diff options
Diffstat (limited to '2d/rect.scm')
-rw-r--r-- | 2d/rect.scm | 54 |
1 files changed, 49 insertions, 5 deletions
diff --git a/2d/rect.scm b/2d/rect.scm index bbccc0e..1257142 100644 --- a/2d/rect.scm +++ b/2d/rect.scm @@ -24,6 +24,7 @@ (define-module (2d rect) #:use-module (srfi srfi-9) + #:use-module (2d vector2) #:export (<rect> make-rect rect? @@ -33,6 +34,8 @@ rect-y2 rect-width rect-height + rect-position + rect-size rect-move rect-inflate rect-union @@ -41,6 +44,10 @@ rect-intesects? rect-contains?)) +;;; +;;; Rectangles +;;; + ;; The rect API is very similar to the Pygame rect API, but rects are ;; immutable. @@ -58,14 +65,34 @@ (define (rect-y2 rect) (+ (rect-y rect) (rect-height rect) -1)) -(define (rect-move rect x y) - "Moves a rect by the given offset." +(define (rect-position rect) + "Return the top-left corner of RECT as a vector2." + (vector2 (rect-x rect) + (rect-y rect))) + +(define (rect-size rect) + "Return the size of RECT as a vector2." + (vector2 (rect-width rect) + (rect-height rect))) + +(define (%rect-move rect x y) + "Move a rect by the given offset." (make-rect (+ (rect-x rect) x) (+ (rect-y rect) y) (rect-width rect) (rect-height rect))) -(define (rect-inflate rect width height) +(define rect-move + (case-lambda + "Create a new rectangle by moving RECT by the given +offset. rect-move accepts a vector2 or x and y coordinates as separate +arguments." + ((rect v) + (%rect-move rect (vx v) (vy v))) + ((rect x y) + (%rect-move rect x y)))) + +(define (%rect-inflate rect width height) "Grows the rect by the given amount. The rect stays centered around its current center." (make-rect (+ (rect-x rect) (/ width 2)) @@ -73,6 +100,16 @@ its current center." (+ (rect-width rect) width) (+ (rect-height rect) height))) +(define rect-inflate + (case-lambda + "Create a new rectangle by growing RECT by the given amount +without changing the center point. rect-inflate accepts a vector2 or x +and y coordinates as separate arguments." + ((rect v) + (%rect-inflate rect (vx v) (vy v))) + ((rect x y) + (%rect-inflate rect x y)))) + (define (rect-union rect1 rect2) "Returns a rect that covers the area of rect1 and rect2." (let ((x1 (min (rect-x rect1) (rect-x rect2))) @@ -112,9 +149,16 @@ not overlap, a rect of size 0 is returned." (and (>= (rect-y2 rect2) (rect-y rect1)) (<= (rect-y2 rect2) (rect-y2 rect1))))) -(define (rect-contains? rect x y) - "Tests if the given point is within rect." +(define (%rect-contains? rect x y) (and (>= x (rect-x rect)) (<= x (rect-x2 rect)) (>= y (rect-y rect)) (<= y (rect-y2 rect)))) + +(define rect-contains? + (case-lambda + "Tests if the given point is within rect." + ((rect v) + (%rect-contains? rect (vx v) (vy v))) + ((rect x y) + (%rect-contains? rect x y)))) |