public Fix RayCastCallback(FixVec2 pointA, FixVec2 pointB, Fix maxFraction, int proxyID, out TFRaycastHit2D hit, TFLayerMask mask)
{
TFRigidbody rigid = bodies[dynamicTree.nodes[proxyID].bodyIndex];
if (!(mask == (mask | (1 << rigid.layer))))
{
// This object is not in the mask, ignore it.
hit = new TFRaycastHit2D();
return(maxFraction);
}
rigid.coll.Raycast(out hit, pointA, pointB, maxFraction);
if (!hit)
{
// We did not hit the body, ignore it and use our max ray length.
return(maxFraction);
}
Fix fraction = hit.fraction;
FixVec2 point = (Fix.one - fraction) * pointA + fraction * pointB;
hit.point = point;
hit.distance = (point - pointA).GetMagnitude();
return(RayCastCallback(rigid, hit.point, hit.normal, hit.fraction));
}
public override bool Raycast(out TFRaycastHit2D hit, FixVec2 pointA, FixVec2 pointB, Fix maxFraction)
{
hit = default;
FixVec2 center = (FixVec2)tdTransform.Position;
FixVec2 s = pointA - center;
Fix b = FixVec2.Dot(s, s) - radius * radius;
// Solve quadratic equation.
FixVec2 r = pointB - pointA;
Fix c = FixVec2.Dot(s, r);
Fix rr = FixVec2.Dot(r, r);
Fix sigma = c * c - rr * b;
// Check for negative discriminant and short segment.
if (sigma < Fix.zero || rr < Fix.Epsilon)
{
return(false);
}
// Find the point of intersection on the line with the circle.
Fix a = -(c + FixMath.Sqrt(sigma));
// Is the intersection point on the segment?
if (Fix.zero <= a && a <= maxFraction * rr)
{
a /= rr;
hit.fraction = a;
hit.normal = s + a * r;
hit.normal.Normalize();
return(true);
}
return(false);
}
void moveVertically(ref FixVec2 deltaMovement)
{
var isGoingUp = deltaMovement.y > 0;
var rayDistance = FixMath.Abs(deltaMovement.y) + _skinWidth;
var rayDirection = isGoingUp ? FixVec2.up : -FixVec2.up;
var initialRayOrigin = isGoingUp ? _raycastOrigins.topLeft : _raycastOrigins.bottomLeft;
// apply our horizontal deltaMovement here so that we do our raycast from the actual position we would be in if we had moved
initialRayOrigin.x += deltaMovement.x;
// if we are moving up, we should ignore the layers in oneWayPlatformMask
var mask = platformMask;
if ((isGoingUp && !collisionState.wasGroundedLastFrame) || ignoreOneWayPlatformsThisFrame)
{
mask &= ~oneWayPlatformMask;
}
for (var i = 0; i < totalVerticalRays; i++)
{
FixVec2 ray = new FixVec2(initialRayOrigin.x + i * _horizontalDistanceBetweenRays, initialRayOrigin.y);
DrawRay((Vector3)ray, (Vector3)(rayDirection * rayDistance), Color.red);
_raycastHit = TFPhysics.Raycast(ray, rayDirection, rayDistance, mask);
if (_raycastHit)
{
// set our new deltaMovement and recalculate the rayDistance taking it into account
deltaMovement.y = _raycastHit.point.y - ray.y;
rayDistance = FixMath.Abs(deltaMovement.y);
// remember to remove the skinWidth from our deltaMovement
if (isGoingUp)
{
deltaMovement.y -= _skinWidth;
collisionState.above = true;
}
else
{
deltaMovement.y += _skinWidth;
collisionState.below = true;
}
_raycastHitsThisFrame.Add(_raycastHit);
// this is a hack to deal with the top of slopes. if we walk up a slope and reach the apex we can get in a situation
// where our ray gets a hit that is less then skinWidth causing us to be ungrounded the next frame due to residual velocity.
