public Q3BSPCollisionData TraceRay(Vector3 startPosition, Vector3 endPosition) { Q3BSPCollisionData collision = new Q3BSPCollisionData(); collision.type = Q3BSPCollisionType.Ray; return(Trace(startPosition, endPosition, ref collision)); }
public Q3BSPCollisionData TraceSphere(Vector3 startPosition, Vector3 endPosition, float sphereRadius) { Q3BSPCollisionData collision = new Q3BSPCollisionData(); collision.type = Q3BSPCollisionType.Sphere; collision.sphereRadius = sphereRadius; return(Trace(startPosition, endPosition, ref collision)); }
public Q3BSPCollisionData TraceBox(Vector3 startPosition, Vector3 endPosition, Vector3 boxMinimums, Vector3 boxMaximums) { Q3BSPCollisionData collision = new Q3BSPCollisionData(); if (boxMinimums.X == 0 && boxMinimums.Y == 0 && boxMinimums.Z == 0 && boxMaximums.X == 0 && boxMaximums.Y == 0 && boxMaximums.Z == 0) { collision.type = Q3BSPCollisionType.Ray; return(Trace(startPosition, endPosition, ref collision)); } if (boxMaximums.X < boxMinimums.X) { float x = boxMaximums.X; boxMaximums.X = boxMinimums.X; boxMinimums.X = x; } if (boxMaximums.Y < boxMinimums.Y) { float y = boxMaximums.Y; boxMaximums.Y = boxMinimums.Y; boxMinimums.Y = y; } if (boxMaximums.Z < boxMinimums.Z) { float z = boxMaximums.Z; boxMaximums.Z = boxMinimums.Z; boxMinimums.Z = z; } Vector3 boxExtents = new Vector3(); boxExtents.X = Math.Max(Math.Abs(boxMaximums.X), Math.Abs(boxMinimums.X)); boxExtents.Y = Math.Max(Math.Abs(boxMaximums.Y), Math.Abs(boxMinimums.Y)); boxExtents.Z = Math.Max(Math.Abs(boxMaximums.Z), Math.Abs(boxMinimums.Z)); collision.type = Q3BSPCollisionType.Box; collision.boxMinimums = boxMinimums; collision.boxMaximums = boxMaximums; collision.boxExtents = boxExtents; return(Trace(startPosition, endPosition, ref collision)); }
private Q3BSPCollisionData Trace(Vector3 startPosition, Vector3 endPosition, ref Q3BSPCollisionData collision) { collision.startOutside = true; collision.inSolid = false; collision.ratio = 1.0f; collision.startPosition = startPosition; collision.endPosition = endPosition; collision.collisionPoint = startPosition; WalkNode(0, 0.0f, 1.0f, startPosition, endPosition, ref collision); if (1.0f == collision.ratio) { collision.collisionPoint = endPosition; } else { collision.collisionPoint = startPosition + (collision.ratio - 0.002f) * (endPosition - startPosition); } return(collision); }
private void CheckBrush(ref Q3BSPBrush brush, ref Q3BSPCollisionData cd) { float startFraction = -1.0f; float endFraction = 1.0f; bool startsOut = false; bool endsOut = false; for (int i = 0; i < brush.NumberOfSides; i++) { Q3BSPBrushSide brushSide = brushSides[brush.StartBrushSide + i]; Plane plane = planes[brushSide.PlaneIndex]; float startDistance = 0, endDistance = 0; if (cd.type == Q3BSPCollisionType.Ray) { startDistance = Vector3.Dot(cd.startPosition, plane.Normal) - plane.D; endDistance = Vector3.Dot(cd.endPosition, plane.Normal) - plane.D; } else if (cd.type == Q3BSPCollisionType.Sphere) { startDistance = Vector3.Dot(cd.startPosition, plane.Normal) - (plane.D + cd.sphereRadius); endDistance = Vector3.Dot(cd.endPosition, plane.Normal) - (plane.D + cd.sphereRadius); } else if (cd.type == Q3BSPCollisionType.Box) { Vector3 offset = new Vector3(); if (plane.Normal.X < 0) { offset.X = cd.boxMaximums.X; } else { offset.X = cd.boxMinimums.X; } if (plane.Normal.Y < 0) { offset.Y = cd.boxMaximums.Y; } else { offset.Y = cd.boxMinimums.Y; } if (plane.Normal.Z < 0) { offset.Z = cd.boxMaximums.Z; } else { offset.Z = cd.boxMinimums.Z; } startDistance = (cd.startPosition.X + offset.X) * plane.Normal.X + (cd.startPosition.Y + offset.Y) * plane.Normal.Y + (cd.startPosition.Z + offset.Z) * plane.Normal.Z - plane.D; endDistance = (cd.endPosition.X + offset.X) * plane.Normal.X + (cd.endPosition.Y + offset.Y) * plane.Normal.Y + (cd.endPosition.Z + offset.Z) * plane.Normal.Z - plane.D; } if (startDistance > 0) { startsOut = true; } if (endDistance > 0) { endsOut = true; } if (startDistance > 0 && endDistance > 0) { return; } if (startDistance <= 0 && endDistance <= 0) { continue; } if (startDistance > endDistance) { float fraction = (startDistance - Q3BSPConstants.Epsilon) / (startDistance - endDistance); if (fraction > startFraction) { startFraction = fraction; } } else { float fraction = (startDistance + Q3BSPConstants.Epsilon) / (startDistance - endDistance); if (fraction < endFraction) { endFraction = fraction; } } } if (false == startsOut) { cd.startOutside = false; if (false == endsOut) { cd.inSolid = true; } return; } if (startFraction < endFraction) { if (startFraction > -1.0f && startFraction < cd.ratio) { if (startFraction < 0) { startFraction = 0; } cd.ratio = startFraction; } } }
private void WalkNode(int nodeIndex, float startRatio, float endRatio, Vector3 startPosition, Vector3 endPosition, ref Q3BSPCollisionData cd) { // Is this a leaf? if (0 > nodeIndex) { Q3BSPLeaf leaf = leafs[-(nodeIndex + 1)]; for (int i = 0; i < leaf.LeafBrushCount; i++) { Q3BSPBrush brush = brushes[leafBrushes[leaf.StartLeafBrush + i]]; if (0 < brush.NumberOfSides && 1 == (textureData[brush.TextureIndex].Contents & 1)) { CheckBrush(ref brush, ref cd); } } return; } // This is a node Q3BSPNode thisNode = nodes[nodeIndex]; Plane thisPlane = planes[thisNode.Plane]; float startDistance = Vector3.Dot(startPosition, thisPlane.Normal) - thisPlane.D; float endDistance = Vector3.Dot(endPosition, thisPlane.Normal) - thisPlane.D; float offset = 0; // Set offset for sphere-based collision if (cd.type == Q3BSPCollisionType.Sphere) { offset = cd.sphereRadius; } // Set offest for box-based collision if (cd.type == Q3BSPCollisionType.Box) { offset = Math.Abs(cd.boxExtents.X * thisPlane.Normal.X) + Math.Abs(cd.boxExtents.Y * thisPlane.Normal.Y) + Math.Abs(cd.boxExtents.Z * thisPlane.Normal.Z); } if (startDistance >= offset && endDistance >= offset) { // Both points are in front WalkNode(thisNode.Left, startRatio, endRatio, startPosition, endPosition, ref cd); } else if (startDistance < -offset && endDistance < -offset) { WalkNode(thisNode.Right, startRatio, endRatio, startPosition, endPosition, ref cd); } else { // The line spans the splitting plane int side = 0; float fraction1 = 0.0f; float fraction2 = 0.0f; float middleFraction = 0.0f; Vector3 middlePosition = new Vector3(); if (startDistance < endDistance) { side = 1; float inverseDistance = 1.0f / (startDistance - endDistance); fraction1 = (startDistance - offset + Q3BSPConstants.Epsilon) * inverseDistance; fraction2 = (startDistance + offset + Q3BSPConstants.Epsilon) * inverseDistance; } else if (endDistance < startDistance) { side = 0; float inverseDistance = 1.0f / (startDistance - endDistance); fraction1 = (startDistance + offset + Q3BSPConstants.Epsilon) * inverseDistance; fraction2 = (startDistance - offset - Q3BSPConstants.Epsilon) * inverseDistance; } else { side = 0; fraction1 = 1.0f; fraction2 = 0.0f; } if (fraction1 < 0.0f) { fraction1 = 0.0f; } else if (fraction1 > 1.0f) { fraction1 = 1.0f; } if (fraction2 < 0.0f) { fraction2 = 0.0f; } else if (fraction2 > 1.0f) { fraction2 = 1.0f; } middleFraction = startRatio + (endRatio - startRatio) * fraction1; middlePosition = startPosition + fraction1 * (endPosition - startPosition); int side1; int side2; if (0 == side) { side1 = thisNode.Left; side2 = thisNode.Right; } else { side1 = thisNode.Right; side2 = thisNode.Left; } WalkNode(side1, startRatio, middleFraction, startPosition, middlePosition, ref cd); middleFraction = startRatio + (endRatio - startRatio) * fraction2; middlePosition = startPosition + fraction2 * (endPosition - startPosition); WalkNode(side2, middleFraction, endRatio, middlePosition, endPosition, ref cd); } }