Change colour_t to be a strongly typed structure

Make RGB default of `colour_t`
Distinguish RGB and ARGB colors by type and colour_traits
Add `_colour` and `_argb` colour user-defined literals
Add `OpenVic::utility::unreachable`

3 files changed, 20 insertions, 3 deletions

diff --git a/src/openvic-simulation/utility/BMP.cpp b/src/openvic-simulation/utility/BMP.cpp
index d4e7cf7..83d26c4 100644
--- a/src/openvic-simulation/utility/BMP.cpp
+++ b/src/openvic-simulation/utility/BMP.cpp
@@ -102,7 +102,7 @@ bool BMP::read_header() {
 	if (header.num_colours != 0 && header.bits_per_pixel > PALETTE_BITS_PER_PIXEL_LIMIT) {
 		Logger::error(
 			"Invalid BMP palette size: ", header.num_colours, " (should be 0 as bits per pixel is ", header.bits_per_pixel,
-			" > 8)"
+			" > ", PALETTE_BITS_PER_PIXEL_LIMIT, ")"
 		);
 		header_validated = false;
 	}
@@ -207,7 +207,7 @@ bool BMP::read_pixel_data() {
 		Logger::error("Failed to move to the pixel data in the BMP file!");
 		return false;
 	}
-	const size_t pixel_data_size = get_width() * get_height() * header.bits_per_pixel / 8;
+	const size_t pixel_data_size = get_width() * get_height() * header.bits_per_pixel / CHAR_BIT;
 	pixel_data.resize(pixel_data_size);
 	file.read(reinterpret_cast<char*>(pixel_data.data()), pixel_data_size);
 	if (file.fail()) {
diff --git a/src/openvic-simulation/utility/Getters.hpp b/src/openvic-simulation/utility/Getters.hpp
index a722071..1fb82b1 100644
--- a/src/openvic-simulation/utility/Getters.hpp
+++ b/src/openvic-simulation/utility/Getters.hpp
@@ -49,7 +49,10 @@ public: \
 ACCESS:
 
 namespace OpenVic {
-	struct ReturnByValueProperty {};
+	struct ReturnByValueProperty {
+		constexpr bool operator==(ReturnByValueProperty const&) const = default;
+		constexpr std::strong_ordering operator<=>(ReturnByValueProperty const&) const = default;
+	};
 
 	/*
 	 * Template function used to choose the return type and provide the implementation
diff --git a/src/openvic-simulation/utility/Utility.hpp b/src/openvic-simulation/utility/Utility.hpp
new file mode 100644
index 0000000..e8d7205
--- /dev/null
+++ b/src/openvic-simulation/utility/Utility.hpp
@@ -0,0 +1,14 @@
+#pragma once
+
+namespace OpenVic::utility {
+	[[noreturn]] inline void unreachable() {
+		// Uses compiler specific extensions if possible.
+		// Even if no extension is used, undefined behavior is still raised by
+		// an empty function body and the noreturn attribute.
+#ifdef __GNUC__ // GCC, Clang, ICC
+		__builtin_unreachable();
+#elif defined(_MSC_VER) // MSVC
+		__assume(false);
+#endif
+	}
+}