chore: add output implementations for gltf and glb

src/ObjWriting/XModel/Gltf/GltfTextOutput.cpp

@@ -0,0 +1,48 @@
+#include "GltfTextOutput.h"
+
+#include "Utils/Alignment.h"
+#include "XModel/Gltf/GltfConstants.h"
+
+#include <iomanip>
+#include <nlohmann/json.hpp>
+#include <tomcrypt.h>
+
+using namespace gltf;
+
+TextOutput::TextOutput(std::ostream& stream)
+    : m_stream(stream)
+{
+}
+
+std::optional<std::string> TextOutput::CreateBufferUri(const void* buffer, const size_t bufferSize) const
+{
+    static constexpr auto URI_PREFIX_LENGTH = std::char_traits<char>::length(GLTF_DATA_URI_PREFIX);
+    const auto base64Length = utils::Align(4u * (bufferSize / 3u), 4u);
+    const auto base64BufferSize = URI_PREFIX_LENGTH + base64Length;
+
+    std::string output(base64BufferSize, '\0');
+
+    std::memcpy(output.data(), &GLTF_DATA_URI_PREFIX, URI_PREFIX_LENGTH);
+
+    unsigned long outLength = base64Length;
+    base64_encode(static_cast<const unsigned char*>(buffer), bufferSize, &output[URI_PREFIX_LENGTH], &outLength);
+
+    assert(outLength == base64Length);
+
+    return output;
+}
+
+void TextOutput::EmitJson(const nlohmann::json& json) const
+{
+    m_stream << std::setw(4) << json;
+}
+
+void TextOutput::EmitBuffer(const void* buffer, const size_t bufferSize) const
+{
+    // Nothing to do
+}
+
+void TextOutput::Finalize() const
+{
+    // Nothing to do
+}