From d654fb7dd6f73bc34acf3df750435bc09a69496f Mon Sep 17 00:00:00 2001
From: Jonas Kulla <Nyocurio@gmail.com>
Date: Tue, 12 Aug 2014 21:28:18 +0200
Subject: [PATCH] Add internal 'KeepDestAlpha' BlendType (for use in WindowVX)
---
src/etc.h | 2 ++
src/glstate.cpp | 6 ++++++
2 files changed, 8 insertions(+)
diff --git a/src/etc.h b/src/etc.h
index 202dd9d..3e17acf 100644
--- a/src/etc.h
+++ b/src/etc.h
@@ -31,6 +31,8 @@ struct SDL_Color;
enum BlendType
{
+ BlendKeepDestAlpha = -1,
+
BlendNormal = 0,
BlendAddition = 1,
BlendSubstraction = 2
diff --git a/src/glstate.cpp b/src/glstate.cpp
index 613b55e..8c3a2a4 100644
--- a/src/glstate.cpp
+++ b/src/glstate.cpp
@@ -64,6 +64,12 @@ void GLBlendMode::apply(const BlendType &value)
{
switch (value)
{
+ case BlendKeepDestAlpha :
+ gl.BlendEquation(GL_FUNC_ADD);
+ gl.BlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA,
+ GL_ZERO, GL_ONE);
+ break;
+
case BlendNormal :
gl.BlendEquation(GL_FUNC_ADD);
gl.BlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA,