internal void Remove(ref Int2 index, Grid2DEntry entry) { int cellIndex; int sortingHash; if (TryGetIndex(ref index, out cellIndex, out sortingHash)) { cells.Elements[cellIndex].Remove(entry); if (cells.Elements[cellIndex].entries.count == 0) { //The cell is now empty. Give it back to the pool. var toRemove = cells.Elements[cellIndex]; //There's no cleanup to do on the grid cell. //Its list is empty, and the rest is just value types. cells.RemoveAt(cellIndex); cellPool.GiveBack(toRemove); count--; } } //int sortingHash = index.GetSortingHash(); //int minIndex = 0; //inclusive //int maxIndex = count; //exclusive //int i = 0; //while (maxIndex - minIndex > 0) //If the testing interval has a length of zero, we've done as much as we can. //{ // i = (maxIndex + minIndex) / 2; // if (cells.Elements[i].sortingHash > sortingHash) // maxIndex = i; // else if (cells.Elements[i].sortingHash < sortingHash) // minIndex = ++i; // else // { // //Found an equal sorting hash! // //The hash can collide, and we cannot add an entry to // //an incorrect index. It would break the 'cell responsibility' // //used by the cell update process to avoid duplicate overlaps. // //So, check if the index we found is ACTUALLY correct. // if (cells.Elements[i].cellIndex.Y == index.Y && cells.Elements[i].cellIndex.Z == index.Z) // { // cells.Elements[i].Remove(entry); // if (cells.Elements[i].entries.count == 0) // { // //The cell is now empty. Give it back to the pool. // var toRemove = cells.Elements[i]; // //There's no cleanup to do on the grid cell. // //Its list is empty, and the rest is just value types. // cells.RemoveAt(i); // cellPool.GiveBack(toRemove); // count--; // } // return; // } // //If it was not the correct index, let it continue searching. // } //} ////Getting here should be impossible. }
internal void Add(ref Int2 index, Grid2DEntry entry) { int cellIndex; int sortingHash; if (TryGetIndex(ref index, out cellIndex, out sortingHash)) { cells.Elements[cellIndex].Add(entry); return; } var cell = cellPool.Take(); cell.Initialize(ref index, sortingHash); cell.Add(entry); cells.Insert(cellIndex, cell); count++; return; ////Take an index. See if it's taken in the set. ////If it's already there, then add the entry to the cell. ////If it's not already there, create a new cell and add the entry to the cell and insert it at the index located. //int sortingHash = index.GetSortingHash(); //int minIndex = 0; //inclusive //int maxIndex = count; //exclusive //int i = 0; //while (maxIndex - minIndex > 0) //If the testing interval has a length of zero, we've done as much as we can. //{ // i = (maxIndex + minIndex) / 2; // if (cells.Elements[i].sortingHash > sortingHash) // maxIndex = i; // else if (cells.Elements[i].sortingHash < sortingHash) // minIndex = ++i; // else // { // //Found an equal sorting hash! // //The hash can collide, and we cannot add an entry to // //an incorrect index. It would break the 'cell responsibility' // //used by the cell update process to avoid duplicate overlaps. // //So, check if the index we found is ACTUALLY correct. // if (cells.Elements[i].cellIndex.Y == index.Y && cells.Elements[i].cellIndex.Z == index.Z) // { // cells.Elements[i].Add(entry); // return; // } // //If it was not the correct index, let it continue searching. // } //} //var cell = cellPool.Take(); //cell.Initialize(ref index, sortingHash); //cell.Add(entry); //cells.Insert(i, cell); //count++; }
internal void Remove(Grid2DEntry entry) { entries.Remove(entry); }
internal void Add(Grid2DEntry entry) { //binary search for the approximately correct location. This helps prevent large first-frame sort times. entries.Insert(GetIndex(entry.item.boundingBox.Min.X), entry); }
