public BBAA Intersect(BBAA o) {
// validate intersection
//if (!Overlaps(o)) return new BBAA(v2f(0, 0), v2f(0, 0));
bool lapX = true, lapY = true;
float ox = 0, dx = 0;
if (o.UL.X >= UL.X && o.LR.X <= LR.X) {
// we're outside
ox = o.UL.X;
dx = o.LR.X - o.UL.X;
} else if (UL.X >= o.UL.X && LR.X <= o.LR.X) {
// we're inside
ox = UL.X;
dx = LR.X - UL.X;
} else if (LR.X > o.UL.X && LR.X < o.LR.X) {
// we're overlapping from the left
ox = o.UL.X;
dx = LR.X - o.UL.X;
} else if (UL.X < o.LR.X && UL.X > o.UL.X) {
// we're overlapping from the right
ox = UL.X;
dx = o.LR.X - UL.X;
} else {
lapX = false;
}
float oy = 0, dy = 0;
if (o.UL.Y >= UL.Y && o.LR.Y <= LR.Y) {
// we're outside
oy = o.UL.Y;
dy = o.LR.Y - o.UL.Y;
} else if (UL.Y >= o.UL.Y && LR.Y <= o.LR.Y) {
// we're inside
oy = UL.Y;
dy = LR.Y - UL.Y;
} else if (LR.Y > o.UL.Y && LR.Y < o.LR.Y) {
// we're overlapping from above
oy = o.UL.Y;
dy = LR.Y - o.UL.Y;
} else if (UL.Y < o.LR.Y && UL.Y > o.UL.Y) {
// we're overlapping from below
oy = UL.Y;
dy = o.LR.Y - UL.Y;
} else {
lapY = false;
}
if (lapX && lapY) return new BBAA(v2f(ox, oy), v2f(ox + dx, oy + dy)).Check();
else return new BBAA(v2f(0, 0), v2f(0, 0));
}
public Player(Assets assets) {
Box = new BBAA(v2f(0, 0), v2f(0.8F, 0.8F));
anim = assets.Animation("cat");
anim.Scale = Box.Size;
}
public BBAA ResolveCollision(BBAA o, out CollidedWith flags) {
flags = 0;
o.Check();
// mutation of a BBAA without explicit copy is acceptable, it's a struct.
// iterate tiles that overlap with "o"
// TODO: Check less tiles. s/2/1/ or s/2/0/ might do.
int ULy = (int)(o.UL.Y - 2).Clamp(0, Height);
int ULx = (int)(o.UL.X - 2).Clamp(0, Width);
int LRy = (int)(o.LR.Y + 2).Clamp(0, Height);
int LRx = (int)(o.LR.X + 2).Clamp(0, Width);
for (int y = ULy; y < LRy; y++) {
for (int x = ULx; x < LRx; x++) {
var tile = this[x, y];
if (tile.Type != null && tile.Type.Collider) {
// TODO: less checks
var intersection = o.Check().Intersect(new BBAA(v2f(x, y), v2f(x + 1, y + 1))).Check();
Vector2f iSize = intersection.Size, oSize = o.Size;
Vector2f iCenter = intersection.Center, oCenter = o.Center;
if (iSize.Len() > 0) {
// only respond to force on the shallow axis
if (iSize.X < iSize.Y) {
if (iCenter.X < oCenter.X) {
flags |= CollidedWith.Left;
o.Position = v2f(intersection.LR.X, o.UL.Y);
} else {
flags |= CollidedWith.Right;
o.Position = v2f(intersection.UL.X - o.Size.X, o.UL.Y);
}
} else {
if (iCenter.Y < oCenter.Y) {
flags |= CollidedWith.Top;
o.Position = v2f(o.UL.X, intersection.LR.Y);
} else {
flags |= CollidedWith.Bottom;
o.Position = v2f(o.UL.X, intersection.UL.Y - o.Size.Y);
}
}
}
}
}
}
return o;
}
public bool Overlaps(BBAA o) {
return Physics.BBAAOverlap(UL.X, UL.Y, LR.X - UL.X, LR.Y - UL.Y,
o.UL.X, o.UL.Y, o.LR.X - o.UL.X, o.LR.Y - o.LR.X);
}
public static void TestIntersect() {
var a = new BBAA(v2f(0, 0), v2f(1, 1));
var b = new BBAA(v2f(0.25F, 0.25F), v2f(0.75F, 0.75F));
AssumeEq(a.Intersect(b), b.Intersect(a));
var c = new BBAA(v2f(0.5F, 0.5F), v2f(1.5F, 1.5F));
AssumeEq(a.Intersect(c), c.Intersect(a));
L.I(a.Intersect(c).Size.ToString());
}