mesh_split.cpp

#include <iostream>
#include "m_mesh_split.h"
#include "stopwatch.h"

// use PaintUniformColor instead
void PaintMesh(open3d::geometry::TriangleMesh& mesh,
	const Eigen::Vector3d& color) {
	mesh.vertex_colors_.resize(mesh.vertices_.size());
#pragma omp parallel for schedule(static)
	for (auto i = 0; i < mesh.vertices_.size(); i++) {
		mesh.vertex_colors_[i] = color;
	}
}

int main(int argc, char* argv[]) {
	assert(argc == 2);  // argv[1]: mesh_file

	std::shared_ptr<open3d::geometry::TriangleMesh> mesh;
	{
		TIME_BLOCK("- load mesh: ");
		mesh = open3d::io::CreateMeshFromFile(argv[1], false);
	}

	// by crop
	auto origin_bounding_box = mesh->GetAxisAlignedBoundingBox();
	auto diff = origin_bounding_box.GetMaxBound() - origin_bounding_box.GetMinBound();
	auto new_low_bound = Eigen::Vector3d(origin_bounding_box.GetMinBound().x(), origin_bounding_box.GetMinBound().y(), origin_bounding_box.GetMinBound().z() + diff.z() / 2);
	auto crop_bounding_box = open3d::geometry::AxisAlignedBoundingBox(new_low_bound, origin_bounding_box.GetMaxBound());

	std::shared_ptr<open3d::geometry::TriangleMesh> mesh_1, mesh_2;
	{
		TIME_BLOCK("- mesh crop inside: ");
		mesh_1 = M_MATH::MeshCrop(*mesh, crop_bounding_box, false);
	}
	{
		TIME_BLOCK("- mesh crop outside: ");
		mesh_2 = M_MATH::MeshCrop(*mesh, crop_bounding_box);
	}

	//PaintMesh(*mesh_1, Eigen::Vector3d(0.0, 1.0, 0.0));
	//PaintMesh(*mesh_2, Eigen::Vector3d(1.0, 0.0, 0.0));
	mesh_1->PaintUniformColor(Eigen::Vector3d(0.0, 1.0, 0.0));
	mesh_2->PaintUniformColor(Eigen::Vector3d(1.0, 0.0, 0.0));
	open3d::visualization::DrawGeometries({ mesh_1, mesh_2 }, "cropped mesh", 1920, 1080);
	

	/*
	// by HM
	open3d::geometry::TriangleMesh l_mesh, r_mesh;
	auto diff = mesh->GetMaxBound() - mesh->GetMinBound();
	auto plane_center = Eigen::Vector3d(diff.x() / 2, diff.y() / 2, diff.z() / 2);
	auto plane_normal = Eigen::Vector3d(1, 1, 1);
	plane_normal.normalize();
	M_MATH::MeshCut(*mesh, plane_center, plane_normal, l_mesh, r_mesh);
	PaintMesh(l_mesh, Eigen::Vector3d(0.0, 1.0, 0.0));
	PaintMesh(r_mesh, Eigen::Vector3d(1.0, 0.0, 0.0));
	std::shared_ptr<open3d::geometry::TriangleMesh> p_l_mesh, p_r_mesh;
	p_l_mesh.reset(&l_mesh);
	p_r_mesh.reset(&r_mesh);
	printf("left mesh vertices size: %llu, triangles size: %llu\n", p_l_mesh->vertices_.size(), p_l_mesh->triangles_.size());
	printf("right mesh vertices size: %llu, triangles size: %llu\n", p_r_mesh->vertices_.size(), p_r_mesh->triangles_.size());
	open3d::visualization::DrawGeometries({ p_l_mesh, p_r_mesh }, "mesh", 1920, 1080);
	open3d::visualization::DrawGeometries({ p_l_mesh }, "left mesh", 1920, 1080);
	open3d::visualization::DrawGeometries({ p_r_mesh }, "right mesh", 1920, 1080);
	*/

	return 0;
}