Escape the Dungeon Overview
This group project presents a game-like social environment in Virtual Reality. The game starts inside a Dungeon which is guarded by a dragon, and requires two players two join the game. The main goal for the two players is to complete a series of missions and tasks by collaborating with each other and finally acquire the ability to beat the dragon in order to escape from the Dungeon.
Escape the Dungeon Collabrative Tasks
In general, there are 3 missions for the player to complete together in order to win the game. Before the player enter the game scene, there is an entrance lobby which allows users to join a game room or create a new room and invite their friends to join.
Fig.1 Screen captures of different collaborative tasks
Once the two players enter the game scene, each of them will be locked in two different rooms after they join the game. In each room, there is a number pad on the wall inside each room and several gold number bricks around the floor which serve as hints of the password of their teammate’s room. The two players must exchange the information through voice communication in order to solve the puzzle of each other’s room. The door will be unlocked only when the players click the 3 digit numbers in the correct order, and the information of the correct order of a room only exist in other room. So the task of this stage for players is to exchange information and solve the puzzle by collaborating through voice communication.
After the players leave their room successfully, they would need to complete the second collaborative task. As we all heard that dragons are greedy and addicted to collect shining jewels, the mission of the players is to collect all the four diamonds and put them into the chest. It will attract the dragon to open the only exit door. However, it is definitely not an easy work to collect the diamonds. Players are asked to overcome some traps and they need cooperate with each other to activate the triggers which are necessary to get those precious diamonds. Players cannot collect all diamonds without cooperation because it is necessary to ask another player for help in some triggers!
Finally, if the players successfully collect all the diamonds and put them into the chest, it’s time for our players to escape the dungeon! Unfortunately, the greedy dragon waiting behind the exit door seems ready for a big meal. With no chance to avoid the fight, our poor players know that their final task is to kill the dragon. They need to go back to the dungeon and find something to armour themselves. And there is a legendary sword stored in the depth of the dungeon which is surrounded by lava. Our players should use some tools from the surrounding environment to help themselves across the lava and get the sword. Because the poison on the surface of the sword is a huge threat to the dragon’s life, the players could then easily kill the dragon with the sword. After escaping from the dungeon, our players finally win the game.
Escape the Dungeon In-environment instructions
In order to let players get familiar with the game quick and have a clear awareness of the task at every stage, we set up word instructions to guide some key steps. Moreover, we try to use more visual and acoustic ways to guide players intuitively, such as using different eye-catching colour lights as hint in for some rooms and triggers, and include door-openning and various background sound when triggers activate remotely in order to let the users to have a more immersive game experience.
Escape the Dungeon implementations
1 Scene and Props
To start with, the scene was built with several packages from the asset store. For environment, we imported sky from Skybox Series Free, and also building templates from Decrepit Dungeon LITE. For better interaction, we imported 3D text from All Packages Demo, buttons from Interactive Physical Door Pack. We also imported some properties, such as treasure chest from Treasure Set, diamonds from Simple Gems Ultimate Animated Customizable Pack, dragon model from Dragon for Boss Monster : PBR, traps from Dungeon Traps, lava from Lava Flowing Shader and sword from Magic swords; arrows from Arrow Pointer. Then we modify those assets for our own variants. Figure below is the overview of the scene.
Fig.2 Scene
Our scene consists of two parts: internal environment and external environment. The internal environment is a dungeon, divided into upper and lower floors; the external environment consists of the dungeon’s exit and an entrance lobby for the player to enter the game scene.
2 Graspable Object
There are three kinds of objects that can be grasped in this game: diamonds, sword and boards. Diamonds are the target of second social task, sword is used to kill the dragon, and boards are used to go through traps.
At first, we use bulit-in function in GameObject to find Player via its name, and then compute the distance between Player and diamond. Players will only be able to grab diamonds if their distance is less than 5.0; otherwise players can get diamonds from far away instead of going through traps. Moreover, in the Update function of this script, we assign controller’s rotation and position to diamond in each frame, so the diamond Will move with the player’s grab. Remaining implementations of other two kinds of grasp objects are similar.
