summaryrefslogtreecommitdiffstats
path: root/src/toys/conic-4.cpp
diff options
context:
space:
mode:
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-4.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-4.cpp')
-rw-r--r--src/toys/conic-4.cpp129
1 files changed, 129 insertions, 0 deletions
diff --git a/src/toys/conic-4.cpp b/src/toys/conic-4.cpp
new file mode 100644
index 0000000..0dbecd6
--- /dev/null
+++ b/src/toys/conic-4.cpp
@@ -0,0 +1,129 @@
+/**
+ * elliptics via 5 point w-pi basis. (njh)
+ * Affine, endpoint, tangent, exact circle
+ * full circle. Convex containment implies small circle.
+ * Also represents lumpy polar type curves
+ */
+
+#include <2geom/d2.h>
+#include <2geom/sbasis.h>
+#include <2geom/sbasis-math.h>
+#include <2geom/bezier-to-sbasis.h>
+
+#include <toys/path-cairo.h>
+#include <toys/toy-framework-2.h>
+
+using std::vector;
+using namespace Geom;
+
+const double w = 1./3;
+const double cwp = cos(w*M_PI);
+const double swp = sin(w*M_PI);
+/*double phi(double t, double w) { return sin(w*t) - w*sin(t); }
+double phih(double t, double w) { return sin(w*t) + w*sin(t); }
+double b4(double t, double w) {return phi(t/2,w)*phih(t/2,w)/(swp*swp);}
+double b3(double t, double w) {return cwp*phi(t,w)/(2*swp) - cwp*cwp*b4(t,w); }
+double b2(double t, double w) {return 2*w*w*sin(t/2)*sin(t/2);}
+double b1(double t, double w) {return b3(2*M_PI - t, w);}
+double b0(double t, double w) {return b4(2*M_PI - t, w);}*/
+
+class arc_basis{
+public:
+ Piecewise<SBasis> basis[5];
+ double w;
+
+ Piecewise<SBasis> phi(Piecewise<SBasis> const &d, double w) {
+ return sin(d*w) - sin(d)*w;
+ }
+ Piecewise<SBasis> phih(Piecewise<SBasis> const &d, double w) {
+ return sin(d*w) + sin(d)*w;
+ }
+ Piecewise<SBasis> b4(Piecewise<SBasis> const &d, double w) {
+ return phi(d*.5,w)/(swp*swp)*phih(d*.5,w);
+ }
+ Piecewise<SBasis> b3(Piecewise<SBasis> const &d, double w) {
+ return phi(d,w)*(cwp/(2*swp)) - b4(d,w)*(cwp*cwp);
+ }
+
+ Piecewise<SBasis> b2(Piecewise<SBasis> const &d, double w) {
+ return sin(d*.5)*(2*w*w)*sin(d*.5);
+ }
+ Piecewise<SBasis> b1(Piecewise<SBasis> const &d, double w) {
+ return b3(reverse(d), w);
+ }
+ Piecewise<SBasis> b0(Piecewise<SBasis> const &d, double w) {
+ return b4(reverse(d), w);
+ }
+
+
+ arc_basis(double w) {
+ Piecewise<SBasis> dom(Linear(0, 2*M_PI));
+ basis[0] = b4(dom, w);
+ basis[1] = b3(dom, w);
+ basis[2] = b2(dom, w);
+ basis[3] = b1(dom, w);
+ basis[4] = b0(dom, w);
+ }
+
+};
+
+class Conic4: public Toy {
+ PointSetHandle psh;
+ public:
+ Conic4 () {
+ double sc = 30;
+ Geom::Point c(6*sc, 6*sc);
+ psh.push_back(sc*Geom::Point(0,0)+c);
+ psh.push_back(sc*Geom::Point(tan(w*M_PI)/w, 0)+c);
+ psh.push_back(sc*Geom::Point(0, 1/(w*w))+c);
+ psh.push_back(sc*Geom::Point(-tan(w*M_PI)/w, 0)+c);
+ psh.push_back(sc*Geom::Point(0,0)+c);
+ handles.push_back(&psh);
+ }
+
+ void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
+ std::vector<Geom::Point> e_h = psh.pts;
+ for(int i = 0; i < 5; i++) {
+ Geom::Point p = e_h[i];
+
+ if(i)
+ cairo_line_to(cr, p);
+ else
+ cairo_move_to(cr, p);
+ }
+ cairo_set_source_rgba (cr, 0., 0., 0, 1);
+ cairo_set_line_width (cr, 1);
+ cairo_stroke(cr);
+
+ arc_basis ab(1./3);
+ D2<Piecewise<SBasis> > B;
+
+ for(unsigned dim = 0; dim < 2; dim++)
+ for(unsigned i = 0; i < 5; i++)
+ B[dim] += ab.basis[i]*e_h[i][dim];
+
+ cairo_d2_pw_sb(cr, B);
+ cairo_set_source_rgba (cr, 1., 0.5, 0, 1);
+ cairo_set_line_width (cr, 1);
+ cairo_stroke(cr);
+
+ Toy::draw(cr, notify, width, height, save,timer_stream);
+ }
+};
+
+int main(int argc, char **argv) {
+ init(argc, argv, new Conic4());
+
+ 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 :