if (!isGoingUp && deltaMovement.y > Fix.zero)
{
_isGoingUpSlope = true;
}
// we add a small fudge factor for the float operations here. if our rayDistance is smaller
// than the width + fudge bail out because we have a direct impact
if (rayDistance < _skinWidth + kSkinWidthFloatFudgeFactor)
{
break;
}
}
}
}
private void Update()
{
if (Input.GetMouseButtonDown(0))
{
var v3 = Input.mousePosition;
v3.z = 0;
v3 = Camera.main.ScreenToWorldPoint(v3);
FixVec2 pointB = new FixVec2((Fix)v3.x, (Fix)v3.y);
TFRaycastHit2D h = TFPhysics.Raycast((FixVec2)tfTransform.Position, (FixVec2)(pointB - tfTransform.Position).Normalized(), 5, platformMask);
}
}
/// <summary>
/// checks the center point under the BoxCollider2D for a slope. If it finds one then the deltaMovement is adjusted so that
/// the player stays grounded and the slopeSpeedModifier is taken into account to speed up movement.
/// </summary>
/// <param name="deltaMovement">Delta movement.</param>
private void handleVerticalSlope(ref FixVec2 deltaMovement)
{
// slope check from the center of our collider
Fix centerOfCollider = (_raycastOrigins.bottomLeft.x + _raycastOrigins.bottomRight.x) * (Fix.one / 2);
FixVec2 rayDirection = -FixVec2.up;
// the ray distance is based on our slopeLimit
Fix slopeCheckRayDistance = _slopeLimitTangent * (_raycastOrigins.bottomRight.x - centerOfCollider);
FixVec2 slopeRay = new FixVec2(centerOfCollider, _raycastOrigins.bottomLeft.y);
_raycastHit = TFPhysics.Raycast(slopeRay, rayDirection, slopeCheckRayDistance, platformMask);
if (_raycastHit)
{
// bail out if we have no slope
var angle = FixVec2.Angle(_raycastHit.normal, FixVec2.up);
if (angle == 0)
{
return;
}
// we are moving down the slope if our normal and movement direction are in the same x direction
var isMovingDownSlope = FixMath.Sign(_raycastHit.normal.x) == FixMath.Sign(deltaMovement.x);
if (isMovingDownSlope)
{
// going down we want to speed up in most cases so the slopeSpeedMultiplier curve should be > 1 for negative angles
Fix slopeModifier = (Fix)slopeSpeedMultiplier.Evaluate((float)-angle);
// we add the extra downward movement here to ensure we "stick" to the surface below
deltaMovement.y += _raycastHit.point.y - slopeRay.y - skinWidth;
deltaMovement = new FixVec2(deltaMovement.x, deltaMovement.y)
+ new FixVec2(deltaMovement.x * slopeModifier * (1 - (angle / 90)), (deltaMovement.x * slopeModifier * (angle / 90)));
collisionState.movingDownSlope = true;
collisionState.slopeAngle = angle;
}
}
}
internal TFRaycastHit2D Raycast(ITreeRaycastCallback callback, FixVec2 pointA, FixVec2 pointB, TFLayerMask mask)
{
TFRaycastHit2D hit = new TFRaycastHit2D();
FixVec2 r = pointB - pointA;
if (r.GetMagnitudeSquared() <= Fix.zero)
{
return(hit);
}
r.Normalize();
// v is perpendicular to the segment.
FixVec2 v = FixVec2.Cross(Fix.one, r);
FixVec2 abs_v = FixVec2.Abs(v);
// Separating axis for segment (Gino, p80).
// |dot(v, p1 - c)| > dot(|v|, h)
Fix maxFraction = Fix.one;
// Build a bounding box for the segment.
