[gtkglarea] examples: replace gluOrtho2D() with glOrtho()

[Javier Jardón <jjardon src gnome org>]

commit 4e52b6c09b19484b472fd0c2bfafb26896f2cd28
Author: Javier Jardón <jjardon gnome org>
Date:   Mon Apr 7 13:54:33 2014 +0100

    examples: replace gluOrtho2D() with glOrtho()

 examples/glpixmap.c       |    3 +--
 examples/gtkglarea_demo.c |    5 ++---
 examples/shaders.c        |    3 +--
 examples/zktor.c          |    3 +--
 4 files changed, 5 insertions(+), 9 deletions(-)
---
diff --git a/examples/glpixmap.c b/examples/glpixmap.c
index 2ac5e50..32cd1b2 100644
--- a/examples/glpixmap.c
+++ b/examples/glpixmap.c
@@ -25,7 +25,6 @@
 #include <windows.h>
 #endif
 #include <GL/gl.h>
-#include <GL/glu.h>
 
 #include <gdk/gdk.h>
 #include <gtkgl/gdkgl.h>
@@ -79,7 +78,7 @@ int main(int argc, char **argv)
   if (gdk_gl_pixmap_make_current(glpixmap, context)) {
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
-    gluOrtho2D(0,100,100,0);
+    glOrtho(0,100,100,0,-1,1);
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
 
diff --git a/examples/gtkglarea_demo.c b/examples/gtkglarea_demo.c
index ace4604..377aafb 100644
--- a/examples/gtkglarea_demo.c
+++ b/examples/gtkglarea_demo.c
@@ -32,7 +32,7 @@
  *
  * Compile command:
  *
- * gcc gtkglarea_demo.c `gtk-config --libs --cflags` -lMesaGL -lMesaGLU -lgtkgl
+ * gcc gtkglarea_demo.c `gtk-config --libs --cflags` -lMesaGL -lgtkgl
  *
  ************/
 
@@ -43,7 +43,6 @@
 #endif
 
 #include <GL/gl.h>
-#include <GL/glu.h>
 #include <gtk/gtk.h>
 #include <gtkgl/gtkglarea.h>
 
@@ -375,7 +374,7 @@ gint glarea_reshape (GtkWidget* widget, GdkEventConfigure* event) {
     glViewport (0, 0, w, h);
     glMatrixMode (GL_PROJECTION);
     glLoadIdentity ();
-    gluOrtho2D (-(w>>1), (w>>1), -(h>>1), h>>1);
+    glOrtho (-(w>>1), (w>>1), -(h>>1), h>>1, -1, 1);
     glMatrixMode (GL_MODELVIEW);
 
   }
diff --git a/examples/shaders.c b/examples/shaders.c
index 7b0169f..814c10b 100644
--- a/examples/shaders.c
+++ b/examples/shaders.c
@@ -30,7 +30,6 @@
 #endif
 
 #include <GL/gl.h>
-#include <GL/glu.h>
 #include <gtk/gtk.h>
 #include <gtkgl/gtkglarea.h>
 
@@ -333,7 +332,7 @@ gint glarea_reshape (GtkWidget* widget, GdkEventConfigure* event) {
     glViewport (0, 0, w, h);
     glMatrixMode (GL_PROJECTION);
     glLoadIdentity ();
-    gluOrtho2D (-(w>>1), (w>>1), -(h>>1), h>>1);
+    glOrtho (-(w>>1), (w>>1), -(h>>1), h>>1, -1, 1);
     glMatrixMode (GL_MODELVIEW);
 
   }
diff --git a/examples/zktor.c b/examples/zktor.c
index 4f7c8c1..ac34918 100644
--- a/examples/zktor.c
+++ b/examples/zktor.c
@@ -30,7 +30,6 @@
 #include <gdk/gdkkeysyms.h>
 #include <gtkgl/gtkglarea.h>
 #include <GL/gl.h>
-#include <GL/glu.h>
 
 #ifndef M_PI
 #define M_PI 3.14
@@ -509,7 +508,7 @@ void game_render()
   /* view */
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
-  gluOrtho2D(-115,115,-115,115);
+  glOrtho(-115,115,-115,115,-1,1);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();