From dc52950aa161aacf564b96abb8af6056dfa650cd Mon Sep 17 00:00:00 2001
From: Oleg Romashin <romaxa@gmail.com>
Date: Wed, 23 Jun 2010 05:24:22 -0400
Subject: [PATCH] Bug 560537 - Make EGL provider use GL context created by Qt.
 r=bas.schouten.

--HG--
extra : rebase_source : 45a0da770a8e8a89c4ca02c67469893cd4f9872a
---
 gfx/thebes/public/GLDefs.h              |  2 +
 gfx/thebes/src/GLContextProviderEGL.cpp | 53 +++++++++++++++++++++++--
 2 files changed, 51 insertions(+), 4 deletions(-)

diff --git a/gfx/thebes/public/GLDefs.h b/gfx/thebes/public/GLDefs.h
index e0fa9a468e00..35602f70993b 100644
--- a/gfx/thebes/public/GLDefs.h
+++ b/gfx/thebes/public/GLDefs.h
@@ -57,7 +57,9 @@ typedef unsigned char GLubyte;
 typedef unsigned short GLushort;
 typedef float GLfloat;
 typedef float GLclampf;
+#ifndef GLdouble_defined
 typedef double GLdouble;
+#endif
 typedef double GLclampd;
 typedef void GLvoid;
 
diff --git a/gfx/thebes/src/GLContextProviderEGL.cpp b/gfx/thebes/src/GLContextProviderEGL.cpp
index 47a35e4a3951..a95a7bddc464 100644
--- a/gfx/thebes/src/GLContextProviderEGL.cpp
+++ b/gfx/thebes/src/GLContextProviderEGL.cpp
@@ -47,6 +47,8 @@
 #define GET_NATIVE_WINDOW(aWidget) (EGLNativeWindowType)GDK_WINDOW_XID((GdkWindow *) aWidget->GetNativeData(NS_NATIVE_WINDOW))
 #elif defined(MOZ_WIDGET_QT)
 #include <QWidget>
+#include <QtOpenGL/QGLWidget>
+#define GLdouble_defined 1
 // we're using default display for now
 #define GET_NATIVE_WINDOW(aWidget) (EGLNativeWindowType)static_cast<QWidget*>(aWidget->GetNativeData(NS_NATIVE_SHELLWIDGET))->handle()
 #endif
@@ -197,12 +199,21 @@ class GLContextEGL : public GLContext
 {
 public:
     GLContextEGL(EGLDisplay aDisplay, EGLConfig aConfig,
-                 EGLSurface aSurface, EGLContext aContext)
-        : mDisplay(aDisplay), mConfig(aConfig),
-          mSurface(aSurface), mContext(aContext){}
+                 EGLSurface aSurface, EGLContext aContext,
+                 void *aGLWidget = nsnull)
+        : mDisplay(aDisplay), mConfig(aConfig) 
+        , mSurface(aSurface), mContext(aContext)
+        , mGLWidget(aGLWidget)
+    {}
 
     ~GLContextEGL()
     {
+        // If mGLWidget is non-null, then we've been given it by the GL context provider,
+        // and it's managed by the widget implementation. In this case, We can't destroy
+        // our contexts.
+        if (mGLWidget)
+            return;
+
         sEGLLibrary.fDestroyContext(mDisplay, mContext);
         sEGLLibrary.fDestroySurface(mDisplay, mSurface);
     }
@@ -226,7 +237,15 @@ class GLContextEGL : public GLContext
         // where MakeCurrent with an already-current context is
         // still expensive.
         if (sEGLLibrary.fGetCurrentContext() != mContext) {
-            succeeded = sEGLLibrary.fMakeCurrent(mDisplay, mSurface, mSurface, mContext);
+            if (mGLWidget) {
+#ifdef MOZ_WIDGET_QT
+                static_cast<QGLWidget*>(mGLWidget)->makeCurrent();
+#else
+                succeeded = PR_FALSE;
+#endif
+            }
+            else
+                succeeded = sEGLLibrary.fMakeCurrent(mDisplay, mSurface, mSurface, mContext);
             NS_ASSERTION(succeeded, "Failed to make GL context current!");
         }
 
@@ -258,6 +277,7 @@ class GLContextEGL : public GLContext
     EGLConfig  mConfig;
     EGLSurface mSurface;
     EGLContext mContext;
+    void      *mGLWidget;
 };
 
 already_AddRefed<GLContext>
@@ -267,6 +287,31 @@ GLContextProvider::CreateForWindow(nsIWidget *aWidget)
         return nsnull;
     }
 
+#ifdef MOZ_WIDGET_QT
+    QWidget *viewport = static_cast<QWidget*>(aWidget->GetNativeData(NS_NATIVE_SHELLWIDGET));
+    if (!viewport)
+        return nsnull;
+
+    if (viewport->paintEngine()->type() == QPaintEngine::OpenGL2) {
+        // Qt widget viewport already have GL context created by Qt
+        // Create dummy GLContextEGL class
+        nsRefPtr<GLContextEGL> glContext =
+            new GLContextEGL(NULL, NULL, NULL,
+                             sEGLLibrary.fGetCurrentContext(),
+                             viewport);
+        if (!glContext->Init())
+            return nsnull;
+        return glContext.forget().get();
+    } else {
+        // All Qt nsIWidget's have the same X-Window surface
+        // And EGL not allowing to create multiple GL context for the same window
+        // we should be able to create GL context for QGV viewport once, and reuse it for all child widgets
+        NS_WARNING("Need special GLContext implementation for QT widgets structure");
+        // Switch to software rendering here
+        return nsnull;
+    }
+#endif
+
     EGLDisplay display;
     EGLConfig  config;
     EGLSurface surface;