+ # ====================================================================
+ # Public methods
+
+ # ---- trackpoints compile SWF of trackpoints
+
+ def trackpoints
+ # - Initialise
+
+ baselong = params["baselong"].to_f
+ basey = params["basey"].to_f
+ masterscale = params["masterscale"].to_f
+
+ bbox = BoundingBox.new(params["xmin"], params["ymin"],
+ params["xmax"], params["ymax"])
+ start = params["start"].to_i
+
+ # - Begin movie
+
+ bounds_left = 0
+ bounds_right = 320 * 20
+ bounds_bottom = 0
+ bounds_top = 240 * 20
+
+ m = ""
+ m += swf_record(9, 255.chr + 155.chr + 155.chr) # Background
+ absx = 0
+ absy = 0
+ xl = yb = 9999999
+ xr = yt = -9999999
+
+ # - Send SQL for GPS tracks
+
+ b = ""
+ lasttime = 0
+ lasttrack = lastfile = "-1"
+
+ if params["token"]
+ user = User.authenticate(:token => params[:token])
+ sql = "SELECT gps_points.latitude*0.0000001 AS lat,gps_points.longitude*0.0000001 AS lon,gpx_files.id AS fileid," + " EXTRACT(EPOCH FROM gps_points.timestamp) AS ts, gps_points.trackid AS trackid " + " FROM gpx_files,gps_points " + "WHERE gpx_files.id=gpx_id " + " AND gpx_files.user_id=#{user.id} " + " AND " + OSM.sql_for_area(bbox, "gps_points.") + " AND (gps_points.timestamp IS NOT NULL) " + "ORDER BY fileid DESC,ts " + "LIMIT 10000 OFFSET #{start}"
+ else
+ sql = "SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,gpx_id AS fileid," + " EXTRACT(EPOCH FROM timestamp) AS ts, gps_points.trackid AS trackid " + " FROM gps_points " + "WHERE " + OSM.sql_for_area(bbox, "gps_points.") + " AND (gps_points.timestamp IS NOT NULL) " + "ORDER BY fileid DESC,ts " + "LIMIT 10000 OFFSET #{start}"
+ end
+ gpslist = ActiveRecord::Base.connection.select_all sql
+
+ # - Draw GPS trace lines
+
+ r = start_shape
+ gpslist.each do |row|
+ xs = (long2coord(row["lon"].to_f, baselong, masterscale) * 20).floor
+ ys = (lat2coord(row["lat"].to_f, basey, masterscale) * 20).floor
+ xl = [xs, xl].min
+ xr = [xs, xr].max
+ yb = [ys, yb].min
+ yt = [ys, yt].max
+ if row["ts"].to_i - lasttime > 180 || row["fileid"] != lastfile || row["trackid"] != lasttrack # or row['ts'].to_i==lasttime
+ b += start_and_move(xs, ys, "01")
+ absx = xs.floor
+ absy = ys.floor
+ end
+ b += draw_to(absx, absy, xs, ys)
+ absx = xs.floor
+ absy = ys.floor
+ lasttime = row["ts"].to_i
+ lastfile = row["fileid"]
+ lasttrack = row["trackid"]
+ r += [b.slice!(0...80)].pack("B*") while b.length > 80
+ end
+
+ # (Unwayed segments removed)
+
+ # - Write shape
+
+ b += end_shape
+ r += [b].pack("B*")
+ m += swf_record(2, pack_u16(1) + pack_rect(xl, xr, yb, yt) + r)
+ m += swf_record(4, pack_u16(1) + pack_u16(1))
+
+ # - Create Flash header and write to browser
+
+ m += swf_record(1, "") # Show frame
+ m += swf_record(0, "") # End
+
+ m = pack_rect(bounds_left, bounds_right, bounds_bottom, bounds_top) + 0.chr + 12.chr + pack_u16(1) + m
+ m = "FWS" + 6.chr + pack_u32(m.length + 8) + m
+
+ render :body => m, :content_type => "application/x-shockwave-flash"
+ end
+
+ private
+
+ # =======================================================================
+ # SWF functions
+
+ # -----------------------------------------------------------------------
+ # Line-drawing
+
+ def start_shape
+ s = 0.chr # No fill styles
+ s += 2.chr # Two line styles
+ s += pack_u16(0) + 0.chr + 255.chr + 255.chr # Width 5, RGB #00FFFF
+ s += pack_u16(0) + 255.chr + 0.chr + 255.chr # Width 5, RGB #FF00FF
+ s += 34.chr # 2 fill, 2 line index bits
+ s
+ end
+
+ def end_shape
+ "000000"
+ end
+
+ def start_and_move(x, y, col)
+ d = "001001" # Line style change, moveTo
+ l = [length_sb(x), length_sb(y)].max
+ d += format("%05b%0*b%0*b", l, l, x, l, y)
+ d += col # Select line style
+ d
+ end
+
+ def draw_to(absx, absy, x, y)
+ dx = x - absx
+ dy = y - absy
+
+ # Split the line up if there's anything>16383, because
+ # that would overflow the 4 bits allowed for length
+ mstep = [dx.abs / 16383, dy.abs / 16383, 1].max.ceil
+ xstep = dx / mstep
+ ystep = dy / mstep
+ d = ""
+ 1.upto(mstep).each do
+ d += draw_section(x, y, x + xstep, y + ystep)
+ x += xstep
+ y += ystep
+ end
+ d
+ end
+
+ def draw_section(x1, y1, x2, y2)
+ d = "11" # TypeFlag, EdgeFlag
+ dx = x2 - x1
+ dy = y2 - y1
+ l = [length_sb(dx), length_sb(dy)].max
+ d += format("%04b", l - 2)
+ d += "1" # GeneralLine
+ d += format("%0*b%0*b", l, dx, l, dy)
+ d
+ end
+
+ # -----------------------------------------------------------------------
+ # Specific data types
+
+ # SWF data block type
+
+ def swf_record(id, r)
+ if r.length > 62
+ # Long header: tag id, 0x3F, length
+ pack_u16((id << 6) + 0x3F) + pack_u32(r.length) + r
+ else
+ # Short header: tag id, length
+ pack_u16((id << 6) + r.length) + r
+ end
+ end
+
+ # SWF RECT type
+
+ def pack_rect(a, b, c, d)
+ l = [length_sb(a),
+ length_sb(b),
+ length_sb(c),
+ length_sb(d)].max
+ # create binary string (00111001 etc.) - 5-byte length, then bbox
+ n = format("%05b%0*b%0*b%0*b%0*b", l, l, a, l, b, l, c, l, d)
+ # pack into byte string
+ [n].pack("B*")
+ end
+
+ # -----------------------------------------------------------------------
+ # Generic pack functions
+
+ def pack_u16(n)
+ [n.floor].pack("v")
+ end
+
+ def pack_u32(n)
+ [n.floor].pack("V")
+ end
+
+ # Find number of bits required to store arbitrary-length binary
+
+ def length_sb(n)
+ Math.frexp(n + (n.zero? ? 1 : 0))[1] + 1
+ end
+
+ # ====================================================================
+ # Co-ordinate conversion
+ # (this is duplicated from amf_controller, should probably share)
+
+ def lat2coord(a, basey, masterscale)
+ -(lat2y(a) - basey) * masterscale
+ end
+
+ def long2coord(a, baselong, masterscale)
+ (a - baselong) * masterscale
+ end
+
+ def lat2y(a)
+ 180 / Math::PI * Math.log(Math.tan(Math::PI / 4 + a * (Math::PI / 180) / 2))
+ end
projects / rails.git / blobdiff