From 51eede9ca3ab1d535fc376c29604f971e5d38880 Mon Sep 17 00:00:00 2001
From: Nicolas Capens <capn@google.com>
Date: Wed, 25 Mar 2015 14:03:21 -0400
Subject: [PATCH] Implement EGL_SWAP_BEHAVIOR for eglSurfaceAttrib().

SwiftShader currently always preserves the color buffer on eglSwapBuffers,
so both EGL_BUFFER_PRESERVED and EGL_BUFFER_DESTROYED can be used without
real changes.

Change-Id: I55fcd7d4b4211483d8876c15d3d6ea77ea2685e6
Reviewed-on: https://swiftshader-review.googlesource.com/2721
Reviewed-by: Ping-Hao Wu <pinghao@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
Tested-by: Nicolas Capens <capn@google.com>
---
 src/OpenGL/libEGL/Surface.cpp | 20 +++++++++++++++-----
 src/OpenGL/libEGL/Surface.h   |  5 ++++-
 src/OpenGL/libEGL/libEGL.cpp  | 20 +++++++++++++++++++-
 3 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/src/OpenGL/libEGL/Surface.cpp b/src/OpenGL/libEGL/Surface.cpp
index 7d9998887..466f10f50 100644
--- a/src/OpenGL/libEGL/Surface.cpp
+++ b/src/OpenGL/libEGL/Surface.cpp
@@ -208,6 +208,11 @@ egl::Image *Surface::getDepthStencil()
     return mDepthStencil;
 }
 
+void Surface::setSwapBehavior(EGLenum swapBehavior)
+{
+	mSwapBehavior = swapBehavior;
+}
+
 void Surface::setSwapInterval(EGLint interval)
 {
     if(mSwapInterval == interval)
@@ -225,6 +230,16 @@ EGLint Surface::getConfigID() const
     return mConfig->mConfigID;
 }
 
+EGLenum Surface::getSurfaceType() const
+{
+    return mConfig->mSurfaceType;
+}
+
+sw::Format Surface::getInternalFormat() const
+{
+    return mConfig->mRenderTargetFormat;
+}
+
 EGLint Surface::getWidth() const
 {
     return mWidth;
@@ -270,11 +285,6 @@ egl::Texture *Surface::getBoundTexture() const
     return mTexture;
 }
 
-sw::Format Surface::getInternalFormat() const
-{
-    return mConfig->mRenderTargetFormat;
-}
-
 bool Surface::checkForResize()
 {
     #if defined(_WIN32)
diff --git a/src/OpenGL/libEGL/Surface.h b/src/OpenGL/libEGL/Surface.h
index 55cbed351..1db6fc1a4 100644
--- a/src/OpenGL/libEGL/Surface.h
+++ b/src/OpenGL/libEGL/Surface.h
@@ -44,9 +44,13 @@ public:
     virtual egl::Image *getRenderTarget();
     virtual egl::Image *getDepthStencil();
 
+	void setSwapBehavior(EGLenum swapBehavior);
     void setSwapInterval(EGLint interval);
 
     virtual EGLint getConfigID() const;
+	virtual EGLenum getSurfaceType() const;
+	virtual sw::Format getInternalFormat() const;
+
     virtual EGLint getWidth() const;
     virtual EGLint getHeight() const;
     virtual EGLint getPixelAspectRatio() const;
@@ -54,7 +58,6 @@ public:
     virtual EGLenum getSwapBehavior() const;
     virtual EGLenum getTextureFormat() const;
     virtual EGLenum getTextureTarget() const;
-    virtual sw::Format getInternalFormat() const;
 
     virtual void setBoundTexture(egl::Texture *texture);
     virtual egl::Texture *getBoundTexture() const;
diff --git a/src/OpenGL/libEGL/libEGL.cpp b/src/OpenGL/libEGL/libEGL.cpp
index 3a3dce9d7..e0163908f 100644
--- a/src/OpenGL/libEGL/libEGL.cpp
+++ b/src/OpenGL/libEGL/libEGL.cpp
@@ -479,7 +479,25 @@ EGLBoolean EGLAPIENTRY eglSurfaceAttrib(EGLDisplay dpy, EGLSurface surface, EGLi
 		return EGL_FALSE;
 	}
 
-	UNIMPLEMENTED();   // FIXME
+	switch(attribute)
+	{
+	case EGL_SWAP_BEHAVIOR:
+		if(value == EGL_BUFFER_PRESERVED)
+		{
+			if(!(eglSurface->getSurfaceType() && EGL_SWAP_BEHAVIOR_PRESERVED_BIT))
+			{
+				return error(EGL_BAD_MATCH, EGL_FALSE);
+			}
+		}
+		else if(value != EGL_BUFFER_DESTROYED)
+		{
+			return error(EGL_BAD_PARAMETER, EGL_FALSE);
+		}
+		eglSurface->setSwapBehavior(value);
+		break;
+	default:
+		UNIMPLEMENTED();   // FIXME
+	}
 
 	return success(EGL_TRUE);
 }
-- 
2.11.0