[grits] Speed up movement when at low elevation

[Andy Spencer <andys src gnome org>]

commit b64f8e8da2b711ec351a2cd4d2ae020648e4326d
Author: Andy Spencer <andy753421 gmail com>
Date:   Sat Jul 30 21:14:53 2011 +0000

    Speed up movement when at low elevation

 src/grits-viewer.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/src/grits-viewer.c b/src/grits-viewer.c
index bfc704b..2f3b53e 100644
--- a/src/grits-viewer.c
+++ b/src/grits-viewer.c
@@ -160,9 +160,10 @@ static gboolean on_motion_notify(GritsViewer *viewer, GdkEventMotion *event, gpo
 {
 	gdouble x = viewer->drag_x - event->x;
 	gdouble y = viewer->drag_y - event->y;
-	gdouble lat, lon, elev, scale;
+	gdouble lat, lon, elev, scale, rx, ry, rz;
 	grits_viewer_get_location(GRITS_VIEWER(viewer), &lat, &lon, &elev);
-	scale = elev/EARTH_R/15;
+	grits_viewer_get_rotation(GRITS_VIEWER(viewer), &rx,  &ry,  &rz);
+	scale = (elev/EARTH_R/15) * (sin(deg2rad(ABS(rx)))*4+1);
 	switch (viewer->drag_mode) {
 	case GRITS_DRAG_PAN:  grits_viewer_pan(viewer, -y*scale, x*scale, 0); break;
 	case GRITS_DRAG_ZOOM: grits_viewer_zoom(viewer, pow(2, -y/500)); break;