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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 11:57:42 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 11:57:42 +0000 |
commit | 61f3ab8f23f4c924d455757bf3e65f8487521b5a (patch) | |
tree | 885599a36a308f422af98616bc733a0494fe149a /src/toys/conic-4.cpp | |
parent | Initial commit. (diff) | |
download | lib2geom-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.cpp | 129 |
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 : |