private void SetBuffers(GraphicsDevice device, VertexMultitextured[] vertices, int[] indices)
{
VertexDeclaration vertexDeclaration = new VertexDeclaration(VertexMultitextured.VertexElements);
terrainVertexBuffer = new VertexBuffer(device, vertexDeclaration, vertices.Length, BufferUsage.WriteOnly);
terrainVertexBuffer.SetData(vertices.ToArray());
terrainIndexBuffer = new IndexBuffer(device, typeof(int), indices.Length, BufferUsage.WriteOnly);
terrainIndexBuffer.SetData(indices);
}
private VertexMultitextured[] SetVertices()
{
VertexMultitextured[] Vertices = new VertexMultitextured[width * length];
for (int x = 0; x < width; x++) {
for (int y = 0; y < length; y++) {
float x0, y0, z0, w0, p0;
Vertices[x + y * width].Position = new Vector3(x, Altitudes[x, y], -y);
Vertices[x + y * width].TextureCoordinate.X = (float)x / maxAlt;
Vertices[x + y * width].TextureCoordinate.Y = (float)y / maxAlt;
p0 = Altitudes[x, y] / maxAlt;
x0 = MathHelper.Clamp(1.0f - Math.Abs(p0 - 0.0f) * 6, 0, 1);
y0 = MathHelper.Clamp(1.0f - Math.Abs(p0 - 0.33f) * 5, 0, 1);
z0 = MathHelper.Clamp(1.0f - Math.Abs(p0 - 0.67f) * 5, 0, 1);
w0 = MathHelper.Clamp(1.0f - Math.Abs(p0 - 1.0f) * 5, 0, 1);
float isum = 1 / (x0 + y0 + z0 + w0);
Vertices[x + y * width].TexWeights.X = x0 * isum;
Vertices[x + y * width].TexWeights.Y = y0 * isum;
Vertices[x + y * width].TexWeights.Z = z0 * isum;
Vertices[x + y * width].TexWeights.W = w0 * isum;
}
}
return Vertices;
}
private VertexMultitextured[] CalculateNormals(VertexMultitextured[] vertices, int[] indices)
{
for (int i = 0; i < vertices.Length; i++) {
vertices[i].Normal = new Vector3(0, 0, 0);
}
for (int i = 0; i < indices.Length / 3; i++) {
int index1 = indices[i * 3];
int index2 = indices[i * 3 + 1];
int index3 = indices[i * 3 + 2];
Vector3 side1 = vertices[index1].Position - vertices[index3].Position;
Vector3 side2 = vertices[index1].Position - vertices[index2].Position;
Vector3 normal = Vector3.Cross(side1, side2);
vertices[index1].Normal += normal;
vertices[index2].Normal += normal;
vertices[index3].Normal += normal;
}
for (int i = 0; i < vertices.Length; i++) {
vertices[i].Normal.Normalize();
}
return vertices;
}
