public void MergeLeft(Heightmap leftTile, int transitionWidth)
{
if (leftTile == null)
{
throw new ArgumentNullException("leftTile");
}
if (leftTile.Width != Width || leftTile.Depth != Depth)
{
throw new ArgumentException("Tiles must have equal widths and depths", "leftTile");
}
if (transitionWidth >= Width)
{
throw new ArgumentException("Transition width must be less than tile width", "transitionWidth");
}
for (int x = 0; x < transitionWidth; x++)
{
for (int z = 0; z < Depth; z++)
{
float leftEdgeHeight = leftTile.GetHeightValue(leftTile.Width - 1, z);
float originalHeight = GetHeightValue(x, z);
float newHeight = MathHelper.Lerp(leftEdgeHeight, originalHeight, (float)x / (transitionWidth - 1));
SetHeightValue(x, z, newHeight);
}
}
}
/// <summary>
/// Clone the heightmap.
/// </summary>
/// <returns></returns>
public object Clone()
{
var heightmap = new Heightmap(_width, _depth, _minimumHeight, _maximumHeight,
(float[])_heightValues.Clone(), _randomSeed);
return(heightmap);
}
/// <summary>
/// Default constructor
/// </summary>
/// <param name="game"></param>
/// <param name="cameraProvider"></param>
/// <param name="heightmap"></param>
/// <param name="world"></param>
public TerrainMesh(Game game, ICameraProvider cameraProvider, Heightmap heightmap, Matrix world)
: base(game)
{
Patches = new List<TerrainPatch>();
Heightmap = heightmap;
_cameraProvider = cameraProvider;
World = world;
}
// /// <summary>
// /// Build a terrain patch.
// /// </summary>
// /// <param name="game"></param>
// /// <param name="heightmap"></param>
// /// <param name="worldMatrix"></param>
// /// <param name="width"></param>
// /// <param name="depth"></param>
// /// <param name="offsetX"></param>
// /// <param name="offsetZ"></param>
// public static void BuildPatch(Game game, Heightmap heightmap, Matrix worldMatrix, int width, int depth, int offsetX, int offsetZ)
// {
//
// }
/// <summary>
/// Build the vertex buffer as well as the bounding box.
/// </summary>
/// <param name="heightmap"></param>
private void BuildVertexBuffer(Heightmap heightmap)
{
int index = 0;
_boundingBox.Min.Y = float.MaxValue;
_boundingBox.Max.Y = float.MinValue;
Geometry = new VertexPositionNormalTexture[Width * Depth];
for (int z = _offsetZ; z < _offsetZ + Depth; ++z)
{
for (int x = _offsetX; x < _offsetX + Width; ++x)
{
// We need to connect the patches by increasing each patch width and depth by 1,
// but this means the patches along some of the edges will run out of
// heightmap data, so make sure we cap the index at the edge
int cappedX = Math.Min(x, heightmap.Width - 1);
int cappedZ = Math.Min(z, heightmap.Depth - 1);
float height = heightmap.GetHeightValue(cappedX, cappedZ);
if (height < _boundingBox.Min.Y)
{
_boundingBox.Min.Y = height;
}
if (height > _boundingBox.Max.Y)
{
_boundingBox.Max.Y = height;
}
var position = new Vector3(x, height, z);
Vector3 normal;
ComputeVertexNormal(heightmap, cappedX, cappedZ, out normal);
Geometry[index] = new VertexPositionNormalTexture(position, normal, new Vector2(x, z));
++index;
}
}
}
/// <summary>
/// Add two heightmaps together.
/// </summary>
/// <param name="heightmap"></param>
public void AddHeightmap(Heightmap heightmap)
{
// Reject the heightmap if it doesn't fit.
if ((_width != heightmap.Width) ||
(_depth != heightmap.Depth) ||
(_minimumHeight != heightmap.MinimumHeight) ||
(_maximumHeight != heightmap.MaximumHeight))
{
return;
}
// Add the heightmaps together.
for (int x = 0; x < _width; ++x)
{
for (int z = 0; z < _depth; ++z)
{
_heightValues[x + z * _width] = _heightValues[x + z * _width] + heightmap.GetHeightValue(x, z);
}
}
}
/// <summary>
/// Combine the heightmap with the passed heightmap.
/// The amount variable is the ratio of the heightmap passed as a parameter.
