex_offset); + if (keyi != ORIGINDEX_NONE) { + copy_v3_v3(mvert[i].co, co_orig); + } + } + } + } + else { + copy_v3_v3(currkey_data[i], co_orig); + } + + /* Propagate edited basis offsets to other shapes. */ + if (apply_offset) { + add_v3_v3(currkey_data[i], ofs[i]); + } + + /* Apply back new coordinates shape-keys that have offset into #BMesh. + * Otherwise, in case we call again #BM_mesh_bm_to_me on same #BMesh, + * we'll apply diff from previous call to #BM_mesh_bm_to_me, + * to shape-key values from original creation of the #BMesh. See T50524. */ + copy_v3_v3(co_orig, currkey_data[i]); + } + } + else { + /* No original layer data, use fallback information. */ + if (currkey->data && (cd_shape_keyindex_offset != -1)) { + CLOG_WARN(&LOG, + "Found shape-key but no CD_SHAPEKEY layers to read from, " + "using existing shake-key data where possible"); + } + else { + CLOG_WARN(&LOG, + "Found shape-key but no CD_SHAPEKEY layers to read from, " + "using basis shape-key data"); + } + + currkey_data = static_cast<float(*)[3]>( + MEM_mallocN(key->elemsize * bm->totvert, "currkey->data")); + + int i; + BM_ITER_MESH_INDEX (eve, &iter, bm, BM_VERTS_OF_MESH, i) { + + if ((currkey->data != nullptr) && (cd_shape_keyindex_offset != -1) && + ((keyi = BM_ELEM_CD_GET_INT(eve, cd_shape_keyindex_offset)) != ORIGINDEX_NONE) && + (keyi < currkey->totelem)) { + /* Reconstruct keys via vertices original key indices. + * WARNING(@campbellbarton): `currkey->data` is known to be unreliable as the edit-mesh + * coordinates may be flushed back to the shape-key when exporting or rendering. + * This is a last resort! If this branch is running as part of regular usage + * it can be considered a bug. */ + const float(*oldkey)[3] = static_cast<const float(*)[3]>(currkey->data); + copy_v3_v3(currkey_data[i], oldkey[keyi]); + } + else { + /* Fail! fill in with dummy value. */ + copy_v3_v3(currkey_data[i], eve->co); + } + } + + currkey->totelem = bm->totvert; + if (currkey->data) { + MEM_freeN(currkey->data); + } + currkey->data = currkey_data; + } + } + + if (ofs) { + MEM_freeN(ofs); + } +} + +/** \} */ + BLI_INLINE void bmesh_quick_edgedraw_flag(MEdge *med, BMEdge *e) { /* This is a cheap way to set the edge draw, its not precise and will @@ -604,23 +892,8 @@ void BM_mesh_bm_to_me(Main *bmain, BMesh *bm, Mesh *me, const struct BMeshToMesh const int cd_edge_crease_offset = CustomData_get_offset(&bm->edata, CD_CREASE); const int cd_shape_keyindex_offset = CustomData_get_offset(&bm->vdata, CD_SHAPE_KEYINDEX); - MVert *oldverts = nullptr; const int ototvert = me->totvert; - if (me->key && (cd_shape_keyindex_offset != -1)) { - /* Keep the old verts in case we are working on* a key, which is done at the end. */ - - /* Use the array in-place instead of duplicating the array. */ -#if 0 - oldverts = MEM_dupallocN(me->mvert); -#else - oldverts = me->mvert; - me->mvert = nullptr; - CustomData_update_typemap(&me->vdata); - CustomData_set_layer(&me->vdata, CD_MVERT, nullptr); -#endif - } - /* Free custom data. */ CustomData_free(&me->vdata, me->totvert); CustomData_free(&me->edata, me->totedge); @@ -846,152 +1119,8 @@ void BM_mesh_bm_to_me(Main *bmain, BMesh *bm, Mesh *me, const struct BMeshToMesh } } - /* See comment below, this logic is in twice. */ - if (me->key) { - KeyBlock *currkey; - KeyBlock *actkey = static_cast<KeyBlock *>(BLI_findlink(&me->key->block, bm->shapenr - 1)); - - float(*ofs)[3] = nullptr; - - /* Go through and find any shape-key custom-data layers - * that might not have corresponding KeyBlocks, and add them if necessary. */ - for (i = 0; i < bm->vdata.totlayer; i++) { - if (bm->vdata.layers[i].type != CD_SHAPEKEY) { - continue; - } - - for (currkey = (KeyBlock *)me->key->block.first; currkey; currkey = currkey->next) { - if (currkey->uid == bm->vdata.layers[i].uid) { - break; - } - } - - if (!currkey) { - currkey = BKE_keyblock_add(me->key, bm->vdata.layers[i].name); - currkey->uid = bm->vdata.layers[i].uid; - } - } - - /* Editing the base key should update others. */ - if (/* Only need offsets for relative shape keys. */ - (me->key->type == KEY_RELATIVE) && - - /* Unlikely, but the active key may not be valid if the - * BMesh and the mesh are out of sync. */ - (actkey != nullptr) && - - /* Not used here, but 'oldverts' is used later for applying 'ofs'. */ - (oldverts != nullptr) && - - /* Needed for referencing oldverts. */ - (cd_shape_keyindex_offset != -1)) { - - const bool act_is_basis = BKE_keyblock_is_basis(me->key, bm->shapenr - 1); - - /* Active key is a base. */ - if (act_is_basis) { - const float(*fp)[3] = static_cast<const float(*)[3]>(actkey->data); - - ofs = static_cast<float(*)[3]>( - MEM_callocN(sizeof(float[3]) * bm->totvert, "currkey->data")); - mvert = me->mvert; - BM_ITER_MESH_INDEX (eve, &iter, bm, BM_VERTS_OF_MESH, i) { - const int keyi = BM_ELEM_CD_GET_INT(eve, cd_shape_keyindex_offset); - - /* Could use 'eve->co' or 'mvert->co', they're the same at this point. */ - if (keyi != ORIGINDEX_NONE && keyi < actkey->totelem) { - sub_v3_v3v3(ofs[i], mvert->co, fp[keyi]); - } - else { - /* If there are new vertices in the mesh, we can't propagate the offset - * because it will only work for the existing vertices and not the new - * ones, creating a mess when doing e.g. subdivide + translate. */ - MEM_freeN(ofs); - ofs = nullptr; - break; - } - - mvert++; - } - } - } - - LISTBASE_FOREACH (KeyBlock *, currkey, &me->key->block) { - int keyi; - const float(*ofs_pt)[3] = ofs; - float *newkey, (*oldkey)[3], *fp; - - const int currkey_uuid = bm_to_mesh_shape_layer_index_from_kb(bm, currkey); - const int cd_shape_offset = (currkey_uuid == -1) ? -1 : - CustomData_get_n_offset(&bm->vdata, - CD_SHAPEKEY, - currkey_uuid); - const bool apply_offset = (cd_shape_offset != -1) && (ofs != nullptr) && - (currkey != actkey) && (bm->shapenr - 1 == currkey->relative); - - fp = newkey = static_cast<float *>( - MEM_callocN(me->key->elemsize * bm->totvert, "currkey->data")); - oldkey = static_cast<float(*)[3]>(currkey->data); - - mvert = me->mvert; - BM_ITER_MESH (eve, &iter, bm, BM_VERTS_OF_MESH) { - - if (currkey == actkey) { - copy_v3_v3(fp, eve->co); - - if (actkey != me->key->refkey) { /* Important see bug T30771. */ - if (cd_shape_keyindex_offset != -1) { - if (oldverts) { - keyi = BM_ELEM_CD_GET_INT(eve, cd_shape_keyindex_offset); - if (keyi != ORIGINDEX_NONE && keyi < currkey->totelem) { /* Valid old vertex. */ - copy_v3_v3(mvert->co, oldverts[keyi].co); - } - } - } - } - } - else if (cd_shape_offset != -1) { - /* In most cases this runs. */ - copy_v3_v3(fp, (const float *)BM_ELEM_CD_GET_VOID_P(eve, cd_shape_offset)); - } - else if ((oldkey != nullptr) && (cd_shape_keyindex_offset != -1) && - ((keyi = BM_ELEM_CD_GET_INT(eve, cd_shape_keyindex_offset)) != ORIGINDEX_NONE) && - (keyi < currkey->totelem)) { - /* Old method of reconstructing keys via vertices original key indices, - * currently used if the new method above fails - * (which is theoretically possible in certain cases of undo). */ - copy_v3_v3(fp, oldkey[keyi]); - } - else { - /* Fail! fill in with dummy value. */ - copy_v3_v3(fp, mvert->co); - } - - /* Propagate edited basis offsets to other shapes. */ - if (apply_offset) { - add_v3_v3(fp, *ofs_pt++); - /* Apply back new coordinates shape-keys that have offset into BMesh. - * Otherwise, in case we call again #BM_mesh_bm_to_me on same BMesh, - * we'll apply diff from previous call to #BM_mesh_bm_to_me, - * to shape-key values from *original creation of the BMesh*. See T50524. */ - copy_v3_v3((float *)BM_ELEM_CD_GET_VOID_P(eve, cd_shape_offset), fp); - } - - fp += 3; - mvert++; - } - - currkey->totelem = bm->totvert; - if (currkey->data) { - MEM_freeN(currkey->data); - } - currkey->data = newkey; - } - - if (ofs) { - MEM_freeN(ofs); - } + bm_to_mesh_shape(bm, me->key, me->mvert); } /* Run this even when shape keys aren't used since it may be used for hooks or vertex parents. */ @@ -1005,10 +1134,6 @@ void BM_mesh_bm_to_me(Main *bmain, BMesh *bm, Mesh *me, const struct BMeshToMesh } } - if (oldverts != nullptr) { - MEM_freeN(oldverts); - } - /* Topology could be changed, ensure #CD_MDISPS are ok. */ multires_topology_changed(me); |