// constructor
public Sphere(Position3 position, double radius, bool useNormalMap, CreatePositionDelegate createPosition, CreateTerrainNodeVertexBufferDelegate createTerrainNodeVertexBuffer, bool isSphere)
{
this.position = position;
this.Radius = radius;
this.useNormalMap = useNormalMap;
this.createPosition = createPosition;
this.createTerrainNodeVertexBuffer = createTerrainNodeVertexBuffer;
this.isSphere = isSphere;
Initialize();
}
public static double CreatePositionSphere(ref Position3 spherePosition, ref Position3 cubePosition, ref Vector2 patchPosition,
double radius, out Position3 outPosition)
{
// the input position is a point on the surface of a unit sphere
// by default we just want to move it out to the sphere radius
// descendant classes will do more interesting things, like add some perlin noise
// to it for terrain
outPosition = spherePosition * radius;
return 0;
}
public static double CreatePositionPlanet(ref Position3 spherePosition, ref Position3 cubePosition, ref Vector2 patchPosition,
double radius, out Position3 outPosition)
{
Position3 p = cubePosition * 1.2;
double h0 = Math.Abs(Noise.fBm(p.X, p.Y, p.Z, 3)) / 10.0;
double h1 = Noise.Turbulence(p.X, p.Y, p.Z, 3, 2.0, 0.5);
double h2 = Noise.HybridMultiFractal(p.X, p.Y, p.Z, 14, 1.854143, h0, 0.60);
double h = h1 * h2;
h *= 60;
outPosition = spherePosition * (radius + h);
return h;
}
/// <summary>
/// Determine if the node needs to be split based on camera distance and field of view
/// </summary>
/// <param name="cameraPosition">Planet-space camera position </param>
/// <param name="fieldOfView">Camera's field of view</param>
/// <returns>True if the terrain node needs to be split</returns>
private bool NeedsSplit(Position3 planetPosition, Position3 cameraPosition, float fieldOfView)
{
// limit splitting
if (isSphere && level >= Constants.MaxAtmosphereNodeLevel) return false;
if (!isSphere && level >= Constants.MaxTerrainNodeLevel) return false;
// get distance between camera and terrain node center - both are already in planet space
float viewDistance = GetViewDistance(planetPosition, cameraPosition);
// TODO : splitting not working properly when zooming in/out - seems to be the opposite of what's needed
// calculate screen space error
float k = 1024.0f * 0.5f * (float)Math.Tan(fieldOfView * 0.5f);
float screenSpaceError = (geometricError / viewDistance) * k;
// return true if the screen space error is greater than the max
return (screenSpaceError > maxScreenSpaceError);
}
/// <summary>
/// Get distance from camera
/// </summary>
/// <param name="planetPosition">Position of planet center</param>
/// <param name="cameraPosition">Camera position in planet space</param>
/// <returns></returns>
private float GetViewDistance(Position3 planetPosition, Position3 cameraPosition)
{
//return (float)Position3.Distance(this.Position, cameraPosition);
// need to get the camera position in patch-space to compare the distance
Vector3 v = (cameraPosition - this.Position).AsVector3;
// translate to object space by adding patch position to planet position then subtracting from the camera position
//Vector3 v = (cameraPosition - (planetPosition + this.position)).AsVector3;
float minDistance = 999999999999;
closestPosition = new Position3(vertexBuffer.Vertices[MapVertexIndex(Constants.PatchWidth / 2, Constants.PatchHeight / 2)].Position);
// center center
CheckDistance(Constants.PatchWidth / 2, Constants.PatchHeight / 2, ref v, ref minDistance);
// bottom left
CheckDistance(0, 0, ref v, ref minDistance);
// bottom center
CheckDistance(Constants.PatchWidth / 2, 0, ref v, ref minDistance);
// bottom right
CheckDistance(Constants.PatchWidth - 1, 0, ref v, ref minDistance);
// top left
CheckDistance(0, Constants.PatchHeight - 1, ref v, ref minDistance);
// top center
CheckDistance(Constants.PatchWidth / 2, Constants.PatchHeight - 1, ref v, ref minDistance);
// top right
CheckDistance(Constants.PatchWidth - 1, Constants.PatchHeight - 1, ref v, ref minDistance);
// left center
CheckDistance(0, Constants.PatchHeight / 2, ref v, ref minDistance);
// right center
CheckDistance(Constants.PatchWidth - 1, Constants.PatchHeight / 2, ref v, ref minDistance);
// transform to planet-space
closestPosition += this.Position;
// return closest distance
