Balloo

Help Balloo! He lost all his coins and is stuck on a strange world. From the looks of it, his only way out is to fly away by collecting balloons. But where did they go?

Balloo is a third-person platform game. You control Balloo using your keyboard to move and mouse to aim. He can jump around and shoot fireballs. Beware of bad guys because they are mean! They will push you around. Get hit too many times, and you will lose. Jump on enemies or hit them with your fireball. Collect hearts, coins, and balloons to eventually escape!

In order to find the balloons, you must solve puzzles spread around the world. Pressing 'i' near a puzzle will give you a hint on how to solve it. There are 5 balloons in all. After collecting the balloons, defeat the boss and you win!

Advanced Features

• On-screen control panel and status screen - A game wouldn't be much fun without being able to see your status easily. You can see lots of information on the main screen, including HP, mana, and number of coins. You can also load a status screen.
• Bounding Volume Hierarchy - In order to speed up culling and collision detection, we organize all the objects in our world in a bounding volume hierarchy. This provides a spatial data structure that allows us to easily detect proximity between objects. Since our world is relatively flat (most objects are close to the ground), we use 2-D bounding volumes, i.e. circles.
• View frustum culling - To increase performance, we only draw objects inside the viewing frustum.
• LOD - We limit the number of vertices drawn depending on the size of the object.
• Procedural modelling - The mountains in the background are fractally-generated using a midpoint formula. All the trees are procedurally generated using a full-featured L-grammar system. As an example of the power of this system, we have six different types of trees (well, one is a fern, but close enough) that define themselves just with their productions. Fireballs are rendered with particle effects that generate particles with random locations and lifespans that follow the fireball and fade over time. To some extent, the character's animation is done procedurally. Every object essentially has a state machine and state counter. Based on these, the renderer alters the joints to show different actions.
• Collision Detection - We used a BVH for broad-phase collision detection. After checking the bounding volumes, narrow phase dectection is done with a more accurate collision algorithm. The narrow phase collision algorithm is also responsible for creating the collision contact that the physics engine uses.
• Simulated Dynamics - The game features a physics engine that is driven by forces and impulses. The physics engine interacts closely with the collision engine to acheive the correct physical response. Some responses are tweaked for smoother gameplay. Due to the nature of the game, there is no angular momentum/velocity. Objects do not rotate when hit; however, they do have a coefficient of restitution (to control bounciness) and a coefficient of friction. Triggered events are not scripted per se. Instead, an object is introduced into the world with an impulse.
• Advanced rendering effects - We used billboarding and particle effects to achieve more realistic looking fireballs.
• AI - Enemies will follow you after you attack them or after they see you. Once you leave their field of view they will go back to their normal behavior, but once you attack them once they'll follow you forever. If something is blocking their way, they will use pathfinding algorithms move around the obstacle. Since our world is rather sparse, implementing a full-featured A*-like search would be wasteful. Instead, we simply check for an object just in front and move around it in the closer direction. The little piggy also follows you to its mom! The birds in the sky move realistically using a flocking algorithm to simulate realistic behavior.
• Lights and light culling - There can be many light sources in the world. We use the BVH to perform light culling, so that each light source only lights things near it. Thus, having lots of lights doesn't have much of an effect on performance.

Screenshots

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Video

Download

• Download Windows executable