AABB segmentAABB = new AABB();
FixVec2 t = pointA + maxFraction * (pointB - pointA);
segmentAABB.min = FixVec2.Min(pointA, t);
segmentAABB.max = FixVec2.Max(pointA, t);
Stack <int> stack = new Stack <int>();
stack.Push(rootIndex);
List <TFRaycastOutput> hitNodes = new List <TFRaycastOutput>(2);
while (stack.Count > 0)
{
var nodeId = stack.Pop();
if (nodeId == nullNode)
{
continue;
}
var node = nodes[nodeId];
if (!node.aabb.Overlaps(segmentAABB))
{
continue;
}
// Separating axis for segment (Gino, p80).
// |dot(v, p1 - c)| > dot(|v|, h)
var c = node.aabb.GetCenter();
var h = node.aabb.GetExtents();
var separation = FixMath.Abs(FixVec2.Dot(v, pointA - c)) - FixVec2.Dot(abs_v, h);
if (separation > Fix.zero)
{
continue;
}
if (node.IsLeaf())
{
// If value is >= 0, then we hit the node.
TFRaycastHit2D rHit;
Fix value = callback.RayCastCallback(pointA, pointB, maxFraction, nodeId, out rHit, mask);
if (value == Fix.zero)
{
// The client has terminated the ray cast.
if (rHit)
{
// We actually hit the node, add it to the list.
hitNodes.Add(new TFRaycastOutput(nodeId, rHit));
}
break;
}
if (value == maxFraction)
{
if (rHit)
{
// We actually hit the node, add it to the list.
hitNodes.Add(new TFRaycastOutput(nodeId, rHit));
}
}
else if (value > Fix.zero)
{
if (rHit)
{
// We actually hit the node, add it to the list.
hitNodes.Add(new TFRaycastOutput(nodeId, rHit));
}
// Update segment bounding box.
maxFraction = value;
FixVec2 g = pointA + maxFraction * (pointB - pointA);
segmentAABB.min = FixVec2.Min(pointA, g);
segmentAABB.max = FixVec2.Max(pointA, g);
}
}
else
{
stack.Push(node.leftChildIndex);
stack.Push(node.rightChildIndex);
}
}
// Decide which node was the closest to the starting point.
Fix closestNode = maxFraction;
for (int i = 0; i < hitNodes.Count; i++)
{
if (hitNodes[i].hit.fraction < closestNode)
{
closestNode = hitNodes[i].hit.fraction;
hit = hitNodes[i].hit;
}
}
return(hit);
}
public virtual bool Raycast(out TFRaycastHit2D hit, FixVec2 pointA, FixVec2 pointB, Fix maxFraction)
{
hit = default;
return(false);
}
public TFRaycastHit2D Raycast(FixVec2 origin, FixVec2 direction, Fix distance, TFLayerMask mask)
{
TFRaycastHit2D hit = dynamicTree.Raycast(this, origin, origin + direction * distance, mask);
return(hit);
}
/// <summary>
/// we have to use a bit of trickery in this one. The rays must be cast from a small distance inside of our
/// collider (skinWidth) to avoid zero distance rays which will get the wrong normal. Because of this small offset
/// we have to increase the ray distance skinWidth then remember to remove skinWidth from deltaMovement before
/// actually moving the player
/// </summary>
void moveHorizontally(ref FixVec2 deltaMovement)
{
var isGoingRight = deltaMovement.x > 0;
var rayDistance = FixMath.Abs(deltaMovement.x) + _skinWidth;
var rayDirection = isGoingRight ? FixVec2.right : -FixVec2.right;
var initialRayOrigin = isGoingRight ? _raycastOrigins.bottomRight : _raycastOrigins.bottomLeft;
for (var i = 0; i < totalHorizontalRays; i++)
{
var ray = new FixVec2(initialRayOrigin.x, initialRayOrigin.y + i * _verticalDistanceBetweenRays);
// if we are grounded we will include oneWayPlatforms only on the first ray (the bottom one). this will allow us to
// walk up sloped oneWayPlatforms.
if (i == 0 && collisionState.wasGroundedLastFrame)
{
_raycastHit = TFPhysics.Raycast(ray, rayDirection, rayDistance, platformMask);
}
else
{
_raycastHit = TFPhysics.Raycast(ray, rayDirection, rayDistance, platformMask & ~oneWayPlatformMask);
}
if (_raycastHit)
{
// the bottom ray can hit a slope but no other ray can so we have special handling for these cases
if (i == 0 && handleHorizontalSlope(ref deltaMovement, FixVec2.Angle(_raycastHit.normal, FixVec2.up)))
{
_raycastHitsThisFrame.Add(_raycastHit);
// if we weren't grounded last frame, that means we're landing on a slope horizontally.
