From 085463c8732951078299c4b46c4c96bf60b70a7e Mon Sep 17 00:00:00 2001
From: kiritow <1362050620@qq.com>
Date: Wed, 12 Apr 2017 09:22:15 +0800
Subject: [PATCH] Add BlendMode caster

---
 MiniEngine.cpp | 58 ++++++++++++++++++++++++++++++++++++++++++++++----
 MiniEngine.h   | 20 +++++------------
 2 files changed, 59 insertions(+), 19 deletions(-)

diff --git a/MiniEngine.cpp b/MiniEngine.cpp
index 85b3d4e..739cdb3 100644
--- a/MiniEngine.cpp
+++ b/MiniEngine.cpp
@@ -17,6 +17,41 @@
 
 namespace MiniEngine
 {
+    namespace _internal
+    {
+        BlendMode getBlendModeFromSDLBlendMode(SDL_BlendMode mode)
+        {
+            switch(mode)
+            {
+            case SDL_BLENDMODE_ADD:
+                return BlendMode::Add;
+            case SDL_BLENDMODE_BLEND:
+                return BlendMode::Blend;
+            case SDL_BLENDMODE_MOD:
+                return BlendMode::Mod;
+            case SDL_BLENDMODE_NONE:
+            default:/// return BlendMode::None on default.
+                return BlendMode::None;
+            }
+        }
+
+        SDL_BlendMode getSDLBlendModeFromBlendMode(BlendMode mode)
+        {
+            switch(mode)
+            {
+            case BlendMode::Add:
+                return SDL_BLENDMODE_ADD;
+            case BlendMode::Blend:
+                return SDL_BLENDMODE_BLEND;
+            case BlendMode::Mod:
+                return SDL_BLENDMODE_MOD;
+            case BlendMode::None:
+            default:/// return SDL_BLENDMODE_NONE on default.
+                return SDL_BLENDMODE_NONE;
+            }
+        }
+    }/// End of namespace _internal
+
 	Rect::Rect(int X, int Y, int W, int H)
 	{
 		x = X;
@@ -213,6 +248,19 @@ namespace MiniEngine
         }
     }
 
+    BlendMode Surface::getBlendMode()
+    {
+        SDL_BlendMode temp;
+        /// FIXME: return value are ignored.
+        SDL_GetSurfaceBlendMode(_get(),&temp);
+        return _internal::getBlendModeFromSDLBlendMode(temp);
+    }
+
+    int Surface::setBlendMode(BlendMode mode)
+    {
+        return SDL_SetSurfaceBlendMode(_get(),_internal::getSDLBlendModeFromBlendMode(mode));
+    }
+
     int Surface::savePNG(const std::string& filename)
     {
         return IMG_SavePNG(_get(),filename.c_str());
@@ -262,14 +310,14 @@ namespace MiniEngine
 
 	int Texture::setBlendMode(BlendMode mode)
 	{
-		return SDL_SetTextureBlendMode(_get(), static_cast<SDL_BlendMode>(mode));
+		return SDL_SetTextureBlendMode(_get(), _internal::getSDLBlendModeFromBlendMode(mode));
 	}
 
 	BlendMode Texture::getBlendMode()
 	{
 		SDL_BlendMode temp;
 		SDL_GetTextureBlendMode(_get(), &temp);
-		return static_cast<BlendMode>(temp);
+		return _internal::getBlendModeFromSDLBlendMode(temp);
 	}
 
 	/// Alpha:  0: Transparent 255: opaque
@@ -356,16 +404,18 @@ namespace MiniEngine
 
 	int Renderer::setBlendMode(BlendMode mode)
 	{
-		return SDL_SetRenderDrawBlendMode(_get(), static_cast<SDL_BlendMode>(mode));
+		return SDL_SetRenderDrawBlendMode(_get(), _internal::getSDLBlendModeFromBlendMode(mode));
 	}
 
 	BlendMode Renderer::getBlendMode()
 	{
 		SDL_BlendMode temp;
 		SDL_GetRenderDrawBlendMode(_get(), &temp);
-		return static_cast<BlendMode>(temp);
+		return _internal::getBlendModeFromSDLBlendMode(temp);
 	}
 
+
+
 	int Renderer::setTarget(Texture & t)
 	{
 		return SDL_SetRenderTarget(_get(), t._get());
diff --git a/MiniEngine.h b/MiniEngine.h
index 65e5c88..4c2ed00 100644
--- a/MiniEngine.h
+++ b/MiniEngine.h
@@ -89,13 +89,7 @@ namespace MiniEngine
         friend class Renderer;
 	};
 
-	enum class BlendMode
-	{
-		None = SDL_BLENDMODE_NONE,
-		Blend = SDL_BLENDMODE_BLEND,
-		Add = SDL_BLENDMODE_ADD,
-		Mod = SDL_BLENDMODE_MOD
-	};
+	enum class BlendMode { None,Blend,Add,Mod };
 
 	class Surface
 	{
@@ -104,6 +98,8 @@ namespace MiniEngine
         int savePNG(const std::string& filename);
         int getw();
         int geth();
+        BlendMode getBlendMode();
+        int setBlendMode(BlendMode mode);
 	protected:
 		Surface() = default;
 	private:
@@ -150,13 +146,7 @@ namespace MiniEngine
 		friend class Renderer;
 	};
 
-	enum class RendererType
-	{
-		Software,
-		Accelerated,
-		PresentSync,
-		TargetTexture
-	};
+	enum class RendererType { Software, Accelerated, PresentSync, TargetTexture };
 
 	enum class FlipMode { None, Horizontal, Vertical };
 
@@ -204,7 +194,7 @@ namespace MiniEngine
 		friend class Window;
 	};
 
-	enum class MessageBoxType { Error,Warning,Information };
+	enum class MessageBoxType { Error, Warning, Information };
 
 	class Window
 	{