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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/sb1d.cpp
parentInitial commit. (diff)
downloadlib2geom-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.cpp125
1 files changed, 125 insertions, 0 deletions
diff --git a/src/toys/sb1d.cpp b/src/toys/sb1d.cpp
new file mode 100644
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+++ 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 :