Homework 5

.gitmodules

@@ -1,3 +1,12 @@
 [submodule "homeworks/homework_4/no_strings_attached/external/googletest"]
 	path = homeworks/homework_4/no_strings_attached/external/googletest
 	url = https://github.com/google/googletest.git
+[submodule "homeworks/homework_5/pixelator/external/ftxui"]
+	path = homeworks/homework_5/pixelator/external/ftxui
+	url = https://github.com/ArthurSonzogni/FTXUI.git
+[submodule "homeworks/homework_5/pixelator/external/googletest"]
+	path = homeworks/homework_5/pixelator/external/googletest
+	url = https://github.com/google/googletest.git
+[submodule "homeworks/homework_5/pixelator/external/stb"]
+	path = homeworks/homework_5/pixelator/external/stb
+	url = https://github.com/nothings/stb.git

homeworks/homework_5/pixelator/CMakeLists.txt

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+cmake_minimum_required(VERSION 3.16..3.24)
+project(pixelator VERSION 1
+  DESCRIPTION "Pixelate images in terminal"
+  LANGUAGES CXX)
+
+if(NOT CMAKE_BUILD_TYPE)
+  set(CMAKE_BUILD_TYPE Release CACHE STRING "" FORCE)
+endif()
+
+message(STATUS "CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
+
+# Create a pseudo-library to propagate the needed flags.
+add_library(cxx_setup INTERFACE)
+target_compile_options(cxx_setup INTERFACE -Wall -Wpedantic -Wextra)
+target_compile_features(cxx_setup INTERFACE cxx_std_17)
+target_include_directories(cxx_setup INTERFACE ${PROJECT_SOURCE_DIR})
+
+# Update the submodules here
+include(external/UpdateSubmodules.cmake)
+
+# Enable testing for this project
+include(CTest)
+
+# Add code in subdirectories
+add_subdirectory(external)
+add_subdirectory(${PROJECT_NAME})
+add_subdirectory(examples)

homeworks/homework_5/pixelator/examples/CMakeLists.txt

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+add_executable(use_ftxui use_ftxui.cpp)
+target_link_libraries(use_ftxui PRIVATE cxx_setup ftxui::screen)
+
+add_executable(use_stb_image use_stb_image.cpp)
+target_link_libraries(use_stb_image PRIVATE cxx_setup stb::stb)
+
+add_executable(pixelate pixelate.cpp)
+target_link_libraries(pixelate PRIVATE cxx_setup stb_image_data_view drawer pixelate_image)
+
+# TODO: Add your binaries here
+# There must be a binary `pixelate` here

homeworks/homework_5/pixelator/examples/pixelate.cpp

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+#include "pixelator/drawer.hpp"
+#include "pixelator/pixelate_image.hpp"
+#include "pixelator/stb_image_data_view.hpp"
+
+#include <cstddef>
+#include <filesystem>
+#include <utility>
+namespace {
+using pixelator::Drawer;
+using pixelator::PixelateImage;
+using pixelator::StbImageDataView;
+}  // namespace
+
+int main(int argc, char **argv) {
+  if (argc < 2) { std::cerr << "No image provided." << std::endl; }
+
+  StbImageDataView image{argv[1]};
+  if (image.empty()) {
+    std::cerr << "Image could not be loaded" << std::endl;
+    exit(1);
+  }
+
+  Drawer drawer{ftxui::Dimension::Full()};
+
+  drawer.Set(PixelateImage(image, drawer.size()));
+  drawer.Draw();
+  return 0;
+}

homeworks/homework_5/pixelator/examples/use_ftxui.cpp

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+#include "ftxui/screen/color.hpp"
+#include "ftxui/screen/screen.hpp"
+
+namespace {
+const ftxui::Color kYellowishColor = ftxui::Color::RGB(255, 200, 100);
+}
+
+int main() {
+  const ftxui::Dimensions dimensions{ftxui::Dimension::Full()};
+  ftxui::Screen screen{ftxui::Screen::Create(dimensions)};
+  auto &pixel_left = screen.PixelAt(10, 10);
+  pixel_left.background_color = kYellowishColor;
+  pixel_left.character = ' ';
+  auto &pixel_right = screen.PixelAt(11, 10);
+  pixel_right.background_color = kYellowishColor;
+  pixel_right.character = ' ';
+  screen.Print();
+  return 0;
+}

