コード例 #1
0
ファイル: VoxelAStar.cs プロジェクト: morgash1989/Lemma
        public static void Narrowphase(Voxel m, Voxel.Coord start, Voxel.Box target, Stack <Voxel.Coord> result)
        {
            Voxel.Box        currentBox = m.GetBox(start);
            Vector3          targetPos  = target.GetCenter();
            NarrowphaseEntry startEntry = new NarrowphaseEntry
            {
                Parent = null,
                Coord  = start,
                G      = 0,
                F      = (targetPos - m.GetRelativePosition(start)).Length(),
            };

            narrowphaseQueue.Push(startEntry);
            narrowphaseQueueLookup[start] = startEntry;

            NarrowphaseEntry closestEntry     = null;
            float            closestHeuristic = float.MaxValue;

            int iterations = 0;

            while (narrowphaseQueue.Count > 0 && iterations < 80)
            {
                iterations++;

                NarrowphaseEntry entry = narrowphaseQueue.Pop();

                if (m.GetBox(entry.Coord) == target)
                {
                    closestEntry = entry;
                    break;
                }

                narrowphaseQueueLookup.Remove(entry.Coord);

                narrowphaseClosed[entry.Coord] = entry.G;
                for (int i = 0; i < 6; i++)
                {
                    Voxel.Coord adjacent = entry.Coord.Move(DirectionExtensions.Directions[i]);
                    if (!currentBox.Contains(adjacent) && !target.Contains(adjacent))
                    {
                        continue;
                    }

                    int tentativeGScore = entry.G + 1;

                    int  previousGScore;
                    bool hasPreviousGScore = narrowphaseClosed.TryGetValue(adjacent, out previousGScore);

                    if (hasPreviousGScore && tentativeGScore > previousGScore)
                    {
                        continue;
                    }

                    NarrowphaseEntry alreadyInQueue;
                    narrowphaseQueueLookup.TryGetValue(adjacent, out alreadyInQueue);

                    if (alreadyInQueue == null || tentativeGScore < previousGScore)
                    {
                        NarrowphaseEntry newEntry = alreadyInQueue != null ? alreadyInQueue : new NarrowphaseEntry();

                        newEntry.Parent = entry;
                        newEntry.G      = tentativeGScore;
                        float heuristic = (targetPos - m.GetRelativePosition(adjacent)).Length();
                        newEntry.F = tentativeGScore + heuristic;

                        if (heuristic < closestHeuristic)
                        {
                            closestEntry     = newEntry;
                            closestHeuristic = heuristic;
                        }

                        if (alreadyInQueue == null)
                        {
                            newEntry.Coord = adjacent;
                            narrowphaseQueue.Push(newEntry);
                            narrowphaseQueueLookup[adjacent] = newEntry;
                        }
                    }
                }
            }
            narrowphaseClosed.Clear();
            narrowphaseQueue.Clear();
            narrowphaseQueueLookup.Clear();
            if (closestEntry != null)
            {
                VoxelAStar.reconstructNarrowphasePath(closestEntry, result);
            }
        }