public override bool ComputeGroundHit(Vector3 position, Quaternion rotation, ref GroundHit groundHitInfo,
float distance = Mathf.Infinity)
{
var up = rotation * Vector3.up;
// Downward cast from capsule's bottom sphere (filter any 'wall')
RaycastHit hitInfo;
if (BottomSphereCast(position, rotation, out hitInfo, distance) && Vector3.Angle(hitInfo.normal, up) < 89.0f)
{
// Update ground hit info
groundHitInfo.SetFrom(hitInfo);
// Check if standing on a ledge or step
DetectLedgeAndSteps(position, rotation, ref groundHitInfo, distance, hitInfo.point, hitInfo.normal);
// Inform we found 'ground' and if is valid
groundHitInfo.isOnGround = true;
groundHitInfo.isValidGround = !groundHitInfo.isOnLedgeEmptySide &&
Vector3.Angle(groundHitInfo.surfaceNormal, up) < groundLimit;
return(true);
}
// If initial sphere cast fails, or found a 'wall',
// fallback to a raycast from character's bottom position
if (!BottomRaycast(position, rotation, out hitInfo, distance))
{
return(false);
}
// If found 'ground', update ground info and return
groundHitInfo.SetFrom(hitInfo);
groundHitInfo.surfaceNormal = hitInfo.normal;
groundHitInfo.isOnGround = true;
groundHitInfo.isValidGround = Vector3.Angle(groundHitInfo.surfaceNormal, /*Vector3.up*/ up) < groundLimit;
return(true);
}
/// <summary>
/// Check if we are standing on a ledge or a step and update 'grounding' info.
/// </summary>
/// <param name="position">A probing position. This can be different from character's position.</param>
/// <param name="rotation">A probing rotation. This can be different from character's rotation.</param>
/// <param name="distance">The cast distance.</param>
/// <param name="point">The current contact point.</param>
/// <param name="normal">The current contact normal.</param>
/// <param name="groundHitInfo">If found any 'ground', hitInfo will contain more information about it.</param>
private void DetectLedgeAndSteps(Vector3 position, Quaternion rotation, ref GroundHit groundHitInfo,
float distance, Vector3 point, Vector3 normal)
{
Vector3 up = rotation * Vector3.up, down = -up;
var projectedNormal = Vector3.ProjectOnPlane(normal, up).normalized;
var nearPoint = point + projectedNormal * kHorizontalOffset;
var farPoint = point - projectedNormal * kHorizontalOffset;
var ledgeStepDistance = Mathf.Max(kMinLedgeDistance, Mathf.Max(stepOffset, distance));
RaycastHit nearHitInfo;
var nearHit = Raycast(nearPoint, down, out nearHitInfo, ledgeStepDistance);
var isNearGroundValid = nearHit && Vector3.Angle(nearHitInfo.normal, up) < groundLimit;
RaycastHit farHitInfo;
var farHit = Raycast(farPoint, down, out farHitInfo, ledgeStepDistance);
var isFarGroundValid = farHit && Vector3.Angle(farHitInfo.normal, up) < groundLimit;
// Flush
if (farHit && !isFarGroundValid)
{
groundHitInfo.surfaceNormal = farHitInfo.normal;
// Attemp to retrieve the 'ground' below us
RaycastHit secondaryHitInfo;
if (BottomRaycast(position, rotation, out secondaryHitInfo, distance))
{
// Update ground info and return
groundHitInfo.SetFrom(secondaryHitInfo);
groundHitInfo.surfaceNormal = secondaryHitInfo.normal;
}
return;
}
// Steps
if (isNearGroundValid && isFarGroundValid)
{
// Choose nearest normal
groundHitInfo.surfaceNormal =
(point - nearHitInfo.point).sqrMagnitude < (point - farHitInfo.point).sqrMagnitude
? nearHitInfo.normal
: farHitInfo.normal;
// Check if max vertical distance between points is steep enough to be considered as a step
var nearHeight = Vector3.Dot(point - nearHitInfo.point, up);
var farHeight = Vector3.Dot(point - farHitInfo.point, up);
var height = Mathf.Max(nearHeight, farHeight);
if (height > kMinLedgeDistance && height < stepOffset)
{
groundHitInfo.isOnStep = true;
groundHitInfo.stepHeight = height;
}
return;
}
// Ledges
// If only one of the near / far rays hit we are on a ledge
var isOnLedge = isNearGroundValid != isFarGroundValid;
if (!isOnLedge)
{
return;
}
// On ledge, compute ledge info and check which side of the ledge we are
groundHitInfo.surfaceNormal = isFarGroundValid ? farHitInfo.normal : nearHitInfo.normal;
groundHitInfo.ledgeDistance = Vector3.ProjectOnPlane(point - position, up).magnitude;
if (isFarGroundValid && groundHitInfo.ledgeDistance > ledgeOffset)
{
// On possible ledge 'empty' side,
// cast downwards using de ledgeOffset as radius
groundHitInfo.isOnLedgeEmptySide = true;
var radius = ledgeOffset;
var offset = Mathf.Max(0.0f, capsuleCollider.height * 0.5f - radius);
var bottomSphereCenter = capsuleCollider.center - Vector3.up * offset;
var bottomSphereOrigin = position + rotation * bottomSphereCenter;
RaycastHit hitInfo;
if (SphereCast(bottomSphereOrigin, radius, down, out hitInfo, Mathf.Max(stepOffset, distance)))
{
var verticalSquareDistance = Vector3.Project(point - hitInfo.point, up).sqrMagnitude;
if (verticalSquareDistance <= stepOffset * stepOffset)
{
groundHitInfo.isOnLedgeEmptySide = false;
}
}
}
groundHitInfo.isOnLedgeSolidSide = !groundHitInfo.isOnLedgeEmptySide;
}