return (float)Math.Sqrt(minDistance);
}
public void Subtract(ref Position3 V1, ref Position3 V2)
{
X = V1.X - V2.X;
Y = V1.Y - V2.Y;
Z = V1.Z - V2.Z;
}
public void Update(Position3 cameraPosition, float fieldOfView)
{
// update nodes, allowing them to split if required
front.Update(position, cameraPosition, fieldOfView);
back.Update(position, cameraPosition, fieldOfView);
left.Update(position, cameraPosition, fieldOfView);
right.Update(position, cameraPosition, fieldOfView);
top.Update(position, cameraPosition, fieldOfView);
bottom.Update(position, cameraPosition, fieldOfView);
}
/// <summary>
/// Calculate angle from camera to horizon
/// </summary>
/// <param name="cameraPosition">Planet space camera position</param>
/// <returns>Horizon angle in radians</returns>
public float CalculateHorizonAngle(Position3 cameraPosition)
{
double result = MathHelper.ToRadians(300);
double h = cameraPosition.Length();
if (h > radius)
{
result = Math.Acos(radius / h);
result += MathHelper.ToRadians(5); // add 5 degrees to account for mountains on the horizon
// if we're fairly far away from the planet we need to account
// for the very large patch size of the 6 faces that make up the planet
h = h - radius - 9;
if (h > 1000)
result += MathHelper.ToRadians(50);
}
return (float)result;
}
public void Clone(Movement movement)
{
Orientation = movement.Orientation;
fLocalPosition = movement.fLocalPosition;
UpdateMovement(0);
}
/// <summary>
/// Split this node's children
/// </summary>
/// <param name="cameraPosition">Planet-space camera position</param>
/// <param name="fieldOfView">Camera's field of view</param>
private void SplitChildren(Position3 planetPosition, Position3 cameraPosition, float fieldOfView)
{
if (HasChildren)
{
children[0].Split(planetPosition, cameraPosition, fieldOfView);
children[1].Split(planetPosition, cameraPosition, fieldOfView);
children[2].Split(planetPosition, cameraPosition, fieldOfView);
children[3].Split(planetPosition, cameraPosition, fieldOfView);
}
}
public Vector3[] GetHeightAndNormal(Position3 position, out double height, out Vector3 normal)
{
// we know position is over this node, now we need to find which triangle within the node
// normalize the position so it points out from the planet center towards the actual position
position.Normalize();
// get the direction vector
Position3 direction3 = position;
Vector3 direction = position.AsVector3;
// get a position 1km under the planet surface, in planet space
position *= radius - 1;
// translate to patch space
position -= this.Position;
// get ray from position to planet center, translate to patch space
Ray ray = new Ray(position.AsVector3, direction);
float? intersection = null;
float u = 0;
float v = 0;
Vector3 v0 = Vector3.Zero;
Vector3 v1 = Vector3.Zero;
Vector3 v2 = Vector3.Zero;
Vector3 v4 = Vector3.Zero;
Vector3 n0 = Vector3.Zero;
Vector3 n1 = Vector3.Zero;
Vector3 n2 = Vector3.Zero;
Vector3 n4 = Vector3.Zero;
int triangleIndex = 0;
int quadIndex = 0;
int index;
int y;
int x;
// now we need to loop through each triangle and see if the ray intersects
for (int i = 0; i < TerrainNodeIndexBuffer.IndexCount; i += 3)
{
index = TerrainNodeIndexBuffer.IndexData[i];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v0 = vertexBuffer.Vertices[index].Position;
n0 = vertexBuffer.Vertices[index].Normal;
index = TerrainNodeIndexBuffer.IndexData[i + 1];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v1 = vertexBuffer.Vertices[index].Position;
n1 = vertexBuffer.Vertices[index].Normal;
index = TerrainNodeIndexBuffer.IndexData[i + 2];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v2 = vertexBuffer.Vertices[index].Position;
n2 = vertexBuffer.Vertices[index].Normal;
Tools.RayIntersectsTriangle(ref ray, ref v0, ref v1, ref v2, out intersection, out u, out v);
if (intersection != null)
{
triangleIndex = i;
quadIndex = i;
if (quadIndex % 6 != 0)
quadIndex -= 3;
break;
}
}
Globals.TriangleIndex = triangleIndex;
if (intersection == null)
{
height = radius;
normal = direction;
return null;
}
// Now that we've calculated the indices of the corners of our cell, and
// where we are in that cell, we'll use bilinear interpolation to calculuate
// our height. This process is best explained with a diagram, so please see
// the accompanying doc for more information.
