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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/worms.cpp
parentInitial commit. (diff)
downloadlib2geom-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.cpp138
1 files changed, 138 insertions, 0 deletions
diff --git a/src/toys/worms.cpp b/src/toys/worms.cpp
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+++ b/src/toys/worms.cpp
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+#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 :