C++ (Cpp) Vec2D::normalize示例

void addVertices(vector<float>& vertices, vector<float>& colors,
                 Vec2D<float> point, Vec2D<float> v1, QColor color,
                 float z = 0.0) {
  Vec2D<float> normal = v1;
  swap(normal.x, normal.y);
  normal.x *= -1;
  normal.normalize();

  Vec2D<float> p1 = point + normal * LINE_WIDTH;
  Vec2D<float> p2 = point - normal * LINE_WIDTH;

  for (int i = 0; i < 2; i++) {
    colors.push_back(color.redF());
    colors.push_back(color.greenF());
    colors.push_back(color.blueF());
    colors.push_back( (color.greenF() + color.redF()) *0.3f  );
  }

  vertices.push_back(p1.x);
  vertices.push_back(p1.y);
  vertices.push_back(z);

  vertices.push_back(p2.x);
  vertices.push_back(p2.y);
  vertices.push_back(z);
}