http://cg.iit.bme.hu/portal/node/312 https://portal.vik.bme.hu/kepzes/targyak/VIIIMA25
Dr. Várady Tamás, Dr. Salvi Péter BME, Villamosmérnöki és Informatikai Kar Irányítástechnika és Informatika Tanszék
Window::open()
auto filename = QFileDialog::getOpenFileName(this, tr("Open File"), last_directory, tr("Readable files (*.obj *.ply *.stl *.bzr);;" "Mesh (*.obj *.ply *.stl);;" "Bézier surface (*.bzr);;" "All files (*.*)"));
Viewer
#include "bezier.hh" bool Viewer::open(std::string filename) { std::shared_ptr<Object> surface; if (filename.ends_with(".bzr")) surface = std::make_shared<Bezier>(filename); else surface = std::make_shared<Mesh>(filename); // ... }
C
show_solid
struct Visualization { bool show_control_points; // ... }; Visualization::Visualization() : type(VisType::PLAIN), show_control_points(true), show_solid(true), show_wireframe(false), mean_min(0.0), mean_max(0.0), cutoff_ratio(0.05) { }
#pragma once #include "object.hh" class Bezier : public Object { public: Bezier(std::string filename); virtual ~Bezier(); virtual void draw(const Visualization &vis) const override; virtual void drawWithNames(const Visualization &vis) const override; virtual Vector postSelection(int selected) override; virtual void movement(int selected, const Vector &pos) override; virtual void updateBaseMesh() override; virtual bool reload() override; private: size_t degree[2]; std::vector<Vector> control_points; };
#include "bezier.hh" Bezier::Bezier(std::string filename) : Object(filename) { reload(); }
.bzr
n m P00x P00y P00z ... P0mx P0my P0mz P10x P10y P10z ... Pnmx Pnmy Pnmz
#include <fstream> bool Bezier::reload() { size_t n, m; try { std::ifstream f(filename); f.exceptions(std::ios::failbit | std::ios::badbit); f >> n >> m; degree[0] = n++; degree[1] = m++; control_points.resize(n * m); for (size_t i = 0, index = 0; i < n; ++i) for (size_t j = 0; j < m; ++j, ++index) f >> control_points[index][0] >> control_points[index][1] >> control_points[index][2]; } catch(std::ifstream::failure &) { return false; } updateBaseMesh(); return true; }
void Bezier::draw(const Visualization &vis) const { Object::draw(vis); if (vis.show_control_points) { glDisable(GL_LIGHTING); glLineWidth(3.0); glColor3d(0.3, 0.3, 1.0); size_t m = degree[1] + 1; for (size_t k = 0; k < 2; ++k) for (size_t i = 0; i <= degree[k]; ++i) { glBegin(GL_LINE_STRIP); for (size_t j = 0; j <= degree[1-k]; ++j) { size_t const index = k ? j * m + i : i * m + j; const auto &p = control_points[index]; glVertex3dv(p.data()); } glEnd(); } glLineWidth(1.0); glPointSize(8.0); glColor3d(1.0, 0.0, 1.0); glBegin(GL_POINTS); for (const auto &p : control_points) glVertex3dv(p.data()); glEnd(); glPointSize(1.0); glEnable(GL_LIGHTING); } }
void Bezier::updateBaseMesh() { size_t resolution = 50; mesh.clear(); std::vector<BaseMesh::VertexHandle> handles, tri; size_t n = degree[0], m = degree[1]; std::vector<double> coeff_u, coeff_v; for (size_t i = 0; i < resolution; ++i) { double u = (double)i / (double)(resolution - 1); bernstein(n, u, coeff_u); for (size_t j = 0; j < resolution; ++j) { double v = (double)j / (double)(resolution - 1); bernstein(m, v, coeff_v); Vector p(0.0, 0.0, 0.0); for (size_t k = 0, index = 0; k <= n; ++k) for (size_t l = 0; l <= m; ++l, ++index) p += control_points[index] * coeff_u[k] * coeff_v[l]; handles.push_back(mesh.add_vertex(p)); } } // ... lapok készítése ... Object::updateBaseMesh(); }
void Bezier::updateBaseMesh() { size_t resolution = 50; mesh.clear(); std::vector<BaseMesh::VertexHandle> handles, tri; // ... csúcsok kiértékelése ... for (size_t i = 0; i < resolution - 1; ++i) for (size_t j = 0; j < resolution - 1; ++j) { tri.clear(); tri.push_back(handles[i * resolution + j]); tri.push_back(handles[i * resolution + j + 1]); tri.push_back(handles[(i + 1) * resolution + j]); mesh.add_face(tri); tri.clear(); tri.push_back(handles[(i + 1) * resolution + j]); tri.push_back(handles[i * resolution + j + 1]); tri.push_back(handles[(i + 1) * resolution + j + 1]); mesh.add_face(tri); } Object::updateBaseMesh(); }
void Bezier::drawWithNames(const Visualization &vis) const { if (!vis.show_control_points) return; for (size_t i = 0; i < control_points.size(); ++i) { const auto &p = control_points[i]; glPushName(i); glRasterPos3dv(p.data()); glPopName(); } } Vector Bezier::postSelection(int selected) { return control_points[selected]; } void Bezier::movement(int selected, const Vector &pos) { control_points[selected] = pos; }