orcaslicer/src/slic3r/GUI/MeshUtils.cpp

313 lines
11 KiB
C++

#include "MeshUtils.hpp"
#include "libslic3r/Tesselate.hpp"
#include "libslic3r/TriangleMesh.hpp"
#include "libslic3r/TriangleMeshSlicer.hpp"
#include "libslic3r/ClipperUtils.hpp"
#include "libslic3r/Model.hpp"
#include "slic3r/GUI/Camera.hpp"
#include <GL/glew.h>
#include <igl/unproject.h>
namespace Slic3r {
namespace GUI {
void MeshClipper::set_plane(const ClippingPlane& plane)
{
if (m_plane != plane) {
m_plane = plane;
m_triangles_valid = false;
}
}
void MeshClipper::set_limiting_plane(const ClippingPlane& plane)
{
if (m_limiting_plane != plane) {
m_limiting_plane = plane;
m_triangles_valid = false;
}
}
void MeshClipper::set_mesh(const TriangleMesh& mesh)
{
if (m_mesh != &mesh) {
m_mesh = &mesh;
m_triangles_valid = false;
m_triangles2d.resize(0);
}
}
void MeshClipper::set_negative_mesh(const TriangleMesh& mesh)
{
if (m_negative_mesh != &mesh) {
m_negative_mesh = &mesh;
m_triangles_valid = false;
m_triangles2d.resize(0);
}
}
void MeshClipper::set_transformation(const Geometry::Transformation& trafo)
{
if (! m_trafo.get_matrix().isApprox(trafo.get_matrix())) {
m_trafo = trafo;
m_triangles_valid = false;
m_triangles2d.resize(0);
}
}
void MeshClipper::render_cut()
{
if (! m_triangles_valid)
recalculate_triangles();
if (m_vertex_array.has_VBOs())
m_vertex_array.render();
}
void MeshClipper::recalculate_triangles()
{
const Transform3f& instance_matrix_no_translation_no_scaling = m_trafo.get_matrix(true,false,true).cast<float>();
const Vec3f& scaling = m_trafo.get_scaling_factor().cast<float>();
// Calculate clipping plane normal in mesh coordinates.
Vec3f up_noscale = instance_matrix_no_translation_no_scaling.inverse() * m_plane.get_normal().cast<float>();
Vec3d up (up_noscale(0)*scaling(0), up_noscale(1)*scaling(1), up_noscale(2)*scaling(2));
// Calculate distance from mesh origin to the clipping plane (in mesh coordinates).
float height_mesh = m_plane.distance(m_trafo.get_offset()) * (up_noscale.norm()/up.norm());
// Now do the cutting
MeshSlicingParams slicing_params;
slicing_params.trafo.rotate(Eigen::Quaternion<double, Eigen::DontAlign>::FromTwoVectors(up, Vec3d::UnitZ()));
ExPolygons expolys = union_ex(slice_mesh(m_mesh->its, height_mesh, slicing_params));
if (m_negative_mesh && !m_negative_mesh->empty()) {
ExPolygons neg_expolys = union_ex(slice_mesh(m_negative_mesh->its, height_mesh, slicing_params));
expolys = diff_ex(expolys, neg_expolys);
}
// Triangulate and rotate the cut into world coords:
Eigen::Quaterniond q;
q.setFromTwoVectors(Vec3d::UnitZ(), up);
Transform3d tr = Transform3d::Identity();
tr.rotate(q);
tr = m_trafo.get_matrix() * tr;
if (m_limiting_plane != ClippingPlane::ClipsNothing())
{
// Now remove whatever ended up below the limiting plane (e.g. sinking objects).
// First transform the limiting plane from world to mesh coords.
// Note that inverse of tr transforms the plane from world to horizontal.
Vec3d normal_old = m_limiting_plane.get_normal().normalized();
Vec3d normal_new = (tr.matrix().block<3,3>(0,0).transpose() * normal_old).normalized();
// normal_new should now be the plane normal in mesh coords. To find the offset,
// transform a point and set offset so it belongs to the transformed plane.
