Update cpp/sdl-cmake example

+ Clean CMakeLists of unused options
+ Reorganize the linking of SDL to custom lib-sdl-test library
+ Improve Shape and Rectangle to better utilize inheritance

cpp/sdl-cmake/CMakeLists.txt

@@ -1,26 +1,22 @@
 ###############################################################################
 ## Author: Shaun Reed                                                        ##
-## Legal: All Content (c) 2019 Shaun Reed, all rights reserved               ##
+## Legal: All Content (c) 2021 Shaun Reed, all rights reserved               ##
 ##                                                                           ##
 ## Contact: shaunrd0@gmail.com  | URL: www.shaunreed.com | GitHub: shaunrd0  ##
 ##############################################################################
-# Root CMakeLists.txt of cpp practice 4-inheritance
+#
 
 # Define CMake version
 cmake_minimum_required(VERSION 3.15)
 
-project(       # Define project
+project(
-  inheritance  # Project name
+    #[[NAME]]    SDL-Cmake
-  DESCRIPTION  "Example project for class inheritance"
+    DESCRIPTION  "Example project for building SDL projects with CMake"
     LANGUAGES    CXX
 )
 
-# Pass this to program to control debug output
+# Add Library
-option (DB_CONF "Should we debug and configure files with cmake values?" ON)
+add_library(
-option (DB_BUILD "Should we run the build in debug mode?" OFF)
-option (EXE_BUILD "Should we build the executable?" ON)
-
-add_library(             # Add Library
     lib-sdl-test            # Library Name
     "src/lib-sdl-test.cpp"  # Sources..
     "src/lib-sdl-test.h"
@@ -28,43 +24,36 @@ add_library(             # Add Library
 
 target_include_directories(            # When calling library, include a directory
     lib-sdl-test                       # Library name
-  PUBLIC                           #
+    PUBLIC                             # Visibility
-    "${CMAKE_CURRENT_SOURCE_DIR}"  # Source directory of exe including our library
+    "${CMAKE_CURRENT_SOURCE_DIR}/src"  # Source directory for library
     )
 
-if (EXE_BUILD)
+# Search for SDL2 package
-  set(BUILD_STATUS "Building default executable")
+find_package(SDL2 REQUIRED sdl2)
-  include(FindPkgConfig)
-  pkg_search_module(SDL2 REQUIRED sdl2)
-  include_directories(${SDL2_INCLUDE_DIRS})
 
-  add_executable(         # Creating executable
+# If SDL2 was found successfully, link to lib-sdl-test
+if (SDL2_FOUND)
+  # Any target that links with this library will also link to SDL2
+  # + Because we choose PUBLIC visibility
+  target_include_directories(lib-sdl-test PUBLIC ${SDL2_INCLUDE_DIRS})
+  target_link_libraries(lib-sdl-test PUBLIC "${SDL2_LIBRARIES}")
+
+  # Creating executable
+  add_executable(
       sdl-test              # Exe name
       "apps/sdl-test.cpp"   # Exe Source(s)
   )
-  target_link_libraries(  # Linking the exe to library
+
+  # Linking the exe to library
+  target_link_libraries(
       sdl-test              # Executable to link
-    PRIVATE               #
+      PRIVATE               # Visibility
       lib-sdl-test          # Library to link
-      ${SDL2_LIBRARIES}
   )
-elseif(DB_BUILD)
-  set(BUILD_STATUS "Building in debug mode")
 
-  # Create compile_commands.json for linter
+else()
-  set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+  message(
-
+      "Error: CMake was unable to find SDL2 package.\n"
-  target_compile_definitions(inherited PRIVATE BUILD_STATUS=${BUILD_STATUS})
+      "Please install the libsdl2-dev package and try again.\n"
-elseif(DB_CONF)
+  )
-  set(BUILD_STATUS "Building in debug mode, configuring files")
-
-  # Configure header file with CMake variables defined in src/lib-inherit.h.in
-  # @ONLY is specified, only variables of the form @VAR@ will be replaced and ${VAR} will be ignored.
-  # configure_file(src/lib-inherit.h src/lib-inherit.h @ONLY)
-  configure_file(apps/sdl-test.cpp apps/sdl-test.cpp @ONLY)
- 
-  # Create compile_commands.json for linter
-  set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 endif()
-#target_compile_definitions(inherited PRIVATE BUILD_STATUS=${BUILD_STATUS})
-

cpp/sdl-cmake/apps/sdl-test.cpp

@@ -9,9 +9,8 @@
 ## apps/inherited.cpp
 */
 
-#include <src/lib-sdl-test.h>
+#include <lib-sdl-test.h>
 #include <iostream>
-//#include <string>
 
 int main (int argc, char const * argv[]) {
   // Cast cli arguments to void since they are unused in this exe
@@ -19,19 +18,26 @@ int main (int argc, char const * argv[]) {
   (void)argv;
 
