protected override DX11IndexedGeometry GetGeom(DX11RenderContext context, int slice)
{
Sphere sphere = new Sphere();
sphere.CyclesX = this.FCyclesX[slice];
sphere.CyclesY = this.FCyclesY[slice];
sphere.Radius = this.FSize[slice];
sphere.ResX = this.FResX[slice];
sphere.ResY = this.FResY[slice];
return context.Primitives.Sphere(sphere);
}
public DX11IndexedGeometry Sphere(Sphere settings)
{
float radius = settings.Radius;
int resX = settings.ResX;
int resY = settings.ResY;
float cx = settings.CyclesX;
float cy = settings.CyclesY;
List<Pos4Norm3Tex2Vertex> vertices = new List<Pos4Norm3Tex2Vertex>();
List<int> indices = new List<int>();
float pi = (float)Math.PI;
float pidiv2 = pi * 0.5f;
float twopi = pi * 2.0f;
for (int i = 0; i <= resY; i++)
{
float v = 1 - (float)i / resY;
float latitude = (i * pi / resY) - pidiv2;
float dy = (float)Math.Sin(latitude * cy);
float dxz = (float)Math.Cos(latitude * cy);
// Create a single ring of vertices at this latitude.
for (int j = 0; j <= resX; j++)
{
float u = (float)j / resX;
float longitude = j * twopi / resX;
float dx = (float)Math.Sin(longitude * cx);
float dz = (float)Math.Cos(longitude * cx);
dx *= dxz;
dz *= dxz;
Pos4Norm3Tex2Vertex vertex = new Pos4Norm3Tex2Vertex();
vertex.Position = new Vector4(dx * radius, dy * radius, dz * radius, 1.0f);
vertex.Normals = Vector3.Normalize(new Vector3(vertex.Position.X, vertex.Position.Y, vertex.Position.Z));
vertex.TexCoords = new Vector2(1.0f-u,v);
vertices.Add(vertex);
}
}
int stride = resX + 1;
for (int i = 0; i < resY; i++)
{
for (int j = 0; j <= resX; j++)
{
int nextI = i + 1;
int nextJ = (j + 1) % stride;
indices.Add(i * stride + j);
indices.Add(i * stride + nextJ);
indices.Add(nextI * stride + j);
indices.Add(i * stride + nextJ);
indices.Add(nextI * stride + nextJ);
indices.Add(nextI * stride + j);
}
}
DX11IndexedGeometry geom = DX11IndexedGeometry.CreateFrom<Pos4Norm3Tex2Vertex>(context, vertices.ToArray(), indices.ToArray(), Pos4Norm3Tex2Vertex.Layout);
geom.HasBoundingBox = true;
geom.BoundingBox = new BoundingBox(new Vector3(-radius), new Vector3(radius));
geom.Tag = settings;
geom.PrimitiveType = settings.PrimitiveType;
return geom;
}
