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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 11:57:42 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 11:57:42 +0000
commit61f3ab8f23f4c924d455757bf3e65f8487521b5a (patch)
tree885599a36a308f422af98616bc733a0494fe149a /src/toys/conic-3.cpp
parentInitial commit. (diff)
downloadlib2geom-61f3ab8f23f4c924d455757bf3e65f8487521b5a.tar.xz
lib2geom-61f3ab8f23f4c924d455757bf3e65f8487521b5a.zip
Adding upstream version 1.3.upstream/1.3upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/toys/conic-3.cpp')
-rw-r--r--src/toys/conic-3.cpp96
1 files changed, 96 insertions, 0 deletions
diff --git a/src/toys/conic-3.cpp b/src/toys/conic-3.cpp
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+/**
+ * elliptics via C-curves. (njh)
+ * Limited to 180 degrees (by end point and tangent matching criteria)
+ * Also represents cycloids
+ */
+
+#include <2geom/d2.h>
+#include <2geom/sbasis.h>
+#include <2geom/bezier-to-sbasis.h>
+#include <2geom/sbasis-to-bezier.h>
+#include <2geom/sbasis-math.h>
+
+#include <toys/path-cairo.h>
+#include <toys/toy-framework-2.h>
+
+using std::vector;
+using namespace Geom;
+
+Linear z0(0.5,1.);
+
+unsigned total_pieces;
+
+double sinC(double t) { return t - sin(t);}
+double cosC(double t) { return 1 - cos(t);}
+double tanC(double t) { return sinC(t) / cosC(t);}
+
+class Conic3: public Toy {
+ PointSetHandle psh;
+ public:
+ Conic3 () {
+ psh.push_back(100, 500);
+ psh.push_back(100, 500 - 200*M_PI/2);
+ psh.push_back(500, 500 - 200*M_PI/2);
+ psh.push_back(500, 500);
+ handles.push_back(&psh);
+ }
+
+ void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
+ cairo_set_source_rgba (cr, 0., 0., 0, 0.8);
+ cairo_set_line_width (cr, 0.5);
+ cairo_stroke(cr);
+
+ Geom::Point a[2] = {psh.pts[0] - psh.pts[1],
+ psh.pts[2] - psh.pts[1]};
+ double angle = Geom::angle_between(a[0], a[1]);
+ double len = std::max(Geom::L2(a[0]),
+ Geom::L2(a[1]));
+ for(auto & i : a)
+ i = len*unit_vector(i);
+ *notify << "angle = " << angle;
+ *notify << " sinC = " << sinC(angle);
+ *notify << " cosC = " << cosC(angle);
+ *notify << " tanC = " << tanC(angle);
+ vector<Geom::Point> e_a_h = psh.pts;
+
+ double alpha = M_PI;
+ Piecewise<SBasis> pw(Linear(0, alpha));
+ Piecewise<SBasis> C = cos(pw);
+ Piecewise<SBasis> S = sin(pw);
+ Piecewise<SBasis> sinC = pw - S;
+ Piecewise<SBasis> cosC = Piecewise<SBasis>(1) - C;
+ Piecewise<SBasis> Z3 = sinC/sinC(1);
+ Piecewise<SBasis> Z0 = reverse(Z3);
+ Piecewise<SBasis> Z2 = cosC/cosC(1) - Z3;
+ Piecewise<SBasis> Z1 = reverse(Z2);
+
+ Piecewise<SBasis> Z[4] = {Z0, Z1, Z2, Z3};
+
+ D2<Piecewise<SBasis> > B;
+ for(unsigned dim = 0; dim < 2; dim++) {
+ B[dim] = Piecewise<SBasis>(0);
+ for(unsigned i = 0; i < 4; i++) {
+ B[dim] += Z[i]*e_a_h[i][dim];
+ }
+ }
+ cairo_d2_pw_sb(cr, B);
+ Toy::draw(cr, notify, width, height, save,timer_stream);
+ }
+};
+
+int main(int argc, char **argv) {
+ init(argc, argv, new Conic3());
+
+ 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: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :