ForwardRenderTechnique.hpp

// Copyright (C) 2017 Jérôme Leclercq
// This file is part of the "Nazara Engine - Graphics module"
// For conditions of distribution and use, see copyright notice in Config.hpp

#pragma once

#ifndef NAZARA_FORWARDRENDERTECHNIQUE_HPP
#define NAZARA_FORWARDRENDERTECHNIQUE_HPP

#include <Nazara/Prerequesites.hpp>
#include <Nazara/Graphics/AbstractRenderTechnique.hpp>
#include <Nazara/Graphics/Config.hpp>
#include <Nazara/Graphics/ForwardRenderQueue.hpp>
#include <Nazara/Graphics/Light.hpp>
#include <Nazara/Renderer/Shader.hpp>
#include <Nazara/Utility/IndexBuffer.hpp>
#include <Nazara/Utility/VertexBuffer.hpp>

namespace Nz
{
    class NAZARA_GRAPHICS_API ForwardRenderTechnique : public AbstractRenderTechnique
    {
        public:
            ForwardRenderTechnique();
            ~ForwardRenderTechnique() = default;

            void Clear(const SceneData& sceneData) const override;
            bool Draw(const SceneData& sceneData) const override;

            unsigned int GetMaxLightPassPerObject() const;
            AbstractRenderQueue* GetRenderQueue() override;
            RenderTechniqueType GetType() const override;

            void SetMaxLightPassPerObject(unsigned int maxLightPassPerObject);

            static bool Initialize();
            static void Uninitialize();

        protected:
            struct ShaderUniforms;

            void ChooseLights(const Spheref& object, bool includeDirectionalLights = true) const;
            void DrawBasicSprites(const SceneData& sceneData, ForwardRenderQueue::Layer& layer) const;
            void DrawBillboards(const SceneData& sceneData, ForwardRenderQueue::Layer& layer) const;
            void DrawOpaqueModels(const SceneData& sceneData, ForwardRenderQueue::Layer& layer) const;
            void DrawOrderedSprites(const SceneData& sceneData, ForwardRenderQueue::Layer& layer) const;
            void DrawTransparentModels(const SceneData& sceneData, ForwardRenderQueue::Layer& layer) const;
            const ShaderUniforms* GetShaderUniforms(const Shader* shader) const;
            void OnShaderInvalidated(const Shader* shader) const;
            void SendLightUniforms(const Shader* shader, const LightUniforms& uniforms, unsigned int index, unsigned int lightIndex, unsigned int uniformOffset) const;

            static float ComputeDirectionalLightScore(const Spheref& object, const AbstractRenderQueue::DirectionalLight& light);
            static float ComputePointLightScore(const Spheref& object, const AbstractRenderQueue::PointLight& light);
            static float ComputeSpotLightScore(const Spheref& object, const AbstractRenderQueue::SpotLight& light);
            static bool IsDirectionalLightSuitable(const Spheref& object, const AbstractRenderQueue::DirectionalLight& light);
            static bool IsPointLightSuitable(const Spheref& object, const AbstractRenderQueue::PointLight& light);
            static bool IsSpotLightSuitable(const Spheref& object, const AbstractRenderQueue::SpotLight& light);

            struct LightIndex
            {
                LightType type;
                float score;
                unsigned int index;
            };

            struct ShaderUniforms
            {
                NazaraSlot(Shader, OnShaderUniformInvalidated, shaderUniformInvalidatedSlot);
                NazaraSlot(Shader, OnShaderRelease, shaderReleaseSlot);

                LightUniforms lightUniforms;
                bool hasLightUniforms;

                int lightOffset; // "Distance" between Lights[0].type and Lights[1].type

                // Other uniforms
                int eyePosition;
                int reflectionMap;
                int sceneAmbient;
                int textureOverlay;
            };

            mutable std::unordered_map<const Shader*, ShaderUniforms> m_shaderUniforms;
            mutable std::vector<LightIndex> m_lights;
            Buffer m_vertexBuffer;
            mutable ForwardRenderQueue m_renderQueue;
            Texture m_whiteTexture;
            VertexBuffer m_billboardPointBuffer;
            VertexBuffer m_spriteBuffer;
            unsigned int m_maxLightPassPerObject;

            static IndexBuffer s_quadIndexBuffer;
            static Texture s_dummyReflection;
            static TextureSampler s_reflectionSampler;
            static TextureSampler s_shadowSampler;
            static VertexBuffer s_quadVertexBuffer;
            static VertexDeclaration s_billboardInstanceDeclaration;
            static VertexDeclaration s_billboardVertexDeclaration;
    };
}

#include <Nazara/Graphics/ForwardRenderTechnique.inl>

#endif // NAZARA_FORWARDRENDERTECHNIQUE_HPP