lib/engine.lua

   1 -- Swamp Bike Opera embedded system for Kaffe Matthews
   2 -- Copyright (C) 2012 Wolfgang Hauptfleisch, Dave Griffiths
   3 --
   4 -- This program is free software: you can redistribute it and/or modify
   5 -- it under the terms of the GNU General Public License as published by
   6 -- the Free Software Foundation, either version 3 of the License, or
   7 -- (at your option) any later version.
   8 --
   9 -- This program is distributed in the hope that it will be useful,
  10 -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 -- GNU General Public License for more details.
  13 --
  14 -- You should have received a copy of the GNU General Public License
  15 -- along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 module("engine", package.seeall)
  18
  19 require 'gps'
  20 require 'posix'
  21 require 'poly'
  22 require 'map'
  23 require 'direction'
  24 require 'random'
  25 require 'audioc'
  26 require 'socket'
  27
  28 ----------------------------------------------------------------
  29 -- override for zones
  30
  31 overrides = {
  32 --   ["big"]={
  33 --      colour="blue",
  34 --      name="directional",
  35 --      dir="e",
  36 --   },
  37 }
  38
  39 ----------------------------------------------------------------
  40
  41 function gpslog(lat, lon)
  42    local  file = io.open(CONFIG.install_path.."log/gps.log", "a")
  43    local logmessage = os.date().." "..lat.." "..lon.."\n"
  44    file:write(logmessage)
  45    file:close()
  46 end
  47
  48 function log(logmessage)
  49    print(os.date().." "..logmessage)
  50 end
  51
  52 function say(txt)
  53     if txt~="" then
  54         print("saying:"..txt)
  55         --os.execute("espeak \""..txt.."\"")
  56     end
  57 end
  58
  59 ----------------------------------------------------------------
  60
  61 function read_events(events)
  62     local txt="";
  63
  64     for k,layer in pairs(events) do
  65         for k,event in pairs(layer) do
  66             txt=txt.." "..event.type.." ".." "..event.zone_colour.." "..
  67                      event.zone_name.." in "..event.layer_name.."."
  68         end
  69     end
  70     say(txt)
  71 end
  72
  73 ----------------------------------------------------------------
  74
  75 function dispatch_override(event,pos_state,override)
  76     if override.name=="directional" then
  77         play_directional(event,pos_state,override)
  78     end
  79 end
  80
  81 ----------------------------------------------------------------
  82
  83 function play_directional(event,pos_state,override)
  84     --utils.table_print(override)
  85
  86     --print(direction.pan_from(pos_state.dir,override.dir))
  87
  88     if event.type=="entered-zone" then
  89 --       print(direction.resolve(poly.angle(pos_state.dir)))
  90 --       utils.table_print(pos_state.dir)
  91 --       print(override.dir)
  92        audioc.loop(event.zone_name,
  93                    direction.pan_from(pos_state.dir,override.dir))
  94     end
  95     if event.type=="left-zone" then
  96        audioc.stop(event.zone_name)
  97     end
  98 end
  99
 100 --
 101 --          n
 102 --        nw ne
 103 --       w     e
 104 --        sw se
 105 --          s
 106 --
 107
 108 -- return true if facing in same direction (with 90 deg tolerance)
 109 -- this is stupid and dumb version
 110 function direction_compare(one,two)
 111     if (one == "n") then
 112        return utils.find_value(two,{"n","nw","n","ne","e"});
 113     end
 114     if (one == "ne") then
 115        return utils.find_value(two,{"nw","n","ne","e","se"});
 116     end
 117     if (one == "e") then
 118        return utils.find_value(two,{"n","ne","e","se","s"});
 119     end
 120     if (one == "se") then
 121        return utils.find_value(two,{"ne","e","se","s","sw"});
 122     end
 123     if (one == "s") then
 124        return utils.find_value(two,{"e","se","s","sw","w"});
 125     end
 126     if (one == "sw") then
 127        return utils.find_value(two,{"se","s","sw","w","nw"});
 128     end
 129     if (one == "w") then
 130        return utils.find_value(two,{"s","sw","w","nw","n"});
 131     end
 132     if (one == "nw") then
 133        return utils.find_value(two,{"sw","w","nw","n","ne"});
 134     end
 135     return false
 136 end
 137
 138
 139 function cats_to_direction(parent,cats)
 140     if (utils.find_value(parent..":North",cats)) then
 141         if (utils.find_value(parent..":East",cats)) then
 142             return "ne"
 143         end
 144         if (utils.find_value(parent..":West",cats)) then
 145             return "nw"
 146         end
 147         return "n"
 148     end
 149     if (utils.find_value(parent..":South",cats)) then
 150         if (utils.find_value(parent..":East",cats)) then
 151             return "se"
 152         end
 153         if (utils.find_value(parent..":West",cats)) then
 154             return "sw"
 155         end
 156         return "s"
 157     end
 158     if (utils.find_value(parent..":West",cats)) then
 159         return "w"
 160     end
 161     if (utils.find_value(parent..":East",cats)) then
 162         return "e"
 163     end
 164     return "centre";
 165 end
 166
 167 ----------------------------------------------------------------
 168 -- not sure this is the best place for this!