Vec3d pt = Vec3d::Zero();
double plane_offset = m_limiting_plane.get_data()[3];
if (std::abs(normal_old.z()) > 0.5) // normal is normalized, at least one of the coords if larger than sqrt(3)/3 = 0.57
pt.z() = - plane_offset / normal_old.z();
else if (std::abs(normal_old.y()) > 0.5)
pt.y() = - plane_offset / normal_old.y();
else
pt.x() = - plane_offset / normal_old.x();
pt = tr.inverse() * pt;
double offset = -(normal_new.dot(pt));
if (std::abs(normal_old.dot(m_plane.get_normal().normalized())) > 0.99) {
// The cuts are parallel, show all or nothing.
if (offset < height_mesh)
expolys.clear();
} else {
// The cut is a horizontal plane defined by z=height_mesh.
// ax+by+e=0 is the line of intersection with the limiting plane.
// Normalized so a^2 + b^2 = 1.
double len = std::hypot(normal_new.x(), normal_new.y());
if (len == 0.)
return;
double a = normal_new.x() / len;
double b = normal_new.y() / len;
double e = (normal_new.z() * height_mesh + offset) / len;
if (b == 0.)
return;
// We need a half-plane to limit the cut. Get angle of the intersecting line.
double angle = std::atan(-a/b);
if (b > 0) // select correct half-plane
angle += M_PI;
// We'll take a big rectangle above x-axis and rotate and translate
// it so it lies on our line. This will be the figure to subtract
// from the cut. The coordinates must not overflow after the transform,
// make the rectangle a bit smaller.
coord_t size = (std::numeric_limits<coord_t>::max() - scale_(std::max(std::abs(e*a), std::abs(e*b)))) / 4;
Polygons ep {Polygon({Point(-size, 0), Point(size, 0), Point(size, 2*size), Point(-size, 2*size)})};
ep.front().rotate(angle);
ep.front().translate(scale_(-e * a), scale_(-e * b));
expolys = diff_ex(expolys, ep);
}
}
m_triangles2d = triangulate_expolygons_2f(expolys, m_trafo.get_matrix().matrix().determinant() < 0.);
tr.pretranslate(0.001 * m_plane.get_normal().normalized()); // to avoid z-fighting
m_vertex_array.release_geometry();
for (auto it=m_triangles2d.cbegin(); it != m_triangles2d.cend(); it=it+3) {
m_vertex_array.push_geometry(tr * Vec3d((*(it+0))(0), (*(it+0))(1), height_mesh), up);
m_vertex_array.push_geometry(tr * Vec3d((*(it+1))(0), (*(it+1))(1), height_mesh), up);
m_vertex_array.push_geometry(tr * Vec3d((*(it+2))(0), (*(it+2))(1), height_mesh), up);
size_t idx = it - m_triangles2d.cbegin();
m_vertex_array.push_triangle(idx, idx+1, idx+2);
}
m_vertex_array.finalize_geometry(true);
m_triangles_valid = true;
}
Vec3f MeshRaycaster::get_triangle_normal(size_t facet_idx) const
{
return m_normals[facet_idx];
}
void MeshRaycaster::line_from_mouse_pos(const Vec2d& mouse_pos, const Transform3d& trafo, const Camera& camera,
Vec3d& point, Vec3d& direction) const
{
Matrix4d modelview = camera.get_view_matrix().matrix();
Matrix4d projection= camera.get_projection_matrix().matrix();
Vec4i viewport(camera.get_viewport().data());
Vec3d pt1;
Vec3d pt2;
igl::unproject(Vec3d(mouse_pos(0), viewport[3] - mouse_pos(1), 0.),
modelview, projection, viewport, pt1);
igl::unproject(Vec3d(mouse_pos(0), viewport[3] - mouse_pos(1), 1.),
modelview, projection, viewport, pt2);
Transform3d inv = trafo.inverse();
pt1 = inv * pt1;
pt2 = inv * pt2;
point = pt1;
direction = pt2-pt1;
}
bool MeshRaycaster::unproject_on_mesh(const Vec2d& mouse_pos, const Transform3d& trafo, const Camera& camera,
Vec3f& position, Vec3f& normal, const ClippingPlane* clipping_plane,
size_t* facet_idx) const
{
Vec3d point;
Vec3d direction;
line_from_mouse_pos(mouse_pos, trafo, camera, point, direction);
std::vector<sla::IndexedMesh::hit_result> hits = m_emesh.query_ray_hits(point, direction);
if (hits.empty())
return false; // no intersection found
unsigned i = 0;
// Remove points that are obscured or cut by the clipping plane.
