2 files changed, 147 insertions, 12 deletions

diff --git a/src/Gui/RenderArea.cpp b/src/Gui/RenderArea.cpp
index c19c0a5..ec37f67 100644
--- a/src/Gui/RenderArea.cpp
+++ b/src/Gui/RenderArea.cpp
@@ -1,6 +1,8 @@
 #include "RenderArea.h"
 #include <iostream>
 #include <cstdlib>
+#include <cmath>
+#include <gtkmm/toolbutton.h>
 #include <GL/gl.h>
 
 namespace ZoomEdit {
@@ -9,7 +11,7 @@ namespace Gui {
 GdkGLConfig *RenderArea::glconfig = NULL;
 
 RenderArea::RenderArea(BaseObjectType *cobject, const Glib::RefPtr<Gnome::Glade::Xml> &xml)
-: Gtk::DrawingArea(cobject) {
+: Gtk::DrawingArea(cobject), zoomLevel(0), scale(100), x(0), y(0) {
   if(!glconfig) {
     glconfig = gdk_gl_config_new_by_mode((GdkGLConfigMode)(GDK_GL_MODE_RGB | GDK_GL_MODE_DOUBLE));
     if(!glconfig) glconfig = gdk_gl_config_new_by_mode(GDK_GL_MODE_RGB); // Hmm, can't find double buffered config
@@ -20,19 +22,24 @@ RenderArea::RenderArea(BaseObjectType *cobject, const Glib::RefPtr<Gnome::Glade:
   }
   
   signal_realize().connect(sigc::mem_fun(this, &RenderArea::onRealize));
+  signal_configure_event().connect(sigc::mem_fun(this, &RenderArea::onConfigureEvent));
+  signal_expose_event().connect(sigc::mem_fun(this, &RenderArea::onExposeEvent));
+  signal_scroll_event().connect(sigc::mem_fun(this, &RenderArea::onScrollEvent));
+  
+  Gtk::ToolButton *button;
+  xml->get_widget("ToolButtonZoomIn", button);
+  if(button)
+    button->signal_clicked().connect(sigc::bind(sigc::mem_fun(this, &RenderArea::zoom), 2, 0.5f, 0.5f));
+  
+  xml->get_widget("ToolButtonZoomOut", button);
+  if(button)
+    button->signal_clicked().connect(sigc::bind(sigc::mem_fun(this, &RenderArea::zoom), -2, 0.5f, 0.5f));
   
   gtk_widget_set_gl_capability(GTK_WIDGET(cobject), glconfig, NULL, TRUE, GDK_GL_RGBA_TYPE);
 }
 
-RenderArea::~RenderArea() {
-}
-
 void RenderArea::onRealize() {
-  GtkWidget *widget = GTK_WIDGET(gobj());
-  GdkGLContext *context = gtk_widget_get_gl_context(widget);
-  GdkGLDrawable *drawable = gtk_widget_get_gl_drawable(widget);
-  
-  if(!gdk_gl_drawable_gl_begin(drawable, context))
+  if(!gdkGLBegin())
     return;
   
   glClearColor(0, 0, 0, 0);
@@ -46,7 +53,108 @@ void RenderArea::onRealize() {
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
   
