0.5a: further revisions to merged ways, API->SWF error handling
[rails.git] / app / controllers / swf_controller.rb
1 class SwfController < ApplicationController
2         session :off
3         before_filter :check_read_availability
4
5 # to log:
6 # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
7 # $log.puts Time.new.to_s+','+Time.new.usec.to_s+": started GPS script"
8 # http://localhost:3000/api/0.4/swf/trackpoints?xmin=-2.32402605810577&xmax=-2.18386309423859&ymin=52.1546608755772&ymax=52.2272777906895&baselong=-2.25325793066437&basey=61.3948537948532&masterscale=5825.4222222222
9
10         # ====================================================================
11         # Public methods
12         
13         # ---- trackpoints      compile SWF of trackpoints
14
15         def trackpoints 
16         
17                 # -     Initialise
18         
19                 baselong        =params['baselong'].to_f
20                 basey           =params['basey'].to_f
21                 masterscale     =params['masterscale'].to_f
22         
23                 xmin=params['xmin'].to_f;
24                 xmax=params['xmax'].to_f;
25                 ymin=params['ymin'].to_f;
26                 ymax=params['ymax'].to_f;
27         
28                 # -     Begin movie
29         
30                 bounds_left  =0
31                 bounds_right =320*20
32                 bounds_bottom=0
33                 bounds_top   =240*20
34
35                 m =''
36                 m+=swfRecord(9,255.chr + 155.chr + 155.chr)                     #ƊBackground
37                 absx=0
38                 absy=0
39                 xl=yb= 9999999
40                 xr=yt=-9999999
41         
42                 # -     Send SQL for GPS tracks
43         
44                 b=''
45                 lasttime=0
46                 lastfile='-1'
47         
48                 if params['token']
49                   user=User.authenticate(:token => params[:token])
50                   sql="SELECT gps_points.latitude*0.0000001 AS lat,gps_points.longitude*0.0000001 AS lon,gpx_files.id AS fileid,UNIX_TIMESTAMP(gps_points.timestamp) AS ts "+
51                            " FROM gpx_files,gps_points "+
52                            "WHERE gpx_files.id=gpx_id "+
53                            "  AND gpx_files.user_id=#{user.id} "+
54                            "  AND "+OSM.sql_for_area(ymin,xmin,ymax,xmax,"gps_points.")+
55                            "  AND (gps_points.timestamp IS NOT NULL) "+
56                            "ORDER BY fileid DESC,ts "+
57                            "LIMIT 10000"
58                   else
59                         sql="SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,gpx_id AS fileid,UNIX_TIMESTAMP(timestamp) AS ts "+
60                                  " FROM gps_points "+
61                                  "WHERE "+OSM.sql_for_area(ymin,xmin,ymax,xmax,"gps_points.")+
62                                  "  AND (gps_points.timestamp IS NOT NULL) "+
63                                  "ORDER BY fileid DESC,ts "+
64                                  "LIMIT 10000"
65                 end
66                 gpslist=ActiveRecord::Base.connection.select_all sql
67         
68                 # - Draw GPS trace lines
69         
70                 r=startShape()
71                 gpslist.each do |row|
72                         xs=(long2coord(row['lon'].to_f,baselong,masterscale)*20).floor
73                         ys=(lat2coord(row['lat'].to_f ,basey   ,masterscale)*20).floor
74                         xl=[xs,xl].min; xr=[xs,xr].max
75                         yb=[ys,yb].min; yt=[ys,yt].max
76                         if (row['ts'].to_i-lasttime<180 and row['fileid']==lastfile and row['ts'].to_i!=lasttime)
77                                 b+=drawTo(absx,absy,xs,ys)
78                         else
79                                 b+=startAndMove(xs,ys,'01')
80                         end
81                         absx=xs.floor; absy=ys.floor
82                         lasttime=row['ts'].to_i
83                         lastfile=row['fileid']
84                         while b.length>80 do
85                                 r+=[b.slice!(0...80)].pack("B*")
86                         end
87                 end
88                 
89                 #   (Unwayed segments removed)
90         
91                 # - Write shape
92         
93                 b+=endShape()
94                 r+=[b].pack("B*")
95                 m+=swfRecord(2,packUI16(1) + packRect(xl,xr,yb,yt) + r)
96                 m+=swfRecord(4,packUI16(1) + packUI16(1))
97                 
98                 # -     Create Flash header and write to browser
99         
100                 m+=swfRecord(1,'')                                                                      # Show frame
101                 m+=swfRecord(0,'')                                                                      # End
102                 
103                 m=packRect(bounds_left,bounds_right,bounds_bottom,bounds_top) + 0.chr + 12.chr + packUI16(1) + m
104                 m='FWS' + 6.chr + packUI32(m.length+8) + m
105         
106                 render :text => m, :content_type => "application/x-shockwave-flash"
107         end
108
109         private
110
111         # =======================================================================
112         # SWF functions
113         
114         # -----------------------------------------------------------------------
115         # Line-drawing
116
117         def startShape
118                 s =0.chr                                                                                # No fill styles
119                 s+=2.chr                                                                                # Two line styles
120                 s+=packUI16(5) + 0.chr + 255.chr + 255.chr              # Width 5, RGB #00FFFF
121                 s+=packUI16(5) + 255.chr + 0.chr + 255.chr              # Width 5, RGB #FF00FF
122                 s+=34.chr                                                                               # 2 fill, 2 line index bits
123                 s
124         end
125         
126         def endShape
127                 '000000'
128         end
129         
130         def startAndMove(x,y,col)
131                 d='001001'                                                                              # Line style change, moveTo
132                 l =[lengthSB(x),lengthSB(y)].max
133                 d+=sprintf("%05b%0#{l}b%0#{l}b",l,x,y)
134                 d+=col                                                                                  # Select line style
135         end
136         
137         def drawTo(absx,absy,x,y)
138                 d='11'                                                                                  # TypeFlag, EdgeFlag
139                 dx=x-absx
140                 dy=y-absy
141                 
142                 l =[lengthSB(dx),lengthSB(dy)].max
143                 d+=sprintf("%04b",l-2)
144                 d+='1'                                                                                  # GeneralLine
145                 d+=sprintf("%0#{l}b%0#{l}b",dx,dy)
146         end
147
148         # -----------------------------------------------------------------------
149         # Specific data types
150
151         def swfRecord(id,r)
152                 if r.length>62
153                         return packUI16((id<<6)+0x3F) + packUI32(r.length) + r
154                 else
155                         return packUI16((id<<6)+r.length) + r
156                 end
157         end
158
159         def packRect(a,b,c,d)
160                 l=[lengthSB(a),
161                    lengthSB(b),
162                    lengthSB(c),
163                    lengthSB(d)].max
164                 n=sprintf("%05b%0#{l}b%0#{l}b%0#{l}b%0#{l}b",l,a,b,c,d)
165                 [n].pack("B*")
166         end
167
168         # -----------------------------------------------------------------------
169         # Generic pack functions
170         
171         def packUI16(n)
172                 [n.floor].pack("v")
173         end
174         
175         def packUI32(n)
176                 [n.floor].pack("V")
177         end
178         
179         # Find number of bits required to store arbitrary-length binary
180         
181         def lengthSB(n)
182                 Math.frexp(n+ (n==0?1:0) )[1]+1
183         end
184         
185         # ====================================================================
186         # Co-ordinate conversion
187         # (this is duplicated from amf_controller, should probably share)
188         
189         def lat2coord(a,basey,masterscale)
190                 -(lat2y(a)-basey)*masterscale+250
191         end
192         
193         def long2coord(a,baselong,masterscale)
194                 (a-baselong)*masterscale+350
195         end
196         
197         def lat2y(a)
198                 180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
199         end
200
201         def sqlescape(a)
202                 a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
203         end
204
205 end