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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-3.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-3.cpp')
-rw-r--r-- | src/toys/conic-3.cpp | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/src/toys/conic-3.cpp b/src/toys/conic-3.cpp new file mode 100644 index 0000000..64b2c27 --- /dev/null +++ b/src/toys/conic-3.cpp @@ -0,0 +1,96 @@ +/** + * 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 : |