Tortuga

Simple C file to introduce new students to programming. It emulates the Logo language turte.

I did it for my lectures at Universitat Politècnica de Catalunya, so the name of the constants and functions are in spanish language.

It works with any C compiler, and requires Simple Directmedia Layer (SDL) v1.2 to work.

Building instructions for Ubuntu

1. Install GCC and SDL, if not already installed: sudo apt-get install build-essential libsdl1.2-dev
2. Compile the example file in the same folder as tortuga.h with -lSDL and -lm options: gcc example.c -o example -lSDL -lm
3. Run the binary: ./example

And, voilà! Your turtle is drawing your screen:

Functions and constants reference

• void inicializar()
  • Starts the Tortuga environment.
• void finalizar()
  • Finishes the Tortuga environment.
• void girar(float grados)
  • Rotates the turtle.
  • Parameters:
    • float grados: the number of degrees to rotate the turtle. If grados is positive, turtle will rotate to its left. Otherwise, it will rotate to its right.
• void avanzar(float distancia)
  • Makes turtle to go ahead.
  • Parameters
    • float distancia: number of steps to advance.
• void posicion_inicial(float posX, float posY)
  • Sets the position of the turtle in the screen.
  • Parameters
    • float posX: the X position of the turtle.
    • float posY: the Y position of the turtle.
• void angulo_inicial(float grados)
  • Sets the angle of the turtle.
  • Parameters
    • float grados: the new angle of the turtle, in degrees.
• void punta_lapiz(int color, int grosor)
  • Sets the properties of the pencil.
  • Parameters
    • int color: the color of the pencil. It can be one of the next constants: BLACK, WHITE, RED, BLUE, GREEN, WHITE
    • int grosor: the widht of the pencil.
• void estado_lapiz(int estado)
  • Sets the status of the pencil.
  • Parameters
    • int estado: the status of the pencil. It can be one of the next constants: PEN_DOWN (the turtle draws while it walks), PEN_UP (the turtle does not draw when it walks).
• void velocidad_tortuga(int velocidad)
  • Sets the speed of the turtle.
  • Parameters
    • int velocidad: the speed of the turtle. It can be one of the next constants, ordered from slowest to fastest: VELOCIDAD_LENTA, VELOCIDAD_MEDIA, VELOCIDAD_RAPIDA, VELOCIDAD_MAXIMA
• void puntero_lapiz(int visible)
  • Sets the visibility of the turtle.
  • Parameters
    • int visible: it can be one of the next constants: ON turns the turtle visible, OFF turns the turtle invisible

Si te gustan mis aportaciones a github, quizás te gustará mi libro Del bit a la Nube