// First, calculate the heights on the bottom and top edge of our cell by
// interpolating from the left and right sides.
// get the vertices for the quad containing this triangle
index = TerrainNodeIndexBuffer.IndexData[quadIndex + 0];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v0 = vertexBuffer.Vertices[index].Position;
n0 = vertexBuffer.Vertices[index].Normal;
index = TerrainNodeIndexBuffer.IndexData[quadIndex + 1];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v1 = vertexBuffer.Vertices[index].Position;
n1 = vertexBuffer.Vertices[index].Normal;
index = TerrainNodeIndexBuffer.IndexData[quadIndex + 2];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v2 = vertexBuffer.Vertices[index].Position;
n2 = vertexBuffer.Vertices[index].Normal;
index = TerrainNodeIndexBuffer.IndexData[quadIndex + 4];
y = index / Constants.PatchHeight;
x = index % Constants.PatchWidth;
index = (y + 1) * patchColumns + (x + 1);
v4 = vertexBuffer.Vertices[index].Position;
n4 = vertexBuffer.Vertices[index].Normal;
/*
Vector3 top, bottom, p, topNormal, bottomNormal, n;
if (triangleIndex % 6 == 0)
{
// we're in triangle A - the top left triangle
top = Vector3.Lerp(v0, v1, u);
bottom = Vector3.Lerp(v2, v4, u);
p = Vector3.Lerp(top, bottom, v);
topNormal = Vector3.Lerp(n0, n1, u);
bottomNormal = Vector3.Lerp(n2, n4, u);
n = Vector3.Lerp(topNormal, bottomNormal, v);
n.Normalize();
}
else
{
// we're in triangle B - the bottom right triangle
// this means u and v are positions within *that* triangle, so we need to do our lerping differently
// we're in triangle A - the top left triangle
// TODO : except u and v are acting very odd! they don't seem to be correct
// let's try getting the quad all at once, then doing the Ray check on each triangle in the quad
top = Vector3.Lerp(v0, v1, u);
bottom = Vector3.Lerp(v2, v4, u);
p = Vector3.Lerp(top, bottom, v);
topNormal = Vector3.Lerp(n0, n1, u);
bottomNormal = Vector3.Lerp(n2, n4, u);
n = Vector3.Lerp(topNormal, bottomNormal, v);
n.Normalize();
}
*/
// intersection gives us the length on the ray of the exact intersection position,
// which gives us the exact height value to use
Position3 vp = this.Position + (position + (direction3 * (double)intersection));
height = vp.Length();
// but now, how do we get the normal from that? let's start with just averaging the normals
normal = (n0 + n1 + n2 + n4) * 0.25f;
Vector3[] result = new Vector3[5];
result[0] = v0;
result[1] = v1;
result[2] = v2;
result[3] = v4;
result[4] = (vp - this.Position).AsVector3;
return result;
}
/// <summary>
/// Generate terrain mesh for this node
/// </summary>
public void GenerateMesh(TerrainNodeSplitItem item)
{
// the minus one here is correct: e.g. 3x3 vertices labeled 0, 1, 2: v0.x = 0, v1.x = 0.5, v2.x = 1. The increment = 1 / (3 - 1) = 0.5
double horizontalStep = bounds.Width / (Constants.PatchWidth - 1);
double verticalStep = bounds.Height / (Constants.PatchHeight - 1);
float horizontalTextureStep = 1.0f / (Constants.PatchWidth - 1);
float verticalTextureStep = 1.0f / (Constants.PatchHeight - 1);
float MinX, MinY, MinZ;
float MaxX, MaxY, MaxZ;
// initialize min and max vertex tracking
MinX = MinY = MinZ = 999999;
MaxX = MaxY = MaxZ = -999999;
// get matrix used to transform vertices to the proper cube face
Matrix faceMatrix = CubeFaces.GetFace(bounds.Face).FaceMatrix;
// create vertex storage using user supplied delegate
vertexBuffer = createTerrainNodeVertexBuffer(item.HeightData.Length);
//int cubeVertexIndex = 0;
//CubeVertices = new Vector2[item.HeightData.Length];
hasMeshBorder = false;
int vertexIndex = 0;
int Rows = Constants.PatchHeight;
int Columns = Constants.PatchWidth;
if (item.HeightData.Length > Constants.PatchWidth * Constants.PatchHeight)
{
hasMeshBorder = true;
Rows += 2;
Columns += 2;
}
patchRows = Rows;
patchColumns = Columns;
float v = 0;
double y = bounds.Bottom;
if (hasMeshBorder)
{
v -= verticalTextureStep;
y -= verticalStep;
}
for (int hy = 0; hy < Rows; hy++)
{
float u = 0;
double x = bounds.Left;
if (hasMeshBorder)
{
