OctAtlas.h

#pragma once
#include "Rendering/ITextures.h"
 
#include <vector>
 
namespace Cogs
{
  namespace Core
  {
    struct CameraData;
    struct DrawContext;
 
    namespace Volumetric
    {
      struct OctComponent;
      struct OctData;
      struct Slot;
 
      struct OctAtlas
      {
        struct Slot
        {
          enum Flags : uint16_t {
            None = 0,
            InStaging = 1,    
            Invalid = 2,      
            NoData = 4        
          };
 
          uint64_t tileKey;
          uint64_t clientData;
          uint32_t timestampNeeded; 
          uint32_t timestapUpdated; 
          Flags flags;
        };
 
        std::vector<Slot> slots;
        std::list<uint32_t> slotsLRU;
        std::unordered_map<TileKey, uint32_t> slotsLUT;
 
        // Source=value, contains normal.xyz + value in w.
        // Source=valueAlpha, contains normal.xyz + alpha in w
        Cogs::TextureHandle textureAtlas0;
 
        // Source=valueAlpha, contains value.
        Cogs::TextureHandle textureAtlas1;
 
        // Returns stale-ness of tile. Zero staleness implies no need for issue.
        unsigned checkTile(const uint64_t tilekey, const uint32_t nodeTimestamp, const uint32_t currentTimestamp);
 
        void enforceOrder(const uint32_t currentTimestamp);
 
        glm::uvec4 slotPosition(const OctComponent& octComp, const uint64_t tileKey) const;
 
        struct Item
        {
          Cogs::TextureHandle texture0;
          Cogs::TextureHandle texture1;
          uint32_t slot;
          uint32_t delay;
        };
 
        std::vector<Item> toCopy;
        std::vector<Item> stagingUnused;
 
        void handleStaging(const DrawContext * renderingContext, OctComponent& octComp, OctData& octData, const uint32_t currentTimestamp, unsigned delay = 3);
 
        void reset(const DrawContext * renderingContext, const OctData& octData, const uint32_t tileSize, const uint32_t gpuCacheSize, const uint32_t currentTimestamp);
 
      };
 
    }
  }
}