RenderStates.h

#pragma once
#include "Base.h"
 
#include <unordered_map>
#include <vector>
 
#include "Rendering/Common.h"
#include "Rendering/RasterizerState.h"
#include "Rendering/DepthStencilState.h"
#include "Rendering/SamplerState.h"
#include "Rendering/BlendState.h"
 
#include "Resources/MaterialOptions.h"
 
namespace Cogs
{
  class IGraphicsDevice;
 
  namespace Core
  {
    constexpr uint16_t getDepthState(DepthMode depthMode, DepthFunc depthFunc) { return (uint16_t)depthMode + (uint16_t)DepthMode::Count * (uint16_t)depthFunc; }
 
    struct RenderPassOptions;
 
    struct RenderStates
    {
      void initialize(IGraphicsDevice * device);
      void setupDepthStates(IGraphicsDevice* device);
      void cleanup();
 
      bool reverseDepth = false;
 
      Cogs::RasterizerStateHandle defaultRasterizerStateHandle;
      Cogs::RasterizerStateHandle defaultCCWasterizerStateHandle;
 
      std::vector<Cogs::RasterizerStateHandle> rasterizerStateHandles;
 
      struct {
        Cogs::BlendState color = Cogs::BlendState::DefaultState();
        Cogs::BlendState alpha = Cogs::BlendState::DefaultState();
        Cogs::BlendStateHandle handle = Cogs::BlendStateHandle::NoHandle;
      } blendStates[size_t(BlendMode::Count)];
 
      static constexpr uint16_t defaultDepthStencilState = getDepthState(DepthMode::Default, DepthFunc::Less);
      static constexpr uint16_t noWriteDepthStencilState = getDepthState(DepthMode::NoWrite, DepthFunc::Less);
      static constexpr uint16_t noDepthStencilState = getDepthState(DepthMode::Disabled, DepthFunc::Always);
      static constexpr uint16_t noTestDepthStencilState = getDepthState(DepthMode::Default, DepthFunc::Always);
      static constexpr uint16_t leqDepthStencilState = getDepthState(DepthMode::Default, DepthFunc::LessOrEqual);
 
      Cogs::DepthStencilStateHandle commonDepthStates[(int)DepthMode::Count*(int)DepthFunc::Count];
 
      // MinMagMipLinear, Wrap, 0x Anisotropic
      Cogs::SamplerStateHandle defaultSampler;
 
      Cogs::SamplerStateHandle commonSamplerStates[4];
 
      // ComparisonMinMagMipLinear, Clamp, ComparisonLessEqual
      Cogs::SamplerStateHandle shadowSampler;
 
      // Single triangle that covers the full screen.
      Cogs::VertexBufferHandle fullScreenTriangle;
 
      uint16_t COGSCORE_DLL_API getRasterizerState(const Cogs::Core::RenderPassOptions& passOptions,
                                                   RasterizerState::CullMode cullMode,
                                                   bool wireFrame,
                                                   bool counterClockWise);
 
      COGSCORE_DLL_API uint16_t getRasterizerState(const RasterizerState & rs);
      Cogs::DepthStencilStateHandle getDepthStencilState(const DepthStencilState & ds);
      Cogs::SamplerStateHandle getSamplerState(const SamplerState & ss);
 
    private:
      IGraphicsDevice* device = nullptr;
      
      struct RasterizerStateInstance
      {
        uint16_t index = 0;
        Cogs::RasterizerStateHandle handle;
      };
 
      std::unordered_map<RasterizerState, RasterizerStateInstance> rasterizerStates;
      std::unordered_map<DepthStencilState, Cogs::DepthStencilStateHandle> depthStencilStates;
      std::unordered_map<SamplerState, Cogs::SamplerStateHandle> samplerStates;
    };
  }
}