Adds skyview rotation support to xgps and xgpsspeed.

This adds an optional argument to rotate the skyview display, making
it possible to orient it correctly based on the direction one is
actually facing.  The specified heading is positioned at the top.

This edit does not update contrib/webgps.py, which is somewhat
more complicated to fix due to the Javascript involvement.

TESTED:
Ran both programs with and without the -r or --rotate option.

Signed-off-by: Gary E. Miller <gem@rellim.com>

1 files changed, 44 insertions, 31 deletions

diff --git a/xgpsspeed b/xgpsspeed
index 277b575a..29a6fc7d 100755
--- a/xgpsspeed
+++ b/xgpsspeed
@@ -228,7 +228,7 @@ class NauticalSpeedometer(Speedometer):
     HEADING_SAT_GAP = 0.8
     SAT_SIZE = 10  # radius of the satellite circle in skyview
 
-    def __init__(self, speed_unit=None, maxspeed=100):
+    def __init__(self, speed_unit=None, maxspeed=100, rotate=0.0):
         Speedometer.__init__(self, speed_unit)
         self.connect('size-allocate', self.on_size_allocate)
         self.width = self.height = 0
@@ -240,9 +240,9 @@ class NauticalSpeedometer(Speedometer):
         self.satellites = []
         self.last_heading = 0
         self.maxspeed = int(maxspeed)
+        self.rotate = radians(rotate)
 
-    @staticmethod
-    def polar2xy(radius, angle, polex, poley):
+    def polar2xy(self, radius, angle, polex, poley):
         '''convert Polar coordinate to Cartesian coordinate system
         the y axis in pygtk points downward
         Args:
@@ -250,6 +250,7 @@ class NauticalSpeedometer(Speedometer):
            angle: azimuth from from Polar coordinate system, in radian
            polex and poley are the Cartesian coordinate of the pole
         return a tuple contains (x, y)'''
+        angle = (angle + self.rotate) % (pi * 2)  # Note reversed sense
         return (polex + cos(angle) * radius, poley - sin(angle) * radius)
 
     def on_size_allocate(self, _unused, allocation):
@@ -306,12 +307,12 @@ class NauticalSpeedometer(Speedometer):
         for i in range(11):
             # draw the large ticks
             alpha = (8 - i) * pi / 6
-            self.cr.move_to(*NauticalSpeedometer.polar2xy(rspeed, alpha, x, y))
+            self.cr.move_to(*self.polar2xy(rspeed, alpha, x, y))
             self.cr.set_line_width(radius / 100)
-            self.cr.line_to(*NauticalSpeedometer.polar2xy(rspeed - s_long, alpha, x, y))
+            self.cr.line_to(*self.polar2xy(rspeed - s_long, alpha, x, y))
             self.cr.stroke()
             self.cr.set_line_width(radius / 200)
-            xf, yf = NauticalSpeedometer.polar2xy(rspeed + 10, alpha, x, y)
+            xf, yf = self.polar2xy(rspeed + 10, alpha, x, y)
             stxt = (self.maxspeed // 10) * i
             self.draw_text(xf, yf, stxt, fontsize=radius / 15)
 
@@ -319,14 +320,14 @@ class NauticalSpeedometer(Speedometer):
             # middle tick
             alpha = (8 - i) * pi / 6
             beta = (17 - 2 * i) * pi / 12
-            self.cr.move_to(*NauticalSpeedometer.polar2xy(rspeed, beta, x, y))
-            self.cr.line_to(*NauticalSpeedometer.polar2xy(rspeed - s_middle, beta, x, y))
+            self.cr.move_to(*self.polar2xy(rspeed, beta, x, y))
+            self.cr.line_to(*self.polar2xy(rspeed - s_middle, beta, x, y))
 
