public static void Process(CoordRect rect, Chunk.Results results, GeneratorsAsset gens, Chunk.Size terrainSize, Func <float, bool> stop = null)
        {
                        #if VEGETATION_STUDIO
            if (stop != null && stop(0))
            {
                return;
            }

            //preparing and clearing storage
            if (vetStorComponents == null || vetStorComponents.Count == 0)
            {
                return;                                                                        //vs not used (process runs anyway)
            }
            PersistentVegetationStorage storage = vetStorComponents[rect];

            int cellXCount = Mathf.CeilToInt(terrainSize.dimensions / cellSize);
            int cellZCount = Mathf.CeilToInt(terrainSize.dimensions / cellSize);

            Noise noise = new Noise(12345, permutationCount: 128);            //to pick objects based on biome


            //clearing all of the items
            foreach (VegetationStudioOutput gen in gens.GeneratorsOfType <VegetationStudioOutput>(onlyEnabled:true, checkBiomes:true))
            {
                for (int b = 0; b < gen.layers.Length; b++)
                {
                    string id = gen.package.VegetationInfoList[b].VegetationItemID;
                    storage.RemoveVegetationItemInstances(id, VS_MM_id);
                }
                break;                 //iterating in one generator only - they use the same layers
            }

            if (stop != null && stop(0))
            {
                return;
            }

            //object outputs
            foreach (VegetationStudioOutput gen in gens.GeneratorsOfType <VegetationStudioOutput>(onlyEnabled:true, checkBiomes:true))
            {
                //gen biome mask
                Matrix biomeMask = null;
                if (gen.biome != null)
                {
                    object biomeMaskObj = gen.biome.mask.GetObject(results);
                    if (biomeMaskObj == null)
                    {
                        continue;                                           //adding nothing if biome has no mask
                    }
                    biomeMask = (Matrix)biomeMaskObj;
                    if (biomeMask == null)
                    {
                        continue;
                    }
                    if (biomeMask.IsEmpty())
                    {
                        continue;                                          //optimizing empty biomes
                    }
                }

                //iterating in layers
                for (int b = 0; b < gen.layers.Length; b++)
                {
                    if (stop != null && stop(0))
                    {
                        return;                                            //checking stop before reading output
                    }
                    Layer layer = gen.layers[b];

                    string id = gen.package.VegetationInfoList[b].VegetationItemID;


                    //objects layer
                    if (layer.type == Layer.Type.Object)
                    {
                        //loading objects from input
                        SpatialHash hash = (SpatialHash)gen.layers[b].objInput.GetObject(results);
                        if (hash == null)
                        {
                            continue;
                        }

                        //filling instances (no need to check/add key in multidict)
                        foreach (SpatialObject obj in hash.AllObjs())
                        {
                            //skipping on biome not used
                            float biomeFactor = 0;
                            if (gen.biome == null)
                            {
                                biomeFactor = 1;
                            }
                            else if (biomeMask != null)
                            {
                                biomeFactor = biomeMask.GetInterpolated(obj.pos.x, obj.pos.y);
                            }
                            if (biomeFactor < 0.00001f)
                            {
                                continue;
                            }

                            float rnd;
                            switch (biomeBlendType)
                            {
                            case ObjectOutput.BiomeBlendType.Sharp: rnd = 0.5f; break;

                            case ObjectOutput.BiomeBlendType.AdditiveRandom:
                            case ObjectOutput.BiomeBlendType.NormalizedRandom:
                                rnd = noise.Random((int)obj.pos.x, (int)obj.pos.y);
                                if (biomeFactor > 0.5f)
                                {
                                    rnd = 1 - rnd;                                                           //test
                                }
                                break;

                            case ObjectOutput.BiomeBlendType.Scale: rnd = 0.0f; break;

                            default: rnd = 0.5f; break;
                            }

                            if (biomeFactor < rnd)
                            {
                                continue;
                            }

