From 6a91e40ef5891aa16b044e52150eb177f928175c Mon Sep 17 00:00:00 2001
From: Mikael Finstad <finstaden@gmail.com>
Date: Thu, 30 Apr 2020 22:31:59 +0800
Subject: [PATCH] check for GL #29

---
 glTransitions.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/glTransitions.js b/glTransitions.js
index 26b3fe7..a026ad2 100644
--- a/glTransitions.js
+++ b/glTransitions.js
@@ -8,6 +8,10 @@ const createTexture = require('gl-texture2d');
 module.exports = ({ width, height, channels }) => {
   const gl = GL(width, height);
 
+  if (!gl) {
+    throw new Error('gl returned null, this probably means that some dependencies are not installed. See README.');
+  }
+
   function runTransitionOnFrame({ fromFrame, toFrame, progress, transitionName, transitionParams = {} }) {
     function convertFrame(buf) {
       // @see https://github.com/stackgl/gl-texture2d/issues/16