[refactor] paths points and enclosure [add] path encloses path test

2 files changed, 18 insertions, 4 deletions

diff --git a/src/utils.lisp b/src/utils.lisp
index 165f29a..bcb4cb2 100644
--- a/src/utils.lisp
+++ b/src/utils.lisp
@@ -41,8 +41,14 @@ and B intersects the linesegment between C and D, NIL otherwise."
                         while b2
                           thereis (segments-intersect-p a1 a2 b1 b2))))
 
-(defun path-contains-point (path pt)
+
+(defun closed-path-p (path)
+  (equalp (first path)
+          (first (last path))))
+
+(defun path-encloses-point-p (path pt)
   "Path is a list of vectors, pt is a single vector."
+  (assert (closed-path-p path) () "Enclosing path must be a closed path.")
   (let* ((bounds
            (path-bounds path))
          (corner
@@ -57,8 +63,16 @@ and B intersects the linesegment between C and D, NIL otherwise."
           finally
              (return (oddp intersection-count)))))
 
-(defun path-encloses-p (path other)
-  )
+
+
+(defun path-encloses-path-p (path-a path-b)
+  "T if path-b is totally contained in path-a and does not intersect path-a"
+  (assert (closed-path-p path-a) () "Enclosing path must be a closed path.")
+  (and 
+   (loop for (p1 p2 . more) on path-b
+         while p2
+         always (path-encloses-point-p path-a p1))
+   (not (paths-intersect-p path-a path-b))))
 
 (defun path-bounds (path)
   "Path is a list of vectors representing 2d points. Returns the
diff --git a/src/wheelwork.lisp b/src/wheelwork.lisp
index 983ecbe..8b1e534 100644
--- a/src/wheelwork.lisp
+++ b/src/wheelwork.lisp
@@ -66,7 +66,7 @@ TARGET is FOCUSABLEP"
                (sdl2:mod-keywords (sdl2:mod-value sdl-keysym)))))))
 
 (defun unit-contains-point-p (unit pt)
-  (path-contains-point (get-rect unit) pt))
+  (path-encloses-point-p (get-rect unit) pt))
 
 (defun unit-under (app x y)
   "Finds the visible unit that contains the point x y."