From 03d75816a082e87a7161bf45fb1a4e8ffa1c0424 Mon Sep 17 00:00:00 2001
From: Will Norris <will@willnorris.com>
Date: Wed, 6 Sep 2017 22:01:13 +0000
Subject: [PATCH] fix ordering of flip and rotation transformations

Fixes #112
---
 transform.go      | 16 ++++++++--------
 transform_test.go |  7 ++++++-
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/transform.go b/transform.go
index cfa00bf..92e0d82 100644
--- a/transform.go
+++ b/transform.go
@@ -207,14 +207,6 @@ func transformImage(m image.Image, opt Options) image.Image {
 		}
 	}
 
-	// flip
-	if opt.FlipVertical {
-		m = imaging.FlipV(m)
-	}
-	if opt.FlipHorizontal {
-		m = imaging.FlipH(m)
-	}
-
 	// rotate
 	switch opt.Rotate {
 	case 90:
@@ -225,5 +217,13 @@ func transformImage(m image.Image, opt Options) image.Image {
 		m = imaging.Rotate270(m)
 	}
 
+	// flip
+	if opt.FlipVertical {
+		m = imaging.FlipV(m)
+	}
+	if opt.FlipHorizontal {
+		m = imaging.FlipH(m)
+	}
+
 	return m
 }
diff --git a/transform_test.go b/transform_test.go
index 7fc0e5c..2897bbc 100644
--- a/transform_test.go
+++ b/transform_test.go
@@ -185,6 +185,11 @@ func TestTransformImage(t *testing.T) {
 			Options{FlipHorizontal: true, FlipVertical: true},
 			newImage(2, 2, yellow, blue, green, red),
 		},
+		{
+			ref,
+			Options{Rotate: 90, FlipHorizontal: true},
+			newImage(2, 2, yellow, green, blue, red),
+		},
 
 		// resizing
 		{ // can't resize larger than original image
@@ -247,7 +252,7 @@ func TestTransformImage(t *testing.T) {
 		{
 			newImage(4, 2, red, red, blue, blue, red, red, blue, blue),
 			Options{Width: 2, Height: 1, Fit: true, FlipHorizontal: true, Rotate: 90},
-			newImage(1, 2, red, blue),
+			newImage(1, 2, blue, red),
 		},
 
 		// crop