 169 local panned_samples={}
 170 local one_shot_samples={}
 171
 172 function play_events(events,pos_state)
 173
 174     -- first if the direction has been updated, go through
 175     -- all the panned samples
 176     if pos_state.new_direction then
 177         print("updating direction")
 178         for name,dir in pairs(panned_samples) do
 179             local pan=direction.pan_from(pos_state.dir,dir)
 180             print("shifting "..name.." to "..pan)
 181             audioc.shift(name,pan)
 182         end
 183     end
 184
 185     -- now look through all the maps for new events
 186     for k,layer in pairs(events) do
 187         for k,event in pairs(layer) do
 188             engine.log(event.type.." "..event.zone_name.." in "..event.layer_name)
 189
 190             local switch_dir = cats_to_direction("Direction Parameter",event.zone_categories)
 191             local heading = direction.resolve(poly.angle(pos_state.dir))
 192
 193             if (switch_dir~="centre") then
 194                 -- if this zone is using a direction to switch, check here
 195                 print("DIRECTIONAL--->"..switch_dir.." vs current "..heading)
 196                 if (direction_compare(switch_dir,heading)) then
 197                     print "ACCEPTED"
 198                 else
 199                     print "wrong way"
 200                 end
 201             end
 202
 203             if switch_dir=="centre" or direction_compare(switch_dir,heading) then
 204                 -- defaults
 205                 local name=event.zone_name
 206                 local loop="no"
 207                 if (utils.find_value("Sample Parameters:Loop",event.zone_categories)) then
 208                    loop="yes"
 209                 end
 210                 local dir=cats_to_direction("Pan Parameter",event.zone_categories)
 211
 212         -- is it a one shot sample?
 213                 if (utils.find_value("Sample Parameters:One shot",event.zone_categories)) then
 214             one_shot_samples[name]="yes"
 215         end
 216
 217                 -- look for an override
 218                 local override=overrides[event.zone_name]
 219                 if override then
 220                    dispatch_override(event,pos_state,override)
 221                 else
 222                     -- default behaviour
 223                     if event.type=="entered-zone" then
 224                        if dir=="centre" then ----- normal -------
 225                            if loop=="no" then
 226                                audioc.play(name)
 227                            else
 228                                audioc.loop(name)
 229                            end
 230                        else ------- directional ---------------
 231                            -- add to panned samples so we can update it later
 232                            panned_samples[name]=dir
 233                            print("added panned "..name.." "..dir)
 234                            local pan=direction.pan_from(pos_state.dir,dir)
 235                            if loop=="no" then
 236                                audioc.play(name,pan)
 237                            else
 238                                audioc.loop(name,pan)
 239                            end
 240                        end
 241                     end
 242                 end
 243
 244                 if event.type=="left-zone" then
 245                     if panned_samples[name] then
 246                         panned_samples[name]=nil
 247                     end
 248
 249                 if one_shot_samples[name]~="yes" then
 250                     audioc.fadeout(name)
 251                 end
 252                 end
 253             end
 254         end
 255     end
 256 end
 257
 258 ----------------------------------------------------------------------
 259
 260 function update_pos_state(pos,state)
 261     -- calculate distance since last time
 262     local time_diff = os.time() - state.time
 263
 264     state.new_direction=false
 265
 266     if time_diff > CONFIG.direction_track_time then
 267         state.time = os.time()
 268         if state.pos then
 269             local distance=poly.distance_km(pos.lat, pos.lng,
 270                                             state.pos.lat, state.pos.lng);
 271             state.speed=distance/CONFIG.direction_track_time;
 272             state.dir={lat=pos.lat-state.pos.lat,
 273                        lng=pos.lng-state.pos.lng}
 274         end
 275         state.pos = pos
 276         state.new_direction=true
 277
 278         log("speed is "..state.speed.."km/h"..
 279             " direction is "..direction.resolve(poly.angle(state.dir)))
 280     end
 281     return state
 282 end
 283
 284 ----------------------------------------------------------------
 285
 286 function load_events(events,pos_state)
 287     for k,layer in pairs(events) do
 288         for k,event in pairs(layer) do
 289             engine.log("load event: "..event.type.." "..event.zone_name.." in "..event.layer_name)
 290
 291             -- zone name consists of:
 292             -- <name>_<loop>_<direction>_<ghost>
 293             local tokens=std.split(event.zone_name,"_")
 294
 295             -- defaults
 296             local name=tokens[1]
 297
 298             -- default behaviour
 299             if event.type=="entered-zone" then
 300                 audioc.load(name)
 301             end
 302             if event.type=="left-zone" then
 303                 audioc.unload(name)
 304             end
 305         end
 306     end
 307 end