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Diffstat (limited to 'src/3rdparty/2geom/src/toys/find-derivative.cpp')
| -rw-r--r-- | src/3rdparty/2geom/src/toys/find-derivative.cpp | 500 |
1 files changed, 500 insertions, 0 deletions
diff --git a/src/3rdparty/2geom/src/toys/find-derivative.cpp b/src/3rdparty/2geom/src/toys/find-derivative.cpp new file mode 100644 index 0000000..e4c64f5 --- /dev/null +++ b/src/3rdparty/2geom/src/toys/find-derivative.cpp @@ -0,0 +1,500 @@ +#include <2geom/d2.h> +#include <2geom/sbasis.h> +#include <2geom/sbasis-2d.h> +#include <2geom/bezier-to-sbasis.h> +#include <2geom/sbasis-geometric.h> + +#include <toys/path-cairo.h> +#include <toys/toy-framework-2.h> + +#include <2geom/angle.h> + +using std::vector; +using namespace Geom; +using namespace std; + +// Author: Johan Engelen, 2009 +// +// Shows how to find the locations on a path where the derivative is parallel to a certain vector. +//----------------------------------------------- + + +std::string angle_formatter(double angle) +{ + return default_formatter(decimal_round(deg_from_rad(angle),2)); +} + + + +class FindDerivatives : public Toy +{ + enum menu_item_t + { + SHOW_MENU = 0, + TEST_CREATE, + TEST_PROJECTION, + TEST_ORTHO, + TEST_DISTANCE, + TEST_POSITION, + TEST_SEG_BISEC, + TEST_ANGLE_BISEC, + TEST_COLLINEAR, + TEST_INTERSECTIONS, + TEST_COEFFICIENTS, + TOTAL_ITEMS // this one must be the last item + }; + + enum handle_label_t + { + }; + + enum toggle_label_t + { + }; + + enum slider_label_t + { + END_SHARED_SLIDERS = 0, + ANGLE_SLIDER = END_SHARED_SLIDERS, + A_COEFF_SLIDER = END_SHARED_SLIDERS, + B_COEFF_SLIDER, + C_COEFF_SLIDER + }; + + static const char* menu_items[TOTAL_ITEMS]; + static const char keys[TOTAL_ITEMS]; + + PointSetHandle curve_handle; + PointHandle sample_point; + + void first_time(int /*argc*/, char** /*argv*/) override + { + draw_f = &FindDerivatives::draw_menu; + } + + void init_common() + { + set_common_control_geometry = true; + set_control_geometry = true; + + sliders.clear(); + toggles.clear(); + handles.clear(); + } + + + virtual void draw_common( cairo_t *cr, std::ostringstream *notify, + int width, int height, bool /*save*/ ) + { + init_common_ctrl_geom(cr, width, height, notify); + } + + + void init_create() + { + init_common(); + + p1.pos = Point(400, 50); + p2.pos = Point(450, 450); + O.pos = Point(50, 400); + + sliders.emplace_back(0, 2*M_PI, 0, 0, "angle"); + sliders[ANGLE_SLIDER].formatter(&angle_formatter); + + handles.push_back(&p1); + handles.push_back(&p2); + handles.push_back(&O); + handles.push_back(&(sliders[ANGLE_SLIDER])); + } + + void draw_create(cairo_t *cr, std::ostringstream *notify, + int width, int height, bool save, std::ostringstream */*timer_stream*/) + { + draw_common(cr, notify, width, height, save); + init_create_ctrl_geom(cr, notify, width, height); + + Line l1(p1.pos, p2.pos); + Line l2(O.pos, sliders[ANGLE_SLIDER].value()); + + cairo_set_source_rgba(cr, 0.0, 0.0, 0.0, 1.0); + cairo_set_line_width(cr, 0.3); + draw_line(cr, l1); + draw_line(cr, l2); + cairo_stroke(cr); + + draw_label(cr, p1, "P1"); + draw_label(cr, p2, "P2"); + draw_label(cr, O, "O"); + draw_label(cr, l1, "L(P1,P2)"); + draw_label(cr, l2, "L(O,angle)"); + } + + + void init_projection() + { + init_common(); + p1.pos = Point(400, 50); + p2.pos = Point(450, 450); + p3.pos = Point(100, 250); + p4.pos = Point(200, 450); + O.pos = Point(50, 150); + + handles.push_back(&p1); + handles.push_back(&p2); + handles.push_back(&p3); + handles.push_back(&p4); + handles.push_back(&O); + } + + void draw_projection(cairo_t *cr, std::ostringstream *notify, + int width, int height, bool save, std::ostringstream */*timer_stream*/) + { + draw_common(cr, notify, width, height, save); + + Line l1(p1.pos, p2.pos); + LineSegment ls(p3.pos, p4.pos); + + Point np = projection(O.pos, l1); + LineSegment lsp = projection(ls, l1); + + cairo_set_source_rgba(cr, 0.3, 0.3, 0.3, 1.0); + cairo_set_line_width(cr, 0.2); + draw_line(cr, l1); + draw_segment(cr, ls); + cairo_stroke(cr); + + cairo_set_line_width(cr, 