3 Trap
There are several kinds of traps: spike trap, cutter, swinging axe and lava on the ground. They are placed on the players’ only path to obtain diamonds. To get diamonds, players must cleverly find ways to pass through traps. Once the players trigger the trap, they are sent back to their original location and cannot obtain diamonds. To achieve this, we rewrite the function OnCollisionEnter to judge whether Player collides with traps. Figure below shows those traps.
Fig.3 Traps
Spike trap, cutter and swinging sway regularly, so it is necessary to find the law of their operation to avoid them. For lava on the ground, players need to find graspable boards and place them on lava to get through it. Tips on how to get through the lava are given to player 1, who informs player 2, and only player 2 needs to get through the lava.
4 Door Trigger
There are several kinds of door triggers: Number pad trigger, Step-on trigger and Chest trigger.
Number pad triggers: There are two doors that require players to click on the number pads which are placed on the wall in the two initial rooms. In each initial room, there is a 3 digit number clue hidden in the room. The 3 digit number is the hints of the password for the room where the player’s teammate located at. The two players must find the 3 digit number clue from the room and exchange that information with their teammate through voice communication in order to escape from their room. Once the player clicks the 3 numbers in the correct order, the door will open. To achieve this, we set the password in advance as a string form. Every time when we click the button, we append a string by adding the number we clicked, and then compare it to the password. If the string matched the password we initially set up, we rotate the door to be open.
Step-on triggers: The are two Step-on triggers that are placed next to two doors outside the room which contains diamonds. The upstairs doors will maintain open when the downstairs trigger are stepped on consistently by the other player, and so does the upstairs trigger work. Therefore, it is necessary for each player to collaborate with their partner to activate the step-on triggers in order to open the door and get the diamonds inside the room.
Chest triggers: The chest trigger opens the victory door that player could exit the dungeon. The exit door will open after all the 4 diamonds have been collected by the players and have been put into the chest. To implement it, we used a variable diamoundCount to record the number of diamonds that have been put into the chest(detected by collision). We also set a flag isCollected to check if the diamond has collided with the chest to prevent repeated scoring of a single diamond.
5 Synchronization of multiple scenes
Synchronization of different scenes means that the scene where each individual player in should be networked and synchronized. To be specific, any changes of the game objects in one player’s scene should also be faithfully reflected in all other players’ scene at the same time. Throughout experiment, we surprisingly found that in fact not all the game objects are needed to be networked and we have carefully chosen some critical game objects that are necessary to be synchronized in order to achieve the best performance.
There are 4 different types of game object that should be networked including diamonds, sword, wooden boards, and the doors with triggers to click. For the first 3 types of object, their position and rotation would be changed dynamically during game time since they would be carried around by the players. For the wooden doors with triggers, the rotation would change after one of the player clicks the corresponding trigger. In order to achieve synchronization between multiple scenes, the same object in each scene should be given with an identical id. For this reason, we have tried 3 different methods to obtain an unique id for those objects that are needed to be networked. A simple method is to manually set a specific value as the id of the object.
However, this naive approach could easily cause conflicts if a same id was accidentally given to two different game objects. To address this issue, we then tried to set the id based on the timestamp of the player once the program started.While this method could generate an unique id, another problem is that the id of the same object in different player’s scene could be very distinctive as the players may join the game room at a different time, and therefore this method is also discarded.
The final solution that we adopted is to combine the object’s position and rotation. As every object within the scene would have a distinctive position and rotation, this approach reduced the risk of having id conflict causing by the naive method, while still ensuring an unique id value could be given to the same object in different player’s scene regardless of the joining time the players. After setting up the id for the networked object, their position and rotation information would be updated between each other via Json message.
Escape the Dungeon Conclusion
Our group builds a well functioning and fully immersive Virtual Reality game that consists of different forms of highly collaborative tasks for players to complete in order to win the game. The users need to interact with different game objects within the VR environment such as collecting the diamonds and using the wooden board to pass through the lava, as well as clicking on the button in order to leave the locked room. Moreover, the scene of each players have been synchronized so that they share the same experience within the game. Furthermore, the game make use of various background sound in order to allow the users to enjoy a fully immersive game experience. Also, the visual style of the inside environment such as the weapons and decorations inside the dungeon, are designed to be consistent with the outside of the dungeon. We adopted a high quality skybox material to simulate the outer environment when the player exit the dungeon.