Hi,

I’ve a 3-D rectangular grid and I want to iterate over the grid working out the heat flows between all of the elements. I’ve currently got this as a grid and we using a Dim3 to iterate over each member and I calculate the heat loss between the six nearest neighbours and the central point. The downside of this is that I calculate the heat flow for each element twice and it would be great if a single block’s threads handled all of the grid positions near those of the other grid positions to limit the amount of fetching to each block. There’s also a lot of if statements to handle the edge conditions.

I’ve tried to work on a new system where each thread iterates along one direction in the block calculating the heat flows in the direction, with heat moving to grid location n+1 being equal to heat leaving grid location n. I then repeat this for each of the three directions.

In both cases I double-buffer the values so I write the values to a new array and then swap the pointers back at the end of the timestep.

I think this has got to be a fairly well studied problem on a GPU so I wanted to know if anyone else knew of the canonical way to solve this problem, running as fast as possible?

Thanks,