homeworks/homework_5/pixelator/examples/use_stb_image.cpp

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+// Make sure to have this in EXACTLY one cpp file
+// The best place for this is the cpp file of your library
+// that holds a class that wraps around the stb_image data
+// For more see here: https://github.com/nothings/stb#faq
+#define STB_IMAGE_IMPLEMENTATION
+#include "stb/stb_image.h"
+
+#include <filesystem>
+#include <iostream>
+
+namespace {
+static constexpr auto kLoadAllChannels{0};
+
+// A dummy color structure. Use ftxui::Color in actual code.
+struct Color {
+  int red;
+  int green;
+  int blue;
+};
+
+}  // namespace
+
+int main(int argc, char **argv) {
+  if (argc < 2) { std::cerr << "No image provided.\n"; }
+  const std::filesystem::path image_path{argv[1]};
+  if (!std::filesystem::exists(image_path)) {
+    std::cerr << "No image file: " << image_path << std::endl;
+    std::exit(1);
+  }
+
+  // Load the data
+  int rows{};
+  int cols{};
+  int channels{};
+  // This call also populates rows, cols, channels.
+  auto image_data{
+      stbi_load(image_path.c_str(), &cols, &rows, &channels, kLoadAllChannels)};
+  std::cout << "Loaded image of size: [" << rows << ", " << cols << "] with "
+            << channels << " channels\n";
+  if (!image_data) {
+    std::cerr << "Failed to load image data from file: " << image_path
+              << std::endl;
+    std::exit(1);
+  }
+
+  // The data is stored sequentially, in this order per pixel: red, green, blue,
+  // alpha This patterns repeats for every pixel of the image, so the resulting
+  // data layout is: [rgbargbargba...]
+  int query_row = 10;
+  int query_col = 15;
+  const auto index{channels * (query_row * cols + query_col)};
+  const Color color{
+      image_data[index], image_data[index + 1], image_data[index + 2]};
+  std::cout << "Color at pixel: [" << query_row << ", " << query_col
+            << "] =  RGB: (" << color.red << ", " << color.green << ", "
+            << color.blue << ")\n";
+
+  // We must explicitly free the memory allocated for this image.
+  // The reason for this is that stb_image is a C library,
+  // which has no classes and no RAII in the form about which we talked before.
+  // Now you see why people want to write C++ and not C? ;)
+  stbi_image_free(image_data);
+  return 0;
+}

homeworks/homework_5/pixelator/external/CMakeLists.txt

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+include(gtest.cmake)
+include(ftxui.cmake)
+include(stb.cmake)

homeworks/homework_5/pixelator/external/UpdateSubmodules.cmake

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+find_package(Git QUIET)
+
+if(GIT_FOUND)
+  option(UPDATE_SUBMODULES "Check submodules during build" ON)
+
+  if(NOT UPDATE_SUBMODULES)
+    return()
+  endif()
+
+  execute_process(COMMAND ${GIT_EXECUTABLE} submodule
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    OUTPUT_VARIABLE EXISTING_SUBMODULES
+    RESULT_VARIABLE RETURN_CODE)
+
+  message(STATUS "Updating git submodules:\n${EXISTING_SUBMODULES}")
+
+  execute_process(COMMAND ${GIT_EXECUTABLE} submodule update --init --recursive
+    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+    RESULT_VARIABLE RETURN_CODE)
+
+  if(NOT RETURN_CODE EQUAL "0")
+    message(WARNING "Cannot update submodules. Git command failed with ${RETURN_CODE}.")
+    return()
+  endif()
+
+  message(STATUS "Git submodules updated successfully.")
+endif()

homeworks/homework_5/pixelator/external/ftxui.cmake

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+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+add_subdirectory(ftxui)

homeworks/homework_5/pixelator/external/gtest.cmake

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+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_CXX_EXTENSIONS OFF)
+set(INSTALL_GTEST OFF)
+add_subdirectory(googletest)

homeworks/homework_5/pixelator/external/stb.cmake

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+add_library(stb INTERFACE)
+target_include_directories(stb INTERFACE ${PROJECT_SOURCE_DIR}/external/)
+if (NOT TARGET stb::stb)
+  add_library(stb::stb ALIAS stb)
+endif()