/// </summary>
/// <param name="heightmap"></param>
/// <param name="amount"></param>
public void CombineHeightmap(Heightmap heightmap, float amount)
{
// Reject the heightmap if it doesn't fit.
if ((_width != heightmap.Width) ||
(_depth != heightmap.Depth) ||
(_minimumHeight != heightmap.MinimumHeight) ||
(_maximumHeight != heightmap.MaximumHeight))
{
return;
}
// Combine the heightmaps.
// H1 = H1 * (1.0f - amount) + H2 * amount
for (int x = 0; x < _width; ++x)
{
for (int z = 0; z < _depth; ++z)
{
_heightValues[x + z * _width] = _heightValues[x + z * _width] * (1.0f - amount) +
heightmap.GetHeightValue(x, z) * amount;
}
}
}
/// <summary>
/// Default constructor.
/// </summary>
public TerrainPatch(Game game, Heightmap heightmap, Matrix worldMatrix, int width, int depth, int offsetX,
int offsetZ)
{
_boundingBox = new BoundingBox();
_game = game;
Width = width;
Depth = depth;
_offsetX = offsetX;
_offsetZ = offsetZ;
_boundingBox.Min.X = offsetX;
_boundingBox.Min.Z = offsetZ;
_boundingBox.Max.X = offsetX + width;
_boundingBox.Max.Z = offsetZ + depth;
BuildVertexBuffer(heightmap);
_vertexBuffer = new VertexBuffer(_game.GraphicsDevice,
VertexPositionNormalTexture.SizeInBytes * Geometry.Length,
BufferUsage.WriteOnly);
_vertexBuffer.SetData(Geometry);
BuildIndexBuffer();
_indexBuffer = new IndexBuffer(_game.GraphicsDevice, sizeof(short) * _indices.Length,
BufferUsage.WriteOnly, IndexElementSize.SixteenBits);
_indexBuffer.SetData(_indices);
// Apply the world matrix transformation to the bounding box.
_boundingBox.Min = Vector3.Transform(_boundingBox.Min, worldMatrix);
_boundingBox.Max = Vector3.Transform(_boundingBox.Max, worldMatrix);
}
/// <summary>
/// Default constructor.
/// </summary>
public TerrainPatch(Game game, Heightmap heightmap, Matrix worldMatrix, int width, int depth, int offsetX,
int offsetZ)
{
_boundingBox = new BoundingBox();
_game = game;
Width = width;
Depth = depth;
_offsetX = offsetX;
_offsetZ = offsetZ;
_boundingBox.Min.X = offsetX;
_boundingBox.Min.Z = offsetZ;
_boundingBox.Max.X = offsetX + width;
_boundingBox.Max.Z = offsetZ + depth;
BuildVertexBuffer(heightmap);
_vertexBuffer = new VertexBuffer(_game.GraphicsDevice,
VertexPositionNormalTexture.SizeInBytes*Geometry.Length,
BufferUsage.WriteOnly);
_vertexBuffer.SetData(Geometry);
BuildIndexBuffer();
_indexBuffer = new IndexBuffer(_game.GraphicsDevice, sizeof (short)*_indices.Length,
BufferUsage.WriteOnly, IndexElementSize.SixteenBits);
_indexBuffer.SetData(_indices);
// Apply the world matrix transformation to the bounding box.
_boundingBox.Min = Vector3.Transform(_boundingBox.Min, worldMatrix);
_boundingBox.Max = Vector3.Transform(_boundingBox.Max, worldMatrix);
}
/// <summary>
/// Add two heightmaps together.
/// </summary>
/// <param name="heightmap"></param>
public void AddHeightmap(Heightmap heightmap)
{
// Reject the heightmap if it doesn't fit.
if ((_width != heightmap.Width) ||
(_depth != heightmap.Depth) ||
(_minimumHeight != heightmap.MinimumHeight) ||
(_maximumHeight != heightmap.MaximumHeight))
{
return;
}
// Add the heightmaps together.
for (int x = 0; x < _width; ++x)
{
for (int z = 0; z < _depth; ++z)
{
_heightValues[x + z*_width] = _heightValues[x + z*_width] + heightmap.GetHeightValue(x, z);
}
}
}
public void MergeLeft(Heightmap leftTile, int transitionWidth)
{
if (leftTile == null) throw new ArgumentNullException("leftTile");
if (leftTile.Width != Width || leftTile.Depth != Depth)
throw new ArgumentException("Tiles must have equal widths and depths", "leftTile");
if (transitionWidth >= Width)
throw new ArgumentException("Transition width must be less than tile width", "transitionWidth");
for (int x = 0; x < transitionWidth; x++)
{
for (int z = 0; z < Depth; z++)
{
float leftEdgeHeight = leftTile.GetHeightValue(leftTile.Width - 1, z);
float originalHeight = GetHeightValue(x, z);
float newHeight = MathHelper.Lerp(leftEdgeHeight, originalHeight, (float) x/(transitionWidth - 1));
SetHeightValue(x, z, newHeight);
}
}
}
/// <summary>
/// Returns a 2D array of [rows, cols].
