Add translator hint.

[inkscape.git] / src / libnr / nr-rect.h

diff --git a/src/libnr/nr-rect.h b/src/libnr/nr-rect.h
index 5e2332bf278315765af1a0d850e628f04e0275fc..46aff13f4fa938212f39df8654abeaacd1cdcaf5 100644 (file)
--- a/src/libnr/nr-rect.h
+++ b/src/libnr/nr-rect.h
@@ -31,9 +31,10 @@ namespace NR {
 /** A rectangle is always aligned to the X and Y axis.  This means it
  * can be defined using only 4 coordinates, and determining
  * intersection is very efficient.  The points inside a rectangle are
- * min[dim] <= _pt[dim] <= max[dim].  Emptiness, however, is defined
- * as having zero area, meaning an empty rectangle may still contain
- * points.  Infinities are also permitted. */
+ * min[dim] <= _pt[dim] <= max[dim].  A rectangle may be empty, in the
+ * sense of having zero area, but it will always contain at least one
+ * point.  Infinities are also permitted.
+ */
 class Rect {
 public:
     Rect() : _min(-_inf(), -_inf()), _max(_inf(), _inf()) {}
@@ -52,9 +53,9 @@ public:
     /** returns the midpoint of this rect. */
     Point midpoint() const;
 
-    /** does this rectangle have zero area? */
-    bool isEmpty() const {
-        return isEmpty<X>() || isEmpty<Y>();
+    /** True iff either width or height is less than \a epsilon. */
+    bool isEmpty(double epsilon=1e-6) const {
+        return isEmpty<X>(epsilon) || isEmpty<Y>(epsilon);
     }
 
     bool intersects(Rect const &r) const {
@@ -125,6 +126,8 @@ public:
         _max[NR::Y] += by;
     }
 
+    void growBy (gdouble by);
+
     /** Scales the rect by s, with origin at 0, 0 */
     inline Rect operator*(double const s) const {
         return Rect(s * min(), s * max());
@@ -153,9 +156,9 @@ private:
         return _max[axis] - _min[axis];
     }
 
-    template <Dim2 axis>
-    bool isEmpty() const {
-        return !( _min[axis] < _max[axis] );
+    template <NR::Dim2 axis>
+    bool isEmpty(double epsilon) const {
+        return extent<axis>() < epsilon;
     }
 
     template <Dim2 axis>
@@ -176,6 +179,8 @@ private:
     Point _min, _max;
 
     friend class MaybeStorage<Rect>;
+    friend Maybe<Rect> intersection(Maybe<Rect> const &, Maybe<Rect> const &);
+    friend Rect union_bounds(Rect const &, Rect const &);
 };
 
 template <>
@@ -195,25 +200,25 @@ private:
 };
 
 /** Returns the set of points shared by both rectangles. */
-Maybe<Rect> intersection(Maybe<Rect const &> a, Maybe<Rect const &> b);
+Maybe<Rect> intersection(Maybe<Rect> const & a, Maybe<Rect> const & b);
 
 /** Returns the smallest rectangle that encloses both rectangles. */
 Rect union_bounds(Rect const &a, Rect const &b);
-inline Rect union_bounds(Maybe<Rect const &> a, Rect const &b) {
+inline Rect union_bounds(Maybe<Rect> const & a, Rect const &b) {
     if (a) {
         return union_bounds(*a, b);
     } else {
         return b;
     }
 }
-inline Rect union_bounds(Rect const &a, Maybe<Rect const &> b) {
+inline Rect union_bounds(Rect const &a, Maybe<Rect> const & b) {
     if (b) {
         return union_bounds(a, *b);
     } else {
         return a;
     }
 }
-inline Maybe<Rect> union_bounds(Maybe<Rect const &> a, Maybe<Rect const &> b)
+inline Maybe<Rect> union_bounds(Maybe<Rect> const & a, Maybe<Rect> const & b)
 {
     if (!a) {
         return b;
@@ -260,6 +265,7 @@ struct NRRect {
 #define nr_rect_d_set_empty(r) (*(r) = NR_RECT_EMPTY)
 #define nr_rect_l_set_empty(r) (*(r) = NR_RECT_L_EMPTY)
 
+/** "Empty" here includes the case of zero width or zero height. */
 #define nr_rect_d_test_empty(r) ((r) && NR_RECT_DFLS_TEST_EMPTY(r))
 #define nr_rect_l_test_empty(r) ((r) && NR_RECT_DFLS_TEST_EMPTY(r))