                            //flooring
                            float terrainHeight = 0;
                            if (layer.relativeHeight && results.heights != null)                             //if checbox enabled and heights exist (at least one height generator is in the graph)
                            {
                                terrainHeight = results.heights.GetInterpolated(obj.pos.x, obj.pos.y);
                            }
                            if (terrainHeight > 1)
                            {
                                terrainHeight = 1;
                            }


                            //terrain-space object position
                            Vector3 position = new Vector3(
                                (obj.pos.x - hash.offset.x) / hash.size * terrainSize.dimensions,
                                (obj.height + terrainHeight) * terrainSize.height,
                                (obj.pos.y - hash.offset.y) / hash.size * terrainSize.dimensions);

                            //cell number
                            int cx = (int)(position.x / cellSize);
                            int cz = (int)(position.z / cellSize);
                            PersistentVegetationCell cell = storage.PersistentVegetationStoragePackage.PersistentVegetationCellList[cz + cx * cellXCount];

                            //rotation + taking terrain normal
                            Quaternion rotation;
                            float      objRotation = layer.rotate ? obj.rotation % 360 : 0;
                            if (layer.takeTerrainNormal)
                            {
                                Vector3 terrainNormal = ObjectOutput.GetTerrainNormal(obj.pos.x, obj.pos.y, results.heights, terrainSize.height, terrainSize.pixelSize);
                                Vector3 sideVector    = new Vector3(Mathf.Sin((obj.rotation + 90) * Mathf.Deg2Rad), 0, Mathf.Cos((obj.rotation + 90) * Mathf.Deg2Rad));
                                Vector3 frontVector   = Vector3.Cross(sideVector, terrainNormal);
                                rotation = Quaternion.LookRotation(frontVector, terrainNormal);
                            }
                            else
                            {
                                rotation = objRotation.EulerToQuat();
                            }

                            //scale + biome scale mode
                            Vector3 scale = layer.scale ? new Vector3(layer.scaleY ? 1 : obj.size, obj.size, layer.scaleY ? 1 : obj.size) : Vector3.one;

                            if (biomeBlendType == ObjectOutput.BiomeBlendType.Scale && gen.biome != null)
                            {
                                float biomeVal = 1;
                                if (biomeMask != null)
                                {
                                    biomeVal = biomeMask[obj.pos];
                                }
                                if (biomeVal < 0.001f)
                                {
                                    continue;                                                     //skip zero-scaled objects
                                }
                                scale *= biomeVal;
                            }

                            //storage.AddVegetationItemInstance(id, position, scale, rotation, layer.applyMeshRotation, VS_MM_id, true);
                            cell.AddVegetationItemInstance(id, position, scale, rotation, VS_MM_id);
                        }

                        if (stop != null && stop(0))
                        {
                            return;
                        }
                    }


                    //map outputs
                    if (layer.type == Layer.Type.Map)
                    {
                        //reading output directly
                        //Output output = gen.layers[b].output;
                        //if (stop!=null && stop(0)) return; //checking stop before reading output
                        //if (!results.results.ContainsKey(output)) continue;
                        //Matrix matrix = (Matrix)results.results[output];

                        //loading from input
                        if (stop != null && stop(0))
                        {
                            return;
                        }
                        Matrix matrix = (Matrix)gen.layers[b].mapInput.GetObject(results);
                        if (matrix == null)
                        {
                            continue;
                        }
                        Matrix heights = results.heights;                         //get heights before the chunk is removed

                        //setting bush by bush using the sample dist
                        float sampleDist = 1f / layer.density;

                        //filling
                        //float terrainPosX = 1f*rect.offset.x/terrainSize.resolution*terrainSize.dimensions;
                        //float terrainPosZ = 1f*rect.offset.z/terrainSize.resolution*terrainSize.dimensions;