// Also, remove anything below the bed (sinking objects).
for (i=0; i<hits.size(); ++i) {
Vec3d transformed_hit = trafo * hits[i].position();
if (transformed_hit.z() >= SINKING_Z_THRESHOLD &&
(! clipping_plane || ! clipping_plane->is_point_clipped(transformed_hit)))
break;
}
if (i==hits.size() || (hits.size()-i) % 2 != 0) {
// All hits are either clipped, or there is an odd number of unclipped
// hits - meaning the nearest must be from inside the mesh.
return false;
}
// Now stuff the points in the provided vector and calculate normals if asked about them:
position = hits[i].position().cast<float>();
normal = hits[i].normal().cast<float>();
if (facet_idx)
*facet_idx = hits[i].face();
return true;
}
std::vector<unsigned> MeshRaycaster::get_unobscured_idxs(const Geometry::Transformation& trafo, const Camera& camera, const std::vector<Vec3f>& points,
const ClippingPlane* clipping_plane) const
{
std::vector<unsigned> out;
const Transform3d& instance_matrix_no_translation_no_scaling = trafo.get_matrix(true,false,true);
Vec3d direction_to_camera = -camera.get_dir_forward();
Vec3d direction_to_camera_mesh = (instance_matrix_no_translation_no_scaling.inverse() * direction_to_camera).normalized().eval();
direction_to_camera_mesh = direction_to_camera_mesh.cwiseProduct(trafo.get_scaling_factor());
const Transform3d inverse_trafo = trafo.get_matrix().inverse();
for (size_t i=0; i<points.size(); ++i) {
const Vec3f& pt = points[i];
if (clipping_plane && clipping_plane->is_point_clipped(pt.cast<double>()))
continue;
bool is_obscured = false;
// Cast a ray in the direction of the camera and look for intersection with the mesh:
std::vector<sla::IndexedMesh::hit_result> hits;
// Offset the start of the ray by EPSILON to account for numerical inaccuracies.
hits = m_emesh.query_ray_hits((inverse_trafo * pt.cast<double>() + direction_to_camera_mesh * EPSILON),
direction_to_camera_mesh);
if (! hits.empty()) {
// If the closest hit facet normal points in the same direction as the ray,
// we are looking through the mesh and should therefore discard the point:
if (hits.front().normal().dot(direction_to_camera_mesh.cast<double>()) > 0)
is_obscured = true;
// Eradicate all hits that the caller wants to ignore
for (unsigned j=0; j<hits.size(); ++j) {
if (clipping_plane && clipping_plane->is_point_clipped(trafo.get_matrix() * hits[j].position())) {
hits.erase(hits.begin()+j);
--j;
}
}
// FIXME: the intersection could in theory be behind the camera, but as of now we only have camera direction.
// Also, the threshold is in mesh coordinates, not in actual dimensions.
if (! hits.empty())
is_obscured = true;
}
if (! is_obscured)
out.push_back(i);
}
return out;
}
Vec3f MeshRaycaster::get_closest_point(const Vec3f& point, Vec3f* normal) const
{
int idx = 0;
Vec3d closest_point;
m_emesh.squared_distance(point.cast<double>(), idx, closest_point);
if (normal)
*normal = m_normals[idx];
return closest_point.cast<float>();
}
} // namespace GUI
} // namespace Slic3r