11 files changed, 197 insertions, 111 deletions

diff --git a/src/controller/actions/zoom.c b/src/controller/actions/zoom.c
index b8e54cc..7209e85 100644
--- a/src/controller/actions/zoom.c
+++ b/src/controller/actions/zoom.c
@@ -11,52 +11,40 @@
 #define S state0
 
 void
-zoom (int x1, int y1, int x2, int y2)
+zoom (double x1, double y1, double x2, double y2)
 {
+  S.zoom.active = true;
+  
+  S.zoom.coords[0] = x1;
+  S.zoom.coords[1] = x2;
+  S.zoom.coords[2] = y1;
+  S.zoom.coords[3] = y2;
+
   /*
-   * Convert the selection boundary from window coordinates to
-   * world coordinates.
+   * Preserve the aspect ratio.  First convert the selection to the
+   * aspect ratio of the original geometry. The world is a square so
+   * convert the zoom region to a square. The reshape callback
+   * performs step two of converting the squarified zoom region to the
+   * aspect ratio of the window. This is done in reshape as the window
+   * may change while the zoom region is held the same.
    */
-  glMatrixMode (GL_MODELVIEW);
-  glLoadIdentity ();
-  GLdouble model[16];
-  glGetDoublev (GL_MODELVIEW_MATRIX, model);
-  GLdouble projection[16];
-  glGetDoublev (GL_PROJECTION_MATRIX, projection);
+  double width = S.zoom.coords[1] - S.zoom.coords[0];
+  double height = S.zoom.coords[3] - S.zoom.coords[2];
+  double difference = fabs(width - height);
+
+  if (width > height)
+    {
+      S.zoom.coords[2] -= 0.5 * difference;
+      S.zoom.coords[3] += 0.5 * difference;
+    }
+  else
+    {
+      S.zoom.coords[0] -= 0.5 * difference;
+      S.zoom.coords[1] += 0.5 * difference;
+    }
+
   GLint viewport[4];
   glGetIntegerv (GL_VIEWPORT, viewport);
-
-  check_error (__FILE__, __LINE__);
-  
-  GLdouble start_position[3];
-  gluUnProject (x1,
-                y1,
-                0,
-                model,
-                projection,
-                viewport,
-                &start_position[0],
-                &start_position[1], &start_position[2]);
-  
-  check_error (__FILE__, __LINE__);
-  
-  GLdouble end_position[3];
-  gluUnProject (x2,
-                y2,
-                0,
-                model,
-                projection,
-                viewport,
-                &end_position[0], &end_position[1], &end_position[2]);
-  
-  check_error (__FILE__, __LINE__);
-  
-  S.zoom.active = true;
-  S.zoom.coords[0] = fmin (start_position[0], end_position[0]);
-  S.zoom.coords[1] = fmax (start_position[0], end_position[0]);
-  S.zoom.coords[2] = fmin (start_position[1], end_position[1]);
-  S.zoom.coords[3] = fmax (start_position[1], end_position[1]);
-  
   reshape (viewport[2], viewport[3]);
   
   glutPostRedisplay ();