Dijkstra’s shortest path algorithm
Properties
•It
computes the minimum cost path from the seed to every node
in the graph. This set of minimum paths
is represented as a tree
•Running
time, with N pixels:
–O(N2)
time if you use an active list
–O(N
log N) if you use an active priority queue (heap)
–takes
< second for a typical (640x480) image
•Once
this tree is computed once, we can extract the optimal path
from any point to the seed in O(N/2) time.
–it
runs in real time as the mouse moves
•What
happens when the user specifies a new seed?