path: root/OpenSim/Region/ClientStack/LindenUDP/LLImageManager.cs

/*
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using System;
using System.Threading;
using System.Collections.Generic;
using OpenMetaverse;
using OpenMetaverse.Imaging;
using OpenSim.Framework;
using OpenSim.Region.Framework.Interfaces;
using OpenSim.Services.Interfaces;
using log4net;
using System.Reflection;

namespace OpenSim.Region.ClientStack.LindenUDP
{

    public class LLImageManager
    {
        
        //Public interfaces:
        //Constructor - (LLClientView, IAssetCache, IJ2KDecoder);
        //void EnqueueReq - (TextureRequestArgs)
        //ProcessImageQueue
        //Close
        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
        private bool m_shuttingdown = false;
        private long m_lastloopprocessed = 0;

        private LLClientView m_client; //Client we're assigned to
        private IAssetService m_assetCache; //Asset Cache
        private IJ2KDecoder m_j2kDecodeModule; //Our J2K module

        private readonly AssetBase m_missingsubstitute; //Sustitute for bad decodes
        private Dictionary<UUID,J2KImage> m_imagestore; // Our main image storage dictionary
        private SortedList<double,UUID> m_priorities; // For fast image lookup based on priority
        private Dictionary<int, int> m_priorityresolver; //Enabling super fast assignment of images with the same priorities

        private const double doubleMinimum = .0000001;

        public int m_outstandingtextures = 0;
        //Constructor
        public LLImageManager(LLClientView client, IAssetService pAssetCache, IJ2KDecoder pJ2kDecodeModule)
        {
            
            m_imagestore = new Dictionary<UUID,J2KImage>();
            m_priorities = new SortedList<double,UUID>();
            m_priorityresolver = new Dictionary<int, int>();
            m_client = client;
            m_assetCache = pAssetCache;
            if (pAssetCache != null)
                m_missingsubstitute = pAssetCache.Get("5748decc-f629-461c-9a36-a35a221fe21f");
            else
                m_log.Error("[ClientView] - couldn't set missing image, all manner of things will probably break");
            m_j2kDecodeModule = pJ2kDecodeModule;
        }

        public void EnqueueReq(TextureRequestArgs newRequest)
        {
            //newRequest is the properties of our new texture fetch request.
            //Basically, here is where we queue up "new" requests..
            // .. or modify existing requests to suit.

            //Make sure we're not shutting down..
            if (!m_shuttingdown)
            {

                //Do we already know about this UUID?
                if (m_imagestore.ContainsKey(newRequest.RequestedAssetID))
                {
                    //Check the packet sequence to make sure this isn't older than 
                    //one we've already received

                    J2KImage imgrequest = m_imagestore[newRequest.RequestedAssetID];

                    // This is the inbound request sequence number. We can ignore
                    // "old" ones.

                    if (newRequest.requestSequence > imgrequest.m_lastSequence)
                    {

                        imgrequest.m_lastSequence = newRequest.requestSequence;

                        //Check the priority

                        double priority = imgrequest.m_requestedPriority;
                        if (priority != newRequest.Priority)
                        {
                            //Remove the old priority
                            m_priorities.Remove(imgrequest.m_designatedPriorityKey);
                            //Assign a new unique priority
                            imgrequest.m_requestedPriority = newRequest.Priority;
                            imgrequest.m_designatedPriorityKey = AssignPriority(newRequest.RequestedAssetID, newRequest.Priority);
                        }

                        //Update the requested discard level
                        imgrequest.m_requestedDiscardLevel = newRequest.DiscardLevel;

                        //Update the requested packet number
                        imgrequest.m_requestedPacketNumber = newRequest.PacketNumber;

                        //Check if this will create an outstanding texture request
                        bool activated = imgrequest.m_completedSendAtCurrentDiscardLevel;
                        //Run an update

                        imgrequest.RunUpdate();

                        if (activated && !imgrequest.m_completedSendAtCurrentDiscardLevel && imgrequest.m_decoded)
                        {
                            Interlocked.Increment(ref m_outstandingtextures);
                        }
                    }
                }
                else
                {
                    J2KImage imgrequest = new J2KImage(this);

                    //Assign our missing substitute
                    imgrequest.m_MissingSubstitute = m_missingsubstitute;

                    //Assign our decoder module
                    imgrequest.m_j2kDecodeModule = m_j2kDecodeModule;

                    //Assign our asset cache module
                    imgrequest.m_assetCache = m_assetCache;

                    //Assign a priority based on our request
                    imgrequest.m_designatedPriorityKey = AssignPriority(newRequest.RequestedAssetID, newRequest.Priority);

                    //Assign the requested discard level
                    imgrequest.m_requestedDiscardLevel = newRequest.DiscardLevel;

                    //Assign the requested packet number
                    imgrequest.m_requestedPacketNumber = newRequest.PacketNumber;

                    //Assign the requested priority
                    imgrequest.m_requestedPriority = newRequest.Priority;

                    //Assign the asset uuid
                    imgrequest.m_requestedUUID = newRequest.RequestedAssetID;

                    m_imagestore.Add(imgrequest.m_requestedUUID, imgrequest);

                    //Run an update
                    imgrequest.RunUpdate();

