From b46be04fc6659e5df787359b5dfbffbe2e2ffac7 Mon Sep 17 00:00:00 2001
From: Kangning Li <likangning93@gmail.com>
Date: Thu, 7 Jun 2018 15:00:21 -0400
Subject: [PATCH] load greyscale images as luminance instead of alpha

---
 lib/loadImage.js           | 2 +-
 specs/lib/loadImageSpec.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/loadImage.js b/lib/loadImage.js
index c238a27..b9b4fda 100644
--- a/lib/loadImage.js
+++ b/lib/loadImage.js
@@ -96,7 +96,7 @@ function getChannels(colorType) {
 function getFormat(channels) {
     switch (channels) {
         case 1:
-            return WebGLConstants.ALPHA;
+            return WebGLConstants.LUMINANCE;
         case 2:
             return WebGLConstants.LUMINANCE_ALPHA;
         case 3:
diff --git a/specs/lib/loadImageSpec.js b/specs/lib/loadImageSpec.js
index 3554d83..8a5dccc 100644
--- a/specs/lib/loadImageSpec.js
+++ b/specs/lib/loadImageSpec.js
@@ -60,7 +60,7 @@ describe('loadImage', function() {
         expect(loadImage(grayscaleImage, defaultOptions)
             .then(function(info) {
                 expect(info.transparent).toBe(false);
-                expect(info.format).toBe(WebGLConstants.ALPHA);
+                expect(info.format).toBe(WebGLConstants.LUMINANCE);
                 expect(info.source).toBeDefined();
                 expect(info.extension).toBe('.png');
             }), done).toResolve();