From d94765205a591494377adbe7dd53f996589f61bb Mon Sep 17 00:00:00 2001
From: bgk <bgk@a31d4220-a93d-0410-bf67-fe4944624d44>
Date: Sat, 7 Mar 2009 08:23:25 +0000
Subject: [PATCH] Fixed OpenGL display for mesa drivers

---
 src/gtk/screenarea-opengl.cpp | 41 ++++++++++++++++++++++++-----------
 src/gtk/screenarea.cpp        |  2 --
 2 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/src/gtk/screenarea-opengl.cpp b/src/gtk/screenarea-opengl.cpp
index e0128dd9..ee96ecb3 100644
--- a/src/gtk/screenarea-opengl.cpp
+++ b/src/gtk/screenarea-opengl.cpp
@@ -48,15 +48,23 @@ void ScreenAreaGl::on_realize()
 {
   Gtk::DrawingArea::on_realize();
 
-  glMatrixMode(GL_PROJECTION);
-  glLoadIdentity();
+  Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();
+  if (!glwindow->gl_begin(get_gl_context()))
+    return;
 
-  glOrtho(0.0, 1.0, 1.0, 0.0, 0.0, 1.0);
+    glViewport(0, 0, get_width(), get_height());
 
-  glMatrixMode(GL_MODELVIEW);
-  glLoadIdentity();
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
 
-  glClearColor(0.0, 0.0, 0.0, 1.0);
+    glOrtho(0.0, 1.0, 1.0, 0.0, 0.0, 1.0);
+
+    glMatrixMode(GL_MODELVIEW);
+    glLoadIdentity();
+
+    glClearColor(0.0, 0.0, 0.0, 1.0);
+
+  glwindow->gl_end();
 }
 
 void ScreenAreaGl::vDrawPixels(u8 * _puiData)
@@ -77,21 +85,28 @@ void ScreenAreaGl::vDrawBlackScreen()
 
 void ScreenAreaGl::vOnWidgetResize()
 {
-  m_dScaleFactor = min<double>(get_height() / (double)m_iScaledHeight, get_width() / (double)m_iScaledWidth);
-  glViewport(0, 0, get_width(), get_height());
+  Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();
 
-  m_dAreaTop = 1 - m_dScaleFactor * m_iScaledHeight / (double)get_height();
-  m_dAreaLeft = 1 - m_dScaleFactor * m_iScaledWidth / (double)get_width();
+  if (!glwindow->gl_begin(get_gl_context()))
+    return;
+
+    glViewport(0, 0, get_width(), get_height());
+  
+  glwindow->gl_end();
+
+  m_dScaleFactor = min<double>(get_height() / (double)m_iScaledHeight, get_width() / (double)m_iScaledWidth);
+  m_dAreaTop = (1 - m_dScaleFactor * m_iScaledHeight / (double)get_height()) / 2;
+  m_dAreaLeft = (1 - m_dScaleFactor * m_iScaledWidth / (double)get_width()) / 2;
 }
 
 bool ScreenAreaGl::on_expose_event(GdkEventExpose * _pstEvent)
 {
-  Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();
-
-  glRasterPos2f(-1.0f + m_dAreaLeft, 1.0f - m_dAreaTop);
   glPixelZoom(m_dScaleFactor, -m_dScaleFactor);
+  glRasterPos2f(m_dAreaLeft, m_dAreaTop);
+  
   glPixelStorei(GL_UNPACK_ROW_LENGTH, m_iScaledWidth + 1);
 
+  Glib::RefPtr<Gdk::GL::Window> glwindow = get_gl_window();
   if (!glwindow->gl_begin(get_gl_context()))
     return false;
 
diff --git a/src/gtk/screenarea.cpp b/src/gtk/screenarea.cpp
index 04f7eb9d..8148bcfa 100644
--- a/src/gtk/screenarea.cpp
+++ b/src/gtk/screenarea.cpp
@@ -218,8 +218,6 @@ void ScreenArea::vUpdateSize()
   m_iScaledWidth = m_iFilterScale * m_iWidth;
   m_iScaledHeight = m_iFilterScale * m_iHeight;
 
-  vOnWidgetResize();
-
   m_puiPixels = new u32[(m_iScaledWidth + 1) * m_iScaledHeight];
   m_puiDelta = new u8[(m_iWidth + 2) * (m_iHeight + 2) * sizeof(u32)];
   memset(m_puiPixels, 0, (m_iScaledWidth + 1) * m_iScaledHeight * sizeof(u32));