                }
            }
        }

        private double AssignPriority(UUID pAssetID, double pPriority)
        {
            
            //First, find out if we can just assign directly
            if (m_priorityresolver.ContainsKey((int)pPriority) == false)
            {
                m_priorities.Add((double)((int)pPriority), pAssetID);
                m_priorityresolver.Add((int)pPriority, 0);
                return (double)((int)pPriority);
            }
            else
            {
                //Use the hash lookup goodness of a secondary dictionary to find a free slot
                double mFreePriority = ((int)pPriority) + (doubleMinimum * (m_priorityresolver[(int)pPriority] + 1));
                m_priorities[mFreePriority] = pAssetID;
                m_priorityresolver[(int)pPriority]++;
                return mFreePriority;
            }



        }

        public bool ProcessImageQueue(int count, int maxpack)
        {

            // this can happen during Close()
            if (m_client == null)
                return false;
            
            //Count is the number of textures we want to process in one go.
            //As part of this class re-write, that number will probably rise
            //since we're processing in a more efficient manner.
            
            int numCollected = 0;

             //Calculate our threshold
             int threshold;
             if (m_lastloopprocessed == 0)
             {
                  if (m_client.PacketHandler == null || m_client.PacketHandler.PacketQueue == null || m_client.PacketHandler.PacketQueue.TextureThrottle == null)
                      return false;
                 //This is decent for a semi fast machine, but we'll calculate it more accurately based on time below
                  threshold = m_client.PacketHandler.PacketQueue.TextureThrottle.Current / 6300;
                  m_lastloopprocessed = DateTime.Now.Ticks;
             }
             else
             {
                 double throttleseconds = ((double)DateTime.Now.Ticks - (double)m_lastloopprocessed) / (double)TimeSpan.TicksPerSecond;
                 throttleseconds = throttleseconds * m_client.PacketHandler.PacketQueue.TextureThrottle.Current;
 
                 //Average of 1000 bytes per packet
                 throttleseconds = throttleseconds / 1000;
 
                 //Safe-zone multiplier of 2.0
                 threshold = (int)(throttleseconds * 2.0);
                 m_lastloopprocessed = DateTime.Now.Ticks;
 
             }
             
             if (threshold < 10)
             {
                 threshold = 10;
             }

             if (m_client.PacketHandler == null)
                 return false;

             if (m_client.PacketHandler.PacketQueue == null)
                 return false;

            //First of all make sure our packet queue isn't above our threshold 

            //Uncomment this to see what the texture stack is doing
             //m_log.Debug("Queue: " + m_client.PacketHandler.PacketQueue.TextureOutgoingPacketQueueCount.ToString() + " Threshold: " + threshold.ToString() + " outstanding: " + m_outstandingtextures.ToString());
             if (m_client.PacketHandler.PacketQueue.TextureOutgoingPacketQueueCount < threshold && m_outstandingtextures > 0)
             {
                bool justreset = false;
            
                for (int x = m_priorities.Count - 1; x > -1; x--)
                {
                    
                    J2KImage imagereq = m_imagestore[m_priorities.Values[x]];
                    if (imagereq.m_decoded == true && !imagereq.m_completedSendAtCurrentDiscardLevel)
                    {
                        // we need to test this here now that we are dropping assets
                        if (!imagereq.m_hasasset)
                        {
                            m_log.WarnFormat("[LLIMAGE MANAGER]: Re-requesting the image asset {0}", imagereq.m_requestedUUID);
                            imagereq.RunUpdate();
                            continue;
                        }

                        numCollected++;
                        //SendPackets will send up to ten packets per cycle
                        if (imagereq.SendPackets(m_client, maxpack))
                        {
                            //Send complete
                            if (!imagereq.m_completedSendAtCurrentDiscardLevel)
                            {
                                // I think this field imagereq.m_completedSendAtCurrentDiscardLevel
                                // is completely redundant
                                //imagereq.m_completedSendAtCurrentDiscardLevel = true;

                                Interlocked.Decrement(ref m_outstandingtextures);

                                // First and foremost, drop the reference to the asset
                                // so that the asset doesn't stay in memory forever.
                                // We'll Get it again from the asset service (usually cache)
                                // if/when the client requests it again.
                                // In order not to mess much with the current implementation
                                // of this management code, we drop only the asset reference
                                // but keep the image request itself.
                                imagereq.DropAsset();

                                //Re-assign priority to bottom
                                //Remove the old priority
                                m_priorities.Remove(imagereq.m_designatedPriorityKey);
                                int lowest;
                                if (m_priorities.Count > 0)
                                {
                                    lowest = (int)m_priorities.Keys[0];
                                    lowest--;
                                }
                                else
                                {
                                    lowest = -10000;
                                }
                                m_priorities.Add((double)lowest, imagereq.m_requestedUUID);
                                imagereq.m_designatedPriorityKey = (double)lowest;
                                if (m_priorityresolver.ContainsKey((int)lowest))
                                {
                                    m_priorityresolver[(int)lowest]++;
                                }
                                else
                                {
                                    m_priorityresolver.Add((int)lowest, 0);
                                }
                            }
                        }
                        if (numCollected == count)
                        {
                            break;
                        }
                    }
                    if (numCollected == count || m_outstandingtextures == 0)
                        break;
                    if (numCollected % m_outstandingtextures == 0 && !justreset)
                    {
                        //We've gotten as much as we can from the stack,
                        //reset to the top so that we can send MOAR DATA (nomnomnom)!
                        x = m_priorities.Count - 1;

                        justreset = true; //prevents us from getting stuck in a loop
                    }
                }
            }

            return m_outstandingtextures != 0;
        }

        //Faux destructor
        public void Close()
        {
            
            m_shuttingdown = true;
            m_j2kDecodeModule = null;
            m_assetCache = null;
            m_client = null;
        }


    }
}