u -= horizontalTextureStep;
x -= horizontalStep;
}
for (int hx = 0; hx < Columns; hx++)
{
// create the vertex position and rotate it to the appropriate face
Position3 cubePosition = new Position3(x, y, 1);
Position3 spherePosition = Tools.CubeToSphereMapping(x, y, 1);
spherePosition.Transform(ref faceMatrix);
cubePosition.Transform(ref faceMatrix);
// transform the vertex based on the user defined delegate
double height;
Position3 finalPosition;
Vector2 patchPosition = new Vector2(hx, hy);
if (item == null)
CreatePosition(ref spherePosition, ref cubePosition, ref patchPosition, out finalPosition, out height);
else
{
height = item.HeightData[hy * Columns + hx];
if (height < 0) height = 0;
finalPosition = spherePosition * (radius + height);
TranslateToPatchSpace(ref finalPosition);
}
VertexPositionNormalTextureHeight vertex = new VertexPositionNormalTextureHeight();
vertex.Position = (Vector3)finalPosition;
vertex.Height = (float)height;
vertex.Normal = (Vector3)spherePosition;
vertex.TextureCoordinate = new Vector2(u, v);
vertex.Tangent = Vector4.Zero;
vertexBuffer.Vertices[vertexIndex++] = vertex;
// track min and max coordinates, but only for the vertices that will be in the final mesh
if (hx >= 1 && hx < Columns - 1 && hy >= 1 && hy < Rows - 1)
{
if (vertex.Position.X < MinX) MinX = vertex.Position.X;
if (vertex.Position.Y < MinY) MinY = vertex.Position.Y;
if (vertex.Position.Z < MinZ) MinZ = vertex.Position.Z;
if (vertex.Position.X > MaxX) MaxX = vertex.Position.X;
if (vertex.Position.Y > MaxY) MaxY = vertex.Position.Y;
if (vertex.Position.Z > MaxZ) MaxZ = vertex.Position.Z;
}
x += horizontalStep;
u += horizontalTextureStep;
}
y += verticalStep;
v += verticalTextureStep;
}
// create min and max bounding vertices, in patch-space
minVertex = new Vector3(MinX, MinY, MinZ);
maxVertex = new Vector3(MaxX, MaxY, MaxZ);
// calculate normals and tangents
CalculateNormals();
CalculateTangents();
// save vertex buffer changes - this effectively copies the raw data to a vertex buffer on the device
vertexBuffer.CommitChanges(Constants.PatchWidth, Constants.PatchHeight);
}
// face space method, using ray intersection in planet space
public TerrainNode FindNodeUnderPosition(Position3 position, out Vector3[] triangle, out double height, out Vector3 normal)
{
triangle = null;
height = 0;
normal = Vector3.Zero;
Position3 originalPosition = position;
// normalize the position so it points out from the planet center towards the actual position
position.Normalize();
// get the direction vector
Vector3 direction = position.AsVector3;
// get a position 1km under the planet surface
position *= radius - 1;
// get ray from position to planet center, translate to patch space
Ray ray = new Ray((position - this.Position).AsVector3, direction);
Vector3 p1 = MinVertex;
Vector3 p2 = MaxVertex;
// first do a bounding box/ray intersection test
BoundingBox box = new BoundingBox(MinVertex, MaxVertex);
// if the ray doesn't intersect the bounding box then it can't intersect terrain node
if (ray.Intersects(box) == null) return null;
// we have a potential match - do mesh collision to be sure
Vector3[] t = this.GetHeightAndNormal(originalPosition, out height, out normal);
// if no mesh collision then we're done
if (t == null) return null;
// if the position is over this node and this is a leaf node then we have what we want
if (!HasChildren)
{
triangle = t;
return this;
}
// otherwise we want to recurse into the children to find the leaf node
for (int i = 0; i < children.Length; i++)
{
TerrainNode node = children[i].FindNodeUnderPosition(position, out triangle, out height, out normal);
if (node != null) return node;
}
// if we get here then we have a problem - the position is allegedly above this node, which means
// it should also be above one of this node's children, but we didn't find a child
// return this;
if (Globals.Game.Graphics.IsFullScreen)
Globals.Game.Graphics.ToggleFullScreen();
throw new Exception("Unable to find leaf node.");
}
public Position3(Position3 V)
{
X = V.X;
Y = V.Y;
