public ICollection <Vector2> ComputePositionsOnPlane(IEnumerable <Vector3D> positions)
{
if (positions == null)
{
throw new ArgumentNullException("positions");
}
IList <Vector2> positionsOnPlane = new List <Vector2>(CollectionAlgorithms.EnumerableCount(positions));
foreach (Vector3 position in positions)
{
Vector3 intersectionPoint;
if (IntersectionTests.TryRayPlane(Vector3.Zero, position.Normalize(), _normal, _d, out intersectionPoint))
{
Vector3D v = intersectionPoint - _origin;
positionsOnPlane.Add(new Vector2D(_xAxis.Dot(v), _yAxis.Dot(v)));
}
else
{
// Ray does not intersect plane
}
}
return(positionsOnPlane);
}
/// <summary>
/// Realiza los tests de colisión
/// </summary>
/// <param name="obj1">Objeto 1</param>
/// <param name="obj2">Objeto 2</param>
public static void TestCollision(IPhysicObject obj1, IPhysicObject obj2)
{
if ((obj1 != null) && (obj2 != null))
{
//if (obj1.BSph.Intersects(obj2.BSph))
{
if (IntersectionTests.BoxAndBox(obj1.TransformedOBB, obj2.TransformedOBB))
{
obj1.Reaction(obj2);
obj2.Reaction(obj1);
}
}
}
}
public void SphereAndTriTest()
{
bool intersect = false;
CollisionSphere sphere = new CollisionSphere(1f, 1f);
Triangle triangleHAU = new Triangle(new Vector3(0, 1, 10), new Vector3(-10, 1, -10), new Vector3(10, 1, -10));
Triangle triangleHBU = new Triangle(new Vector3(0, 0, 10), new Vector3(-10, 0, -10), new Vector3(10, 0, -10));
Triangle triangleHCU = new Triangle(new Vector3(0, -1, 10), new Vector3(-10, -1, -10), new Vector3(10, -1, -10));
Triangle triangleHAD = new Triangle(new Vector3(0, 1, 10), new Vector3(10, 1, -10), new Vector3(-10, 1, -10));
Triangle triangleHBD = new Triangle(new Vector3(0, 0, 10), new Vector3(10, 0, -10), new Vector3(-10, 0, -10));
Triangle triangleHCD = new Triangle(new Vector3(0, -1, 10), new Vector3(10, -1, -10), new Vector3(-10, -1, -10));
sphere.SetPosition(new Vector3(0, 2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAU);
Assert.AreEqual(true, intersect, "Error en Triángulo sobre 0 normal UP, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, 0, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAU);
Assert.AreEqual(true, intersect, "Error en Triángulo sobre 0 normal UP, contacto perfecto bajo plano");
sphere.SetPosition(new Vector3(0, 1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAU);
Assert.AreEqual(true, intersect, "Error en Triángulo sobre 0 normal UP, contacto en mitad de la esfera");
sphere.SetPosition(new Vector3(0, 3, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAU);
Assert.AreEqual(false, intersect, "Error en Triángulo sobre 0 normal UP, sin contacto sobre el plano");
sphere.SetPosition(new Vector3(0, -1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAU);
Assert.AreEqual(false, intersect, "Error en Triángulo sobre 0 normal UP, sin contacto bajo el plano");
sphere.SetPosition(new Vector3(0, 2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAD);
Assert.AreEqual(true, intersect, "Error en Triángulo sobre 0 normal DOWN, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, 0, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAD);
Assert.AreEqual(true, intersect, "Error en Triángulo sobre 0 normal DOWN, contacto perfecto bajo plano");
sphere.SetPosition(new Vector3(0, 1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAD);
Assert.AreEqual(true, intersect, "Error en Triángulo sobre 0 normal DOWN, contacto en mitad de la esfera");
sphere.SetPosition(new Vector3(0, 3, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAD);
Assert.AreEqual(false, intersect, "Error en Triángulo sobre 0 normal DOWN, sin contacto sobre el plano");
sphere.SetPosition(new Vector3(0, -1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHAD);
Assert.AreEqual(false, intersect, "Error en Triángulo sobre 0 normal DOWN, sin contacto bajo el plano");
sphere.SetPosition(new Vector3(0, 1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(true, intersect, "Error en Triángulo en 0 normal UP, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, -1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(true, intersect, "Error en Triángulo en 0 normal UP, contacto perfecto bajo plano");
sphere.SetPosition(new Vector3(0, 0, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(true, intersect, "Error en Triángulo en 0 normal UP, contacto en mitad de la esfera");
sphere.SetPosition(new Vector3(0, 2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(false, intersect, "Error en Triángulo en 0 normal UP, sin contacto sobre el plano");
sphere.SetPosition(new Vector3(0, -2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(false, intersect, "Error en Triángulo en 0 normal UP, sin contacto bajo el plano");
sphere.SetPosition(new Vector3(0, 1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBD);
Assert.AreEqual(true, intersect, "Error en Triángulo en 0 normal DOWN, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, -1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBD);
Assert.AreEqual(true, intersect, "Error en Triángulo en 0 normal DOWN, contacto perfecto bajo plano");
sphere.SetPosition(new Vector3(0, 0, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBD);
Assert.AreEqual(true, intersect, "Error en Triángulo en 0 normal DOWN, contacto en mitad de la esfera");
sphere.SetPosition(new Vector3(0, 2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBD);
Assert.AreEqual(false, intersect, "Error en Triángulo en 0 normal DOWN, sin contacto sobre el plano");
sphere.SetPosition(new Vector3(0, -2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBD);
Assert.AreEqual(false, intersect, "Error en Triángulo en 0 normal DOWN, sin contacto bajo el plano");
sphere.SetPosition(new Vector3(0, 0, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCU);
Assert.AreEqual(true, intersect, "Error en Triángulo en -1 normal UP, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, -2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCU);
