Penguinvania is a four players party game using PSMove created in our 6 people team in BVW Round 5. The player controls a penguin, sliding on the ice and collecting fish to win by the highest scores. This game is for BVW Festival, so it need to amuse both players and audience. To achieve this, we focus on the Game Experience during developing. We follow a principle, “The highest-frequency interactions and elements should get the most polish.” Specifically, we polish our world from three aspects: control, physical rules, feedback.
For Penguinvania, the most frequent input is controlling the penguin using PSMove. Pressing the trigger on PSMove to increase speed is intuitive for most people. However, how to control the penguins direction smoothly is tricky.
Solution 1: Originally, we use PSMove’s direction of X and Z (horizontal plane) which matches the ice island in the game. For example, when pointing PSMove to the forward, the penguin heads to further island (top of the screen). But the problem is that it is very hard for some players pointed backward if they want their penguins move down at the screen. Then we change to use PSMove’s direction of X and Y (vertical plane) which matches the screen. The same problem appears when players try to move down.
We realize that the problem here is that the limitation of human’s twists.
Solution 2: We use PSMove as a pointer controlling a cursor on the screen. The penguin will move to the cursor. This fixes the direction problem but there will be 4 penguins and 4 cursors move around the screen. It is so noisy that diminish the aesthetics. If hide the cursor, the player lose the feeling of the direction.
To sum up, we need to fix two problems on direction control: 1. physically easy control; 2. mentally easy perception. Based on that, we propose an perfect solution 3.
Solution 3: We project PSMove’s direction on the horizontal plane. So players can hold the PSMove and tilt it slightly to control the direction. To strengthen the perception of the direction.
Moreover, we add a halo with arrow to show the current direction of the penguin. With this control method, players can easily adjust the penguin’s direction and observe the current direction instantly.
At the beginning, we use natural physical rules to simulate penguins movement and bumping on the ground. However, we find the following experience:
- Penguins slide into the water because it is hard to slow down (friction is too small);
- Penguins start up too slow because friction is too large;
- Collisions do not have a enough impact because there is energy lost during elastic collision;
Because problem 1 & 2 are contradict in physical rules (change friction in different directions) so we use some additive rules on it. The force added on a penguin when pressing trigger will be corresponding to penguin’s speed. The faster, the lower. So the penguin will speed up more quickly at the beginning and have a limited highest speed.
And we add an extra opposite force when releasing the trigger to help slow down the penguin.
Collision is the most important moment of our game so we need to strengthen it. We preserve elastic collision but make penguins follow the Momentum Theorem which should be followed in non-elastic collision. Then collisions become more violent.
Then we move on polishing feedback to make the experience more exciting. There are two kinds of important moments in the game: 1. collecting fish; 2. collision with others. The second is more important because it is an interactive moment.
For collecting fish, we give feedback from:
- sound effects; (if you collect a precious golden fish. Sound effects will be more obvious)
- popping points;
- collecting animation. (in progress)
For collision, there will be:
- a strong sound effect;
- a blast of fish out of penguins baskets;
- an obvious force and sliding. (penguins will lose control for half a second after collision)
- dizzy animation. (in progress).
Also, for different kinds of props you can collect during the game. They will give an icon and timer to show who activate it. And some of them have a special VFX.
Game design, maintain design documents, gameplay programming, UI design.