From 79465895afafff520c7d6708653ac810916cb309 Mon Sep 17 00:00:00 2001
From: Luke Page <luke.a.page@gmail.com>
Date: Thu, 6 Aug 2015 18:50:36 +0100
Subject: [PATCH] Gamma division constant

---
 lib/constants.js | 4 +++-
 lib/packer.js    | 2 +-
 lib/parser.js    | 2 +-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/lib/constants.js b/lib/constants.js
index 7d52443..96af8eb 100755
--- a/lib/constants.js
+++ b/lib/constants.js
@@ -14,5 +14,7 @@ module.exports = {
 
   COLOR_PALETTE: 1,
   COLOR_COLOR: 2,
-  COLOR_ALPHA: 4
+  COLOR_ALPHA: 4,
+
+  GAMMA_DIVISION: 100000
 };
diff --git a/lib/packer.js b/lib/packer.js
index 325c83d..0960523 100755
--- a/lib/packer.js
+++ b/lib/packer.js
@@ -76,7 +76,7 @@ Packer.prototype._packChunk = function(type, data) {
 
 Packer.prototype._packGAMA = function(gamma) {
   var buf = new Buffer(4);
-  buf.writeUInt32BE(Math.floor(gamma * 100000), 0); // TODO constant
+  buf.writeUInt32BE(Math.floor(gamma * constants.GAMMA_DIVISION), 0);
   return this._packChunk(constants.TYPE_gAMA, buf);
 };
 
diff --git a/lib/parser.js b/lib/parser.js
index 500f05f..2eddfaf 100644
--- a/lib/parser.js
+++ b/lib/parser.js
@@ -249,7 +249,7 @@ Parser.prototype._handleGAMA = function(length) {
 Parser.prototype._parseGAMA = function(data) {
 
   this._crc.write(data);
-  this.gamma(data.readUInt32BE(0) / 100000); //TODO constant
+  this.gamma(data.readUInt32BE(0) / constants.GAMMA_DIVISION);
 
   this._handleChunkEnd();
 };