   // Ensure SDL is initialized before continuing
- 	if (SDL_Init(SDL_INIT_EVERYTHING) < 0)
+  if (SDL_Init(SDL_INIT_EVERYTHING) < 0) exit(2);
-    exit(2);  
 
   SDL_Window *window;
   SDL_Renderer *renderer;
 
-  if (InitScreen(window, renderer) < 0)
+  if (InitScreen(window, renderer) < 0) {
     std::cout << "Error - Unable to initialize SDL screen\n";
+  }
 
+  // Draw a window for 3000ms
   DrawDelay(renderer, 3000);
+  // Destroy the window after 3 seconds
+  SDL_DestroyWindow(window);
+  // Destroy the renderer, since we won't be using it anymore
+  SDL_DestroyRenderer(renderer);
 
-  std::cout << "Test\n";
+  std::cout << "Testing creation of Shape, Rectangle...\n";
+  // Create a custom shape, and a default shape
   Shape shape(4,4), dShape;
+  // Create a custom rectangle, and a default rectangle
   Rectangle rect(4,8), dRect;
   std::cout << dShape.PrintInfo() << std::endl;
   std::cout << shape.PrintInfo() << std::endl;

cpp/sdl-cmake/src/lib-sdl-test.cpp

@@ -4,45 +4,22 @@
 ##                                                                           ##
 ## Contact: shaunrd0@gmail.com  | URL: www.shaunreed.com | GitHub: shaunrd0  ##
 ##############################################################################
-## src/lib-inherit.cpp
+##
 */
 
-#include <src/lib-sdl-test.h>
+#include <lib-sdl-test.h>
 
-// Shape class definitions
 
-Shape::Shape(double w, double h) {
+/******************************************************************************/
-  height = h;
+// Shape base class definitions
-  width = w;
+std::string Shape::PrintInfo() {
+  return name + " HxW: " + std::to_string(height) + "x" + std::to_string(width);
 };
 
-Shape::Shape() {
-  height = 2;
-  width = 2;
-};
 
-Shape::~Shape() { /* Shape destructor */};
+/******************************************************************************/
+// SDL helper function definitions
 
-const std::string Shape::PrintInfo() {
-  info = name + " HxW: " + std::to_string(height) + "x" + std::to_string(width);
-  return info;
-};
-
-// Rectangle Class definitions
-
-Rectangle::Rectangle(double w, double h) {
-  height = h;
-  width = w;
-};
-
-Rectangle::Rectangle() {
-  height = 2;
-  width = 4;
-};
-
-Rectangle::~Rectangle() { /* Rectangle destructor */ };
-
-/// SDL Helper Definitions
 int InitScreen(SDL_Window* &window, SDL_Renderer* &renderer) {
   int state = 0;
 
@@ -66,6 +43,5 @@ void DrawDelay(SDL_Renderer* renderer, int delay) {
 	SDL_RenderPresent(renderer);
   // Wait 3000ms, then continue
 	SDL_Delay(delay);
-
   return;
 }

cpp/sdl-cmake/src/lib-sdl-test.h

@@ -10,33 +10,42 @@
 #include <iostream>
 #include <string>
 #include <SDL2/SDL.h>
+#include <utility>
 #include <vector>
 
+
 class Shape {
+public:
+  // Provide ctor to set name of derived shape
+  Shape(double w, double h, std::string name_) :
+      width(w), height(h), name(std::move(name_)) {}
+  Shape(double w, double h) : width(w), height(h) {}
+  Shape() : width(2), height(2) {}
+  virtual ~Shape() = default;
+
+  // All derived inherit ability to show name
+  virtual std::string PrintInfo();
+
   private:
     double width, height;
-    std::string info;
     const std::string name = "Shape";
-
-  public:
-    Shape(double w, double h);
-    Shape();
-    ~Shape();
-    virtual const std::string PrintInfo();
 };
 
+
+/******************************************************************************/
+// Rectangle derived Shape
+
 class Rectangle: public Shape {
-  private:
-    double width, height;
-    std::string info;
-
   public:
-    Rectangle(double w, double h);
+    Rectangle(double w, double h) : Shape(w, h, "Rectangle") {}
-    Rectangle();
+    Rectangle() : Shape(4, 2, "Rectangle") {}
-    ~Rectangle();
+    ~Rectangle() override = default;
-
 };
 
+
+/******************************************************************************/
+// SDL helper functions
+
 int InitScreen(SDL_Window* &window, SDL_Renderer* &renderer);
 
 void DrawDelay(SDL_Renderer* renderer, int delay);