#1559 - Adds hs.image:colorAt(point)

extensions/image/internal.m

@@ -1272,6 +1272,31 @@ static int getImageSize(lua_State* L) {
     return 1 ;
 }
 
+/// hs.image:colorAt(point) -> table
+/// Method
+/// Reads the color of the pixel at the specified location.
+///
+/// Parameters:
+///  * `point` - a `hs.geometry.point`
+///
+/// Returns:
+///  * A `hs.drawing.color` object
+static int colorAt(lua_State* L) {
+    LuaSkin *skin = [LuaSkin shared] ;
+    [skin checkArgs:LS_TUSERDATA, USERDATA_TAG, LS_TTABLE, LS_TBREAK] ;
+    NSImage *theImage = [skin luaObjectAtIndex:1 toClass:"NSImage"] ;
+
+    NSPoint point  = [skin tableToPointAtIndex:2] ;
+
+	// Source: https://stackoverflow.com/a/48400410
+    [theImage lockFocus];
+	NSColor *pixelColor = NSReadPixel(point);
+	[theImage unlockFocus];
+
+    [skin pushNSObject:pixelColor];
+    return 1;
+}
+
 /// hs.image:croppedCopy(rectangle) -> object
 /// Method
 /// Returns a copy of the portion of the image specified by the rectangle specified.
@@ -1624,6 +1649,7 @@ static int userdata_gc(lua_State* L) {
     {"croppedCopy",       croppedCopy},
     {"saveToFile",        saveToFile},
     {"encodeAsURLString", encodeAsString},
+    {"colorAt",			  colorAt},
 
     {"__tostring",        userdata_tostring},
     {"__eq",              userdata_eq},