Bala::Bala(float _v, sf::Sprite& _cannon, sf::Image& imagen)
{
float cannonA, cannonX, cannonY, cannonH;
//Cargo sprite
sprite.SetImage(imagen);
sprite.SetCenter(imagen.GetWidth()/2, imagen.GetHeight()/2);
//Inicializo variables
dt = 0.0f;
cannonA = _cannon.GetRotation();
cannonX = _cannon.GetPosition().x;
cannonY = _cannon.GetPosition().y;
//Tomo el tamaño sobre el eje x como el largo del cañon
//porque sin rotar la misma se encuentra en horizontal
cannonH = _cannon.GetSize().x;
//Descompongo la velocidad inicial
vx = _v * (cos(cannonA/180*PI));
vy = _v * (sin(cannonA/180*PI));
//Posicion inicial bala según la posición del cañon
//usando trigonometria
xi = cannonX + ((cos(cannonA/180*PI) * cannonH));
yi = cannonY - ((sin(cannonA/180*PI) * cannonH));
sprite.SetPosition(xi, yi);
}
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::Vector2f pos = Object.TransformToGlobal(sf::Vector2f(0, 0));
//Store the size so we can calculate the other corners
sf::Vector2f size = Object.GetSize();
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));
//Create a Rect from out points and move it back to the correct position on the screen
sf::IntRect AABB = sf::IntRect(Left, Top, Right, Bottom);
AABB.Offset(static_cast<int> (pos.x), static_cast<int> (pos.y));
return AABB;
}
bool Collision::BoundingBoxTest(const sf::Sprite& Object1, const sf::Sprite& Object2) {
sf::Vector2f A, B, C, BL, TR;
sf::Vector2f HalfSize1 = Object1.GetSize();
sf::Vector2f HalfSize2 = Object2.GetSize();
//For somereason the Vector2d divide by operator
//was misbehaving
//Doing it manually
HalfSize1.x /= 2;
HalfSize1.y /= 2;
HalfSize2.x /= 2;
HalfSize2.y /= 2;
//Get the Angle we're working on
float Angle = Object1.GetRotation() - Object2.GetRotation();
float CosA = cos(Angle * RADIANS_PER_DEGREE);
float SinA = sin(Angle * RADIANS_PER_DEGREE);
float t, x, a, dx, ext1, ext2;
//Normalise the Center of Object2 so its axis aligned an represented in
//relation to Object 1
C = Object2.GetPosition();
C -= Object1.GetPosition();
C = RotatePoint(C, Object2.GetRotation());
//Get the Corners
BL = TR = C;
BL -= HalfSize2;
TR += HalfSize2;
//Calculate the vertices of the rotate Rect
A.x = -HalfSize1.y*SinA;
B.x = A.x;
t = HalfSize1.x*CosA;
A.x += t;
B.x -= t;
A.y = HalfSize1.y*CosA;
B.y = A.y;
t = HalfSize1.x*SinA;
A.y += t;
B.y -= t;
t = SinA * CosA;
// verify that A is vertical min/max, B is horizontal min/max
if (t < 0) {
t = A.x;
A.x = B.x;
B.x = t;
t = A.y;
A.y = B.y;
B.y = t;
}
// verify that B is horizontal minimum (leftest-vertex)
if (SinA < 0) {
B.x = -B.x;
B.y = -B.y;
}
// if rr2(ma) isn't in the horizontal range of
// colliding with rr1(r), collision is impossible
if (B.x > TR.x || B.x > -BL.x) return false;
// if rr1(r) is axis-aligned, vertical min/max are easy to get
if (t == 0) {
ext1 = A.y;
ext2 = -ext1;
}// else, find vertical min/max in the range [BL.x, TR.x]
else {
x = BL.x - A.x;
a = TR.x - A.x;
ext1 = A.y;
// if the first vertical min/max isn't in (BL.x, TR.x), then
// find the vertical min/max on BL.x or on TR.x
if (a * x > 0) {
dx = A.x;
if (x < 0) {
dx -= B.x;
ext1 -= B.y;
x = a;
} else {
dx += B.x;
ext1 += B.y;
}
ext1 *= x;
ext1 /= dx;
ext1 += A.y;
}
x = BL.x + A.x;
a = TR.x + A.x;
ext2 = -A.y;
// if the second vertical min/max isn't in (BL.x, TR.x), then
// find the local vertical min/max on BL.x or on TR.x
if (a * x > 0) {
dx = -A.x;
if (x < 0) {
dx -= B.x;
ext2 -= B.y;
x = a;
} else {
dx += B.x;
ext2 += B.y;
}
ext2 *= x;
ext2 /= dx;
ext2 -= A.y;
}
}
// check whether rr2(ma) is in the vertical range of colliding with rr1(r)
// (for the horizontal range of rr2)
return !((ext1 < BL.y && ext2 < BL.y) ||
(ext1 > TR.y && ext2 > TR.y));
}