Add Vec (Part 1) (#2)

- Add `src` to include path.
- Replace ad-hoc arrays with `Vec`s.

Author: karnkaul

tray/CMakeLists.txt

@@ -1,5 +1,6 @@
 add_executable(${PROJECT_NAME})
 target_sources(${PROJECT_NAME} PRIVATE src/main.cpp)
+target_include_directories(${PROJECT_NAME} PRIVATE src)
 
 if(CMAKE_CXX_COMPILER_ID STREQUAL Clang OR CMAKE_CXX_COMPILER_ID STREQUAL GNU)
   target_compile_options(${PROJECT_NAME} PRIVATE

tray/src/main.cpp

@@ -1,29 +1,30 @@
+#include <tray/vec.hpp>
 #include <array>
 #include <cassert>
 #include <iostream>
 #include <ostream>
 #include <span>
 
+using namespace tray;
+
 namespace {
-struct Rgb {
-	std::array<std::uint8_t, 3> values{};
-};
+struct Rgb : Vec<std::uint8_t, 3> {};
 
 struct ImageData {
 	std::span<Rgb const> data{};
-	std::array<std::uint32_t, 2> extent{};
+	uvec2 extent{};
 };
 
 std::ostream& operator<<(std::ostream& out, ImageData const& image) {
-	assert(image.data.size() == image.extent[0] * image.extent[1]);
+	assert(image.data.size() == image.extent.x() * image.extent.y());
 	// write header
-	out << "P3\n" << image.extent[0] << ' ' << image.extent[1] << "\n255\n";
+	out << "P3\n" << image.extent.x() << ' ' << image.extent.y() << "\n255\n";
 	// write each row
-	for (std::uint32_t row = 0; row < image.extent[1]; ++row) {
+	for (std::uint32_t row = 0; row < image.extent.y(); ++row) {
 		// write each column
-		for (std::uint32_t col = 0; col < image.extent[0]; ++col) {
+		for (std::uint32_t col = 0; col < image.extent.x(); ++col) {
 			// compute index
-			auto const index = row * image.extent[0] + col;
+			auto const index = row * image.extent.x() + col;
 			// obtain corresponding Rgb
 			auto const& rgb = image.data[index];
 			// write out each channel
@@ -36,9 +37,9 @@ std::ostream& operator<<(std::ostream& out, ImageData const& image) {
 } // namespace
 
 int main() {
-	static constexpr auto extent = std::array{40U, 30U};
-	static constexpr auto white_v = Rgb{.values = {0xff, 0xff, 0xff}};
-	auto buffer = std::array<Rgb, extent[0] * extent[1]>{};
+	static constexpr auto extent = uvec2{40U, 30U};
+	static constexpr auto white_v = Rgb{0xff, 0xff, 0xff};
+	auto buffer = std::array<Rgb, extent.x() * extent.y()>{};
 	std::fill_n(buffer.data(), buffer.size(), white_v);
 	auto const image_data = ImageData{.data = buffer, .extent = extent};
 	std::cout << image_data;

tray/src/tray/vec.hpp

@@ -0,0 +1,25 @@
+#pragma once
+#include <array>
+#include <cstdint>
+
+namespace tray {
+template <typename Type, std::size_t Dim>
+struct Vec {
+	std::array<Type, Dim> values{};
+
+	constexpr Type& x() { return values[0]; }
+	constexpr Type const& x() const { return values[0]; }
+	constexpr Type& y() requires(Dim > 1) { return values[1]; }
+	constexpr Type const& y() const requires(Dim > 1) { return values[1]; }
+	constexpr Type& z() requires(Dim > 2) { return values[2]; }
+	constexpr Type const& z() const requires(Dim > 2) { return values[2]; }
+};
+
+using fvec2 = Vec<float, 2>;
+using uvec2 = Vec<std::uint32_t, 2>;
+using ivec2 = Vec<std::int32_t, 2>;
+
+using fvec3 = Vec<float, 3>;
+using uvec3 = Vec<std::uint32_t, 3>;
+using ivec3 = Vec<std::int32_t, 3>;
+} // namespace tray