1 files changed, 746 insertions, 0 deletions

diff --git a/OpenSim/Region/ClientStack/Linden/Caps/BunchOfCaps/MeshCost.cs b/OpenSim/Region/ClientStack/Linden/Caps/BunchOfCaps/MeshCost.cs
new file mode 100644
index 0000000..eb1ab45
--- /dev/null
+++ b/OpenSim/Region/ClientStack/Linden/Caps/BunchOfCaps/MeshCost.cs
@@ -0,0 +1,746 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+using System;
+using System.IO;
+using System.Collections;
+using System.Collections.Generic;
+using System.Text;
+
+using OpenMetaverse;
+using OpenMetaverse.StructuredData;
+
+using OpenSim.Framework;
+using OpenSim.Region.Framework;
+using OpenSim.Region.Framework.Scenes;
+using OpenSim.Framework.Capabilities;
+
+using ComponentAce.Compression.Libs.zlib;
+
+using OSDArray = OpenMetaverse.StructuredData.OSDArray;
+using OSDMap = OpenMetaverse.StructuredData.OSDMap;
+
+using Nini.Config;
+
+namespace OpenSim.Region.ClientStack.Linden
+{
+    public struct ModelPrimLimits
+    {
+
+    }
+
+    public class ModelCost
+    {
+
+        // upload fee defaults
+        // fees are normalized to 1.0
+        // this parameters scale them to basic cost ( so 1.0 translates to 10 )
+
+        public float ModelMeshCostFactor = 0.0f; // scale total cost relative to basic (excluding textures)
+        public float ModelTextureCostFactor = 1.0f; // scale textures fee to basic.
+        public float ModelMinCostFactor = 0.0f; // 0.5f; // minimum total model free excluding textures
+
+        // itens costs in normalized values
+        // ie will be multiplied by basicCost and factors above
+        public float primCreationCost = 0.002f;  // extra cost for each prim creation overhead
+        // weigthed size to normalized cost
+        public float bytecost = 1e-5f;
+
+        // mesh upload fees based on compressed data sizes
+        // several data sections are counted more that once
+        // to promote user optimization
+        // following parameters control how many extra times they are added
+        // to global size.
+        // LOD meshs
+        const float medSizeWth = 1f; // 2x
+        const float lowSizeWth = 1.5f; // 2.5x
+        const float lowestSizeWth = 2f; // 3x
+        // favor potencially physical optimized meshs versus automatic decomposition
+        const float physMeshSizeWth = 6f; // counts  7x
+        const float physHullSizeWth = 8f; // counts  9x
+
+        // stream cost area factors
+        // more or less like SL
+        const float highLodFactor = 17.36f;
+        const float midLodFactor = 277.78f;
+        const float lowLodFactor = 1111.11f;
+
+        // physics cost is below, identical to SL, assuming shape type convex
+        // server cost is below identical to SL assuming non scripted non physical object
+
+        // internal
+        const int bytesPerCoord = 6; // 3 coords, 2 bytes per each
+
+        // control prims dimensions
+        public float PrimScaleMin = 0.001f;
+        public float NonPhysicalPrimScaleMax = 256f;
+        public float PhysicalPrimScaleMax = 10f;
+        public int ObjectLinkedPartsMax = 512;
+
+
+        public ModelCost(Scene scene)
+        {
+            PrimScaleMin = scene.m_minNonphys;
+            NonPhysicalPrimScaleMax = scene.m_maxNonphys;
+            PhysicalPrimScaleMax = scene.m_maxPhys;
+            ObjectLinkedPartsMax = scene.m_linksetCapacity;
+        }
+
+        public void Econfig(IConfig EconomyConfig)
+        {
+            ModelMeshCostFactor = EconomyConfig.GetFloat("MeshModelUploadCostFactor", ModelMeshCostFactor);
+            ModelTextureCostFactor = EconomyConfig.GetFloat("MeshModelUploadTextureCostFactor", ModelTextureCostFactor);
+            ModelMinCostFactor = EconomyConfig.GetFloat("MeshModelMinCostFactor", ModelMinCostFactor);
+                    // next 2 are normalized so final cost is afected by modelUploadFactor above and normal cost
+            primCreationCost = EconomyConfig.GetFloat("ModelPrimCreationCost", primCreationCost);
+            bytecost = EconomyConfig.GetFloat("ModelMeshByteCost", bytecost);
+        }
+
+        // storage for a single mesh asset cost parameters
+        private class ameshCostParam
+        {
+            // LOD sizes for size dependent streaming cost
+            public int highLODSize;
+            public int medLODSize;
