1. Coral Growth via Nutrient Random Walk
By Steve Shen

2. Assumptions
Method
Coastal marine organism dependent on nutrients and sunlight
Nutrients diffuse in system via random walk.
Coral polyp grows when it has received a certain amount of nutrients.
Polyps have a tendency to grow in the direction of the nutrients
Only polyps on the surface participate.
Coral can grow at all depths of the system. 2D
For nParticles
while 1
nutrients diffuse w/o PBC
if neighbor has coral, stop diffusion and add nutrients to cell.
break from while loop
Check coral cell that stopped the diffusion
if sum of nutrients around that cell > threshold, grow a coral
new image
end

3. Run with FinalCoralGrowth.m

4. Comparison with Standard DLA
No PBC More aggressive branching
Self-directed ‘flow’ behavior
‘Fixed’;
% Starting point of nutrient diffusion
x = 3+floor((maxX-2)*rand);
Demonstrates aggressive sensitivity to small changes
% Starting point of nutrient diffusion
x = 3+floor((maxX)*rand);