Page 168 - Hacking Roomba

Chapter 7 — Making RoombaView 149

Listing 7-7 Continued

status = “connected. safety fault. reposition roomba and
reset.”;
else
status = “connected. roomba detected. ok.”;
if( roombacomm != null ) {
batt_mA = roombacomm.current();
batt_volts = roombacomm.voltage();
batt_charge = roombacomm.charge();
batt_cap = roombacomm.capacity();
batt_percent = (batt_cap == 0) ? 0 :
(batt_charge*100)/batt_cap;
}
text(“ status: “+status, 8,12);
text(“ mode: “+((roombacomm==null)?”no roomba” :

roombacomm.modeAsString()), 8,24);
text(“battery: “+batt_percent+”%
(“+batt_charge+”/”+batt_cap+” mAh) “+
“ voltage: “+batt_volts+” mV @ “+batt_mA+”
mA”, 8,36);
}

Wrapping It All Up

With all the important functionality wrapped up in methods, the draw() method becomes
very simple. Listing 7-8 shows what it looks like. The only methods not covered were
drawGridlines(), which draws a simple grid on the background, and updateRoombaState(),
which only calls roombacomm.sensors(). The finished and running application is shown in
Figure 7-6. If you’d like to save the trouble of typing in all the code, the full sketch with already
exported applications can be found in the examples directory of the RoombaComm software
distribution. This is a fairly complex Processing application, but even so is only approximately
400 lines of code.

Listing 7-8: The draw() Method of RoombaView
void draw() {
background(cFlor);
drawGridlines();
drawStatus();
computeRoombaLocation();
drawRoombaStatus(rx,ry,rangle);
updateRoombaState();
}