+            public int lowLODSize;
+            public int lowestLODSize;
+            // normalized fee based on compressed data sizes
+            public float costFee;
+            // physics cost
+            public float physicsCost;
+        }
+
+        // calculates a mesh model costs
+        // returns false on error, with a reason on parameter error
+        // resources input LLSD request
+        // basicCost input region assets upload cost
+        // totalcost returns model total upload fee
+        // meshcostdata returns detailed costs for viewer
+        // avatarSkeleton if mesh includes a avatar skeleton
+        // useAvatarCollider if we should use physics mesh for avatar
+        public bool MeshModelCost(LLSDAssetResource resources, int basicCost, out int totalcost,
+            LLSDAssetUploadResponseData meshcostdata, out string error, ref string warning)
+        {
+            totalcost = 0;
+            error = string.Empty;
+
+            bool avatarSkeleton = false;
+
+            if (resources == null ||
+                resources.instance_list == null ||
+                resources.instance_list.Array.Count == 0)
+            {
+                error = "missing model information.";
+                return false;
+            }
+
+            int numberInstances = resources.instance_list.Array.Count;
+
+            if (ObjectLinkedPartsMax != 0 && numberInstances > ObjectLinkedPartsMax)
+            {
+                error = "Model would have more than " + ObjectLinkedPartsMax.ToString() + " linked prims";
+                return false;
+            }
+
+            meshcostdata.model_streaming_cost = 0.0;
+            meshcostdata.simulation_cost = 0.0;
+            meshcostdata.physics_cost = 0.0;
+            meshcostdata.resource_cost = 0.0;
+
+            meshcostdata.upload_price_breakdown.mesh_instance = 0;
+            meshcostdata.upload_price_breakdown.mesh_physics = 0;
+            meshcostdata.upload_price_breakdown.mesh_streaming = 0;
+            meshcostdata.upload_price_breakdown.model = 0;
+
+            int itmp;
+
+            // textures cost
+            if (resources.texture_list != null && resources.texture_list.Array.Count > 0)
+            {
+                float textures_cost = (float)(resources.texture_list.Array.Count * basicCost);
+                textures_cost *= ModelTextureCostFactor;
+
+                itmp = (int)(textures_cost + 0.5f); // round
+                meshcostdata.upload_price_breakdown.texture = itmp;
+                totalcost += itmp;
+            }
+
+            // meshs assets cost
+            float meshsfee = 0;
+            int numberMeshs = 0;
+            bool haveMeshs = false;
+
+            bool curskeleton;
+            bool curAvatarPhys;
+
+            List<ameshCostParam> meshsCosts = new List<ameshCostParam>();
+
+            if (resources.mesh_list != null && resources.mesh_list.Array.Count > 0)
+            {
+                numberMeshs = resources.mesh_list.Array.Count;
+
+                for (int i = 0; i < numberMeshs; i++)
+                {
+                    ameshCostParam curCost = new ameshCostParam();
+                    byte[] data = (byte[])resources.mesh_list.Array[i];
+
+                    if (!MeshCost(data, curCost,out curskeleton, out curAvatarPhys, out error))
+                    {
+                        return false;
+                    }
+
+                    if (curskeleton)
+                    {
+                        if (avatarSkeleton)
+                        {
+                            error = "model can only contain a avatar skeleton";
+                            return false;
+                        }
+                        avatarSkeleton = true;
+                    }
+                    meshsCosts.Add(curCost);
+                    meshsfee += curCost.costFee;
+                }
+                haveMeshs = true;
+            }
+
+            // instances (prims) cost
+
+
+            int mesh;
+            int skipedSmall = 0;
+            for (int i = 0; i < numberInstances; i++)
+            {
+                Hashtable inst = (Hashtable)resources.instance_list.Array[i];
+
+                ArrayList ascale = (ArrayList)inst["scale"];
+                Vector3 scale;
