public void Execute(int workItemIndex)
{
int start, end;
batchData.GetConstraintRange(workItemIndex, out start, out end);
for (int i = start; i < end; ++i)
{
var pair = pairs[i];
float4 distanceA = renderablePositions[pair.particleB] - smoothPositions[pair.particleA];
float4 distanceB = renderablePositions[pair.particleA] - smoothPositions[pair.particleB];
anisotropies[pair.particleA] += BurstMath.multrnsp(distanceA, distanceA) * pair.avgKernel;
anisotropies[pair.particleB] += BurstMath.multrnsp(distanceB, distanceB) * pair.avgKernel;
}
}