Patch from codedread. Prevents rendering of title/desc/metadata elements in text...

[inkscape.git] / src / line-geometry.h

diff --git a/src/line-geometry.h b/src/line-geometry.h
index 53f39db39f8dbd534c16a17725f70a4f655f8546..5e3152c03c97e44e9f4be6b32cdf559af56db5d6 100644 (file)
--- a/src/line-geometry.h
+++ b/src/line-geometry.h
@@ -17,7 +17,7 @@
 #include "libnr/nr-maybe.h"
 #include "glib.h"
 #include "display/sp-ctrlline.h"
-#include "vanishing-point.h"
+#include "axis-manip.h" // FIXME: This is only for Box3D::epsilon; move that to a better location
 
 #include "document.h"
 #include "ui/view/view.h"
@@ -28,30 +28,59 @@ class Line {
 public:
     Line(NR::Point const &start, NR::Point const &vec, bool is_endpoint = true);
     Line(Line const &line);
+    virtual ~Line() {}
     Line &operator=(Line const &line);
     virtual NR::Maybe<NR::Point> intersect(Line const &line);
-    void set_direction(NR::Point const &dir); // FIXME: Can we avoid this explicit assignment?
+    inline NR::Point direction () { return v_dir; }
     
     NR::Point closest_to(NR::Point const &pt); // returns the point on the line closest to pt 
 
     friend inline std::ostream &operator<< (std::ostream &out_file, const Line &in_line);
-       
-private:
+    NR::Maybe<NR::Point> intersection_with_viewbox (SPDesktop *desktop);
+    inline bool lie_on_same_side (NR::Point const &A, NR::Point const &B) {
+        /* If A is a point in the plane and n is the normal vector of the line then
+           the sign of dot(A, n) specifies the half-plane in which A lies.
+           Thus A and B lie on the same side if the dot products have equal sign. */
+        return ((NR::dot(A, normal) - d0) * (NR::dot(B, normal) - d0)) > 0;
+    }
+
+    double lambda (NR::Point const pt);
+    inline NR::Point point_from_lambda (double const lambda) { 
+        return (pt + lambda * NR::unit_vector (v_dir)); }
+
+protected:
+    void set_direction(NR::Point const &dir);
+    inline static bool pts_coincide (NR::Point const pt1, NR::Point const pt2)
+    {
+        return (NR::L2 (pt2 - pt1) < epsilon);
+    }
+
     NR::Point pt;
     NR::Point v_dir;
     NR::Point normal;
     NR::Coord d0;
 };
 
-/*** For testing purposes: Draw a knot/node of specified size and color at the given position ***/
+inline double determinant (NR::Point const &a, NR::Point const &b)
+{
+    return (a[NR::X] * b[NR::Y] - a[NR::Y] * b[NR::X]);
+}
+std::pair<double, double> coordinates (NR::Point const &v1, NR::Point const &v2, NR::Point const &w);
+bool lies_in_sector (NR::Point const &v1, NR::Point const &v2, NR::Point const &w);
+bool lies_in_quadrangle (NR::Point const &A, NR::Point const &B, NR::Point const &C, NR::Point const &D, NR::Point const &pt);
+std::pair<NR::Point, NR::Point> side_of_intersection (NR::Point const &A, NR::Point const &B,
+                                                      NR::Point const &C, NR::Point const &D,
+                                                      NR::Point const &pt, NR::Point const &dir);
+
+/*** For debugging purposes: Draw a knot/node of specified size and color at the given position ***/
 void create_canvas_point(NR::Point const &pos, double size = 4.0, guint32 rgba = 0xff00007f);
 
-/*** For testing purposes: Draw a line between the specified points ***/
+/*** For debugging purposes: Draw a line between the specified points ***/
 void create_canvas_line(NR::Point const &p1, NR::Point const &p2, guint32 rgba = 0xff00007f);
 
 
-/** A function to print out the Line.  It just prints out the coordinates of start end end point
-    on the given output stream */
+/** A function to print out the Line.  It just prints out the coordinates of start point and
+    direction on the given output stream */
 inline std::ostream &operator<< (std::ostream &out_file, const Line &in_line) {
     out_file << "Start: " << in_line.pt << "  Direction: " << in_line.v_dir;
     return out_file;