cup_edit/thermion_dart/native/include/FilamentViewer.hpp

#pragma once

#include <filament/Camera.h>
#include <filament/Frustum.h>
#include <filament/ColorGrading.h>
#include <filament/Engine.h>
#include <filament/IndexBuffer.h>
#include <filament/RenderableManager.h>
#include <filament/Renderer.h>
#include <filament/Scene.h>
#include <filament/Skybox.h>
#include <filament/TransformManager.h>
#include <filament/VertexBuffer.h>
#include <filament/View.h>
#include <filament/LightManager.h>

#include <gltfio/AssetLoader.h>
#include <gltfio/FilamentAsset.h>
#include <gltfio/ResourceLoader.h>

#include <camutils/Manipulator.h>

#include <utils/NameComponentManager.h>

#include <math/vec3.h>
#include <math/vec4.h>
#include <math/mat3.h>
#include <math/norm.h>

#include <fstream>
#include <iostream>
#include <string>
#include <chrono>

#include "ResourceBuffer.hpp"
#include "scene/SceneManager.hpp"
#include "ThreadPool.hpp"

namespace thermion
{

    typedef std::chrono::time_point<std::chrono::high_resolution_clock> time_point_t;

    using namespace std::chrono;
    using namespace gltfio;
    using namespace camutils;

    class FilamentViewer
    {

        typedef int32_t EntityId;

    public:
        FilamentViewer(const void *context, const ResourceLoaderWrapperImpl *const resourceLoaderWrapper, void *const platform = nullptr, const char *uberArchivePath = nullptr);
        ~FilamentViewer();

        View* createView();
        View* getViewAt(int index);

        void loadSkybox(const char *const skyboxUri);
        void removeSkybox();

        void loadIbl(const char *const iblUri, float intensity);
        void removeIbl();
        void rotateIbl(const math::mat3f &matrix);
        void createIbl(float r, float g, float b, float intensity);

        void render(
            uint64_t frameTimeInNanos
        );
        void setFrameInterval(float interval);

        void setMainCamera(View *view);
        EntityId getMainCamera();
        Camera* getCamera(EntityId entity);
        
        float getCameraFov(bool horizontal);
        void setCameraFov(double fovDegrees, bool horizontal);

        SwapChain* createSwapChain(const void *surface);
        SwapChain* createSwapChain(uint32_t width, uint32_t height);
        void destroySwapChain(SwapChain* swapChain);

        RenderTarget* createRenderTarget(intptr_t textureId, uint32_t width, uint32_t height);
        void destroyRenderTarget(RenderTarget* renderTarget);

        Renderer *getRenderer();

        std::map<SwapChain*, std::vector<View*>> _renderable;
        
        void setRenderable(View* view, SwapChain* swapChain, bool renderable);

        void setBackgroundColor(const float r, const float g, const float b, const float a);
        void setBackgroundImage(const char *resourcePath, bool fillHeight, uint32_t width, uint32_t height);
        void clearBackgroundImage();
        void setBackgroundImagePosition(float x, float y, bool clamp, uint32_t width, uint32_t height);
        
        Engine* getEngine() { 
            return _engine;
        }

        EntityId addLight(
            LightManager::Type t, 
            float colour, 
            float intensity, 
            float posX, 
            float posY, 
            float posZ, 
            float dirX, 
            float dirY, 
            float dirZ, 
            float falloffRadius,
            float spotLightConeInner,
            float spotLightConeOuter,
            float sunAngularRadius,
            float sunHaloSize,
            float sunHaloFallof,
            bool shadows);
        void setLightPosition(EntityId entityId, float x, float y, float z);
        void setLightDirection(EntityId entityId, float x, float y, float z);
        void removeLight(EntityId entityId);
        void clearLights();

        void capture(View* view, uint8_t *out, bool useFence, SwapChain* swapChain, void (*onComplete)());
        void capture(View* view, uint8_t *out, bool useFence, SwapChain* swapChain, RenderTarget* renderTarget, void (*onComplete)());

        SceneManager *const getSceneManager()
        {
            return (SceneManager *const)_sceneManager;
        }

        SwapChain* getSwapChainAt(int index) {
            if(index < _swapChains.size()) {
                return _swapChains[index];
            }
            Log("Error: index %d is greater than available swapchains", index);
            return nullptr;
        }

        void unprojectTexture(EntityId entity, uint8_t* input, uint32_t inputWidth, uint32_t inputHeight, uint8_t* out, uint32_t outWidth, uint32_t outHeight);  

    private:
        const ResourceLoaderWrapperImpl *const _resourceLoaderWrapper;
        Scene *_scene = nullptr;
        Engine *_engine = nullptr;
        thermion::ThreadPool *_tp = nullptr;
        Renderer *_renderer = nullptr;
        SceneManager *_sceneManager = nullptr;
        std::vector<RenderTarget*> _renderTargets;
        std::vector<SwapChain*> _swapChains;
        std::vector<View*> _views;

        std::mutex _renderMutex; // mutex to ensure thread safety when removing assets

        std::vector<utils::Entity> _lights;
        Texture *_skyboxTexture = nullptr;
        Skybox *_skybox = nullptr;
        Texture *_iblTexture = nullptr;
        IndirectLight *_indirectLight = nullptr;

        float _frameInterval = 1000.0 / 60.0;

        // Camera properties
        Camera *_mainCamera = nullptr; // the default camera added to every scene. If you want the *active* camera, access via View.
        
        // background image properties
        uint32_t _imageHeight = 0;
        uint32_t _imageWidth = 0;
        filament::math::mat4f _imageScale;
        Texture *_imageTexture = nullptr;
        Texture *_dummyImageTexture = nullptr;
        utils::Entity _imageEntity;
        VertexBuffer *_imageVb = nullptr;
        IndexBuffer *_imageIb = nullptr;
        Material *_imageMaterial = nullptr;
        TextureSampler _imageSampler;
        void loadKtx2Texture(std::string path, ResourceBuffer data);
        void loadKtxTexture(std::string path, ResourceBuffer data);
        void loadPngTexture(std::string path, ResourceBuffer data);
        void loadTextureFromPath(std::string path);
        void savePng(void *data, size_t size, int frameNumber);
        void createBackgroundImage();

        
        time_point_t _fpsCounterStartTime = std::chrono::high_resolution_clock::now();


        std::mutex _imageMutex;
        double _cumulativeAnimationUpdateTime = 0;
        int _frameCount = 0;
        int _skippedFrames = 0;
    };

    struct FrameCallbackData
    {
        FilamentViewer *viewer;
        uint32_t frameNumber;
    };

}