homeworks/homework_5/pixelator/pixelator/CMakeLists.txt

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+# TODO: Add your libraries here
+# You must have the following libraries:
+# - stb_image_data_view
+# - drawer
+# - image
+# - pixelate_image
+
+add_library(stb_image_data_view stb_image_data_view.cpp)
+target_link_libraries(stb_image_data_view PUBLIC cxx_setup stb::stb ftxui::screen)
+
+add_library(image image.cpp)
+target_link_libraries(image PUBLIC cxx_setup ftxui::screen stb_image_data_view)
+
+add_library(drawer drawer.cpp)
+target_link_libraries(drawer PUBLIC cxx_setup ftxui::screen image)
+
+add_library(pixelate_image INTERFACE)
+target_link_libraries(pixelate_image INTERFACE image stb_image_data_view)
+
+add_library(test_global_variables INTERFACE)
+target_link_libraries(test_global_variables INTERFACE image)
+
+
+if(BUILD_TESTING)
+  # TODO: Add your tests executable with all your tests here
+  # Name it pixelator_tests.
+  # Also use gtest_discover_tests(pixelator_tests)
+  # to register them with CTest
+  add_executable(pixelate_image_test pixelate_image_test.cpp)
+  target_link_libraries(pixelate_image_test PRIVATE pixelate_image test_global_variables GTest::gtest_main)
+
+  add_executable(drawer_test drawer_test.cpp)
+  target_link_libraries(drawer_test PRIVATE drawer GTest::gtest_main)
+
+  add_executable(image_test image_test.cpp)
+  target_link_libraries(image_test PRIVATE image GTest::gtest_main)
+
+  add_executable(stb_image_data_view_test stb_image_data_view_test.cpp)
+  target_link_libraries(stb_image_data_view_test PRIVATE stb_image_data_view test_global_variables GTest::gtest_main)
+
+  include(GoogleTest)
+  gtest_discover_tests(pixelate_image_test)
+  gtest_discover_tests(drawer_test)
+  gtest_discover_tests(image_test)
+  gtest_discover_tests(stb_image_data_view_test)
+endif()

homeworks/homework_5/pixelator/pixelator/drawer.cpp

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+#include "pixelator/drawer.hpp"
+#include <algorithm>
+#include <iostream>
+
+pixelator::Drawer::Drawer(const ftxui::Dimensions dimensions) {
+  if (dimensions.dimx == ftxui::Dimension::Full().dimx &&
+      dimensions.dimy == ftxui::Dimension::Full().dimy) {
+    rows_ = ftxui::Dimension::Full().dimx;
+    cols_ = ftxui::Dimension::Full().dimy;
+  } else {
+    rows_ = dimensions.dimx;
+    cols_ = rows_ * 2;
+  }
+  screen_ = ftxui::Screen::Create({rows_, cols_});
+}
+
+int pixelator::Drawer::rows() const { return rows_; }
+
+int pixelator::Drawer::cols() const { return cols_; }
+
+const pixelator::Size pixelator::Drawer::size() const {
+  return pixelator::Size{rows_, cols_};
+}
+
+void pixelator::Drawer::Set(pixelator::Image image) {
+  for (int i = 0; i < image.rows(); i++) {
+    for (int j = 0; j < image.cols(); j++) {
+      auto &pixel_left = screen_.PixelAt(j * 2, i);
+      pixel_left.background_color = image.at(i, j);
+      pixel_left.character = ' ';
+      auto &pixel_right = screen_.PixelAt(j * 2 + 1, i);
+      pixel_right.background_color = image.at(i, j);
+      pixel_right.character = ' ';
+    }
+  }
+
+  return;
+}
+
+void pixelator::Drawer::Draw() const {
+  screen_.Print();
+  return;
+}
+
+std::string pixelator::Drawer::ToString() const {
+  std::string string_image = screen_.ToString();
+
+  // Remove new line characters from the end of the string
+  // TODO: I added removing of the new line characters here since I was getting
+  // testing errors in github but not on local machine. I did not perform
+  // extensive test when I added this.
+  while (!string_image.empty() &&
+         (string_image[string_image.size() - 1] == '\r' ||
+          string_image[string_image.size() - 1] == '\n' ||
+          string_image[string_image.size() - 1] == ' ')) {
+    string_image.erase(string_image.size() - 1);
+  }
+
+  return string_image;
+}

homeworks/homework_5/pixelator/pixelator/drawer.hpp

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+#pragma once
+#include "ftxui/screen/color.hpp"
+#include "ftxui/screen/screen.hpp"
+#include "pixelator/image.hpp"
+namespace pixelator {
+class Drawer {
+private:
+  ftxui::Screen screen_{0, 0};
+  int rows_{};
+  int cols_{};
+
+public:
+  Drawer() = default;
+  Drawer(const ftxui::Dimensions dimensions);
+  int rows() const;
+  int cols() const;
+  const Size size() const;
+  void Set(pixelator::Image image);
+  void Draw() const;
+  std::string ToString() const;
+};
+} // namespace pixelator

homeworks/homework_5/pixelator/pixelator/drawer_test.cpp

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+#include "pixelator/drawer.hpp"
+#include <gtest/gtest.h>
+
+TEST(drawer_tests, test2) {
+  pixelator::Drawer full_screen_drawer{ftxui::Dimension::Full()};
+  pixelator::Drawer fixed_screen_drawer{ftxui::Dimension::Fixed(42)};
+
+  EXPECT_EQ(ftxui::Terminal::Size().dimx, full_screen_drawer.size().rows);
+  EXPECT_EQ(ftxui::Terminal::Size().dimy, full_screen_drawer.size().cols);
+
+  EXPECT_EQ(42, fixed_screen_drawer.size().rows);
+  EXPECT_EQ(84, fixed_screen_drawer.size().cols);
+}