+                double tmp;
+                tmp = (double)ascale[0];
+                scale.X = (float)tmp;
+                tmp = (double)ascale[1];
+                scale.Y = (float)tmp;
+                tmp = (double)ascale[2];
+                scale.Z = (float)tmp;
+
+                if (scale.X < PrimScaleMin || scale.Y < PrimScaleMin || scale.Z < PrimScaleMin)
+                {
+                    skipedSmall++;
+                    continue;
+                }
+
+                if (scale.X > NonPhysicalPrimScaleMax || scale.Y > NonPhysicalPrimScaleMax || scale.Z > NonPhysicalPrimScaleMax)
+                {
+                    error = "Model contains parts with sides larger than " + NonPhysicalPrimScaleMax.ToString() + "m. Please ajust scale";
+                    return false;
+                }
+
+                if (haveMeshs && inst.ContainsKey("mesh"))
+                {
+                    mesh = (int)inst["mesh"];
+
+                    if (mesh >= numberMeshs)
+                    {
+                        error = "Incoerent model information.";
+                        return false;
+                    }
+
+                    // streamming cost
+
+                    float sqdiam = scale.LengthSquared();
+
+                    ameshCostParam curCost = meshsCosts[mesh];
+                    float mesh_streaming = streamingCost(curCost, sqdiam);
+
+                    meshcostdata.model_streaming_cost += mesh_streaming;
+                    meshcostdata.physics_cost += curCost.physicsCost;
+                }
+                else // instance as no mesh ??
+                {
+                    // to do later if needed
+                    meshcostdata.model_streaming_cost += 0.5f;
+                    meshcostdata.physics_cost += 1.0f;
+                }
+
+                // assume unscripted and static prim server cost
+                meshcostdata.simulation_cost += 0.5f;
+                // charge for prims creation
+                meshsfee += primCreationCost;
+            }
+
+            if (skipedSmall > 0)
+            {
+                if (skipedSmall > numberInstances / 2)
+                {
+                    error = "Model contains too many prims smaller than " + PrimScaleMin.ToString() +
+                        "m minimum allowed size. Please check scalling";
+                    return false;
+                }
+                else
+                    warning += skipedSmall.ToString() + " of the requested " +numberInstances.ToString() +
+                        " model prims will not upload because they are smaller than " + PrimScaleMin.ToString() +
+                        "m minimum allowed size. Please check scalling ";
+            }
+
+            if (meshcostdata.physics_cost <= meshcostdata.model_streaming_cost)
+                meshcostdata.resource_cost = meshcostdata.model_streaming_cost;
+            else
+                meshcostdata.resource_cost = meshcostdata.physics_cost;
+
+            if (meshcostdata.resource_cost < meshcostdata.simulation_cost)
+                meshcostdata.resource_cost = meshcostdata.simulation_cost;
+
+            // scale cost
+            // at this point a cost of 1.0 whould mean basic cost
+            meshsfee *= ModelMeshCostFactor;
+
+            if (meshsfee < ModelMinCostFactor)
+                meshsfee = ModelMinCostFactor;
+
+            // actually scale it to basic cost
+            meshsfee *= (float)basicCost;
+
+            meshsfee += 0.5f; // rounding
+
+            totalcost += (int)meshsfee;
+
+            // breakdown prices
+            // don't seem to be in use so removed code for now
+
+            return true;
+        }
+
+        // single mesh asset cost
+        private bool MeshCost(byte[] data, ameshCostParam cost,out bool skeleton, out bool avatarPhys, out string error)
+        {
+            cost.highLODSize = 0;
+            cost.medLODSize = 0;
+            cost.lowLODSize = 0;
+            cost.lowestLODSize = 0;
+            cost.physicsCost = 0.0f;
+            cost.costFee = 0.0f;
+
+            error = string.Empty;
+
+            skeleton = false;
+            avatarPhys = false;
+
+            if (data == null || data.Length == 0)
+            {
+                error = "Missing model information.";
