Add basic pfm support

openVulkanoCpp/IO/Files/Pfm.hpp

@@ -0,0 +1,97 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#pragma once
+
+#include "Base/Utils.hpp"
+#include <inttypes.h>
+#include <string>
+#include <sstream>
+#include <iomanip>
+#include <memory>
+
+namespace openVulkanoCpp
+{
+	//TODO handle comments
+	class PfmHeader
+	{
+	public:
+		static constexpr std::string_view FILE_TYPE = "PFM";
+		static constexpr std::string_view FILE_EXT = ".pfm";
+
+		uint32_t width, height;
+		float maxValue;
+		bool color, littleEndian;
+
+		PfmHeader() : width(0), height(0), maxValue(0), color(false), littleEndian(Utils::IsLittleEndian()) {}
+
+		PfmHeader(uint32_t width, uint32_t height, float maxValue, bool color) :
+				width(width), height(height), maxValue(maxValue), color(color), littleEndian(Utils::IsLittleEndian())
+		{}
+
+		constexpr PfmHeader(uint32_t width, uint32_t height, float maxValue, bool color, bool littleEndian) :
+				width(width), height(height), maxValue(maxValue), color(color), littleEndian(littleEndian)
+		{}
+
+		std::string ToString() const
+		{
+			std::stringstream headerStream;
+			headerStream << *this;
+			return headerStream.str();
+		}
+
+		friend std::ostream& operator<< (std::ostream& outStream, const PfmHeader& pfmHeader)
+		{
+			outStream << (pfmHeader.color ? "PF" : "Pf") << '\n';
+			outStream << pfmHeader.width << ' ' << pfmHeader.height << '\n';
+			if (pfmHeader.littleEndian) outStream << '-';
+			outStream << std::fixed << std::setprecision(1) << pfmHeader.maxValue << '\n';
+			return outStream;
+		}
+
+		friend std::istream& operator>> (std::istream& inStream, PfmHeader& pfmHeader)
+		{
+			std::string marker;
+			inStream >> marker;
+			if (marker == "PF") pfmHeader.color = true;
+			else if (marker == "Pf") pfmHeader.color = false;
+			else throw std::runtime_error("Malformed PFM header!");
+			inStream >> pfmHeader.width >> pfmHeader.height;
+			inStream >> pfmHeader.maxValue;
+			if (pfmHeader.maxValue < 0)
+			{
+				pfmHeader.maxValue *= -1;
+				pfmHeader.littleEndian = true;
+			}
+			else
+			{
+				pfmHeader.littleEndian = false;
+			}
+			return inStream;
+		}
+
+		constexpr size_t GetImageSize() const
+		{
+			size_t size = height * width * sizeof(float);
+			if (color) size *= 3;
+			return size;
+		}
+
+		static std::pair<PfmHeader, std::unique_ptr<float[]>> ReadImage(std::istream& inStream)
+		{
+			std::pair<PfmHeader, std::unique_ptr<float[]>> image;
+			inStream >> image.first;
+
+			if (Utils::IsLittleEndian() != image.first.littleEndian)
+				throw std::runtime_error("Conversion support for endianness not implemented");
+
+			size_t size = image.first.height * image.first.width;
+			image.second = std::make_unique<float[]>(size);
+			inStream.read(reinterpret_cast<char*>(image.second.get()), size);
+			return image;
+		};
+	};
+}