From 673e8c67237f1399f97ef1773cfeb01035f728b9 Mon Sep 17 00:00:00 2001
From: Rogier <rogier777@gmail.com>
Date: Sun, 7 Jun 2015 21:30:45 +0200
Subject: [PATCH] When using transparency, don't compute new value when pixel
 is already fully opaque

This makes the code slightly more efficient, and should not affect the
generated map at all.
---
 PixelAttributes.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/PixelAttributes.cpp b/PixelAttributes.cpp
index 12a5d1a..fa82bbb 100644
--- a/PixelAttributes.cpp
+++ b/PixelAttributes.cpp
@@ -259,6 +259,8 @@ void PixelAttribute::mixUnder(const PixelAttribute &p)
 		}
 		m_h = p.m_h;
 	}
+	else if (m_a == 1)
+		;		// Nothing to do: pixel is already fully opaque.
 	else if ((m_mixMode & AlphaMixCumulative) == AlphaMixCumulative || (m_mixMode == AlphaMixAverage && p.m_a == 1)) {
 		PixelAttribute pp(p);
 #ifdef DEBUG