+                return false;
+            }
+
+            OSD meshOsd = null;
+            int start = 0;
+
+            error = "Invalid model data";
+
+            using (MemoryStream ms = new MemoryStream(data))
+            {
+                try
+                {
+                    OSD osd = OSDParser.DeserializeLLSDBinary(ms);
+                    if (osd is OSDMap)
+                        meshOsd = (OSDMap)osd;
+                    else
+                        return false;
+                }
+                catch
+                {
+                    return false;
+                }
+                start = (int)ms.Position;
+            }
+
+            OSDMap map = (OSDMap)meshOsd;
+            OSDMap tmpmap;
+
+            int highlod_size = 0;
+            int medlod_size = 0;
+            int lowlod_size = 0;
+            int lowestlod_size = 0;
+            int skin_size = 0;
+
+            int hulls_size = 0;
+            int phys_nhulls;
+            int phys_hullsvertices = 0;
+
+            int physmesh_size = 0;
+            int phys_ntriangles = 0;
+
+            int submesh_offset = -1;
+
+            if (map.ContainsKey("skeleton"))
+            {
+                tmpmap = (OSDMap)map["skeleton"];
+                if (tmpmap.ContainsKey("offset") && tmpmap.ContainsKey("size"))
+                {
+                    int sksize = tmpmap["size"].AsInteger();
+                    if(sksize > 0)
+                        skeleton = true;
+                }
+            }
+
+            if (map.ContainsKey("physics_convex"))
+            {
+                tmpmap = (OSDMap)map["physics_convex"];
+                if (tmpmap.ContainsKey("offset"))
+                    submesh_offset = tmpmap["offset"].AsInteger() + start;
+                if (tmpmap.ContainsKey("size"))
+                    hulls_size = tmpmap["size"].AsInteger();
+            }
+
+            if (submesh_offset < 0 || hulls_size == 0)
+            {
+                error = "Missing physics_convex block";
+                return false;
+            }
+
+            if (!hulls(data, submesh_offset, hulls_size, out phys_hullsvertices, out phys_nhulls))
+            {
+                error = "Bad physics_convex block";
+                return false;
+            }
+
+            submesh_offset = -1;
+
+            // only look for LOD meshs sizes
+
+            if (map.ContainsKey("high_lod"))
+            {
+                tmpmap = (OSDMap)map["high_lod"];
+                // see at least if there is a offset for this one
+                if (tmpmap.ContainsKey("offset"))
+                    submesh_offset = tmpmap["offset"].AsInteger() + start;
+                if (tmpmap.ContainsKey("size"))
+                    highlod_size = tmpmap["size"].AsInteger();
+            }
+
+            if (submesh_offset < 0 || highlod_size <= 0)
+            {
+                error = "Missing high_lod block";
+                return false;
+            }
+
+            bool haveprev = true;
+
+            if (map.ContainsKey("medium_lod"))
+            {
+                tmpmap = (OSDMap)map["medium_lod"];
+                if (tmpmap.ContainsKey("size"))
+                    medlod_size = tmpmap["size"].AsInteger();
+                else
+                    haveprev = false;
+            }
+
+            if (haveprev && map.ContainsKey("low_lod"))
+            {
+                tmpmap = (OSDMap)map["low_lod"];
+                if (tmpmap.ContainsKey("size"))
+                    lowlod_size = tmpmap["size"].AsInteger();
+                else
+                    haveprev = false;
+            }
+
+            if (haveprev && map.ContainsKey("lowest_lod"))
+            {
+                tmpmap = (OSDMap)map["lowest_lod"];
+                if (tmpmap.ContainsKey("size"))
+                    lowestlod_size = tmpmap["size"].AsInteger();
+            }
+
+            if (map.ContainsKey("skin"))
+            {
+                tmpmap = (OSDMap)map["skin"];
+                if (tmpmap.ContainsKey("size"))
+                    skin_size = tmpmap["size"].AsInteger();
+            }
+
+            cost.highLODSize = highlod_size;
+            cost.medLODSize = medlod_size;
+            cost.lowLODSize = lowlod_size;
+            cost.lowestLODSize = lowestlod_size;
+
