ComputerGraphicsGo-

Hail Computer Graphics!

This is a repository for my CG course, and it serves as my git practice as well.

---

Lab 1: Draw a national flag!

• Drawing stars:

  void Rotate(double angle, double* X, double* Y) {
  	double lastX = *X, lastY = *Y;
  	*X = lastX * cos(angle) - lastY * sin(angle);
  	*Y = lastX * sin(angle) + lastY * cos(angle);
  }
  ...
  for (int i = 0; i < 5; i++) {
  		glVertex2f((Xvex + S.Xcenter) * Xgrid, (Yvex + S.Ycenter) * Ygrid);
  		glVertex2f((Xcave + S.Xcenter) * Xgrid, (Ycave + S.Ycenter) * Ygrid);
  		Rotate(angle, &Xvex, &Yvex);
  		glVertex2f((Xvex + S.Xcenter) * Xgrid, (Yvex + S.Ycenter) * Ygrid);
  		glVertex2f((Xcave + S.Xcenter) * Xgrid, (Ycave + S.Ycenter) * Ygrid);
  		Rotate(angle, &Xcave, &Ycave);
  	}

  The function Rotate uses the rotation matrix.

  Glut Drawing mode: GL_TRIANGLE_FAN.

  Stars are defined as a struct:

  typedef struct{
  	int Xcenter;
  	int Ycenter;
  	double radius;
  	double angle;
  }STAR;

  to ensure better reusability.