Interactive Lego World

Major technologies in use:

• Hierarchical modeling
• Used in the rendering/modeling of the Lego people
• Each piece within the hierarchy can have 'joints' which impact all children within the model



• State-based animations/behaviors
• The two types of entities which make use of states are:
  1. Lego people
  • Each joint allows for rotations back and forth between a custom angle range
  • A range of behavior states: Alone at home, Following the player, Running away, Opening/Closing the door
  • The following image shows the flowchart for the simplest state: IDLE

  

  2. Doors
     • State-based animations: Opened, Opening, Closed, Closing
• Collision detection (technically)
• The ultimate purpose of the collision detection in this project is to assist in transitioning between states for the state-based entities.
• Examples of collisions detected:
  • The player and the Lego people
  • The Lego people and buildings
  • The player and buildings
• Pathfinding
• Used to find the general route a Lego person should follow to get 'close' to their desired goal.

External libraries:

• GLFW
• GLAD
• GLM
• tiny_obj_loader

External resources:

Lego Digital Designer (LDD):

• This is a tool created by Lego which provides a way to design Lego builds.
• Contains a digital representation of nearly every realworld Lego block

Types of non-source files:

I wanted to make this project as dynamic as possible, so I wrote several filetype parsers to allow as much data as possible to not be hard-coded. The types of data files I ended up with are:

• Mesh files:
• Contains model information
• I wrote a wrapper to the tiny_obj_loader provided in class allowing for a wider range of obj files to be used.
• Material file (not the Wavefront material files):
• Contains a collection of materials that can be used by any mesh
• World file:
• Created using the LDD.
• Originally contained information on brick locations and groupings.
• I wrote a parser for this type of file which treats certain brick types as markers for path-map vertices.
• The following image shows the world as rendered by the LDD

Reflections:

My initial proposition for this project was far more grandiose than what I actually achieved. However, the complexity of what went into the current state of the project far surpasses what I had estimated for the entirety of my initial proposal. The amount of work it takes to model a real-time, dynamic, 'slightly believable' interaction between objects is far greater than I had initially thought. I'm very excited to have spent so much time working on the state-based animations and behaviors of the Lego people.