From: Andy Spencer <andy753421@gmail.com>
Date: Mon, 8 Feb 2010 05:38:00 +0000 (+0000)
Subject: Sort of fix panning when rotated
X-Git-Tag: v0.4~72
X-Git-Url: http://pileus.org/git/?p=grits;a=commitdiff_plain;h=aa67a046ea950755834700466782756b273bdf24

Sort of fix panning when rotated

Use the current rotation to move the expected direction. This isn't
accurate because it uses lat-lon which aren't Cartesian coordinates.
---

diff --git a/src/gis-viewer.c b/src/gis-viewer.c
index a4d7dc5..5b89a71 100644
--- a/src/gis-viewer.c
+++ b/src/gis-viewer.c
@@ -211,13 +211,23 @@ void gis_viewer_get_location(GisViewer *self, gdouble *lat, gdouble *lon, gdoubl
 	*elev = self->location[2];
 }
 
-void gis_viewer_pan(GisViewer *self, gdouble lat, gdouble lon, gdouble elev)
+void gis_viewer_pan(GisViewer *self, gdouble forward, gdouble sideways, gdouble up)
 {
 	g_assert(GIS_IS_VIEWER(self));
-	g_debug("GisViewer: pan - lat=%8.3f, lon=%8.3f, elev=%8.3f", lat, lon, elev);
-	self->location[0] += lat;
-	self->location[1] += lon;
-	self->location[2] += elev;
+	g_debug("GisViewer: pan - forward=%8.3f, sideways=%8.3f, up=%8.3f",
+			forward, sideways, up);
+	gdouble dist   = sqrt(forward*forward + sideways*sideways);
+	gdouble angle1 = deg2rad(self->rotation[2]);
+	gdouble angle2 = atan2(sideways, forward);
+	gdouble angle  = angle1 + angle2;
+	g_message("pan: dist=%f, angle=%f+%f=%f move=%f,%f",
+			dist, angle1, angle2, angle,
+			dist*cos(angle),
+			dist*sin(angle));
+	/* This isn't accurate, but it's usable */
+	self->location[0] += dist*cos(angle);
+	self->location[1] += dist*sin(angle);
+	self->location[2] += up;
 	_gis_viewer_fix_location(self);
 	_gis_viewer_emit_location_changed(self);
 }
diff --git a/src/gis-viewer.h b/src/gis-viewer.h
index c20cac8..ea07348 100644
--- a/src/gis-viewer.h
+++ b/src/gis-viewer.h
@@ -92,8 +92,8 @@ gchar *gis_viewer_get_time(GisViewer *viewer);
 
 void gis_viewer_set_location(GisViewer *viewer, gdouble  lat, gdouble  lon, gdouble  elev);
 void gis_viewer_get_location(GisViewer *viewer, gdouble *lat, gdouble *lon, gdouble *elev);
-void gis_viewer_pan         (GisViewer *viewer, gdouble  lat, gdouble  lon, gdouble  elev);
-void gis_viewer_zoom        (GisViewer *viewer, gdouble  scale);
+void gis_viewer_pan(GisViewer *self, gdouble forward, gdouble sideways, gdouble up);
+void gis_viewer_zoom(GisViewer *viewer, gdouble  scale);
 
 void gis_viewer_set_rotation(GisViewer *viewer, gdouble  x, gdouble  y, gdouble  z);
 void gis_viewer_get_rotation(GisViewer *viewer, gdouble *x, gdouble *y, gdouble *z);