diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 11:57:42 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 11:57:42 +0000 |
commit | 61f3ab8f23f4c924d455757bf3e65f8487521b5a (patch) | |
tree | 885599a36a308f422af98616bc733a0494fe149a /src/toys/sb1d.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/sb1d.cpp')
-rw-r--r-- | src/toys/sb1d.cpp | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/src/toys/sb1d.cpp b/src/toys/sb1d.cpp new file mode 100644 index 0000000..dabbebb --- /dev/null +++ b/src/toys/sb1d.cpp @@ -0,0 +1,125 @@ +#include <2geom/d2.h> +#include <2geom/sbasis.h> +#include <2geom/sbasis-2d.h> +#include <2geom/bezier-to-sbasis.h> +#include <2geom/choose.h> +#include <2geom/convex-hull.h> + +#include <2geom/path.h> + +#include <toys/path-cairo.h> +#include <toys/toy-framework-2.h> + +#include <vector> +using std::vector; +using namespace Geom; + +extern unsigned total_steps, total_subs; + +double& handle_to_sb(unsigned i, unsigned n, SBasis &sb) { + assert(i < n); + assert(n <= sb.size()*2); + unsigned k = i; + if(k >= n/2) { + k = n - k - 1; + return sb[k][1]; + } else + return sb[k][0]; +} + +double handle_to_sb_t(unsigned i, unsigned n) { + double k = i; + if(i >= n/2) + k = n - k - 1; + double t = k/(2*k+1); + if(i >= n/2) + return 1 - t; + else + return t; +} + +class Sb1d: public Toy { +public: + PointSetHandle hand; + 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., 0.5, 0, 1); + cairo_set_line_width (cr, 1); + + if(!save) { + for(unsigned i = 0; i < hand.pts.size(); i++) { + hand.pts[i][0] = width*handle_to_sb_t(i, hand.pts.size())/2 + width/4; + if(i) + cairo_line_to(cr, hand.pts[i]); + else + cairo_move_to(cr, hand.pts[i]); + } + } + + D2<SBasis> B; + B[0] = Linear(width/4, 3*width/4); + B[1].resize(hand.pts.size()/2); + for(auto & i : B) { + i = Linear(0); + } + for(unsigned i = 0; i < hand.pts.size(); i++) { + handle_to_sb(i, hand.pts.size(), B[1]) = 3*width/4 - hand.pts[i][1]; + } + for(unsigned i = 1; i < B[1].size(); i++) { + B[1][i] = B[1][i]*choose<double>(2*i+1, i); + } + + Interval bs = *bounds_fast(B[1]); + double lo, hi; + lo = 3*width/4 - bs.min(); + hi = 3*width/4 - bs.max(); + cairo_move_to(cr, B[0](0), lo); + cairo_line_to(cr, B[0](1), lo); + cairo_move_to(cr, B[0](0), hi); + cairo_line_to(cr, B[0](1), hi); + cairo_stroke(cr); + *notify << "sb bounds = "<<lo << ", " <<hi<<std::endl; + //B[1] = SBasis(Linear(3*width/4)) - B[1]; + *notify << B[0] << ", "; + *notify << B[1]; + Geom::Path pb; + B[1] = SBasis(Linear(3*width/4)) - B[1]; + pb.append(B); + pb.close(false); + cairo_path(cr, pb); + + cairo_set_source_rgba (cr, 0., 0.125, 0, 1); + cairo_stroke(cr); + + Geom::ConvexHull ch(hand.pts); + + cairo_move_to(cr, ch.back()); + for(auto i : ch) { + cairo_line_to(cr, i); + } + Toy::draw(cr, notify, width, height, save,timer_stream); + } +public: +Sb1d () { + hand.pts.emplace_back(0,450); + for(unsigned i = 0; i < 4; i++) + hand.pts.emplace_back(uniform()*400, uniform()*400); + hand.pts.emplace_back(0,450); + handles.push_back(&hand); +} +}; + +int main(int argc, char **argv) { + init(argc, argv, new Sb1d()); + 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=4:softtabstop=4:fileencoding=utf-8:textwidth=99 : |