From 4eb732101deeac9da11449cc565967fcd2fc8f99 Mon Sep 17 00:00:00 2001
From: Stephen Chang <stchang@ccs.neu.edu>
Date: Thu, 4 Jun 2015 13:49:20 -0400
Subject: [PATCH] whalesong/image rotate accepts any real num

---
 whalesong/image/private/js-impl.js | 20 ++++++++------------
 whalesong/image/private/kernel.js  |  9 ++++-----
 whalesong/tests/test-images.rkt    | 30 ++++++++++++++++++++++++++++--
 3 files changed, 40 insertions(+), 19 deletions(-)

diff --git a/whalesong/image/private/js-impl.js b/whalesong/image/private/js-impl.js
index 3802c7e..52f6756 100644
--- a/whalesong/image/private/js-impl.js
+++ b/whalesong/image/private/js-impl.js
@@ -89,8 +89,6 @@ var less = function(lhs, rhs) {
   return (rhs - lhs) > 0.00001;
 }
 
-
-
 var checkString = plt.baselib.check.checkString;
 var checkStringOrFalse = plt.baselib.check.makeCheckArgumentType(
     function(x) { return plt.baselib.strings.isString(x) || x === false; },
@@ -782,28 +780,26 @@ EXPORTS['place-image/align'] =
             }
         });
 
-
-
-
-
-
-
+//////////////////////////////////////////////////////////////////////
+// rotate: angle image -> image
+// Rotates image by angle degrees in a counter-clockwise direction.
 EXPORTS['rotate'] = 
     makePrimitiveProcedure(
         'rotate',
         2,
         function(MACHINE) {
 	    var angle = checkRotateAngle(MACHINE, "rotate", 0);
+	    var angle360 = angle % 360;
 	    var img = checkImage(MACHINE, "rotate", 1);
-            if (jsnums.lessThan(angle, 0)) {
-		return makeRotateImage(jsnums.toFixnum(-(360 + angle)), img);
+	    // convert to clockwise rotation for makeRotateImage
+	    if (angle360 < 0) {
+		return makeRotateImage(jsnums.toFixnum(-(360 + angle360)), img);
 	    } else {
-		return makeRotateImage(jsnums.toFixnum(-angle), img);
+		return makeRotateImage(jsnums.toFixnum(-angle360), img);
 	    }
         });
 
 
-
 EXPORTS['scale'] = 
     makePrimitiveProcedure(
         'scale',
diff --git a/whalesong/image/private/kernel.js b/whalesong/image/private/kernel.js
index fdd03b0..48ca739 100644
--- a/whalesong/image/private/kernel.js
+++ b/whalesong/image/private/kernel.js
@@ -28,9 +28,7 @@ var isAngle = function(x) {
 };
 // differentiate between rotation angle and other angles
 var isRotateAngle = function(x) {
-    return plt.baselib.numbers.isReal(x) &&
-        jsnums.greaterThan(x, -360) &&
-        jsnums.lessThan(x, 360);
+    return plt.baselib.numbers.isReal(x);
 };
 
 
@@ -672,8 +670,9 @@ OverlayImage.prototype.equals = function(other, aUnionFind) {
 
 
 //////////////////////////////////////////////////////////////////////
-// rotate: angle image -> image
-// Rotates image by angle degrees in a counter-clockwise direction.
+// RotateImage: angle image -> image
+// Rotates image by angle degrees in a *clockwise* direction.
+// NOTE: the angle direction differs from the rotate function.
 // TODO: special case for ellipse?
 var RotateImage = function(angle, img) {
   BaseImage.call(this);
diff --git a/whalesong/tests/test-images.rkt b/whalesong/tests/test-images.rkt
index ef3a8e8..ecd7d62 100644
--- a/whalesong/tests/test-images.rkt
+++ b/whalesong/tests/test-images.rkt
@@ -601,8 +601,34 @@ Australia2
  (flip-horizontal
   (rotate 30 (square 50 "solid" "blue"))))
 
-"A solid blue triangle, rotated 30 degrees. Should be flush left"
-(rotate 30 (triangle 100 "solid" "blue"))
+(define blue-tri (triangle 100 "solid" "blue"))
+"A solid blue triangle, rotated 0 degrees. Should be pointing up."
+(rotate 0 blue-tri)
+"A solid blue triangle, rotated 30 degrees ccw. Should be flush left"
+(rotate 30 blue-tri)
+"A solid blue triangle, rotated 90 degrees ccw. Should be pointing left."
+(rotate 90 blue-tri)
+"A solid blue triangle, rotated 180 degrees ccw. Should be pointing down."
+(rotate 180 blue-tri)
+"A solid blue triangle, rotated 270 degrees ccw. Should be pointing right."
+(rotate 270 blue-tri)
+"A solid blue triangle, rotated 630 degrees ccw. Should be pointing right."
+(rotate 630 blue-tri)
+"A solid blue triangle, rotated 360 degrees ccw. Should be pointing up."
+(rotate 360 blue-tri)
+"A solid blue triangle, rotated 360.1 degrees ccw. Should be approximately pointing up."
+(rotate 360.1 blue-tri)
+"A solid blue triangle, rotated 720.5 degrees ccw. Should be approximately pointing up."
+(rotate 720.5 blue-tri)
+"A solid blue triangle, rotated 1.5 degrees cw. Should be approximately pointing up."
+(rotate -1.5 blue-tri)
+"A solid blue triangle, rotated -90 degrees ccw (90 cw). Should be pointing right."
+(rotate -90 blue-tri)
+"A solid blue triangle, rotated -450 degrees ccw (450 cw). Should be pointing right."
+(rotate -450 blue-tri)
+"A solid blue triangle, rotated -810 degrees ccw (810 cw). Should be pointing right."
+(rotate -810 blue-tri)
+
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; SCALE & SCALE/XY