From c37dcd4a568ee20b058c6a793298eaca19d851ee Mon Sep 17 00:00:00 2001
From: Ryan Oldenburg <guzba8@gmail.com>
Date: Wed, 27 Jan 2021 17:13:30 -0600
Subject: [PATCH] dont mutate shadow mask param

---
 src/pixie/images.nim | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/pixie/images.nim b/src/pixie/images.nim
index a751dd0..e8b0667 100644
--- a/src/pixie/images.nim
+++ b/src/pixie/images.nim
@@ -547,12 +547,13 @@ proc shadow*(
   mask: Image, offset: Vec2, spread, blur: float32, color: ColorRGBA
 ): Image =
   ## Create a shadow of the image with the offset, spread and blur.
+  let copy = mask.copy()
   if offset != vec2(0, 0):
-    mask.shift(offset)
+    copy.shift(offset)
   if spread > 0:
-    mask.spread(spread)
+    copy.spread(spread)
   if blur > 0:
-    mask.blurAlpha(blur)
+    copy.blurAlpha(blur)
   result = newImage(mask.width, mask.height)
   result.fill(color)
-  result.draw(mask, blendMode = bmMask)
+  result.draw(copy, blendMode = bmMask)