Thread: Nothing is being rendered using openGL but glClear() wors perfectly!

Hi! I am developing a simple convex hull algorithm and visual representation of the solution. I want to render it using glfw3 and OpenGL. However, the window is created and everything it clears everything with the exact color I need but it will not render anything... Not even a simple quad.

main.cpp

Code:

int main(){


    const char *title = "testing";
    GLFWwindow* window = initWindow(640, 480,title);
    while(!glfwWindowShouldClose(window)){


        glClearColor(0.658824, 0.658824, 0.658824, 0.658824);
        glClear(GL_COLOR_BUFFER_BIT);
        glOrtho(0, 680, 0, 480, 0, 680);


        glColor3f(1.0,0.0,0.0);
        glBegin(GL_TRIANGLES);
            drawPoint(300, 300, 10);
        glEnd();


        glFlush();
        glfwSwapBuffers(window);
        glfwPollEvents();
    }


    return 0;
}

initWindow

Code:

GLFWwindow* initWindow(int screen_width, int screen_height, const char* title){
    GLFWwindow* window;
    glfwSetErrorCallback(error_callback);


    if(!glfwInit())
        exit(EXIT_FAILURE);


    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);


    window = glfwCreateWindow(screen_width, screen_height, title, NULL, NULL);


    glfwSetKeyCallback(window, key_callback);


    glfwMakeContextCurrent(window);


    glfwSwapInterval(1);


    return window;
}

drawPoint

Code:

void drawPoint(int a_x, int a_y, int size=DEFAULT_POINT_SIZE){


    //set the position of the point
    int x = a_x - (int)size/2;
    int y = a_y - (int)size/2;


    //draw first triangle
    glVertex2f(x,y);
    glVertex2f(x,y+size+1);
    glVertex2f(x+size+1,y);


    //draw second triangle
    glVertex2f(x,y+size+1);
    glVertex2f(x+size+1, y+size+1);
    glVertex2f(x+size+1,y);


}

Any ideas? Thanks in advance!

EDIT: I probably should mention that I a using a Linux machine