                        for (int cx = 0; cx <= cellXCount - 1; cx++)
                        {
                            for (int cz = 0; cz <= cellZCount - 1; cz++)
                            {
                                //Vector3 cellCorner = new Vector3(terrainPosX + (cellSize * cx), 0, terrainPosZ + (cellSize * cz));
                                PersistentVegetationCell cell = storage.PersistentVegetationStoragePackage.PersistentVegetationCellList[cz + cx * cellXCount];

                                for (float x = 0; x < cellSize; x += sampleDist)
                                {
                                    for (float z = 0; z < cellSize; z += sampleDist)
                                    {
                                        //world position
                                        float wx = cellSize * cx + x;
                                        float wz = cellSize * cz + z;

                                        //randomizing position
                                        wx += noise.Random((int)(wx * 10), (int)(wz * 10), 2) * sampleDist - sampleDist / 2;
                                        wz += noise.Random((int)(wx * 10), (int)(wz * 10), 3) * sampleDist - sampleDist / 2;

                                        //map position
                                        float mx = wx / terrainSize.dimensions * rect.size.x + rect.offset.x;                                    // relative (0-1) position * terrain res
                                        float mz = wz / terrainSize.dimensions * rect.size.z + rect.offset.z;

                                        float val = matrix.GetInterpolated(mx, mz);

                                        float biomeFactor = 0;
                                        if (gen.biome == null)
                                        {
                                            biomeFactor = 1;
                                        }
                                        else if (biomeMask != null)
                                        {
                                            biomeFactor = biomeMask.GetInterpolated(mx, mz);
                                        }

                                        //placing object
                                        float rnd = (noise.Random((int)(wx * 10), (int)(wz * 10)));
                                        if (rnd < val * biomeFactor)
                                        {
                                            float terrainHeight = heights.GetInterpolated(mx, mz) * terrainSize.height;

                                            //rotation + taking terrain normal
                                            Quaternion rotation;
                                            float      rotRnd      = noise.Random((int)(wx * 10), (int)(wz * 10), 1);
                                            float      objRotation = layer.rotate ? rotRnd * 360 : 0;
                                            if (layer.takeTerrainNormal)
                                            {
                                                Vector3 terrainNormal = ObjectOutput.GetTerrainNormal(mx, mz, heights, terrainSize.height, terrainSize.pixelSize);
                                                Vector3 sideVector    = new Vector3(Mathf.Sin((objRotation + 90) * Mathf.Deg2Rad), 0, Mathf.Cos((objRotation + 90) * Mathf.Deg2Rad));
                                                Vector3 frontVector   = Vector3.Cross(sideVector, terrainNormal);
                                                rotation = Quaternion.LookRotation(frontVector, terrainNormal);
                                            }
                                            else
                                            {
                                                rotation = objRotation.EulerToQuat();
                                            }

                                            //scale
                                            float rndScale = noise.Random((int)(wx * 10), (int)(wz * 10), 1);
                                            rndScale = layer.scaleMinMax.x + (layer.scaleMinMax.y - layer.scaleMinMax.x) * rndScale;
                                            Vector3 scale = new Vector3(rndScale, rndScale, rndScale);

                                            //storage.AddVegetationItemInstance(id, new Vector3(wx,terrainHeight,wz), scale, rotation, layer.applyMeshRotation, VS_MM_id, true);
                                            cell.AddVegetationItemInstance(id, new Vector3(wx, terrainHeight, wz), scale, rotation, VS_MM_id);
                                        }
                                    }
                                }

                                if (stop != null && stop(0))
                                {
                                    return;
                                }
                            }
                        }
                    }
                }
            }

            //refreshing billboards
            //calling it from thread ruins all the billboards
            //BillboardSystem billboardSys = billboardComponents[rect];
            //if (billboardSys != null)
            //	 billboardSys.RefreshBillboards();
                        #endif

            //pushing anything to apply
            if (stop != null && stop(0))
            {
                return;
            }
            results.apply.CheckAdd(typeof(VegetationStudioOutput), null, replace: true);
        }