This has been asked for here and on irc. The tutorial claims a line with no thickness is simply two sf::Vertex, whereas a line with thickness is a rotated rectangle.
However, there's a difference: if the user has two points and he wants a line segment between them with thickness, then boilerplate code needs to be written for said rectangle to achieve desired effect.
A simple class for line segments could look like this:
class sfLine : public sf::Drawable
{
public:
sfLine(const sf::Vector2f& point1, const sf::Vector2f& point2):
color(sf::Color::Yellow), thickness(5.f)
{
sf::Vector2f direction = point2 - point1;
sf::Vector2f unitDirection = direction/std::sqrt(direction.x*direction.x+direction.y*direction.y);
sf::Vector2f unitPerpendicular(-unitDirection.y,unitDirection.x);
float halfThick = thickness/2;
vertices[0].position = point1 + halfThick*unitPerpendicular;
vertices[1].position = point2 + halfThick*unitPerpendicular;
vertices[2].position = point2 - halfThick*unitPerpendicular;
vertices[3].position = point1 - halfThick*unitPerpendicular;
for (auto& vertex : vertices)
vertex.color = color;
}
void draw(sf::RenderTarget &target, sf::RenderStates states) const
{
target.draw(vertices.data(),4,sf::Quads);
}
private:
std::array<sf::Vertex,4> vertices;
float thickness;
sf::Color color;
};
The c++11 keywords can be done away with, setters for color and thickness added, assert that the points are distinct.
Note how Thor library offers a line shape and given point1 and point2 a segment could be obtained this way:
auto myLine = thor::Shapes::line(point2-point1,sf::Color::Yellow, 3.f);
myLine.setPosition(point1);
But I do think this results in a 'heavier' myLine than the class presented above.