/// </summary>
/// <param name="hm"></param>
/// <returns></returns>
private static float[,] HeightmapToValues(Heightmap hm)
{
var heightValues = new float[hm.Depth, hm.Width];
for (int i = 0; i < hm.HeightValues.Length; i++)
{
int col = i % hm.Depth;
int row = i / hm.Width;
heightValues[row, col] = hm.HeightValues[i];
}
return heightValues;
}
/// <summary>
/// Compute vertex normal at the given x,z coordinate.
/// </summary>
/// <param name="heightmap"></param>
/// <param name="x"></param>
/// <param name="z"></param>
/// <param name="normal"></param>
private static void ComputeVertexNormal(Heightmap heightmap, int x, int z, out Vector3 normal)
{
int width = heightmap.Width;
int depth = heightmap.Depth;
Vector3 p1;
Vector3 p2;
Vector3 avgNormal = Vector3.Zero;
int avgCount = 0;
bool spaceAbove = false;
bool spaceBelow = false;
bool spaceLeft = false;
bool spaceRight = false;
Vector3 tmpNormal;
Vector3 v1;
Vector3 v2;
var center = new Vector3(x, heightmap.GetHeightValue(x, z), z);
if (x > 0)
{
spaceLeft = true;
}
if (x < width - 1)
{
spaceRight = true;
}
if (z > 0)
{
spaceAbove = true;
}
if (z < depth - 1)
{
spaceBelow = true;
}
if (spaceAbove && spaceLeft)
{
p1 = new Vector3(x - 1, heightmap.GetHeightValue(x - 1, z), z);
p2 = new Vector3(x - 1, heightmap.GetHeightValue(x - 1, z - 1), z - 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
if (spaceAbove && spaceRight)
{
p1 = new Vector3(x, heightmap.GetHeightValue(x, z - 1), z - 1);
p2 = new Vector3(x + 1, heightmap.GetHeightValue(x + 1, z - 1), z - 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
if (spaceBelow && spaceRight)
{
p1 = new Vector3(x + 1, heightmap.GetHeightValue(x + 1, z), z);
p2 = new Vector3(x + 1, heightmap.GetHeightValue(x + 1, z + 1), z + 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
if (spaceBelow && spaceLeft)
{
p1 = new Vector3(x, heightmap.GetHeightValue(x, z + 1), z + 1);
p2 = new Vector3(x - 1, heightmap.GetHeightValue(x - 1, z + 1), z + 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
normal = avgNormal / avgCount;
}
// /// <summary>
// /// Build a terrain patch.
// /// </summary>
// /// <param name="game"></param>
// /// <param name="heightmap"></param>
// /// <param name="worldMatrix"></param>
// /// <param name="width"></param>
// /// <param name="depth"></param>
// /// <param name="offsetX"></param>
// /// <param name="offsetZ"></param>
// public static void BuildPatch(Game game, Heightmap heightmap, Matrix worldMatrix, int width, int depth, int offsetX, int offsetZ)
// {
//
// }
/// <summary>
/// Build the vertex buffer as well as the bounding box.
/// </summary>
/// <param name="heightmap"></param>
private void BuildVertexBuffer(Heightmap heightmap)
{
int index = 0;
_boundingBox.Min.Y = float.MaxValue;
_boundingBox.Max.Y = float.MinValue;
Geometry = new VertexPositionNormalTexture[Width*Depth];
for (int z = _offsetZ; z < _offsetZ + Depth; ++z)
{
for (int x = _offsetX; x < _offsetX + Width; ++x)
{
// We need to connect the patches by increasing each patch width and depth by 1,
// but this means the patches along some of the edges will run out of
// heightmap data, so make sure we cap the index at the edge
int cappedX = Math.Min(x, heightmap.Width - 1);
int cappedZ = Math.Min(z, heightmap.Depth - 1);
float height = heightmap.GetHeightValue(cappedX, cappedZ);
if (height < _boundingBox.Min.Y)
{
_boundingBox.Min.Y = height;
}
if (height > _boundingBox.Max.Y)
{
_boundingBox.Max.Y = height;
}
var position = new Vector3(x, height, z);
Vector3 normal;
ComputeVertexNormal(heightmap, cappedX, cappedZ, out normal);
Geometry[index] = new VertexPositionNormalTexture(position, normal, new Vector2(x, z));
++index;
}
}
}
public void BuildTerrain(int width, float minHeight, float maxHeight)
{
_width = width;
_minHeight = minHeight;
_maxHeight = maxHeight;
// When running test scenarios over and over we need to generate the exact same terrains
const int myRandomTerrainSeed = 1337;
Heightmap = new Heightmap(myRandomTerrainSeed);
Heightmap.GenerateFaultHeightmap(_width, _width, _minHeight, _maxHeight,
new HeightmapFaultSettings(16, 256, 1024, 128, 0.5f));
// TODO Adding world transformation confuses the sunlight/terrain shader.. not sure why
// const float scale = 10;
Matrix world = Matrix.Identity;
// Matrix.CreateScale(scale) * Matrix.CreateTranslation(scale * Position);
Mesh = new TerrainMesh(Game, _cameraProvider, Heightmap, world);
Mesh.Initialize();
// TerrainMeshes.Add(first);
return;
}
/// <summary>
/// Clone the heightmap.