Assert.AreEqual(true, intersect, "Error en Triángulo en -1 normal UP, contacto perfecto bajo plano");
sphere.SetPosition(new Vector3(0, -1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCU);
Assert.AreEqual(true, intersect, "Error en Triángulo en -1 normal UP, contacto en mitad de la esfera");
sphere.SetPosition(new Vector3(0, 1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCU);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal UP, sin contacto sobre el plano");
sphere.SetPosition(new Vector3(0, -3, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCU);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal UP, sin contacto bajo el plano");
sphere.SetPosition(new Vector3(0, 0, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCD);
Assert.AreEqual(true, intersect, "Error en Triángulo en -1 normal DOWN, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, -2, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCD);
Assert.AreEqual(true, intersect, "Error en Triángulo en -1 normal DOWN, contacto perfecto bajo plano");
sphere.SetPosition(new Vector3(0, -1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCD);
Assert.AreEqual(true, intersect, "Error en Triángulo en -1 normal DOWN, contacto en mitad de la esfera");
sphere.SetPosition(new Vector3(0, 1, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCD);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal DOWN, sin contacto sobre el plano");
sphere.SetPosition(new Vector3(0, -3, 0));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHCD);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal DOWN, sin contacto bajo el plano");
sphere.SetPosition(new Vector3(-9, 0, 9));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal DOWN, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(9, 0, 9));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal DOWN, contacto perfecto sobre plano");
sphere.SetPosition(new Vector3(0, 0, -12));
intersect = IntersectionTests.SphereAndTri(sphere, triangleHBU);
Assert.AreEqual(false, intersect, "Error en Triángulo en -1 normal DOWN, contacto perfecto sobre plano");
}
// Since these physics are independent from Unity's doing physics in Update
// as opposed to FixedUpdate is not a problem.
void Update()
{
Vector3[] vertices = terrainMesh.vertices;
foreach (Metaball ball in metaballs)
{
// Check if ball is instantiated.
if (!ball.instantiated)
{
// If ball is not instantiated, check if it should be.
if (framesSinceInstantiation > waterSpawnInterval)
{
// Ball should be instantiated, reset framesSinceInstantiation.
framesSinceInstantiation = 0;
ball.instantiated = true;
numInstantiatedBalls++;
}
else
{
// Ball should not be instantiated, skip all physics.
continue;
}
}
// Check if ball is within bounds.
if (ball.transform.position.y < terrainBounds.min.y)
{
// Set new spawn position and reset velocity if ball is out of bounds.
ball.transform.position = GetRandomSpawnPoint();
ball.velocity = Vector3.Lerp(Vector3.zero, waterInitialMaxVelocity, UnityEngine.Random.Range(0.0f, 1.0f));
}
// Calculate the cumulative acceleration.
Vector3 totalAcceleration = gravityAcceleration * Vector3.down;
foreach (Metaball otherBall in metaballs)
{
if (ball == otherBall || !otherBall.instantiated)
{
continue;
}
// Force is like a spring force between each metaball and each other metaball.
// The spring force is to keep balls at a minimum distance from eachother.
// The force weakens the further away the balls are from eachother beyond the
// minimum distance.
Vector3 ballToOther = ball.transform.position - otherBall.transform.position;
Vector3 springForce = ballSpringStiffness * (-ballToOther + Vector3.Normalize(ballToOther) * minimumDistance);
// Force equation gives F = m * a, and with m = 1 for simplicity, we have F = a.
// Scale by 0.5 because this is only one of the two balls.
// If ball is outside maximumDistance of the equilibrium point, apply no force.
if (ballToOther.magnitude - minimumDistance < maximumDistance)
{
totalAcceleration += 0.5f * springForce;
}
}
// Update velocity according to acceleration.
ball.velocity += totalAcceleration * Time.deltaTime;
// Update position according to velocity.
ball.lastPosition = ball.transform.position;
ball.transform.position += ball.velocity * Time.deltaTime;
// Check for intersection.
int[] triangles;
if (IntersectionTests.GetTriangles(ball.transform.position, rootNode, out triangles))
{
// Iterate through all found triangles.
for (int i = 0; i < triangles.Length; i += 3)
{
// Get triangle vertices.
Vector3[] triangle = new Vector3[] {
vertices[triangles[i]],
vertices[triangles[i + 1]],
vertices[triangles[i + 2]]
};
// Test for intersection.
Vector3 rayDirection = ball.transform.position - ball.lastPosition;
float distance = rayDirection.magnitude;
rayDirection = Vector3.Normalize(rayDirection);
Vector3?intersectionPoint;
// If intersection, compute new position and velocity.
if (IntersectionTests.RayTriangleTest(ball.lastPosition, rayDirection, distance, triangle, out intersectionPoint))
{
Vector3 point = (Vector3)intersectionPoint;
Vector3 normal = Vector3.Normalize(
Vector3.Cross(triangle[2] - triangle[0], triangle[1] - triangle[0]));
// Get reflection direction.
Vector3 newDirection = Vector3.Normalize(2 * Vector3.Dot(-rayDirection, normal) * normal + rayDirection);
// Set dampened velocity.
ball.velocity = (1.0f - groundDamping) * ball.velocity.magnitude * newDirection;
// Update last position to the intersection point.
ball.lastPosition = point + constantOffset * Vector3.up;
// The new ball position is the distance traveled from the intersection point
// the distance traveled beyond the triangle, but adjusted for the new
// velocity and along the reflection direction.
ball.transform.position = point + constantOffset * Vector3.up + ball.velocity * Time.deltaTime;
// Break out of loop checking triangles after intersection was found.
break;
}
}
}
}
framesSinceInstantiation++;
}
