Animation

...

glRotatef(anglePyramid, 1.0f, 1.0f, 0.0f); // Rotate about the (1,1,0)-axis [NEW]

glBegin(GL_TRIANGLES); // Begin drawing the pyramid with 4 triangles

// Front

glColor3f(1.0f, 0.0f, 0.0f); // Red

glVertex3f( 0.0f, 1.0f, 0.0f);

glColor3f(0.0f, 1.0f, 0.0f); // Green

glVertex3f(-1.0f, -1.0f, 1.0f);

glColor3f(0.0f, 0.0f, 1.0f); // Blue

glVertex3f(1.0f, -1.0f, 1.0f);

// Right

glColor3f(1.0f, 0.0f, 0.0f); // Red

glVertex3f(0.0f, 1.0f, 0.0f);

glColor3f(0.0f, 0.0f, 1.0f); // Blue

glVertex3f(1.0f, -1.0f, 1.0f);

glColor3f(0.0f, 1.0f, 0.0f); // Green

glVertex3f(1.0f, -1.0f, -1.0f);

// Back

glColor3f(1.0f, 0.0f, 0.0f); // Red

glVertex3f(0.0f, 1.0f, 0.0f);

glColor3f(0.0f, 1.0f, 0.0f); // Green

glVertex3f(1.0f, -1.0f, -1.0f);

glColor3f(0.0f, 0.0f, 1.0f); // Blue

glVertex3f(-1.0f, -1.0f, -1.0f);

// Left

glColor3f(1.0f,0.0f,0.0f); // Red

glVertex3f( 0.0f, 1.0f, 0.0f);

glColor3f(0.0f,0.0f,1.0f); // Blue

glVertex3f(-1.0f,-1.0f,-1.0f);

glColor3f(0.0f,1.0f,0.0f); // Green

glVertex3f(-1.0f,-1.0f, 1.0f);

glEnd(); // Done drawing the pyramid

glutSwapBuffers(); // Swap the front and back frame buffers (double buffering)

// Update the rotational angle after each refresh [NEW]

anglePyramid += 0.2f;

angleCube -= 0.15f;

}

/* Called back when timer expired [NEW] */

void timer(int value) {

glutPostRedisplay(); // Post re-paint request to activate display()

glutTimerFunc(refreshMills, timer, 0); // next timer call milliseconds later

}

/* Handler for window re-size event. Called back when the window first appears and

whenever the window is re-sized with its new width and height */

void reshape(GLsizei width, GLsizei height) { // GLsizei for non-negative integer

// Compute aspect ratio of the new window

if (height == 0) height = 1; // To prevent divide by 0

GLfloat aspect = (GLfloat)width / (GLfloat)height;

// Set the viewport to cover the new window

glViewport(0, 0, width, height);

// Set the aspect ratio of the clipping volume to match the viewport

glMatrixMode(GL_PROJECTION); // To operate on the Projection matrix

glLoadIdentity(); // Reset

// Enable perspective projection with fovy, aspect, zNear and zFar

gluPerspective(45.0f, aspect, 0.1f, 100.0f);

}

/* Main function: GLUT runs as a console application starting at main() */

int main(int argc, char** argv) {

glutInit(&argc, argv); // Initialize GLUT

glutInitDisplayMode(GLUT_DOUBLE); // Enable double buffered mode

glutInitWindowSize(640, 480); // Set the window’s initial width & height

glutInitWindowPosition(50, 50); // Position the window’s initial top-left corner

glutCreateWindow(title); // Create window with the given title

glutDisplayFunc(display); // Register callback handler for window re-paint event

glutReshapeFunc(reshape); // Register callback handler for window re-size event

initGL(); // Our own OpenGL initialization

glutTimerFunc(0, timer, 0); // First timer call immediately [NEW]

glutMainLoop(); // Enter the infinite event-processing loop

return 0;

}