diff options
Diffstat (limited to 'source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc')
| -rw-r--r-- | source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc new file mode 100644 index 00000000000..63b52a4ad9a --- /dev/null +++ b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc @@ -0,0 +1,236 @@ +/* + * 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) 2021 by Blender Foundation. + * All rights reserved. + */ + +/** \file + * \ingroup draw + */ + +#include "MEM_guardedalloc.h" + +#include "BKE_mesh.h" + +#include "draw_cache_extract_mesh_private.h" + +namespace blender::draw { + +/* ---------------------------------------------------------------------- */ +/** \name Extract Edit UV angle stretch + * \{ */ + +typedef struct UVStretchAngle { + int16_t angle; + int16_t uv_angles[2]; +} UVStretchAngle; + +typedef struct MeshExtract_StretchAngle_Data { + UVStretchAngle *vbo_data; + MLoopUV *luv; + float auv[2][2], last_auv[2]; + float av[2][3], last_av[3]; + int cd_ofs; +} MeshExtract_StretchAngle_Data; + +static void compute_normalize_edge_vectors(float auv[2][2], + float av[2][3], + const float uv[2], + const float uv_prev[2], + const float co[3], + const float co_prev[3]) +{ + /* Move previous edge. */ + copy_v2_v2(auv[0], auv[1]); + copy_v3_v3(av[0], av[1]); + /* 2d edge */ + sub_v2_v2v2(auv[1], uv_prev, uv); + normalize_v2(auv[1]); + /* 3d edge */ + sub_v3_v3v3(av[1], co_prev, co); + normalize_v3(av[1]); +} + +static short v2_to_short_angle(const float v[2]) +{ + return atan2f(v[1], v[0]) * (float)M_1_PI * SHRT_MAX; +} + +static void edituv_get_edituv_stretch_angle(float auv[2][2], + const float av[2][3], + UVStretchAngle *r_stretch) +{ + /* Send UV's to the shader and let it compute the aspect corrected angle. */ + r_stretch->uv_angles[0] = v2_to_short_angle(auv[0]); + r_stretch->uv_angles[1] = v2_to_short_angle(auv[1]); + /* Compute 3D angle here. */ + r_stretch->angle = angle_normalized_v3v3(av[0], av[1]) * (float)M_1_PI * SHRT_MAX; + +#if 0 /* here for reference, this is done in shader now. */ + float uvang = angle_normalized_v2v2(auv0, auv1); + float ang = angle_normalized_v3v3(av0, av1); + float stretch = fabsf(uvang - ang) / (float)M_PI; + return 1.0f - pow2f(1.0f - stretch); +#endif +} + +static void extract_edituv_stretch_angle_init(const MeshRenderData *mr, + struct MeshBatchCache *UNUSED(cache), + void *buf, + void *tls_data) +{ + GPUVertBuf *vbo = static_cast<GPUVertBuf *>(buf); + static GPUVertFormat format = {0}; + if (format.attr_len == 0) { + /* Waning: adjust #UVStretchAngle struct accordingly. */ + GPU_vertformat_attr_add(&format, "angle", GPU_COMP_I16, 1, GPU_FETCH_INT_TO_FLOAT_UNIT); + GPU_vertformat_attr_add(&format, "uv_angles", GPU_COMP_I16, 2, GPU_FETCH_INT_TO_FLOAT_UNIT); + } + + GPU_vertbuf_init_with_format(vbo, &format); + GPU_vertbuf_data_alloc(vbo, mr->loop_len); + + MeshExtract_StretchAngle_Data *data = static_cast<MeshExtract_StretchAngle_Data *>(tls_data); + data->vbo_data = (UVStretchAngle *)GPU_vertbuf_get_data(vbo); + + /* Special iterator needed to save about half of the computing cost. */ + if (mr->extract_type == MR_EXTRACT_BMESH) { + data->cd_ofs = CustomData_get_offset(&mr->bm->ldata, CD_MLOOPUV); + } + else { + BLI_assert(ELEM(mr->extract_type, MR_EXTRACT_MAPPED, MR_EXTRACT_MESH)); + data->luv = (MLoopUV *)CustomData_get_layer(&mr->me->ldata, CD_MLOOPUV); + } +} + +static void extract_edituv_stretch_angle_iter_poly_bm(const MeshRenderData *mr, + const BMFace *f, + const int UNUSED(f_index), + void *_data) +{ + MeshExtract_StretchAngle_Data *data = static_cast<MeshExtract_StretchAngle_Data *>(_data); + float(*auv)[2] = data->auv, *last_auv = data->last_auv; + float(*av)[3] = data->av, *last_av = data->last_av; + BMLoop *l_iter, *l_first; + l_iter = l_first = BM_FACE_FIRST_LOOP(f); + do { + const int l_index = BM_elem_index_get(l_iter); + + const MLoopUV *luv, *luv_next; + BMLoop *l_next = l_iter->next; + if (l_iter == BM_FACE_FIRST_LOOP(f)) { + /* First loop in face. */ + BMLoop *l_tmp = l_iter->prev; + BMLoop *l_next_tmp = l_iter; + luv = (const MLoopUV *)BM_ELEM_CD_GET_VOID_P(l_tmp, data->cd_ofs); + luv_next = (const MLoopUV *)BM_ELEM_CD_GET_VOID_P(l_next_tmp, data->cd_ofs); + compute_normalize_edge_vectors(auv, + av, + luv->uv, + luv_next->uv, + bm_vert_co_get(mr, l_tmp->v), + bm_vert_co_get(mr, l_next_tmp->v)); + /* Save last edge. */ + copy_v2_v2(last_auv, auv[1]); + copy_v3_v3(last_av, av[1]); + } + if (l_next == BM_FACE_FIRST_LOOP(f)) { + /* Move previous edge. */ + copy_v2_v2(auv[0], auv[1]); + copy_v3_v3(av[0], av[1]); + /* Copy already calculated last edge. */ + copy_v2_v2(auv[1], last_auv); + copy_v3_v3(av[1], last_av); + } + else { + luv = (const MLoopUV *)BM_ELEM_CD_GET_VOID_P(l_iter, data->cd_ofs); + luv_next = (const MLoopUV *)BM_ELEM_CD_GET_VOID_P(l_next, data->cd_ofs); + compute_normalize_edge_vectors(auv, + av, + luv->uv, + luv_next->uv, + bm_vert_co_get(mr, l_iter->v), + bm_vert_co_get(mr, l_next->v)); + } + edituv_get_edituv_stretch_angle(auv, av, &data->vbo_data[l_index]); + } while ((l_iter = l_iter->next) != l_first); +} + +static void extract_edituv_stretch_angle_iter_poly_mesh(const MeshRenderData *mr, + const MPoly *mp, + const int UNUSED(mp_index), + void *_data) +{ + MeshExtract_StretchAngle_Data *data = static_cast<MeshExtract_StretchAngle_Data *>(_data); + + const int ml_index_end = mp->loopstart + mp->totloop; + for (int ml_index = mp->loopstart; ml_index < ml_index_end; ml_index += 1) { + float(*auv)[2] = data->auv, *last_auv = data->last_auv; + float(*av)[3] = data->av, *last_av = data->last_av; + int l_next = ml_index + 1; + const MVert *v, *v_next; + if (ml_index == mp->loopstart) { + /* First loop in face. */ + const int ml_index_last = ml_index_end - 1; + const int l_next_tmp = mp->loopstart; + v = &mr->mvert[mr->mloop[ml_index_last].v]; + v_next = &mr->mvert[mr->mloop[l_next_tmp].v]; + compute_normalize_edge_vectors( + auv, av, data->luv[ml_index_last].uv, data->luv[l_next_tmp].uv, v->co, v_next->co); + /* Save last edge. */ + copy_v2_v2(last_auv, auv[1]); + copy_v3_v3(last_av, av[1]); + } + if (l_next == ml_index_end) { + l_next = mp->loopstart; + /* Move previous edge. */ + copy_v2_v2(auv[0], auv[1]); + copy_v3_v3(av[0], av[1]); + /* Copy already calculated last edge. */ + copy_v2_v2(auv[1], last_auv); + copy_v3_v3(av[1], last_av); + } + else { + v = &mr->mvert[mr->mloop[ml_index].v]; + v_next = &mr->mvert[mr->mloop[l_next].v]; + compute_normalize_edge_vectors( + auv, av, data->luv[ml_index].uv, data->luv[l_next].uv, v->co, v_next->co); + } + edituv_get_edituv_stretch_angle(auv, av, &data->vbo_data[ml_index]); + } +} + +constexpr MeshExtract create_extractor_edituv_edituv_stretch_angle() +{ + MeshExtract extractor = {nullptr}; + extractor.init = extract_edituv_stretch_angle_init; + extractor.iter_poly_bm = extract_edituv_stretch_angle_iter_poly_bm; + extractor.iter_poly_mesh = extract_edituv_stretch_angle_iter_poly_mesh; + extractor.data_type = MR_DATA_NONE; + extractor.data_size = sizeof(MeshExtract_StretchAngle_Data); + extractor.use_threading = false; + extractor.mesh_buffer_offset = offsetof(MeshBufferCache, vbo.edituv_stretch_angle); + return extractor; +} + +/** \} */ + +} // namespace blender::draw + +extern "C" { +const MeshExtract extract_edituv_stretch_angle = + blender::draw::create_extractor_edituv_edituv_stretch_angle(); +} |