0.3); + cairo_set_source_rgba(cr, 0.0, 0.0, 1.0, 1.0); + draw_segment(cr, lsp); + draw_handle(cr, lsp[0]); + draw_handle(cr, lsp[1]); + cairo_stroke(cr); + + cairo_set_source_rgba(cr, 0.8, 0.0, 0.0, 1.0); + draw_circ(cr, np); + cairo_stroke(cr); + + cairo_set_source_rgba(cr, 0.5, 0.5, 0.5, 1.0); + draw_label(cr, p1, "P1"); + draw_label(cr, p2, "P2"); + draw_label(cr, ls, "S"); + draw_label(cr, lsp, "prj(S)"); + draw_label(cr, O, "P"); + draw_text(cr, np, "prj(P)"); + + cairo_stroke(cr); + } + + void init_derivative() { + init_common(); + handles.push_back(&curve_handle); + handles.push_back(&sample_point); + for(unsigned i = 0; i < 4; i++) + curve_handle.push_back(150+uniform()*300,150+uniform()*300); + sample_point.pos = Geom::Point(250,300); + } + + void draw_derivative(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) { + + D2<SBasis> B = curve_handle.asBezier(); + + cairo_set_line_width (cr, 1); + cairo_set_source_rgba (cr, 0., 0.5, 0., 1); + cairo_d2_sb(cr, B); + cairo_stroke(cr); + + Point vector = sample_point.pos - Geom::Point(400,400); + cairo_move_to(cr, Geom::Point(400,400)); + cairo_line_to(cr, sample_point.pos); + cairo_set_source_rgba (cr, 0., 0., 0.5, 0.8); + cairo_stroke(cr); + + // How to find location of points with certain derivative along a path: + D2<SBasis> deriv = derivative(B); + SBasis dotp = dot(deriv, rot90(vector)); + std::vector<double> sol = roots(dotp); + for (double i : sol) { + draw_handle(cr, B.valueAt(i)); // the solutions are in vector 'sol' + } + + cairo_set_source_rgba (cr, 0.5, 0.2, 0., 0.8); + cairo_stroke(cr); + Toy::draw(cr, notify, width, height, save,timer_stream); + } + + void init_find_tangents() { + init_common(); + handles.push_back(&curve_handle); + handles.push_back(&sample_point); + + toggles.emplace_back(" tangent / normal ", false); + handles.push_back(&(toggles[0])); + for(unsigned i = 0; i < 4; i++) + curve_handle.push_back(150+uniform()*300,150+uniform()*300); + sample_point.pos = Geom::Point(250,300); + Point toggle_sp( 30, 30); + toggles[0].bounds = Rect( toggle_sp, toggle_sp + Point(200,25) ); + } + + void draw_find_tangents(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) { + + D2<SBasis> B = curve_handle.asBezier(); + + cairo_set_line_width (cr, 1); + cairo_set_source_rgba (cr, 0., 0.5, 0., 1); + cairo_d2_sb(cr, B); + cairo_stroke(cr); + + std::vector<double> sol = toggles[0].on ? + find_tangents(sample_point.pos, B) + : find_normals(sample_point.pos, B); + for (double i : sol) { + draw_handle(cr, B.valueAt(i)); // the solutions are in vector 'sol' + draw_segment(cr, B.valueAt(i), sample_point.pos); + } + + cairo_set_source_rgba (cr, 0.5, 0.2, 0., 0.8); + cairo_stroke(cr); + Toy::draw(cr, notify, width, height, save,timer_stream); + } + + void init_ortho() + { + init_common(); + p1.pos = Point(400, 50); + p2.pos = Point(450, 450); + p3.pos = Point(100, 50); + p4.pos = Point(150, 450); + + handles.push_back(&p1); + handles.push_back(&p2); + handles.push_back(&p3); + handles.push_back(&p4); + } + + void draw_ortho(cairo_t *cr, std::ostringstream *notify, + int width, int height, bool save, std::ostringstream */*timer_stream*/) + { + draw_common(cr, notify, width, height, save); + + Line l1(p1.pos, p2.pos); + Line l2 = make_orthogonal_line(p3.pos, l1); + Line l3 = make_parallel_line(p4.pos, l1); + + cairo_set_source_rgba(cr, 0.0, 0.0, 0.0, 1.0); + cairo_set_line_width(cr, 0.3); + draw_line(cr, l1); + draw_line(cr, l2); + draw_line(cr, l3); + cairo_stroke(cr); + + draw_label(cr, p1, "P1"); + draw_label(cr, p2, "P2"); + draw_label(cr, p3, "O1"); + draw_label(cr, p4, "O2"); + + draw_label(cr, l1, "L"); + draw_label(cr, l2, "L1 _|_ L"); + draw_label(cr, l3, "L2 // L"); + + } + + + + + void init_common_ctrl_geom(cairo_t* /*cr*/, int /*width*/, int /*height*/, std::ostringstream* /*notify*/) + { + if ( set_common_control_geometry ) + { + set_common_control_geometry = false; + } + } + + void init_create_ctrl_geom(cairo_t* /*cr*/, std::ostringstream* /*notify*/, int /*width*/, int height) + { + if ( set_control_geometry ) + { + set_control_geometry = false; + + sliders[ANGLE_SLIDER].geometry(Point(50, height - 50), 180); + } + } + + void init_coefficients_ctrl_geom(cairo_t* /*cr*/, std::ostringstream* /*notify*/, int /*width*/, int height) + { + if ( set_control_geometry ) + { + set_control_geometry = false; + + sliders[A_COEFF_SLIDER].geometry(Point(50, height - 160), 400); + sliders[B_COEFF_SLIDER].geometry(Point(50, height - 110), 400); + sliders[C_COEFF_SLIDER].geometry(Point(50, height - 60), 400); + } + } + + + void draw_segment(cairo_t* cr, Point const& p1, Point const& p2) + { + cairo_move_to(cr, p1); + cairo_line_to(cr, p2); + } + + void draw_segment(cairo_t* cr, Point const& p1, double angle, double length) + { + Point p2; + p2[X] = length * std::cos(angle); + p2[Y] = length * std::sin(angle); + p2 += p1; + draw_segment(cr, p1, p2); + } + + void draw_segment(cairo_t* cr, LineSegment const& ls) + { + draw_segment(cr, ls[0], ls[1]); + } + + void draw_ray(cairo_t* cr, Ray const& r) + { + double angle = r.angle(); + draw_segment(cr, r.origin(), angle, m_length); + } + + void draw_line(cairo_t* cr, Line const& l) + { + double angle = l.angle(); + draw_segment(cr, l.origin(), angle, m_length); + draw_segment(cr, l.origin(), angle, -m_length); + } + + void draw_label(cairo_t* cr, PointHandle const& ph, const char* label) + { + draw_text(cr, ph.pos+op, label); + } + + void draw_label(cairo_t* cr, Line const& l, const char* label) + { + draw_text(cr, projection(Point(m_width/2-30, m_height/2-30), l)+op, label); + } + + void draw_label(cairo_t* cr, LineSegment const& ls, const char* label) + { + draw_text(cr, middle_point(ls[0], ls[1])+op, label); + } + + void draw_label(cairo_t* cr, Ray const& r, const char* label) + { + Point prj = r.pointAt(r.nearestTime(Point(m_width/2-30, m_height/2-30))); + if (L2(r.origin() - prj) < 100) + { + prj = r.origin() + 100*r.vector(); + } + draw_text(cr, prj+op, label); + } + + void init_menu() + { + handles.clear(); + sliders.clear(); + toggles.clear(); + } + + void draw_menu( cairo_t * /*cr*/, std::ostringstream *notify, + int /*width*/, int /*height*/, bool /*save*/, + std::ostringstream */*timer_stream*/ ) + { + *notify << std::endl; + for (int i = SHOW_MENU; i < TOTAL_ITEMS; ++i) + { + *notify << " " << keys[i] << " - " << menu_items[i] << std::endl; + } + } + + void key_hit(GdkEventKey *e) override + { + char choice = std::toupper(e->keyval); + switch ( choice ) + { + case 'A': + init_menu(); + draw_f = &FindDerivatives::draw_menu; + break; + case 'B': + init_derivative(); + draw_f = &FindDerivatives::draw_derivative; + break; + case 'C': + init_find_tangents(); + draw_f = &FindDerivatives::draw_find_tangents; + break; + case 'D': + init_ortho(); + draw_f = &FindDerivatives::draw_ortho; + break; + } + redraw(); + } + + void draw( cairo_t *cr, std::ostringstream *notify, + int width, int height, bool save, std::ostringstream *timer_stream) override + { + m_width = width; + m_height = height; + m_length = (m_width > m_height) ? m_width : m_height; + m_length *= 2; + (this->*draw_f)(cr, notify, width, height, save, timer_stream); + Toy::draw(cr, notify, width, height, save, timer_stream); + } + + public: + FindDerivatives() + { + op = Point(5,5); + } + + private: + typedef void (FindDerivatives::* draw_func_t) (cairo_t*, std::ostringstream*, int, int, bool, std::ostringstream*); + draw_func_t draw_f; + bool set_common_control_geometry; + bool set_control_geometry; + PointHandle p1, p2, p3, p4, p5, p6, O; + std::vector<Toggle> toggles; + std::vector<Slider> sliders; + Point op; + double m_width, m_height, m_length; + +}; // end class FindDerivatives + + +const char* FindDerivatives::menu_items[] = +{ + "show this menu", + "derivative matching on curve", + "find normals", + "find tangents" +}; + +const char FindDerivatives::keys[] = +{ + 'A', 'B', 'C', 'D' +}; + + + +int main(int argc, char **argv) +{ + init( argc, argv, new FindDerivatives()); + return 0; +} + +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +//vim:expandtab:shiftwidth = 4:tabstop = 8:softtabstop = 4:encoding = utf-8:textwidth = 99 : + + |