             #  short tick
             for n in range(10):
                 gamma = alpha + n * pi / 60
-                self.cr.move_to(*NauticalSpeedometer.polar2xy(rspeed, gamma, x, y))
-                self.cr.line_to(*NauticalSpeedometer.polar2xy(rspeed - s_short, gamma, x, y))
+                self.cr.move_to(*self.polar2xy(rspeed, gamma, x, y))
+                self.cr.line_to(*self.polar2xy(rspeed - s_short, gamma, x, y))
 
         # draw the heading arc
         self.cr.new_sub_path()
@@ -342,7 +343,7 @@ class NauticalSpeedometer(Speedometer):
             label = str(n * 90)
             # self.cr.set_source_rgba(0, 1, 0)
             # radius * (1 + NauticalSpeedometer.HEADING_SAT_GAP),
-            tbox_x, tbox_y = NauticalSpeedometer.polar2xy(
+            tbox_x, tbox_y = self.polar2xy(
                 radius * 0.88,
                 (1 - n) * pi / 2,
                 x, y)
@@ -359,13 +360,14 @@ class NauticalSpeedometer(Speedometer):
         self.cr.set_source_rgba(0, 0, 0)
 
         self.cr.arc(x, y, skyradius * 2 / 3, 0, 2 * pi)
+        self.cr.move_to(x + skyradius / 3, y)  # Avoid line connecting circles
         self.cr.arc(x, y, skyradius / 3, 0, 2 * pi)
 
         # draw the cross hair
-        self.cr.move_to(x - skyradius, y)
-        self.cr.line_to(x + skyradius, y)
-        self.cr.move_to(x, y - skyradius)
-        self.cr.line_to(x, y + skyradius)
+        self.cr.move_to(*self.polar2xy(skyradius, 1.5 * pi, x, y))
+        self.cr.line_to(*self.polar2xy(skyradius, 0.5 * pi, x, y))
+        self.cr.move_to(*self.polar2xy(skyradius, 0.0, x, y))
+        self.cr.line_to(*self.polar2xy(skyradius, pi, x, y))
         self.cr.set_line_width(radius / 200)
         self.cr.stroke()
 
@@ -376,22 +378,22 @@ class NauticalSpeedometer(Speedometer):
         # draw the large ticks
         for i in range(12):
             agllong = i * pi / 6
-            self.cr.move_to(*NauticalSpeedometer.polar2xy(radius - long_inset, agllong, x, y))
-            self.cr.line_to(*NauticalSpeedometer.polar2xy(radius, agllong, x, y))
+            self.cr.move_to(*self.polar2xy(radius - long_inset, agllong, x, y))
+            self.cr.line_to(*self.polar2xy(radius, agllong, x, y))
             self.cr.set_line_width(radius / 100)
             self.cr.stroke()
             self.cr.set_line_width(radius / 200)
 
             # middle tick
             aglmid = (i + 0.5) * pi / 6
-            self.cr.move_to(*NauticalSpeedometer.polar2xy(radius - mid_inset, aglmid, x, y))
-            self.cr.line_to(*NauticalSpeedometer.polar2xy(radius, aglmid, x, y))
+            self.cr.move_to(*self.polar2xy(radius - mid_inset, aglmid, x, y))
+            self.cr.line_to(*self.polar2xy(radius, aglmid, x, y))
 
             #  short tick
             for n in range(1, 10):
                 aglshrt = agllong + n * pi / 60
-                self.cr.move_to(*NauticalSpeedometer.polar2xy(radius - short_inset, aglshrt, x, y))
-                self.cr.line_to(*NauticalSpeedometer.polar2xy(radius, aglshrt, x, y))
+                self.cr.move_to(*self.polar2xy(radius - short_inset, aglshrt, x, y))
+                self.cr.line_to(*self.polar2xy(radius, aglshrt, x, y))
             self.cr.stroke()
 
     def draw_heading(self, trig_height, heading, radius, x, y):
@@ -419,16 +421,16 @@ class NauticalSpeedometer(Speedometer):
         self.cr.stroke()
 
