Potlatch 1.3
[rails.git] / app / controllers / swf_controller.rb
1 class SwfController < ApplicationController
2         before_filter :check_api_readable
3
4 # to log:
5 # RAILS_DEFAULT_LOGGER.error("Args: #{args[0]}, #{args[1]}, #{args[2]}, #{args[3]}")
6 # $log.puts Time.new.to_s+','+Time.new.usec.to_s+": started GPS script"
7 # 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
8
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                 start=params['start'].to_i;
28         
29                 # -     Begin movie
30         
31                 bounds_left  =0
32                 bounds_right =320*20
33                 bounds_bottom=0
34                 bounds_top   =240*20
35
36                 m =''
37                 m+=swfRecord(9,255.chr + 155.chr + 155.chr)                     # Background
38                 absx=0
39                 absy=0
40                 xl=yb= 9999999
41                 xr=yt=-9999999
42         
43                 # -     Send SQL for GPS tracks
44         
45                 b=''
46                 lasttime=0
47                 lasttrack=lastfile='-1'
48         
49                 if params['token']
50                   user=User.authenticate(:token => params[:token])
51                   sql="SELECT gps_points.latitude*0.0000001 AS lat,gps_points.longitude*0.0000001 AS lon,gpx_files.id AS fileid,"+
52                        "      EXTRACT(EPOCH FROM gps_points.timestamp) AS ts, gps_points.trackid AS trackid "+
53                            " FROM gpx_files,gps_points "+
54                            "WHERE gpx_files.id=gpx_id "+
55                            "  AND gpx_files.user_id=#{user.id} "+
56                            "  AND "+OSM.sql_for_area(ymin,xmin,ymax,xmax,"gps_points.")+
57                            "  AND (gps_points.timestamp IS NOT NULL) "+
58                            "ORDER BY fileid DESC,ts "+
59                            "LIMIT 10000 OFFSET #{start}"
60                   else
61                         sql="SELECT latitude*0.0000001 AS lat,longitude*0.0000001 AS lon,gpx_id AS fileid,"+
62                              "      EXTRACT(EPOCH FROM timestamp) AS ts, gps_points.trackid AS trackid "+
63                                  " FROM gps_points "+
64                                  "WHERE "+OSM.sql_for_area(ymin,xmin,ymax,xmax,"gps_points.")+
65                                  "  AND (gps_points.timestamp IS NOT NULL) "+
66                                  "ORDER BY fileid DESC,ts "+
67                                  "LIMIT 10000 OFFSET #{start}"
68                 end
69                 gpslist=ActiveRecord::Base.connection.select_all sql
70         
71                 # - Draw GPS trace lines
72         
73                 r=startShape()
74                 gpslist.each do |row|
75                         xs=(long2coord(row['lon'].to_f,baselong,masterscale)*20).floor
76                         ys=(lat2coord(row['lat'].to_f ,basey   ,masterscale)*20).floor
77                         xl=[xs,xl].min; xr=[xs,xr].max
78                         yb=[ys,yb].min; yt=[ys,yt].max
79                         if row['ts'].to_i-lasttime>180 or row['fileid']!=lastfile or row['trackid']!=lasttrack #or row['ts'].to_i==lasttime
80                           b+=startAndMove(xs,ys,'01')
81                           absx=xs.floor; absy=ys.floor
82       end
83                   b+=drawTo(absx,absy,xs,ys)
84                         absx=xs.floor; absy=ys.floor
85                         lasttime=row['ts'].to_i
86                         lastfile=row['fileid']
87                         lasttrack=row['trackid']
88                         while b.length>80 do
89                                 r+=[b.slice!(0...80)].pack("B*")
90                         end
91                 end
92                 
93                 #   (Unwayed segments removed)
94         
95                 # - Write shape
96         
97                 b+=endShape()
98                 r+=[b].pack("B*")
99                 m+=swfRecord(2,packUI16(1) + packRect(xl,xr,yb,yt) + r)
100                 m+=swfRecord(4,packUI16(1) + packUI16(1))
101                 
102                 # -     Create Flash header and write to browser
103         
104                 m+=swfRecord(1,'')                                                                      # Show frame
105                 m+=swfRecord(0,'')                                                                      # End
106                 
107                 m=packRect(bounds_left,bounds_right,bounds_bottom,bounds_top) + 0.chr + 12.chr + packUI16(1) + m
108                 m='FWS' + 6.chr + packUI32(m.length+8) + m
109         
110                 render :text => m, :content_type => "application/x-shockwave-flash"
