private Flow CalculateFlowAt(int x, int y)
{
Flow result = new Flow();
for (int i=0; i<3; i++) {
for (int j=0; j<3; j++) {
int xd = i + x - 1;
int yd = j + y - 1;
if (field.Validate (xd, yd)) {
if (SurfaceLevel (x, y) > SurfaceLevel (xd, yd) + maxDelta) {
int delta = SurfaceLevel (x, y) - SurfaceLevel (xd, yd);
result.flowDirection [i, j] = delta;
result.flowAmount = Math.Max (result.flowAmount, delta);
}
}
}
}
return result;
}
private bool PerformFlow()
{
bool result = false;
Flow[,] flows = new Flow[xSize, ySize];
// calculating where the water will flow
for (int x=0; x<xSize; x++) {
for (int y=0; y<ySize; y++) {
if (values [x, y] > 0) {
flows [x, y] = CalculateFlowAt (x, y);
}
}
}
// performing the water flow
for (int x=0; x<xSize; x++) {
for (int y=0; y<ySize; y++) {
if (values [x, y] > 0) {
result = result || PerformFlowAt (x, y, flows [x, y]);
}
}
}
return result;
}
private bool PerformFlowAt(int x, int y, Flow flow)
{
bool result = false;
int [,] normalizedFlow = flow.NormalizedFlow();
for (int i=0; i<3; i++) {
for (int j=0; j<3; j++) {
int xd = i + x - 1;
int yd = j + y - 1;
int flowThere = normalizedFlow [i, j];
if (flowThere > 0) {
result = true;
values [xd, yd] += flowThere;
values [x, y] -= flowThere;
}
}
}
return result;
}