         # heading text
-        (tbox_x, tbox_y) = NauticalSpeedometer.polar2xy(radius * 1.1, h, x, y)
+        (tbox_x, tbox_y) = self.polar2xy(radius * 1.1, h, x, y)
         self.draw_text(tbox_x, tbox_y, int(heading), fontsize=radius / 15)
 
         # the ship shape, based on test and try
         shiplen = radius * NauticalSpeedometer.HEADING_SAT_GAP / 4
-        xh, yh = NauticalSpeedometer.polar2xy(shiplen * 2.3, h, x, y)
-        xa, ya = NauticalSpeedometer.polar2xy(shiplen * 2.2, h + pi - 0.3, x, y)
-        xb, yb = NauticalSpeedometer.polar2xy(shiplen * 2.2, h + pi + 0.3, x, y)
-        xc, yc = NauticalSpeedometer.polar2xy(shiplen * 1.4, h - pi / 5, x, y)
-        xd, yd = NauticalSpeedometer.polar2xy(shiplen * 1.4, h + pi / 5, x, y)
+        xh, yh = self.polar2xy(shiplen * 2.3, h, x, y)
+        xa, ya = self.polar2xy(shiplen * 2.2, h + pi - 0.3, x, y)
+        xb, yb = self.polar2xy(shiplen * 2.2, h + pi + 0.3, x, y)
+        xc, yc = self.polar2xy(shiplen * 1.4, h - pi / 5, x, y)
+        xd, yd = self.polar2xy(shiplen * 1.4, h + pi / 5, x, y)
 
         self.cr.set_source_rgba(0, 0.3, 0.2, 0.5)
         self.cr.move_to(xa, ya)
@@ -460,7 +462,7 @@ class NauticalSpeedometer(Speedometer):
         self.cr.set_line_width(2)
         self.cr.set_source_rgb(0, 0, 0)
 
-        x0, y0 = NauticalSpeedometer.polar2xy(radius * (90 - el) // 90, h, x, y)
+        x0, y0 = self.polar2xy(radius * (90 - el) // 90, h, x, y)
 
         self.cr.new_sub_path()
         if gps.is_sbas(satsoup['PRN']):
@@ -515,7 +517,7 @@ class NauticalSpeedometer(Speedometer):
 
 class Main(object):
     def __init__(self, host='localhost', port='2947', device=None, debug=0,
-                 speed_unit=None, maxspeed=0, nautical=False):
+                 speed_unit=None, maxspeed=0, nautical=False, rotate=0.0):
         self.host = host
         self.port = port
         self.device = device
@@ -523,6 +525,7 @@ class Main(object):
         self.speed_unit = speed_unit
         self.maxspeed = maxspeed
         self.nautical = nautical
+        self.rotate = rotate
         self.window = Gtk.Window(Gtk.WindowType.TOPLEVEL)
         if not self.window.get_display():
             raise Exception("Can't open display")
@@ -531,7 +534,8 @@ class Main(object):
             self.window.set_size_request(500, 550)
             self.widget = NauticalSpeedometer(
                 speed_unit=self.speed_unit,
-                maxspeed=self.maxspeed)
+                maxspeed=self.maxspeed,
+                rotate=self.rotate)
         else:
             self.widget = LandSpeedometer(speed_unit=self.speed_unit)
         self.window.connect('delete_event', self.delete_event)
@@ -735,6 +739,14 @@ if __name__ == '__main__':
         type='int',
         help='Set level of debug. Must be integer. [Default 0]'
     )
+    parser.add_option(
+        '--rotate',
+        dest='rotate',
+        default=0,
+        action='store',
+        type='float',
+        help='Rotation of skyview ("up" direction) in degrees. [Default 0]'
+    )
     (options, args) = parser.parse_args()
     if args:
         arg = args[0].split(':')
@@ -755,5 +767,6 @@ if __name__ == '__main__':
         speed_unit=options.speedunits,
         maxspeed=options.maxspeed,
         nautical=options.nautical,
-        debug=options.debug
+        debug=options.debug,
+        rotate=options.rotate,
     ).run()