111         end
112
113         private
114
115         # =======================================================================
116         # SWF functions
117         
118         # -----------------------------------------------------------------------
119         # Line-drawing
120
121         def startShape
122                 s =0.chr                                                                                # No fill styles
123                 s+=2.chr                                                                                # Two line styles
124                 s+=packUI16(0) + 0.chr + 255.chr + 255.chr              # Width 5, RGB #00FFFF
125                 s+=packUI16(0) + 255.chr + 0.chr + 255.chr              # Width 5, RGB #FF00FF
126                 s+=34.chr                                                                               # 2 fill, 2 line index bits
127                 s
128         end
129         
130         def endShape
131                 '000000'
132         end
133         
134         def startAndMove(x,y,col)
135                 d='001001'                                                                              # Line style change, moveTo
136                 l =[lengthSB(x),lengthSB(y)].max
137                 d+=sprintf("%05b%0#{l}b%0#{l}b",l,x,y)
138                 d+=col                                                                                  # Select line style
139         end
140         
141         def drawTo(absx,absy,x,y)
142                 dx=x-absx
143                 dy=y-absy
144
145     # Split the line up if there's anything>16383, because
146     # that would overflow the 4 bits allowed for length
147     mstep=[dx.abs/16383,dy.abs/16383,1].max.ceil
148     xstep=dx/mstep
149     ystep=dy/mstep
150     d=''
151     for i in (1..mstep)
152       d+=drawSection(x,y,x+xstep,y+ystep)
153       x+=xstep
154       y+=ystep
155     end
156     d
157         end
158         
159         def drawSection(x1,y1,x2,y2)
160                 d='11'                                                                                  # TypeFlag, EdgeFlag
161           dx=x2-x1
162           dy=y2-y1
163                 l =[lengthSB(dx),lengthSB(dy)].max
164                 d+=sprintf("%04b",l-2)
165                 d+='1'                                                                                  # GeneralLine
166                 d+=sprintf("%0#{l}b%0#{l}b",dx,dy)
167   end
168
169         # -----------------------------------------------------------------------
170         # Specific data types
171
172   # SWF data block type
173
174         def swfRecord(id,r)
175                 if r.length>62
176       # Long header: tag id, 0x3F, length
177                         return packUI16((id<<6)+0x3F) + packUI32(r.length) + r
178                 else
179       # Short header: tag id, length
180                         return packUI16((id<<6)+r.length) + r
181                 end
182         end
183
184   # SWF RECT type
185
186         def packRect(a,b,c,d)
187                 l=[lengthSB(a),
188                    lengthSB(b),
189                    lengthSB(c),
190                    lengthSB(d)].max
191     # create binary string (00111001 etc.) - 5-byte length, then bbox
192                 n=sprintf("%05b%0#{l}b%0#{l}b%0#{l}b%0#{l}b",l,a,b,c,d)
193     # pack into byte string
194                 [n].pack("B*")
195         end
196
197         # -----------------------------------------------------------------------
198         # Generic pack functions
199         
200         def packUI16(n)
201                 [n.floor].pack("v")
202         end
203         
204         def packUI32(n)
205                 [n.floor].pack("V")
206         end
207         
208         # Find number of bits required to store arbitrary-length binary
209         
210         def lengthSB(n)
211                 Math.frexp(n+ (n==0?1:0) )[1]+1
212         end
213         
214         # ====================================================================
215         # Co-ordinate conversion
216         # (this is duplicated from amf_controller, should probably share)
217         
218         def lat2coord(a,basey,masterscale)
219                 -(lat2y(a)-basey)*masterscale
220         end
221         
222         def long2coord(a,baselong,masterscale)
223                 (a-baselong)*masterscale
224         end
225         
226         def lat2y(a)
227                 180/Math::PI * Math.log(Math.tan(Math::PI/4+a*(Math::PI/180)/2))
228         end
229
230         def sqlescape(a)
231                 a.gsub("'","''").gsub(92.chr,92.chr+92.chr)
232         end
233
234 end