DYT/Tool/OpenSceneGraph-3.6.5/include/draco/mesh/triangle_soup_mesh_builder.h
2024-12-25 07:49:36 +08:00

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5.2 KiB
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// Copyright 2016 The Draco Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#ifndef DRACO_MESH_TRIANGLE_SOUP_MESH_BUILDER_H_
#define DRACO_MESH_TRIANGLE_SOUP_MESH_BUILDER_H_
#include <utility>
#include <vector>
#include "draco/draco_features.h"
#ifdef DRACO_TRANSCODER_SUPPORTED
#include "draco/core/status.h"
#endif
#include "draco/mesh/mesh.h"
namespace draco {
// Class for building meshes directly from attribute values that can be
// specified for each face corner. All attributes are automatically
// deduplicated.
class TriangleSoupMeshBuilder {
public:
// Index type of the inserted element.
typedef FaceIndex ElementIndex;
// Starts mesh building for a given number of faces.
// TODO(ostava): Currently it's necessary to select the correct number of
// faces upfront. This should be generalized, but it will require us to
// rewrite our attribute resizing functions.
void Start(int num_faces);
#ifdef DRACO_TRANSCODER_SUPPORTED
// Sets mesh name.
void SetName(const std::string &name);
#endif // DRACO_TRANSCODER_SUPPORTED
// Adds an empty attribute to the mesh. Returns the new attribute's id.
int AddAttribute(GeometryAttribute::Type attribute_type,
int8_t num_components, DataType data_type);
int AddAttribute(GeometryAttribute::Type attribute_type,
int8_t num_components, DataType data_type, bool normalized);
// Sets values for a given attribute on all corners of a given face.
void SetAttributeValuesForFace(int att_id, FaceIndex face_id,
const void *corner_value_0,
const void *corner_value_1,
const void *corner_value_2);
#ifdef DRACO_TRANSCODER_SUPPORTED
// Converts input values of type T into internal representation used by
// |att_id|. Each input value needs to have |input_num_components| entries.
template <typename T>
Status ConvertAndSetAttributeValuesForFace(int att_id, FaceIndex face_id,
int input_num_components,
const T *corner_value_0,
const T *corner_value_1,
const T *corner_value_2);
#endif
// Sets value for a per-face attribute. If all faces of a given attribute are
// set with this method, the attribute will be marked as per-face, otherwise
// it will be marked as per-corner attribute.
void SetPerFaceAttributeValueForFace(int att_id, FaceIndex face_id,
const void *value);
// Add metadata.
void AddMetadata(std::unique_ptr<GeometryMetadata> metadata) {
mesh_->AddMetadata(std::move(metadata));
}
// Sets the unique ID for an attribute created with AddAttribute().
void SetAttributeUniqueId(int att_id, uint32_t unique_id);
#ifdef DRACO_TRANSCODER_SUPPORTED
// Sets attribute name.
void SetAttributeName(int att_id, const std::string &name);
#endif // DRACO_TRANSCODER_SUPPORTED
// Add metadata for an attribute.
void AddAttributeMetadata(int32_t att_id,
std::unique_ptr<AttributeMetadata> metadata) {
mesh_->AddAttributeMetadata(att_id, std::move(metadata));
}
// Finalizes the mesh or returns nullptr on error.
// Once this function is called, the builder becomes invalid and cannot be
// used until the method Start() is called again.
std::unique_ptr<Mesh> Finalize();
private:
std::vector<int8_t> attribute_element_types_;
std::unique_ptr<Mesh> mesh_;
};
#ifdef DRACO_TRANSCODER_SUPPORTED
template <typename T>
Status TriangleSoupMeshBuilder::ConvertAndSetAttributeValuesForFace(
int att_id, FaceIndex face_id, int input_num_components,
const T *corner_value_0, const T *corner_value_1, const T *corner_value_2) {
const int start_index = 3 * face_id.value();
PointAttribute *const att = mesh_->attribute(att_id);
DRACO_RETURN_IF_ERROR(
att->ConvertAndSetAttributeValue(AttributeValueIndex(start_index + 0),
input_num_components, corner_value_0));
DRACO_RETURN_IF_ERROR(
att->ConvertAndSetAttributeValue(AttributeValueIndex(start_index + 1),
input_num_components, corner_value_1));
DRACO_RETURN_IF_ERROR(
att->ConvertAndSetAttributeValue(AttributeValueIndex(start_index + 2),
input_num_components, corner_value_2));
mesh_->SetFace(face_id,
{{PointIndex(start_index), PointIndex(start_index + 1),
PointIndex(start_index + 2)}});
attribute_element_types_[att_id] = MESH_CORNER_ATTRIBUTE;
return OkStatus();
}
#endif // DRACO_TRANSCODER_SUPPORTED
} // namespace draco
#endif // DRACO_MESH_TRIANGLE_SOUP_MESH_BUILDER_H_