Z = V.Z;
}
public void SubtractNormalize(ref Position3 V1, ref Vector3 V2)
{
X = V1.X - V2.X;
Y = V1.Y - V2.Y;
Z = V1.Z - V2.Z;
double L = 1 / Math.Sqrt(X * X + Y * Y + Z * Z);
X *= L;
Y *= L;
Z *= L;
}
public void SubtractFrom(ref Position3 V1)
{
X = V1.X - X;
Y = V1.Y - Y;
Z = V1.Z - Z;
}
public void Subtract(ref Position3 V1)
{
X -= V1.X;
Y -= V1.Y;
Z -= V1.Z;
}
/// <summary>
/// Split or unsplit nodes and child nodes as required
/// </summary>
/// <param name="cameraPosition">Planet-space camera position</param>
/// <param name="fieldOfView">Camera's field of view</param>
private void Split(Position3 planetPosition, Position3 cameraPosition, float fieldOfView)
{
// if we're already splitting then we don't want to do any other split processing until the thread is complete
// this node will continue to be the leaf node in this branch so it will continue to draw until the
// splitting is completed
if (Splitting)
{
// if we no longer need to split, but we're still queued up for splitting then cancel it - the thread
// will see this when it gets to the the node in the queue and won't do anything
if (!NeedsSplit(planetPosition, cameraPosition, fieldOfView))
CancelSplitting = true;
return;
}
// if this node needs to be split then check its children or queue up a split
if (NeedsSplit(planetPosition, cameraPosition, fieldOfView))
{
// if it already has children then we've already split, so recurse through the children
if (HasChildren)
{
SplitChildren(planetPosition, cameraPosition, fieldOfView);
}
// otherwise we need to be split and have no children, so queue up the child node to the node splitter queue thread
else
{
// setting this will cause drawing code to pretend this is a leaf node until the split is complete
// it will also become non-splittable during this time
CancelSplitting = false;
Splitting = true;
QueueNodeGeneration();
}
}
// if we don't need to be split then we can remove child nodes
else
{
// if our children are all leaf nodes then we no longer need them, so get rid of them and this node is now a leaf node
if (ChildrenAreLeafNodes())
ClearChildren();
// if we do have non-leaf children then recurse down until we find a node whose children are leaves, and remove those children
// the lower level children will continue to be drawn until they've been cleared out, at only 1 level per frame
if (HasChildren)
SplitChildren(planetPosition, cameraPosition, fieldOfView);
}
}
/// <summary>
/// Split all the way down to leaf nodes before generating the actual terrain.
/// The deepest node with data will still be displayed until all the leaf nodes
/// are ready.
/// </summary>
/// <param name="planetPosition"></param>
/// <param name="cameraPosition"></param>
/// <param name="fieldOfView"></param>
private void Split2(Position3 planetPosition, Position3 cameraPosition, float fieldOfView)
{
}
/// <summary>
/// Translate sphere-space position to patch-space
/// </summary>
/// <param name="position">Sphere-space position</param>
public void TranslateToPatchSpace(ref Position3 position)
{
position.Subtract(ref this.position);
}
public void UpdateMovement(float elapsed)
{
fRotationalVelocity += (fRotationalAcceleration * elapsed);
fRotationTime += elapsed;
while (fRotationTime >= (1.0f / 60.0f))
{
fRotationalVelocity *= fRotationalDrag;
fRotationTime -= (1.0f / 60.0f);
fRotationalAcceleration = Vector3.Zero;
}
float Yaw = MathHelper.ToRadians(fRotationalVelocity.Y * elapsed);
float Pitch = MathHelper.ToRadians(fRotationalVelocity.X * elapsed);
float Roll = MathHelper.ToRadians(fRotationalVelocity.Z * elapsed);
// create a rotation quaternion based on orientation changes - this is the amount to rotate
Quaternion Rotation = Quaternion.CreateFromYawPitchRoll(Yaw, Pitch, Roll);
// add the rotation to the current rotation quaternion
fOrientation *= Rotation;
UpdateOrientation();
// apply linear acceleration to velocity
fLinearVelocity += fLinearAcceleration * elapsed;
fLinearTime += elapsed;
while (fLinearTime >= (1.0f / 60.0f))
{
fLinearVelocity *= fLinearDrag;
fLinearTime -= (1.0f / 60.0f);
fLinearAcceleration = Vector3.Zero;
}
fLocalPosition.Add(fLinearVelocity);
Position = fLocalPosition + AttachedPosition;
// update matrices
UpdateWorldMatrix();
}
public void Update(Position3 planetPosition, Position3 cameraPosition, float fieldOfView)
{
Split(planetPosition, cameraPosition, fieldOfView);
}
public void LookAt(Position3 Target)
{
Target -= Position;
SetWorldMatrix(Matrix.CreateLookAt(Vector3.Zero, (Vector3)Target, (Vector3)fUp));
}
/// <summary>
/// Calculate the sphere-space position of the patch by determining where the center vertex lies on the sphere
/// </summary>
private void CalculatePatchPosition(TerrainNodeSplitItem item)
{
// find the cube position of the center vertex
double x = bounds.Left + bounds.Width / 2;
double y = bounds.Bottom + bounds.Height / 2;
// get the matrix used to rotate the a position to the appropriate cube face
Matrix faceMatrix = CubeFaces.GetFace(bounds.Face).FaceMatrix;
// create the vertex position in cube-space and rotate it to the appropriate face
Position3 cubePosition = new Position3(x, y, 1);
cubePosition.Transform(ref faceMatrix);
// get the vertex position on the unit sphere and rotate it to the appropriate face
Position3 spherePosition = Tools.CubeToSphereMapping(x, y, 1);
spherePosition.Transform(ref faceMatrix);
spherePosition.Normalize();
Vector2 patchPosition = new Vector2(Constants.PatchWidth / 2, Constants.PatchHeight / 2);
if (item == null)
{
// transform the vertex based on the user defined delegate - this returns the height value of the point on the sphere
createPosition(ref spherePosition, ref cubePosition, ref patchPosition, radius, out position);
}
else
{
double h = item.HeightData[(int)((patchPosition.Y + 1) * (Constants.PatchWidth + 2) + (patchPosition.X + 1))];
if (h < 0) h = 0;
position = spherePosition * (radius + h);
}
}
public TerrainNode FindNodeUnderPosition(Position3 position, out Vector3[] triangle, out double height, out Vector3 normal)
{
TerrainNode result = null;
result = front.FindNodeUnderPosition(position, out triangle, out height, out normal);
if (result == null)
result = back.FindNodeUnderPosition(position, out triangle, out height, out normal);
if (result == null)
result = left.FindNodeUnderPosition(position, out triangle, out height, out normal);
if (result == null)
result = right.FindNodeUnderPosition(position, out triangle, out height, out normal);
if (result == null)
result = top.FindNodeUnderPosition(position, out triangle, out height, out normal);
if (result == null)
result = bottom.FindNodeUnderPosition(position, out triangle, out height, out normal);
return result;
}
public void AddNormalize(ref Position3 V1, ref Vector3 V2)
{
X = V1.X + V2.X;
Y = V1.Y + V2.Y;
Z = V1.Z + V2.Z;
double L = 1 / Math.Sqrt(X * X + Y * Y + Z * Z);
X *= L;
Y *= L;
Z *= L;
}
private void CheckDistance(int x, int y, ref Vector3 v, ref float minDistance)
{
VertexPositionNormalTextureHeight p = vertexBuffer.Vertices[y * patchColumns + x]; // MapVertexIndex(x, y)];
float d = Vector3.DistanceSquared(p.Position, v);
if (d < minDistance)
{
minDistance = d;
closestPosition = new Position3(p.Position);
}
}
public bool Equals(Position3 P)
{
// if (P == null) return false;
return (X == P.X &&
Y == P.Y &&
Z == P.Z);
}
/// <summary>
/// Create a patch-space position by using the user supplied delegate.
/// </summary>
/// <param name="inPosition">Input position, located on the surface of a unit sphere</param>
/// <param name="outPosition">Output position, moved out to the sphere surface, or altered with noise, as determined by the user supplied delegate</param>
private void CreatePosition(ref Position3 spherePosition, ref Position3 cubePosition, ref Vector2 patchPosition, out Position3 outPosition, out double height)
{
height = createPosition(ref spherePosition, ref cubePosition, ref patchPosition, radius, out outPosition);
TranslateToPatchSpace(ref outPosition);
}
public void Add(ref Position3 V1, ref Position3 V2)
{
X = V1.X + V2.X;
Y = V1.Y + V2.Y;
Z = V1.Z + V2.Z;
}