From d01d1090376739213766148cab7480c668ae3114 Mon Sep 17 00:00:00 2001
From: Yejneshwar <81953958+Yejneshwar@users.noreply.github.com>
Date: Wed, 4 Sep 2024 01:37:24 +0530
Subject: [PATCH] Ability to flush a GLB manifest to a stream (#143)

---
 GLTFSDK/Inc/GLTFSDK/GLBResourceWriter.h   |  3 +++
 GLTFSDK/Inc/GLTFSDK/GLTFResourceWriter.h  |  1 +
 GLTFSDK/Inc/GLTFSDK/PBRUtils.h            |  1 +
 GLTFSDK/Inc/GLTFSDK/ResourceReaderUtils.h |  1 +
 GLTFSDK/Source/GLBResourceWriter.cpp      | 14 ++++++++++++--
 GLTFSDK/Source/Validation.cpp             |  2 ++
 GLTFSDK/Source/Version.cpp                |  1 +
 7 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/GLTFSDK/Inc/GLTFSDK/GLBResourceWriter.h b/GLTFSDK/Inc/GLTFSDK/GLBResourceWriter.h
index 06f2a1e..19d9aa0 100644
--- a/GLTFSDK/Inc/GLTFSDK/GLBResourceWriter.h
+++ b/GLTFSDK/Inc/GLTFSDK/GLBResourceWriter.h
@@ -20,6 +20,9 @@ namespace Microsoft
             GLBResourceWriter(std::unique_ptr<IStreamWriterCache> streamCache);
             GLBResourceWriter(std::unique_ptr<IStreamWriterCache> streamCache, std::unique_ptr<std::iostream> tempBufferStream);
 
+            // Write to a stream instead of a file (can be useful for draco compression)
+            template <typename T>
+            void FlushStream(const std::string& manifest, T* stream);
             void Flush(const std::string& manifest, const std::string& uri);
             std::string GenerateBufferUri(const std::string& bufferId) const override;
             std::ostream* GetBufferStream(const std::string& bufferId) override;
diff --git a/GLTFSDK/Inc/GLTFSDK/GLTFResourceWriter.h b/GLTFSDK/Inc/GLTFSDK/GLTFResourceWriter.h
index 9c706d4..111826e 100644
--- a/GLTFSDK/Inc/GLTFSDK/GLTFResourceWriter.h
+++ b/GLTFSDK/Inc/GLTFSDK/GLTFResourceWriter.h
@@ -4,6 +4,7 @@
 #pragma once
 
 #include <GLTFSDK/ResourceWriter.h>
+#include <limits>
 
 #include <memory>
 
diff --git a/GLTFSDK/Inc/GLTFSDK/PBRUtils.h b/GLTFSDK/Inc/GLTFSDK/PBRUtils.h
index 3105c7d..c5a191a 100644
--- a/GLTFSDK/Inc/GLTFSDK/PBRUtils.h
+++ b/GLTFSDK/Inc/GLTFSDK/PBRUtils.h
@@ -5,6 +5,7 @@
 
 #include <GLTFSDK/Color.h>
 #include <GLTFSDK/ExtensionsKHR.h>
+#include <limits>
 
 namespace Microsoft
 {
diff --git a/GLTFSDK/Inc/GLTFSDK/ResourceReaderUtils.h b/GLTFSDK/Inc/GLTFSDK/ResourceReaderUtils.h
index b02a7c4..248c66c 100644
--- a/GLTFSDK/Inc/GLTFSDK/ResourceReaderUtils.h
+++ b/GLTFSDK/Inc/GLTFSDK/ResourceReaderUtils.h
@@ -8,6 +8,7 @@
 #include <string>
 #include <vector>
 #include <cmath>
+#include <limits>
 
 namespace Microsoft
 {
diff --git a/GLTFSDK/Source/GLBResourceWriter.cpp b/GLTFSDK/Source/GLBResourceWriter.cpp
index 9d3b934..4200098 100644
--- a/GLTFSDK/Source/GLBResourceWriter.cpp
+++ b/GLTFSDK/Source/GLBResourceWriter.cpp
@@ -4,6 +4,7 @@
 #include <GLTFSDK/GLBResourceWriter.h>
 
 #include <sstream>
+#include <fstream>
 
 using namespace Microsoft::glTF;
 
@@ -42,7 +43,8 @@ GLBResourceWriter::GLBResourceWriter(std::unique_ptr<IStreamWriterCache> streamC
 {
 }
 
-void GLBResourceWriter::Flush(const std::string& manifest, const std::string& uri)
+template <typename T>
+void GLBResourceWriter::FlushStream(const std::string& manifest, T* stream)
 {
     uint32_t jsonChunkLength = static_cast<uint32_t>(manifest.length());
     const uint32_t jsonPaddingLength = ::CalculatePadding(jsonChunkLength);
@@ -59,7 +61,6 @@ void GLBResourceWriter::Flush(const std::string& manifest, const std::string& ur
         + sizeof(binaryChunkLength) + GLB_CHUNK_TYPE_SIZE // 8 bytes (BIN header)
         + binaryChunkLength;
 
-    auto stream = m_streamWriterCache->Get(uri);
 
     // Write GLB header (12 bytes)
     StreamUtils::WriteBinary(*stream, GLB_HEADER_MAGIC_STRING, GLB_HEADER_MAGIC_STRING_SIZE);
@@ -96,6 +97,15 @@ void GLBResourceWriter::Flush(const std::string& manifest, const std::string& ur
     }
 }
 
+template void GLBResourceWriter::FlushStream<std::fstream>(const std::string& manifest, std::fstream* stream);
+template void GLBResourceWriter::FlushStream<std::stringstream>(const std::string& manifest, std::stringstream* stream);
+
+void GLBResourceWriter::Flush(const std::string& manifest, const std::string& uri)
+{
+    auto stream = m_streamWriterCache->Get(uri);
+    this->FlushStream<std::ostream>(manifest, stream.get());
+}
+
 std::string GLBResourceWriter::GenerateBufferUri(const std::string& bufferId) const
 {
     std::string bufferUri;
diff --git a/GLTFSDK/Source/Validation.cpp b/GLTFSDK/Source/Validation.cpp
index f081fac..d79df15 100644
--- a/GLTFSDK/Source/Validation.cpp
+++ b/GLTFSDK/Source/Validation.cpp
@@ -7,6 +7,8 @@
 
 #include <sstream>
 
+#include <limits>
+
 using namespace Microsoft::glTF;
 
 namespace
diff --git a/GLTFSDK/Source/Version.cpp b/GLTFSDK/Source/Version.cpp
index 87a5315..0db0593 100644
--- a/GLTFSDK/Source/Version.cpp
+++ b/GLTFSDK/Source/Version.cpp
@@ -8,6 +8,7 @@
 #include <set>
 #include <regex>
 #include <sstream>
+#include <limits>
 
 using namespace Microsoft::glTF;