A star with Multiple objects path finding

1. Created a square grid 20x20 nodes in size.

• Randomly (and via the mouse) marked some of the nodes as "impassable or blocked".

• Allowed each grid node to have a variable cost, via the mouse, 3 variations. For example, road tiles cost 1, forest tiles cost 2, water tiles cost 3.

• Visualized the grid.

2. Created 10 game entities that navigate the grid in real-time.

• Each entity chooses a random goal grid node as it's destination, perform an A* pathfind to that goal, and then travels along the calculated path to reach the goal. Each node's cost is accounted when path finding.

• Each entity performs "seek"-like steering for the intermediate nodes along the path, and "arrival"-like steering for the goal node.

• After each entity arrives (stops at) it's goal, it randomly chooses a new goal and keep going.

• Allowed one entity to be "marked", to single it out for visualization. Visualized the 'start' and 'goal' nodes, it's current calculated path, and it's steering vector.

Start Node:

Goal Node:

Impassable Node:

Normal Node:

Forest Node: (Cost is 5, greater than normal node)

Water Node: (Cost is 10, greater than forest and normal node)

Hover Car: Uses A star algorithm to find the path to a next goal node in the scene randomly and performs seek / Arrive. The tile cost is taken in account when trying to find the path. Nodes with higher costs are avoided as much as possible. Preference is given in order,

Normal Node > Forest Node > Water Node

A * Algorithm used:

Heuristics will make the frontier expand towards the goal more than it expands in other directions.

Game Build

Source Code (Unity3D)