/// </summary>
/// <returns></returns>
public object Clone()
{
var heightmap = new Heightmap(_width, _depth, _minimumHeight, _maximumHeight,
(float[]) _heightValues.Clone(), _randomSeed);
return heightmap;
}
/// <summary>
/// Combine the heightmap with the passed heightmap.
/// The amount variable is the ratio of the heightmap passed as a parameter.
/// </summary>
/// <param name="heightmap"></param>
/// <param name="amount"></param>
public void CombineHeightmap(Heightmap heightmap, float amount)
{
// Reject the heightmap if it doesn't fit.
if ((_width != heightmap.Width) ||
(_depth != heightmap.Depth) ||
(_minimumHeight != heightmap.MinimumHeight) ||
(_maximumHeight != heightmap.MaximumHeight))
{
return;
}
// Combine the heightmaps.
// H1 = H1 * (1.0f - amount) + H2 * amount
for (int x = 0; x < _width; ++x)
{
for (int z = 0; z < _depth; ++z)
{
_heightValues[x + z*_width] = _heightValues[x + z*_width]*(1.0f - amount) +
heightmap.GetHeightValue(x, z)*amount;
}
}
}
/// <summary>
/// Compute vertex normal at the given x,z coordinate.
/// </summary>
/// <param name="heightmap"></param>
/// <param name="x"></param>
/// <param name="z"></param>
/// <param name="normal"></param>
private static void ComputeVertexNormal(Heightmap heightmap, int x, int z, out Vector3 normal)
{
int width = heightmap.Width;
int depth = heightmap.Depth;
Vector3 p1;
Vector3 p2;
Vector3 avgNormal = Vector3.Zero;
int avgCount = 0;
bool spaceAbove = false;
bool spaceBelow = false;
bool spaceLeft = false;
bool spaceRight = false;
Vector3 tmpNormal;
Vector3 v1;
Vector3 v2;
var center = new Vector3(x, heightmap.GetHeightValue(x, z), z);
if (x > 0)
{
spaceLeft = true;
}
if (x < width - 1)
{
spaceRight = true;
}
if (z > 0)
{
spaceAbove = true;
}
if (z < depth - 1)
{
spaceBelow = true;
}
if (spaceAbove && spaceLeft)
{
p1 = new Vector3(x - 1, heightmap.GetHeightValue(x - 1, z), z);
p2 = new Vector3(x - 1, heightmap.GetHeightValue(x - 1, z - 1), z - 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
if (spaceAbove && spaceRight)
{
p1 = new Vector3(x, heightmap.GetHeightValue(x, z - 1), z - 1);
p2 = new Vector3(x + 1, heightmap.GetHeightValue(x + 1, z - 1), z - 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
if (spaceBelow && spaceRight)
{
p1 = new Vector3(x + 1, heightmap.GetHeightValue(x + 1, z), z);
p2 = new Vector3(x + 1, heightmap.GetHeightValue(x + 1, z + 1), z + 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
if (spaceBelow && spaceLeft)
{
p1 = new Vector3(x, heightmap.GetHeightValue(x, z + 1), z + 1);
p2 = new Vector3(x - 1, heightmap.GetHeightValue(x - 1, z + 1), z + 1);
v1 = p1 - center;
v2 = p2 - p1;
tmpNormal = Vector3.Cross(v1, v2);
avgNormal += tmpNormal;
++avgCount;
}
normal = avgNormal/avgCount;
}
