AnimationAsset.h

#pragma once
 
#include "Engine/Core/Asset.h"
#include "Engine/Files/AssetPath.h"
 
#include <cstdint>
#include <glm/glm.hpp>
#include <glm/gtc/quaternion.hpp>
#include <string>
#include <vector>

namespace Engine::Animation
{

    enum class InterpolationType
    {
        LINEAR,  
        STEP,  
        CUBIC_SPLINE  
    };

    struct AnimationChannel
    {
        uint32_t jointIndex = 0;  
        enum class Path
        {
            TRANSLATION,  
            ROTATION,  
            SCALE  
        };
        Path path = Path::TRANSLATION;  
        InterpolationType      interpolation = InterpolationType::LINEAR;  
        std::vector<float>     timestamps;  
        std::vector<glm::vec4> values;  
    };
}  // namespace Engine::Animation
 
namespace Engine::Assets
{
    class Animation : public Asset::AssetBase
    {
    public:
        Animation();

        [[nodiscard]] float getDuration() const
        {
            return duration_;
        }

        [[nodiscard]] const std::string & getName() const
        {
            return name_;
        }

        [[nodiscard]] const std::vector<Engine::Animation::AnimationChannel> & getChannels() const
        {
            return channels_;
        }

        void sample(
            uint32_t    channelIndex,
            float       time,
            glm::vec3 & outTranslation,
            glm::quat & outRotation,
            glm::vec3 & outScale
        ) const;
 
        // TODO: check if these variables need to be public
        std::string name_;  
        float       duration_ = 0.0f;  
 
        std::vector<Engine::Animation::AnimationChannel> channels_;  
    };

    class AnimationAssetManager : public Asset::AssetManager<Asset::MeshPath, Animation>
    {
    public:
        AnimationAssetManager() = default;
    };
}  // namespace Engine::Assets