OrientedBoundingBox (const sf::Sprite& Object) // Calculate the four points of the OBB from a transformed (scaled, rotated...) sprite
{
sf::Transform trans = Object.getTransform();
sf::IntRect local = Object.getTextureRect();
Points[0] = trans.transformPoint(0.f, 0.f);
Points[1] = trans.transformPoint(local.width, 0.f);
Points[2] = trans.transformPoint(local.width, local.height);
Points[3] = trans.transformPoint(0.f, local.height);
}
sf::IntRect Collision::GetAABB(const sf::Sprite& Object) {
//Get the top left corner of the sprite regardless of the sprite's center
//This is in Global Coordinates so we can put the rectangle back into the right place
sf::Transform objectGlobalTransform = Object.getTransform();
sf::Vector2f pos = objectGlobalTransform.transformPoint(sf::Vector2f(0, 0));
//Store the size so we can calculate the other corners
sf::Vector2f size = getSize(Object);
float Angle = Object.getRotation();
//Bail out early if the sprite isn't rotated
if (Angle == 0.0f) {
return sf::IntRect(static_cast<int> (pos.x),
static_cast<int> (pos.y),
static_cast<int> (pos.x + size.x),
static_cast<int> (pos.y + size.y));
}
//Calculate the other points as vectors from (0,0)
//Imagine sf::Vector2f A(0,0); but its not necessary
//as rotation is around this point.
sf::Vector2f B(size.x, 0);
sf::Vector2f C(size.x, size.y);
sf::Vector2f D(0, size.y);
//Rotate the points to match the sprite rotation
B = RotatePoint(B, Angle);
C = RotatePoint(C, Angle);
D = RotatePoint(D, Angle);
//Round off to int and set the four corners of our Rect
int Left = static_cast<int> (MinValue(0.0f, B.x, C.x, D.x));
int Top = static_cast<int> (MinValue(0.0f, B.y, C.y, D.y));
int Right = static_cast<int> (MaxValue(0.0f, B.x, C.x, D.x));
int Bottom = static_cast<int> (MaxValue(0.0f, B.y, C.y, D.y));
Left += pos.x;
Top += pos.y;
//Create a Rect from out points and move it back to the correct position on the screen
sf::IntRect AABB = sf::IntRect(Left, Top, size.x, size.y);
//AABB.Offset(static_cast<int> (pos.x), static_cast<int> (pos.y));
return AABB;
}
void TEALShow::OrientedBox( sf::Sprite &s, sf::Color col)
{
AddTransformedRectanglePoints( s.getLocalBounds(), s.getTransform(), col );
}