+            submesh_offset = -1;
+
+            tmpmap = null;
+            if(map.ContainsKey("physics_mesh"))
+                tmpmap = (OSDMap)map["physics_mesh"];
+            else if (map.ContainsKey("physics_shape")) // old naming
+                tmpmap = (OSDMap)map["physics_shape"];
+
+            if(tmpmap != null)
+            {
+                if (tmpmap.ContainsKey("offset"))
+                    submesh_offset = tmpmap["offset"].AsInteger() + start;
+                if (tmpmap.ContainsKey("size"))
+                    physmesh_size = tmpmap["size"].AsInteger();
+
+                if (submesh_offset >= 0 || physmesh_size > 0)
+                {
+
+                    if (!submesh(data, submesh_offset, physmesh_size, out phys_ntriangles))
+                    {
+                        error = "Model data parsing error";
+                        return false;
+                    }
+                }
+            }
+
+            // upload is done in convex shape type so only one hull
+            phys_hullsvertices++;
+            cost.physicsCost = 0.04f * phys_hullsvertices;
+
+            float sfee;
+
+            sfee = data.Length; // start with total compressed data size
+
+            // penalize lod meshs that should be more builder optimized
+            sfee += medSizeWth * medlod_size;
+            sfee += lowSizeWth * lowlod_size;
+            sfee += lowestSizeWth * lowlod_size;
+
+            // physics
+            // favor potencial optimized meshs versus automatic decomposition
+            if (physmesh_size != 0)
+                sfee += physMeshSizeWth * (physmesh_size + hulls_size / 4); // reduce cost of mandatory convex hull
+            else
+                sfee += physHullSizeWth * hulls_size;
+
+            // bytes to money
+            sfee *= bytecost;
+
+            cost.costFee = sfee;
+            return true;
+        }
+
+        // parses a LOD or physics mesh component
+        private bool submesh(byte[] data, int offset, int size, out int ntriangles)
+        {
+            ntriangles = 0;
+
+            OSD decodedMeshOsd = new OSD();
+            byte[] meshBytes = new byte[size];
+            System.Buffer.BlockCopy(data, offset, meshBytes, 0, size);
+            try
+            {
+                using (MemoryStream inMs = new MemoryStream(meshBytes))
+                {
+                    using (MemoryStream outMs = new MemoryStream())
+                    {
+                        using (ZOutputStream zOut = new ZOutputStream(outMs))
+                        {
+                            byte[] readBuffer = new byte[4096];
+                            int readLen = 0;
+                            while ((readLen = inMs.Read(readBuffer, 0, readBuffer.Length)) > 0)
+                            {
+                                zOut.Write(readBuffer, 0, readLen);
+                            }
+                            zOut.Flush();
+                            outMs.Seek(0, SeekOrigin.Begin);
+
+                            byte[] decompressedBuf = outMs.GetBuffer();
+                            decodedMeshOsd = OSDParser.DeserializeLLSDBinary(decompressedBuf);
+                        }
+                    }
+                }
+            }
+            catch
+            {
+                return false;
+            }
+
+            OSDArray decodedMeshOsdArray = null;
+
+            byte[] dummy;
+
+            decodedMeshOsdArray = (OSDArray)decodedMeshOsd;
+            foreach (OSD subMeshOsd in decodedMeshOsdArray)
+            {
+                if (subMeshOsd is OSDMap)
+                {
+                    OSDMap subtmpmap = (OSDMap)subMeshOsd;
+                    if (subtmpmap.ContainsKey("NoGeometry") && ((OSDBoolean)subtmpmap["NoGeometry"]))
+                        continue;
+
+                    if (!subtmpmap.ContainsKey("Position"))
+                        return false;
+
+                    if (subtmpmap.ContainsKey("TriangleList"))
+                    {
+                        dummy = subtmpmap["TriangleList"].AsBinary();
+                        ntriangles += dummy.Length / bytesPerCoord;
+                    }
+                    else
+                        return false;
+                }
+            }
+
+            return true;
+        }
+
