From 773036a3bac081935a66f74150a78d3823823801 Mon Sep 17 00:00:00 2001
From: Ryan Oldenburg <guzba8@gmail.com>
Date: Thu, 21 Jan 2021 19:07:07 -0600
Subject: [PATCH] add -d:useStb

---
 src/pixie/fileformats/jpg.nim | 20 +++++++++++++-------
 tests/test_jpg.nim            |  9 +++++----
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/src/pixie/fileformats/jpg.nim b/src/pixie/fileformats/jpg.nim
index 3b3de9b..287ab89 100644
--- a/src/pixie/fileformats/jpg.nim
+++ b/src/pixie/fileformats/jpg.nim
@@ -1,17 +1,23 @@
-import pixie/images, pixie/common, pixie/fileformats/stb_image/stb_image
+import pixie/images, pixie/common
+
+when defined(useStb):
+  import pixie/fileformats/stb_image/stb_image
 
 const
   jpgStartOfImage* = [0xFF.uint8, 0xD8]
 
 proc decodeJpg*(data: seq[uint8]): Image =
   ## Decodes the JPEG into an Image.
-  var
-    width: int
-    height: int
-  let pixels = loadFromMemory(data, width, height)
+  when not defined(useStb):
+    raise newException(PixieError, "Decoding JPG requires -d:useStb")
+  else:
+    var
+      width: int
+      height: int
+    let pixels = loadFromMemory(data, width, height)
 
-  result = newImage(width, height)
-  copyMem(result.data[0].addr, pixels[0].unsafeAddr, pixels.len)
+    result = newImage(width, height)
+    copyMem(result.data[0].addr, pixels[0].unsafeAddr, pixels.len)
 
 proc decodeJpg*(data: string): Image {.inline.} =
   decodeJpg(cast[seq[uint8]](data))
diff --git a/tests/test_jpg.nim b/tests/test_jpg.nim
index 35f56b0..b495c9a 100644
--- a/tests/test_jpg.nim
+++ b/tests/test_jpg.nim
@@ -1,5 +1,6 @@
-import pixie/fileformats/jpg
+when defined(useStb):
+  import pixie/fileformats/jpg
 
-let
-  original = readFile("tests/images/jpg/jpeg420exif.jpg")
-  stbDecoded = decodeJpg(original)
+  let
+    original = readFile("tests/images/jpg/jpeg420exif.jpg")
+    stbDecoded = decodeJpg(original)