Add new feature: Tunnel Paring

[bgh716]

Expected Behavior

• Pair Tunnel entrance/exit
  • Pairing info is stored in global variable which also holds extra objects for the tunnel
  • When a train enters entrance, a ghost car is generated to the direction of the exit(with angle calculated from entrance/exit coordinates)
  • When ghost car 'hits' the exit train starts to leave the tunnel
  • Discard ghost car, and use dis = time x vel
• Automate Tunnel Placement
  • When a player places the entrance with the entrance placer, generate exit placer on cursor so the player can place entrance/exit without need to hold two items in inventory
    • use player.cursor_stack.set_stack(stuff)
  • When a player places the entrance with the entrance placer, generate blue print containing entrance placer and two train signals on mouse cursor
  • Exit placer should be deleted upon canceling(pressing q), not returning to inventory to prevent dup
  • When player cancels placing exit
  • Entrance is also destroyed, returning to inventory
  • or entrance remains, and when player clicks unpaired entrance exit placer is generated on cursor(as if player built the entrance)
    • Could use [LuaPlayer.clear_cursor], [LuaPlayer.cursor_stack-temporary]
    • Could use custom input to get clear cursor event and check [custom input]
• Destroying Paired Tunnels
  • destroying one of the paired tunels also removes the other, returning entrance placer to inventory

Extra goals

• Physically block train at end of the tunnel to prevent train entering from reverse direction
• Visualize tunnel connectivity
  • When clicking one of paired tunnels, draw a line between connected tunnels
  • player should be able to see tunnel connections through API button(buttons at right-bottom), or clicking a paired tunnel
• Limit tunnel connection distance
  • check the distance between entrance/exit when exit is built, and cancel when the distance is too far(ex. more than a screen away)

[bgh716]

~permanent TempTrain for entrance~

• need pairing feature to be implemented, since both need global TrainTunnel array to hold extra objects(paired tunnel, auto-placed signals, temporary train, etc..) for each tunnel
• should be moved to separated issue

[bgh716]

~signal automation~

• need pairing feature to be implemented, since both need global TrainTunnel array to hold extra objects(paired tunnel, auto-placed signals, temporary train, etc..) for each tunnel
• should be moved to separated issue

[bgh716]

~prevent reverse entering~

• moved to another comment

[bgh716]

Feature Implemented2.0

• Pair Tunnel entrance/exit
  • Pairing info is stored in global variable which also holds extra objects for the tunnel
  • When a train enters entrance, a ghost car is generated to the direction of the exit(with angle calculated from entrance/exit coordinates)
  • When ghost car 'hits' the exit train starts to leave the tunnel
• Automate Tunnel Placement
  • When a player places the entrance with the entrance placer, generate exit placer on cursor so the player can place entrance/exit without need to hold two items in inventory
  • When a player places the entrance with the entrance placer, generate entrance placer and two train signals
  • Exit placer should be deleted upon canceling(pressing q), not returning to inventory to prevent dup
  • When player cancels placing exit
  • Entrance can be paired with SHIFT+Z key again
• Destroying Paired Tunnels
  • destroying Entrance destroy Exit, but destroying Exit does not destroy Entrance
• Only entered carriages go out to exit
• If tunnel is destroyed while train is in the tunnel, train is removed(user lose items in carriage)
• Carriages are boosted as front rolling stock hits the tunnel
• Destroying tunnel destroy all its components(tunnel, wall, garage, signals)
• Physically block train at end of the tunnel to prevent train entering from reverse direction

Maybe for future

• Destroyed train in the tunnel makes a box to have items that were in the carriages
• Visualize tunnel connectivity
  • When clicking one of paired tunnels, draw a line between connected tunnels
  • player should be able to see tunnel connections through API button(buttons at right-bottom), or clicking a paired tunnel
• Limit tunnel connection distance
  • check the distance between entrance/exit when exit is built, and cancel when the distance is too far(ex. more than a screen away) => there is distance key for paired tunnel

[bgh716]

only left todo

-Limit tunnel connection distance check the distance between entrance/exit when exit is built, and cancel when the distance is too far(ex. more than a screen away) => there is distance key for paired tunnel