break map reader into its own class

src/tmxmap.cpp

@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: Zlib
+// SPDX-FileCopyrightText: (c) 2015-2024 a dinosaur
+
+#include "tmxmap.hpp"
+#include "base64.h"
+#ifdef USE_ZLIB
+# include <zlib.h>
+#else
+# include "gzip.hpp"
+#endif
+#include <sstream>
+#include <fstream>
+
+
+bool TmxMap::Decode(std::span<uint32_t> out, const std::string_view base64)
+{
+	// Cut leading & trailing whitespace (including newlines)
+	auto beg = std::find_if_not(base64.begin(), base64.end(), ::isspace);
+	if (beg == std::end(base64))
+		return false;
+	auto end = std::find_if_not(base64.rbegin(), base64.rend(), ::isspace);
+	std::size_t begOff = std::distance(base64.begin(), beg);
+	std::size_t endOff = std::distance(end, base64.rend()) - begOff;
+	const auto trimmed = base64.substr(begOff, endOff);
+
+	// Decode base64 string
+	std::string decoded = base64_decode(trimmed);
+
+	// Decompress compressed data
+	auto dstSize = static_cast<uLongf>(sizeof(uint32_t) * out.size());
+	int res = uncompress(
+		reinterpret_cast<unsigned char*>(out.data()),
+		&dstSize,
+		reinterpret_cast<const unsigned char*>(decoded.data()),
+		static_cast<uLong>(decoded.size()));
+
+	return res >= 0;
+}
+
+void TmxMap::ReadTileset(rapidxml::xml_node<>* aXNode)
+{
+	std::string_view name, source;
+	uint32_t firstGid = 0, lastGid = 0;
+
+	// Read name
+	auto xAttrib = aXNode->first_attribute("name");
+	if (xAttrib != nullptr)
+		name = xAttrib->value();
+
+	// Read source
+	xAttrib = aXNode->first_attribute("source");
+	if (xAttrib != nullptr)
+		source = xAttrib->value();
+
+	// Read first global ID
+	xAttrib = aXNode->first_attribute("firstgid");
+	if (xAttrib != nullptr)
+		firstGid = static_cast<uint32_t>(std::stoul(xAttrib->value()));
+
+	// Read last global ID
+	xAttrib = aXNode->first_attribute("lastgid");
+	if (xAttrib)
+		lastGid = static_cast<uint32_t>(std::stoul(xAttrib->value()));
+
+	mTilesets.emplace_back(TmxTileset(name, source, firstGid, lastGid));
+}
+
+void TmxMap::ReadLayer(rapidxml::xml_node<>* aXNode)
+{
+	std::string_view name;
+	int width = 0, height = 0;
+
+	// Read name
+	auto xAttrib = aXNode->first_attribute("name");
+	if (xAttrib != nullptr)
+		name = xAttrib->value();
+
+	// Read width
+	xAttrib = aXNode->first_attribute("width");
+	if (xAttrib != nullptr)
+		width = std::stoi(xAttrib->value());
+
+	// Read height
+	xAttrib = aXNode->first_attribute("height");
+	if (xAttrib != nullptr)
+		height = std::stoi(xAttrib->value());
+
+	// Read tile data
+	auto xData = aXNode->first_node("data");
+	if (xData == nullptr)
+		return;
+
+	// TODO: don't assume base64
+	std::vector<uint32_t> tileDat(width * height);
+	if (!Decode(tileDat, xData->value()))
+		return;
+
+	mLayers.emplace_back(TmxLayer(width, height, name, std::move(tileDat)));
+}
+
+void TmxMap::ReadObjects(rapidxml::xml_node<>* aXNode)
+{
+	for (auto xNode = aXNode->first_node(); xNode != nullptr; xNode = xNode->next_sibling())
+	{
+		if (strcmp(xNode->name(), "object") != 0)
+			continue;
+
+		std::string_view name;
+		float x = 0.0f, y = 0.0f;
+
+		// Read name
+		auto xAttrib = xNode->first_attribute("name");
+		if (xAttrib != nullptr)
+			name = xAttrib->value();
+
+		// Read X pos
+		xAttrib = xNode->first_attribute("x");
+		if (xAttrib != nullptr)
+			x = std::stof(xAttrib->value());
+
+		// Read Y pos
+		xAttrib = xNode->first_attribute("y");
+		if (xAttrib != nullptr)
+			y = std::stof(xAttrib->value());
+
+		mObjects.emplace_back(TmxObject(name, x, y));
+	}
+}
+
+bool TmxMap::Load(const std::string_view inPath)
+{
+	// Read file into a buffer
+	auto inFile = std::ifstream(inPath);
+	std::stringstream buf;
+	buf << inFile.rdbuf();
+	std::string strXml = buf.str();
+	buf.clear();
+
+	// Parse document
+	rapidxml::xml_document<> xDoc;
+	xDoc.parse<0>(const_cast<char*>(strXml.c_str()));
+
+	// Get map node
+	auto xMap = xDoc.first_node("map");
+	if (xMap == nullptr)
+		return false;
+
+	// Read map attribs
+	rapidxml::xml_attribute<>* xAttrib = nullptr;
+	if ((xAttrib = xMap->first_attribute("width")) != nullptr)
+		mWidth = std::stoi(xAttrib->value());
+	if ((xAttrib = xMap->first_attribute("height")) != nullptr)
+		mHeight = std::stoi(xAttrib->value());
+
+	// Read nodes
+	for (auto xNode = xMap->first_node(); xNode != nullptr; xNode = xNode->next_sibling())
+	{
+		// Read layer nodes
+		const auto xName = xNode->name();
+		if (std::strcmp(xName, "layer") == 0)
+			ReadLayer(xNode);
+		else if (std::strcmp(xName, "tileset") == 0)
+			ReadTileset(xNode);
+		else if (std::strcmp(xName, "objectgroup") == 0)
+			ReadObjects(xNode);
+	}
+
+	return true;
+}