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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/worms.cpp | |
parent | Initial commit. (diff) | |
download | lib2geom-upstream.tar.xz lib2geom-upstream.zip |
Adding upstream version 1.3.upstream/1.3upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/toys/worms.cpp')
-rw-r--r-- | src/toys/worms.cpp | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/src/toys/worms.cpp b/src/toys/worms.cpp new file mode 100644 index 0000000..81e7558 --- /dev/null +++ b/src/toys/worms.cpp @@ -0,0 +1,138 @@ +#include <2geom/d2.h> +#include <2geom/sbasis.h> +#include <2geom/sbasis-geometric.h> +#include <2geom/svg-path-parser.h> +#include <2geom/sbasis-math.h> + +#include <toys/path-cairo.h> +#include <toys/toy-framework-2.h> + +//Random walkers toy, written by mgsloan, initially for a school video proj. + +using namespace Geom; + +static void dot_plot(cairo_t *cr, Piecewise<D2<SBasis> > const &M, double min, double max, double space=10){ + for( double t = min; t < max; t += space) { + Point pos = M(t), perp = M.valueAndDerivatives(t, 2)[1].cw() * 3; + draw_line_seg(cr, pos + perp, pos - perp); + } + cairo_stroke(cr); +} + +D2<SBasis> random_d2() { + D2<SBasis> ret(SBasis(6, Linear()), + SBasis(6, Linear())); + ret[0][0] = Linear(uniform()*720, uniform()*720); + ret[1][0] = Linear(uniform()*480, uniform()*480); + + int mul = 1; + for(int i = 1; i < 6; i++) { + ret[0][i] = Linear(uniform()*2000*mul - 1000, uniform()*2000*mul - 1000); + ret[1][i] = Linear(uniform()*2000*mul - 1000, uniform()*2000*mul - 1000); + mul*=2; + } + return ret; +} + +class Worm { + Piecewise<D2<SBasis> > path; + int spawn_time, last_time; + double red, green, blue, length; + public: + void tele(int t) { + Piecewise<D2<SBasis> > new_path(portion(path, 0, t - last_time)); + new_path.push(random_d2(), path.domain().max()+1); + path = arc_length_parametrization(new_path); + } + void add_section(const D2<SBasis> x) { + Piecewise<D2<SBasis> > new_path(path); + D2<SBasis> seg(x); + seg[0][0][0] = path.segs.back()[0][0][1]; + seg[1][0][0] = path.segs.back()[1][0][1]; + new_path.push(seg, path.domain().max()+1); + path = arc_length_parametrization(new_path); + } + Worm (int t, double r, double g, double b, double l) : spawn_time(t), last_time(t), red(r), green(g), blue(b), length(l) { + path = Piecewise<D2<SBasis> >(random_d2()); + add_section(random_d2()); + } + void draw(cairo_t *cr, int t) { + if(t - last_time > path.domain().max()) add_section(random_d2()); + if(t - last_time - length > path.cuts[1]) { + Piecewise<D2<SBasis> > new_path; + new_path.push_cut(0); + for(unsigned i = 1; i < path.size(); i++) { + new_path.push(path[i], path.cuts[i+1] - path.cuts[1]); + } + last_time = t - length; + path = new_path; + } + cairo_set_source_rgb(cr, red, green, blue); + Piecewise<D2<SBasis> > port = portion(path, std::max(t - last_time - length, 0.), t - last_time); + cairo_pw_d2_sb(cr, port); + cairo_stroke(cr); + + double d = 4; + cairo_set_dash(cr, &d, 1, 0); + for(unsigned i = 1; i < path.size(); i++) { + if(path[i].at0() != path[i-1].at1()) { + draw_line_seg(cr, path[i].at0(), path[i-1].at1()); + } + } + cairo_stroke(cr); + cairo_set_dash(cr, &d, 0, 0); + + cairo_set_source_rgb(cr, 0., 0., 1.); + dot_plot(cr, path, std::max(t - last_time - length, 0.), t - last_time); + } + void reverse_direction(int t) { + path = portion(path, 0, t - last_time); + D2<SBasis> seg = random_d2(), last = path[path.size()-1]; + for(unsigned c = 0; c < 2; c++) + for(unsigned d = 1; d < seg[c].size() && d < last[c].size(); d++) + seg[c][d][0] = -last[c][d][1]; + add_section(seg); + } +}; + +class Intro: public Toy { + int t; + vector<Worm> worms; + void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override { + t++; + if(t < 40 && t % 2 == 0) { + worms.emplace_back(t, uniform(), uniform(), uniform(), uniform() * 200 + 50); + } + + for(auto & worm : worms) { + worm.draw(cr, t); + if(uniform() > .999) worm.tele(t); + } + + Toy::draw(cr, notify, width, height, save,timer_stream); + redraw(); + } + + int should_draw_bounds() override { return 0; } + + public: + Intro () { + t = 0; + } +}; + +int main(int argc, char **argv) { + init(argc, argv, new Intro(), 720, 480); + 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 : |