chore: write gltf header with new writers and outputs

src/ObjWriting/XModel/Gltf/GltfWriter.cpp

@@ -0,0 +1,45 @@
+#include "GltfWriter.h"
+
+#include "GitVersion.h"
+#include "XModel/Gltf/GltfConstants.h"
+#include "XModel/Gltf/JsonGltf.h"
+
+using namespace gltf;
+using namespace nlohmann;
+
+namespace
+{
+    constexpr auto GLTF_GENERATOR = "OpenAssetTools " GIT_VERSION;
+
+    class GltfWriterImpl final : public gltf::Writer
+    {
+    public:
+        GltfWriterImpl(const Output* output, std::string gameName, std::string zoneName)
+            : m_output(output),
+              m_game_name(std::move(gameName)),
+              m_zone_name(std::move(zoneName))
+        {
+        }
+
+        void Write(std::ostream& stream) override
+        {
+            JsonRoot gltf;
+            gltf.asset.version = GLTF_VERSION_STRING;
+            gltf.asset.generator = GLTF_GENERATOR;
+
+            const json jRoot = gltf;
+            m_output->EmitJson(jRoot);
+            m_output->Finalize();
+        }
+
+    private:
+        const Output* m_output;
+        std::string m_game_name;
+        std::string m_zone_name;
+    };
+} // namespace
+
+std::unique_ptr<Writer> Writer::CreateWriter(const Output* output, std::string gameName, std::string zoneName)
+{
+    return std::make_unique<GltfWriterImpl>(output, std::move(gameName), std::move(zoneName));
+}