// this ensures that we stay flush to that slope
if (!collisionState.wasGroundedLastFrame)
{
Fix flushDistance = FixMath.Sign(deltaMovement.x) * (_raycastHit.distance - skinWidth);
tfTransform.Position += new FixVec2(flushDistance, 0);
}
break;
}
// set our new deltaMovement and recalculate the rayDistance taking it into account
deltaMovement.x = _raycastHit.point.x - ray.x;
rayDistance = FixMath.Abs(deltaMovement.x);
// remember to remove the skinWidth from our deltaMovement
if (isGoingRight)
{
deltaMovement.x -= _skinWidth;
collisionState.right = true;
}
else
{
deltaMovement.x += _skinWidth;
collisionState.left = true;
}
_raycastHitsThisFrame.Add(_raycastHit);
// we add a small fudge factor for the float operations here. if our rayDistance is smaller
// than the width + fudge bail out because we have a direct impact
if (rayDistance < _skinWidth + kSkinWidthFloatFudgeFactor)
{
break;
}
}
}
}
public static TFRaycastHit2D Raycast(FixVec2 origin, FixVec2 direction, Fix distance, TFLayerMask mask)
{
TFRaycastHit2D hit = physicsScene.Raycast(origin, direction, distance, mask);
return(hit);
}
public override bool Raycast(out TFRaycastHit2D hit, FixVec2 pointA, FixVec2 pointB, Fix maxFraction)
{
hit = new TFRaycastHit2D();
// Put the ray into the polygon's frame of reference.
var p1 = u.Transposed() * (pointA - (FixVec2)tdTransform.Position);
var p2 = u.Transposed() * (pointB - (FixVec2)tdTransform.Position);
var d = p2 - p1;
Fix lower = Fix.zero, upper = maxFraction;
var index = -1;
for (var i = 0; i < vertices.Count; ++i)
{
// p = p1 + a * d
// dot(normal, p - v) = 0
// dot(normal, p1 - v) + a * dot(normal, d) = 0
var numerator = FixVec2.Dot(normals[i], GetVertex(i) - p1);
var denominator = FixVec2.Dot(normals[i], d);
if (denominator == Fix.zero)
{
if (numerator < Fix.zero)
{
return(false);
}
}
else
{
// Note: we want this predicate without division:
// lower < numerator / denominator, where denominator < 0
// Since denominator < 0, we have to flip the inequality:
// lower < numerator / denominator <==> denominator * lower > numerator.
if (denominator < Fix.zero && numerator < lower * denominator)
{
// Increase lower.
// The segment enters this half-space.
lower = numerator / denominator;
index = i;
}
else if (denominator > Fix.zero && numerator < upper * denominator)
{
// Decrease upper.
// The segment exits this half-space.
upper = numerator / denominator;
}
}
// The use of epsilon here causes the assert on lower to trip
// in some cases. Apparently the use of epsilon was to make edge
// shapes work, but now those are handled separately.
//if (upper < lower - b2_epsilon)
if (upper < lower)
{
return(false);
}
}
if (index >= 0)
{
hit.fraction = lower;
hit.normal = tdTransform.Rotation * normals[index];
hit.collider = this;
return(true);
}
return(false);
}
public bool Raycast(FixVec2 pointA, FixVec2 pointB, out TFRaycastHit2D hit)
{
hit = default;
dynamicTree.Raycast(this, pointA, pointB);
return(false);
}
