SDL3-DiamondSquare

What is this?

This is a C++ project that uses the Diamond-Square Algorithm to create cool-looking terrain. It then shows the terrain in 2D (like a grayscale map) and in 3D (like a mini mountain range). It uses SDL3 to draw everything on the screen. You can even move the camera around to see the terrain from different angles.

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Features

1. Diamond-Square Algorithm:

   • Makes a heightmap (basically a grid of numbers that represent how high or low the terrain is).
   • You can change how big the map is and how bumpy the terrain looks.

2. 2D Heightmap:

   • Shows the heightmap as a grayscale grid. Darker = lower, lighter = higher.

3. 3D Terrain:

   • Turns the heightmap into a 3D view so it looks like mountains and valleys.
   • You can zoom in/out and rotate the camera to explore.

4. Controls:

   • W, A, S, D: Rotate the camera.
   • I, O: Zoom in and out.

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What You Need

• C++ Compiler: Like GCC or Clang. Make sure it supports C++17.
• SDL3: This is the library used to draw stuff on the screen. You can download it from here.
• A terminal or command prompt to run the program.

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How to Run

1. Install SDL3:

   • Download SDL3 from the official website and install it. Make sure your compiler can find the SDL3 files.

2. Clone the Repository:

   • Copy the code from the src/main.cc file or paste into a terminal:

     git clone https://github.com/zerootoad/SDL3-DiamondSquare.git
     cd SDL3-DiamondSquare

3. Compile the Code:

   • Navigate to the folder where the code is.
   • Run this command to compile:

     g++ -std=c++17 -o terrain src/main.cc -lSDL3

   • If it doesn’t work, make sure SDL3 is installed correctly.

4. Run the Program:

   • After compiling, run the program:

     ./terrain

   • Two windows will pop up (overlapped): one for the 2D heightmap and one for the 3D terrain.

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How to Use

• When the program runs, you’ll see:

  • A 2D heightmap (looks like a grid of gray squares).
  • A 3D terrain (looks like mountains or valleys).

• Use these keys to control the 3D view:

  • W, A, S, D: Rotate the camera.
  • I, O: Zoom in and out.

• Close either window to quit the program.

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How It Works

• DiamondSquare Class:

  • This is where the terrain is generated. It uses the Diamond-Square Algorithm to make the heightmap.
  • Check out: https://web.archive.org/web/20170812230846/http://www.gameprogrammer.com/fractal.html

• DiamondSquareSDL Class:

  • This handles all the drawing and camera controls using SDL.

• Main Function:

  • This is where everything starts. It creates the terrain, sets up the windows, and runs the program loop.

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Customization

• Change Terrain Size:

  • In the main() function, change the 65 in DiamondSquare ds(65, 1); to a different number. It has to be an odd number (like 33, 65, 129, etc.).

• Change Terrain Roughness:

  • Change the 1 in DiamondSquare ds(65, 1); to a bigger number for more bumpy terrain or a smaller number for smoother terrain.

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Example Code

Here’s the main part of the code:

int main() {
  DiamondSquare ds(65, 1); // 65x65 grid, roughness = 1
  ds.generate(); // Make the terrain

  DiamondSquareSDL sdl;
  if (!sdl.init()) { // Set up SDL
    return 1;
  }

  bool running = true;
  while (running) {
    SDL_Event event;
    while (SDL_PollEvent(&event)) {
      if (event.type == SDL_EVENT_QUIT) {
        running = false; // Quit if the window is closed
      }
    }

    sdl.handle_input(); // Check for key presses
    sdl.render_height_map(ds); // Draw the 2D heightmap
    sdl.render_terrain(ds); // Draw the 3D terrain

    SDL_Delay(16); // Wait a bit to make it run
  }

  sdl.cleanup(); // Clean up the windows
  return 0;
}

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Why I Made This

I made this project because I thought procedural terrain generation was pretty dope and also to learn how graphics and rendering work.

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Feedback

If you have any suggestions or find any bugs, let me know.