# ====================================================================
# Public methods
-
+
# ---- trackpoints compile SWF of trackpoints
- def 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
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,"+
"LIMIT 10000 OFFSET #{start}"
end
gpslist=ActiveRecord::Base.connection.select_all sql
-
+
# - Draw GPS trace lines
-
+
r=startShape()
gpslist.each do |row|
xs=(long2coord(row['lon'].to_f,baselong,masterscale)*20).floor
r+=[b.slice!(0...80)].pack("B*")
end
end
-
+
# (Unwayed segments removed)
-
+
# - Write shape
-
+
b+=endShape()
r+=[b].pack("B*")
m+=swfRecord(2,packUI16(1) + packRect(xl,xr,yb,yt) + r)
m+=swfRecord(4,packUI16(1) + packUI16(1))
-
+
# - Create Flash header and write to browser
-
+
m+=swfRecord(1,'') # Show frame
m+=swfRecord(0,'') # End
-
+
m=packRect(bounds_left,bounds_right,bounds_bottom,bounds_top) + 0.chr + 12.chr + packUI16(1) + m
m='FWS' + 6.chr + packUI32(m.length+8) + m
-
+
render :text => m, :content_type => "application/x-shockwave-flash"
end
# =======================================================================
# SWF functions
-
+
# -----------------------------------------------------------------------
# Line-drawing
s+=34.chr # 2 fill, 2 line index bits
s
end
-
+
def endShape
'000000'
end
-
+
def startAndMove(x,y,col)
d='001001' # Line style change, moveTo
l =[lengthSB(x),lengthSB(y)].max
d+=sprintf("%05b%0#{l}b%0#{l}b",l,x,y)
d+=col # Select line style
end
-
+
def drawTo(absx,absy,x,y)
dx=x-absx
dy=y-absy
end
d
end
-
+
def drawSection(x1,y1,x2,y2)
d='11' # TypeFlag, EdgeFlag
dx=x2-x1
# -----------------------------------------------------------------------
# Generic pack functions
-
+
def packUI16(n)
[n.floor].pack("v")
end
-
+
def packUI32(n)
[n.floor].pack("V")
end
-
+
# Find number of bits required to store arbitrary-length binary
-
+
def lengthSB(n)
Math.frexp(n+ (n==0?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