-  gdk_gl_drawable_gl_end(drawable);
+  gdkGLEnd();
+}
+
+bool RenderArea::onConfigureEvent(GdkEventConfigure *event) {
+  updateViewport();
+  return true;
+}
+
+bool RenderArea::onExposeEvent(GdkEventExpose *event) {
+  if(!gdkGLBegin())
+    return false;
+  
+  glClear(GL_COLOR_BUFFER_BIT);
+  
+  glMatrixMode(GL_MODELVIEW);
+  glPushMatrix();
+  
+  glScalef(scale, scale, 1);
+  glTranslatef(-x, -y, 0);
+  
+  
+  drawGrid();
+  
+  glMatrixMode(GL_MODELVIEW);
+  glPopMatrix();
+
+  
+  gdkSwapBuffers();
+  gdkGLEnd();
+  
+  return true;
+}
+
+bool RenderArea::onScrollEvent(GdkEventScroll *event) {
+  switch(event->direction) {
+    case GDK_SCROLL_UP:
+      zoom(1, event->x/get_width(), event->y/get_height());
+      return true;
+    case GDK_SCROLL_DOWN:
+      zoom(-1, event->x/get_width(), event->y/get_height());
+      return true;
+    default:
+      return false;
+  }
+}
+
+void RenderArea::zoom(int zoom, float x, float y) {
+  zoomLevel = std::max(std::min(zoomLevel + zoom, 50), -100);
+  scale = 100*std::pow(1.1f, zoomLevel);
+  
+  queue_draw();
+}
+
+void RenderArea::updateViewport() {
+  if(!gdkGLBegin())
+    return;
+  
+  glViewport(0, 0, get_width(), get_height());
+  
+  glMatrixMode(GL_PROJECTION);
+  glLoadIdentity();
+  
+  if(get_width() != 0 && get_height() != 0)
+    glScalef(2.0f/get_width(), -2.0f/get_height(), 1);
+  
+  gdkGLEnd();
+  
+  queue_draw();
+}
+
+void RenderArea::drawGrid() {
+  float depth = std::log10(scale)-0.75f;
+  float depth2 = std::floor(depth);
+  float step = std::pow(0.1f, depth2);
+  float f;
+  int i;
+  float x1 = x-get_width()/(2*scale), y1 = y-get_height()/(2*scale);
+  float x2 = x+get_width()/(2*scale), y2 = y+get_height()/(2*scale);
+  
+  
+  glLineWidth(1.0f);
+  
+  glBegin(GL_LINES);
+  
+  for(i = 0; 0.4f*(depth-depth2+i-1) < 0.5f; i++) {
+    f = std::min(0.4f*(depth-depth2+i), 0.5f);
+    glColor3f(f, f, f);
+    
+    for(f = x1 - std::fmod(x1, step) - step; f <= x2; f+=step) {
+      glVertex2f(f, y1);
+      glVertex2f(f, y2);
+    }
+    
+    for(f = y1 - std::fmod(y1, step) - step; f <= y2; f+=step) {
+      glVertex2f(x1, f);
+      glVertex2f(x2, f);
+    }
+    
+    step *= 10;
+  }
+  
+  glEnd();
 }
 
 }
diff --git a/src/Gui/RenderArea.h b/src/Gui/RenderArea.h
index 6695e09..d0b4ad3 100644
--- a/src/Gui/RenderArea.h
+++ b/src/Gui/RenderArea.h
@@ -11,12 +11,39 @@ namespace Gui {
 class RenderArea : public Gtk::DrawingArea {
   public:
     RenderArea(BaseObjectType *cobject, const Glib::RefPtr<Gnome::Glade::Xml> &xml);
-    virtual ~RenderArea();
-  
+    
   private:
     static GdkGLConfig *glconfig;
     
+    float x, y;
+    
+    int zoomLevel;
+    float scale;
+    
     void onRealize();
+    bool onConfigureEvent(GdkEventConfigure *event);
+    bool onExposeEvent(GdkEventExpose *event);
+    bool onScrollEvent(GdkEventScroll *event);
+    
+    void zoom(int zoom, float x = 0.5f, float y = 0.5f);
+    
+    void updateViewport();
+    
+    void drawGrid();
+    
+    bool gdkGLBegin() {
+      GtkWidget *widget = GTK_WIDGET(gobj());
+      
+      return gdk_gl_drawable_gl_begin(gtk_widget_get_gl_drawable(widget), gtk_widget_get_gl_context(widget));
+    }
+    
+    void gdkSwapBuffers() {
+      gdk_gl_drawable_swap_buffers(gtk_widget_get_gl_drawable(GTK_WIDGET(gobj())));
+    }
+    
+    void gdkGLEnd() {
+      gdk_gl_drawable_gl_end(gtk_widget_get_gl_drawable(GTK_WIDGET(gobj())));
+    }
 };
 
 }