internal void UpdateOverlaps(Grid2DSortAndSweep owner) { //Sort along x axis using insertion sort; the list will be nearly sorted, so very few swaps are necessary. for (int i = 1; i < entries.count; i++) { var entry = entries.Elements[i]; for (int j = i - 1; j >= 0; j--) { if (entry.item.boundingBox.Min.X < entries.Elements[j].item.boundingBox.Min.X) { entries.Elements[j + 1] = entries.Elements[j]; entries.Elements[j] = entry; } else { break; } } } //Sweep the list looking for overlaps. for (int i = 0; i < entries.count; i++) { Grid2DEntry a = entries.Elements[i]; Grid2DEntry b; //TODO: Microoptimize for (int j = i + 1; j < entries.count && a.item.boundingBox.Max.X >= (b = entries.Elements[j]).item.boundingBox.Min.X; j++) { if (!(a.item.boundingBox.Min.Y > b.item.boundingBox.Max.Y || a.item.boundingBox.Max.Y < b.item.boundingBox.Min.Y || a.item.boundingBox.Min.Z > b.item.boundingBox.Max.Z || a.item.boundingBox.Max.Z < b.item.boundingBox.Min.Z)) { //Now we know this pair is overlapping, but we do not know if this overlap is already added. //Rather than use a hashset or other heavy structure to check, rely on the rules of the grid. //It's possible to avoid adding pairs entirely unless we are the designated 'responsible' cell. //All other cells will defer to the cell 'responsible' for a pair. //A simple rule for determining the cell which is responsible is to choose the cell which is the //smallest index in the shared cells. So first, compute that cell's index. Int2 minimumSharedIndex = a.previousMin; if (minimumSharedIndex.Y < b.previousMin.Y) { minimumSharedIndex.Y = b.previousMin.Y; } if (minimumSharedIndex.Y > b.previousMax.Y) { minimumSharedIndex.Y = b.previousMax.Y; } if (minimumSharedIndex.Z < b.previousMin.Z) { minimumSharedIndex.Z = b.previousMin.Z; } if (minimumSharedIndex.Z > b.previousMax.Z) { minimumSharedIndex.Z = b.previousMax.Z; } //Is our cell the minimum cell? if (minimumSharedIndex.Y == cellIndex.Y && minimumSharedIndex.Z == cellIndex.Z) { owner.TryToAddOverlap(a.item, b.item); } } } } }
internal void Remove(ref Int2 index, Grid2DEntry entry) { int cellIndex; int sortingHash; if (TryGetIndex(ref index, out cellIndex, out sortingHash)) { cells.Elements[cellIndex].Remove(entry); if (cells.Elements[cellIndex].entries.Count == 0) { //The cell is now empty. Give it back to the pool. var toRemove = cells.Elements[cellIndex]; //There's no cleanup to do on the grid cell. //Its list is empty, and the rest is just value types. cells.RemoveAt(cellIndex); cellPool.GiveBack(toRemove); count--; } } //int sortingHash = index.GetSortingHash(); //int minIndex = 0; //inclusive //int maxIndex = count; //exclusive //int i = 0; //while (maxIndex - minIndex > 0) //If the testing interval has a length of zero, we've done as much as we can. //{ // i = (maxIndex + minIndex) / 2; // if (cells.Elements[i].sortingHash > sortingHash) // maxIndex = i; // else if (cells.Elements[i].sortingHash < sortingHash) // minIndex = ++i; // else // { // //Found an equal sorting hash! // //The hash can collide, and we cannot add an entry to // //an incorrect index. It would break the 'cell responsibility' // //used by the cell update process to avoid duplicate overlaps. // //So, check if the index we found is ACTUALLY correct. // if (cells.Elements[i].cellIndex.Y == index.Y && cells.Elements[i].cellIndex.Z == index.Z) // { // cells.Elements[i].Remove(entry); // if (cells.Elements[i].entries.count == 0) // { // //The cell is now empty. Give it back to the pool. // var toRemove = cells.Elements[i]; // //There's no cleanup to do on the grid cell. // //Its list is empty, and the rest is just value types. // cells.RemoveAt(i); // cellPool.GiveBack(toRemove); // count--; // } // return; // } // //If it was not the correct index, let it continue searching. // } //} ////Getting here should be impossible. }