From ab98b0de45f7e5e93551117b4f16e54e54c42a9c Mon Sep 17 00:00:00 2001
From: Alexander Szpakowski <amaranth72@gmail.com>
Date: Tue, 1 Jan 2013 21:44:27 -0400
Subject: [PATCH] Added mipmap support to Image filter struct and OpenGL
 texture filter helper functions

---
 src/modules/graphics/Image.cpp         |  1 +
 src/modules/graphics/Image.h           |  2 ++
 src/modules/graphics/opengl/OpenGL.cpp | 43 +++++++++++++++++++++-----
 3 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/src/modules/graphics/Image.cpp b/src/modules/graphics/Image.cpp
index 1e2b093be..c985cd482 100644
--- a/src/modules/graphics/Image.cpp
+++ b/src/modules/graphics/Image.cpp
@@ -30,6 +30,7 @@ Image::Filter Image::defaultFilter;
 Image::Filter::Filter()
 	: min(FILTER_LINEAR)
 	, mag(FILTER_LINEAR)
+	, mipmap(FILTER_NONE)
 {
 }
 
diff --git a/src/modules/graphics/Image.h b/src/modules/graphics/Image.h
index 85ef7f55d..881ae94fc 100644
--- a/src/modules/graphics/Image.h
+++ b/src/modules/graphics/Image.h
@@ -46,6 +46,7 @@ public:
 	{
 		FILTER_LINEAR = 1,
 		FILTER_NEAREST,
+		FILTER_NONE,
 		FILTER_MAX_ENUM
 	};
 
@@ -54,6 +55,7 @@ public:
 		Filter();
 		FilterMode min;
 		FilterMode mag;
+		FilterMode mipmap;
 	};
 
 	struct Wrap
diff --git a/src/modules/graphics/opengl/OpenGL.cpp b/src/modules/graphics/opengl/OpenGL.cpp
index b1292b1d7..4cae16000 100644
--- a/src/modules/graphics/opengl/OpenGL.cpp
+++ b/src/modules/graphics/opengl/OpenGL.cpp
@@ -56,16 +56,27 @@ void setTextureFilter(const graphics::Image::Filter &f)
 {
 	GLint gmin, gmag;
 	
-	switch (f.min)
+	if (f.mipmap == Image::FILTER_NONE)
 	{
-	case Image::FILTER_NEAREST:
-		gmin = GL_NEAREST;
-		break;
-	case Image::FILTER_LINEAR:
-	default:
-		gmin = GL_LINEAR;
-		break;
+		if (f.min == Image::FILTER_NEAREST)
+			gmin = GL_NEAREST;
+		else // f.min == Image::FILTER_LINEAR
+			gmin = GL_LINEAR;
 	}
+	else
+	{
+		if (f.min == f.mipmap == Image::FILTER_NEAREST)
+			gmin = GL_NEAREST_MIPMAP_NEAREST;
+		else if (f.min == Image::FILTER_NEAREST && f.mipmap == Image::FILTER_LINEAR)
+			gmin = GL_NEAREST_MIPMAP_LINEAR;
+		else if (f.min == Image::FILTER_LINEAR && f.mipmap == Image::FILTER_NEAREST)
+			gmin = GL_LINEAR_MIPMAP_NEAREST;
+		else if (f.min == f.mipmap == Image::FILTER_LINEAR)
+			gmin = GL_LINEAR_MIPMAP_LINEAR;
+		else
+			gmin = GL_LINEAR;
+	}
+	
 	
 	switch (f.mag)
 	{
@@ -94,10 +105,26 @@ graphics::Image::Filter getTextureFilter()
 	{
 	case GL_NEAREST:
 		f.min = Image::FILTER_NEAREST;
+		f.mipmap = Image::FILTER_NONE;
+		break;
+	case GL_NEAREST_MIPMAP_NEAREST:
+		f.min = f.mipmap = Image::FILTER_NEAREST;
+		break;
+	case GL_NEAREST_MIPMAP_LINEAR:
+		f.min = Image::FILTER_NEAREST;
+		f.mipmap = Image::FILTER_LINEAR;
+		break;
+	case GL_LINEAR_MIPMAP_NEAREST:
+		f.min = Image::FILTER_LINEAR;
+		f.mipmap = Image::FILTER_NEAREST;
+		break;
+	case GL_LINEAR_MIPMAP_LINEAR:
+		f.min = f.mipmap = Image::FILTER_LINEAR;
 		break;
 	case GL_LINEAR:
 	default:
 		f.min = Image::FILTER_LINEAR;
+		f.mipmap = Image::FILTER_NONE;
 		break;
 	}