public void TestCloseMiss()
{
Vector2 boxExtents = new Vector2(10.0f, 10.0f);
LineContacts contacts = Line2Aabb2Collider.FindContacts(
new Vector2(0.0f, 10.1f), Vector2.UnitX, boxExtents
);
Assert.IsNaN(contacts.EntryTime);
Assert.IsNaN(contacts.ExitTime);
}
public void TestContact()
{
Vector2 boxExtents = new Vector2(10.0f, 10.0f);
LineContacts contacts = Line2Aabb2Collider.FindContacts(
new Vector2(-2.5f, -2.5f), Vector2.UnitY, boxExtents
);
Assert.That(
contacts.EntryTime,
Is.EqualTo(-7.5f).Within(Specifications.MaximumDeviation).Ulps
);
Assert.That(
contacts.ExitTime,
Is.EqualTo(12.5f).Within(Specifications.MaximumDeviation).Ulps
);
}
public void TestContactOnCornerDefinedBox()
{
LineContacts contacts = Line2Aabb2Collider.FindContacts(
new Vector2(97.5f, -102.5f), Vector2.UnitY,
new Vector2(90.0f, -110.0f), new Vector2(110.0f, -90.0f)
);
Assert.That(
contacts.EntryTime,
Is.EqualTo(-7.5f).Within(Specifications.MaximumDeviation).Ulps
);
Assert.That(
contacts.ExitTime,
Is.EqualTo(12.5f).Within(Specifications.MaximumDeviation).Ulps
);
}
public void TestDiagonalCloseMiss()
{
Vector2 boxExtents = new Vector2(5.0f, 5.0f);
Vector2 diagonalVector = Vector2.Normalize(Vector2.One);
LineContacts contacts = Line2Aabb2Collider.FindContacts(
new Vector2(-10.1f, 0.0f), diagonalVector, boxExtents
);
Assert.IsNaN(contacts.EntryTime);
Assert.IsNaN(contacts.ExitTime);
diagonalVector.Y = -diagonalVector.Y;
contacts = Line2Aabb2Collider.FindContacts(
new Vector2(0.0f, 10.1f), diagonalVector, boxExtents
);
Assert.IsNaN(contacts.EntryTime);
Assert.IsNaN(contacts.ExitTime);
}
/// <summary>Determines where a ray will hit a box, if at all</summary>
/// <param name="rayStart">Starting point of the ray</param>
/// <param name="rayDirection">Direction into which the ray extends</param>
/// <param name="boxExtents">Extents of the box</param>
/// <returns>The intersection points between the ray and the box, if any</returns>
public static LineContacts FindContacts(
Vector2 rayStart, Vector2 rayDirection, Vector2 boxExtents
)
{
LineContacts contacts = Line2Aabb2Collider.FindContacts(
rayStart, rayDirection, boxExtents
);
// If the line has entered the box before the reference point, this means
// that the ray starts within the box, thus, its first contact occurs immediately
if (!float.IsNaN(contacts.EntryTime))
{
if (contacts.ExitTime < 0.0f) // Entry & exit before the ray's beginning?
{
return(LineContacts.None);
}
else if (contacts.EntryTime < 0.0f) // Only entry before ray's beginning?
{
contacts.EntryTime = 0.0f;
}
}
return(contacts);
}
