This repository has been archived on 2023-10-09. You can view files and clone it. You cannot open issues or pull requests or push a commit.
Files
blender-archive/source/blender/io/alembic/intern/abc_reader_points.cc
Sybren A. Stüvel bab2260b59 Fix T71981: Alembic vertex interpolation can jumble mesh
Add an option to disable Alembic vertex interpolation.
Bump subversion from 5 to 6.

Alembic stores mesh samples at specific time keys; when a frame in
Blender maps to a timecode between two samples, Blender will interpolate
the mesh vertex positions. This interpolation only happens when the mesh
has a constant topology, but sometimes this was not detected properly
when the vertices change order, but the number of mesh elements remains
the same. This would result in a mesh with jumbled up vertices (T71981).
With this patch, users have the ability to disable vertex interpolation.

An alternative would be to have better detection of topology changes,
but that that'll cause a considerable slowdown.

Maniphest Tasks: T71981

Differential Revision: https://developer.blender.org/D9041
2020-09-29 16:10:16 +02:00

163 lines
4.9 KiB
C++

/*
* 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) 2016 Kévin Dietrich.
* All rights reserved.
*/
/** \file
* \ingroup balembic
*/
#include "abc_reader_points.h"
#include "abc_reader_mesh.h"
#include "abc_reader_transform.h"
#include "abc_util.h"
#include "DNA_mesh_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"
#include "BKE_customdata.h"
#include "BKE_mesh.h"
#include "BKE_object.h"
using Alembic::AbcGeom::kWrapExisting;
using Alembic::AbcGeom::N3fArraySamplePtr;
using Alembic::AbcGeom::P3fArraySamplePtr;
using Alembic::AbcGeom::ICompoundProperty;
using Alembic::AbcGeom::IN3fArrayProperty;
using Alembic::AbcGeom::IPoints;
using Alembic::AbcGeom::IPointsSchema;
using Alembic::AbcGeom::ISampleSelector;
namespace blender::io::alembic {
AbcPointsReader::AbcPointsReader(const Alembic::Abc::IObject &object, ImportSettings &settings)
: AbcObjectReader(object, settings)
{
IPoints ipoints(m_iobject, kWrapExisting);
m_schema = ipoints.getSchema();
get_min_max_time(m_iobject, m_schema, m_min_time, m_max_time);
}
bool AbcPointsReader::valid() const
{
return m_schema.valid();
}
bool AbcPointsReader::accepts_object_type(
const Alembic::AbcCoreAbstract::ObjectHeader &alembic_header,
const Object *const ob,
const char **err_str) const
{
if (!Alembic::AbcGeom::IPoints::matches(alembic_header)) {
*err_str =
"Object type mismatch, Alembic object path pointed to Points when importing, but not any "
"more.";
return false;
}
if (ob->type != OB_MESH) {
*err_str = "Object type mismatch, Alembic object path points to Points.";
return false;
}
return true;
}
void AbcPointsReader::readObjectData(Main *bmain, const Alembic::Abc::ISampleSelector &sample_sel)
{
Mesh *mesh = BKE_mesh_add(bmain, m_data_name.c_str());
Mesh *read_mesh = this->read_mesh(mesh, sample_sel, 0, NULL);
if (read_mesh != mesh) {
BKE_mesh_nomain_to_mesh(read_mesh, mesh, m_object, &CD_MASK_MESH, true);
}
if (m_settings->validate_meshes) {
BKE_mesh_validate(mesh, false, false);
}
m_object = BKE_object_add_only_object(bmain, OB_MESH, m_object_name.c_str());
m_object->data = mesh;
if (has_animations(m_schema, m_settings)) {
addCacheModifier();
}
}
void read_points_sample(const IPointsSchema &schema,
const ISampleSelector &selector,
CDStreamConfig &config)
{
Alembic::AbcGeom::IPointsSchema::Sample sample = schema.getValue(selector);
const P3fArraySamplePtr &positions = sample.getPositions();
ICompoundProperty prop = schema.getArbGeomParams();
N3fArraySamplePtr vnormals;
if (has_property(prop, "N")) {
const Alembic::Util::uint32_t itime = static_cast<Alembic::Util::uint32_t>(
selector.getRequestedTime());
const IN3fArrayProperty &normals_prop = IN3fArrayProperty(prop, "N", itime);
if (normals_prop) {
vnormals = normals_prop.getValue(selector);
}
}
read_mverts(config.mvert, positions, vnormals);
}
struct Mesh *AbcPointsReader::read_mesh(struct Mesh *existing_mesh,
const ISampleSelector &sample_sel,
int read_flag,
const char **err_str)
{
IPointsSchema::Sample sample;
try {
sample = m_schema.getValue(sample_sel);
}
catch (Alembic::Util::Exception &ex) {
*err_str = "Error reading points sample; more detail on the console";
printf("Alembic: error reading points sample for '%s/%s' at time %f: %s\n",
m_iobject.getFullName().c_str(),
m_schema.getName().c_str(),
sample_sel.getRequestedTime(),
ex.what());
return existing_mesh;
}
const P3fArraySamplePtr &positions = sample.getPositions();
Mesh *new_mesh = NULL;
if (existing_mesh->totvert != positions->size()) {
new_mesh = BKE_mesh_new_nomain(positions->size(), 0, 0, 0, 0);
}
Mesh *mesh_to_export = new_mesh ? new_mesh : existing_mesh;
const bool use_vertex_interpolation = read_flag & MOD_MESHSEQ_INTERPOLATE_VERTICES;
CDStreamConfig config = get_config(mesh_to_export, use_vertex_interpolation);
read_points_sample(m_schema, sample_sel, config);
return mesh_to_export;
}
} // namespace blender::io::alembic