+        // parses convex hulls component
+        private bool hulls(byte[] data, int offset, int size, out int nvertices, out int nhulls)
+        {
+            nvertices = 0;
+            nhulls = 1;
+
+            OSD decodedMeshOsd = new OSD();
+            byte[] meshBytes = new byte[size];
+            System.Buffer.BlockCopy(data, offset, meshBytes, 0, size);
+            try
+            {
+                using (MemoryStream inMs = new MemoryStream(meshBytes))
+                {
+                    using (MemoryStream outMs = new MemoryStream())
+                    {
+                        using (ZOutputStream zOut = new ZOutputStream(outMs))
+                        {
+                            byte[] readBuffer = new byte[4096];
+                            int readLen = 0;
+                            while ((readLen = inMs.Read(readBuffer, 0, readBuffer.Length)) > 0)
+                            {
+                                zOut.Write(readBuffer, 0, readLen);
+                            }
+                            zOut.Flush();
+                            outMs.Seek(0, SeekOrigin.Begin);
+
+                            byte[] decompressedBuf = outMs.GetBuffer();
+                            decodedMeshOsd = OSDParser.DeserializeLLSDBinary(decompressedBuf);
+                        }
+                    }
+                }
+            }
+            catch
+            {
+                return false;
+            }
+
+            OSDMap cmap = (OSDMap)decodedMeshOsd;
+            if (cmap == null)
+                return false;
+
+            byte[] dummy;
+
+            // must have one of this
+            if (cmap.ContainsKey("BoundingVerts"))
+            {
+                dummy = cmap["BoundingVerts"].AsBinary();
+                nvertices = dummy.Length / bytesPerCoord;
+            }
+            else
+                return false;
+
+/* upload is done with convex shape type
+            if (cmap.ContainsKey("HullList"))
+            {
+                dummy = cmap["HullList"].AsBinary();
+                nhulls += dummy.Length;
+            }
+
+
+            if (cmap.ContainsKey("Positions"))
+            {
+                dummy = cmap["Positions"].AsBinary();
+                nvertices = dummy.Length / bytesPerCoord;
+            }
+ */
+
+            return true;
+        }
+
+        // returns streaming cost from on mesh LODs sizes in curCost and square of prim size length
+        private float streamingCost(ameshCostParam curCost, float sqdiam)
+        {
+            // compute efective areas
+            float ma = 262144f;
+
+            float mh = sqdiam * highLodFactor;
+            if (mh > ma)
+                mh = ma;
+            float mm = sqdiam * midLodFactor;
+            if (mm > ma)
+                mm = ma;
+
+            float ml = sqdiam * lowLodFactor;
+            if (ml > ma)
+                ml = ma;
+
+            float mlst = ma;
+
+            mlst -= ml;
+            ml -= mm;
+            mm -= mh;
+
+            if (mlst < 1.0f)
+                mlst = 1.0f;
+            if (ml < 1.0f)
+                ml = 1.0f;
+            if (mm < 1.0f)
+                mm = 1.0f;
+            if (mh < 1.0f)
+                mh = 1.0f;
+
+            ma = mlst + ml + mm + mh;
+
+            // get LODs compressed sizes
+            // giving 384 bytes bonus
+            int lst = curCost.lowestLODSize - 384;
+            int l = curCost.lowLODSize - 384;
+            int m = curCost.medLODSize - 384;
+            int h = curCost.highLODSize - 384;
+
+            // use previus higher LOD size on missing ones
+            if (m <= 0)
+                m = h;
+            if (l <= 0)
+                l = m;
+            if (lst <= 0)
+                lst = l;
+
+            // force minumum sizes
+            if (lst < 16)
+                lst = 16;
+            if (l < 16)
+                l = 16;
+            if (m < 16)
+                m = 16;
+            if (h < 16)
+                h = 16;
+
+            // compute cost weighted by relative effective areas
+            float cost = (float)lst * mlst + (float)l * ml + (float)m * mm + (float)h * mh;
+            cost /= ma;
+
+            cost *= 0.004f; // overall tunning parameter
+
+            return cost;
+        }
+    }
+}