json_vec.h

#pragma once
 
#include <nlohmann/json.hpp>
#include <glm/glm.hpp>
#include <glm/gtc/quaternion.hpp>
 
#include "logger.h"
 
namespace Vkm::Engine::detail {
 
// GLM <-> flat JSON arrays. A null node returns the fallback silently (field
// omitted); a present but malformed one returns it with a warning.
 
inline nlohmann::json vec2ToJson(const glm::vec2& v) { return {v.x, v.y}; }
inline nlohmann::json vec3ToJson(const glm::vec3& v) { return {v.x, v.y, v.z}; }
inline nlohmann::json vec4ToJson(const glm::vec4& v) { return {v.x, v.y, v.z, v.w}; }
inline nlohmann::json quatToJson(const glm::quat& q) { return {q.w, q.x, q.y, q.z}; }
 
inline glm::vec2 jsonToVec2(const nlohmann::json& j, const glm::vec2& fallback = glm::vec2(0.0f)) {
    if (j.is_null()) return fallback;
    if (!j.is_array() || j.size() < 2) {
        LOG_WARNING_C(
            "IO",
            "jsonToVec2: expected a 2-element array, got '%s'; using fallback",
            j.dump().c_str()
        );
        return fallback;
    }
    return {j[0], j[1]};
}
inline glm::vec3 jsonToVec3(const nlohmann::json& j, const glm::vec3& fallback = glm::vec3(0.0f)) {
    if (j.is_null()) return fallback;
    if (!j.is_array() || j.size() < 3) {
        LOG_WARNING_C(
            "IO",
            "jsonToVec3: expected a 3-element array, got '%s'; using fallback",
            j.dump().c_str()
        );
        return fallback;
    }
    return {j[0], j[1], j[2]};
}
inline glm::vec4 jsonToVec4(const nlohmann::json& j, const glm::vec4& fallback = glm::vec4(0.0f)) {
    if (j.is_null()) return fallback;
    if (!j.is_array() || j.size() < 4) {
        LOG_WARNING_C(
            "IO",
            "jsonToVec4: expected a 4-element array, got '%s'; using fallback",
            j.dump().c_str()
        );
        return fallback;
    }
    return {j[0], j[1], j[2], j[3]};
}
inline glm::quat jsonToQuat(
    const nlohmann::json& j,
    const glm::quat& fallback = glm::quat(1.0f, 0.0f, 0.0f, 0.0f)
) {
    if (j.is_null()) return fallback;
    if (!j.is_array() || j.size() < 4) {
        LOG_WARNING_C(
            "IO",
            "jsonToQuat: expected a 4-element array, got '%s'; using fallback",
            j.dump().c_str()
        );
        return fallback;
    }
    return glm::quat(
        static_cast<float>(j[0]),
        static_cast<float>(j[1]),
        static_cast<float>(j[2]),
        static_cast<float>(j[3])
    );
}
 
} // namespace Vkm::Engine::detail