public static Mesh CreateSphere(float radius, int sliceCount, int stackCount)
{
Mesh mesh = new Mesh();
List<VertexDescription.PosNormVertex> vertices = new List<VertexDescription.PosNormVertex>();
List<int> indices = new List<int>();
//
// Compute the vertices stating at the top pole and moving down the stacks.
//
// Poles: note that there will be texture coordinate distortion as there is
// not a unique point on the texture map to assign to the pole when mapping
// a rectangular texture onto a sphere.
VertexDescription.PosNormVertex topVertex = Vertex(0.0f, +radius, 0.0f, 0.0f, +1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f);
VertexDescription.PosNormVertex bottomVertex = Vertex(0.0f, -radius, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f);
vertices.Add(topVertex);
float phiStep = MathUtil.Pi/stackCount;
float thetaStep = MathUtil.TwoPi/sliceCount;
// Compute vertices for each stack ring (do not count the poles as rings).
for(int i = 1; i <= stackCount-1; ++i)
{
float phi = i*phiStep;
// Vertices of ring.
for(int j = 0; j <= sliceCount; ++j)
{
float theta = j*thetaStep;
VertexDescription.PosNormVertex v;
// spherical to cartesian
v.Position.X = (float)(radius * Math.Sin(phi) * Math.Cos(theta));
v.Position.Y = (float)(radius * Math.Cos(phi));
v.Position.Z = (float)(radius * Math.Sin(phi) * Math.Sin(theta));
// Partial derivative of P with respect to theta
v.Tangent.X = (float)(-radius * Math.Sin(phi) * Math.Sin(theta));
v.Tangent.Y = 0.0f;
v.Tangent.Z = (float)(+radius * Math.Sin(phi) * Math.Cos(theta));
v.Tangent.Normalize();
v.Normal = Vector3.Normalize(v.Position);
v.TextCoord.X = theta / MathUtil.TwoPi;
v.TextCoord.Y = phi / MathUtil.Pi;
vertices.Add(v);
}
}
vertices.Add(bottomVertex);
//
// Compute indices for top stack. The top stack was written first to the vertex buffer
// and connects the top pole to the first ring.
//
for(int i = 1; i <= sliceCount; ++i)
{
indices.Add(0);
indices.Add(i+1);
indices.Add(i);
}
//
// Compute indices for inner stacks (not connected to poles).
//
// Offset the indices to the index of the first vertex in the first ring.
// This is just skipping the top pole vertex.
int baseIndex = 1;
int ringVertexCount = sliceCount+1;
for(int i = 0; i < stackCount-2; ++i)
{
for(int j = 0; j < sliceCount; ++j)
{
indices.Add(baseIndex + i * ringVertexCount + j);
indices.Add(baseIndex + i * ringVertexCount + j + 1);
indices.Add(baseIndex + (i + 1) * ringVertexCount + j);
indices.Add(baseIndex + (i + 1) * ringVertexCount + j);
indices.Add(baseIndex + i * ringVertexCount + j + 1);
indices.Add(baseIndex + (i + 1) * ringVertexCount + j + 1);
}
}
//
// Compute indices for bottom stack. The bottom stack was written last to the vertex buffer
// and connects the bottom pole to the bottom ring.
//
// South pole vertex was added last.
int southPoleIndex = vertices.Count-1;
// Offset the indices to the index of the first vertex in the last ring.
baseIndex = southPoleIndex - ringVertexCount;
for(int i = 0; i < sliceCount; ++i)
{
indices.Add(southPoleIndex);
indices.Add(baseIndex + i);
indices.Add(baseIndex + i + 1);
}
mesh.VertexCount = vertices.Count;
mesh.IndexCount = indices.Count;
mesh.VertexBuffer = SharpDX.Direct3D11.Buffer.Create(GraphicManager.Device, BindFlags.VertexBuffer, vertices.ToArray());
mesh.IndexBuffer = SharpDX.Direct3D11.Buffer.Create(GraphicManager.Device, BindFlags.IndexBuffer, indices.ToArray());
return mesh;
}
public static Mesh CreateCube(float width, float height, float depth)
{
Mesh mesh = new Mesh();
float w2 = 0.5f*width;
float h2 = 0.5f*height;
float d2 = 0.5f*depth;
mesh.VertexCount = 24;
mesh.IndexCount = 36;
VertexDescription.PosNormVertex[] v = new VertexDescription.PosNormVertex[24];
// Fill in the front face vertex data.
v[0] = Vertex(-w2, -h2, -d2, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f);
v[1] = Vertex(-w2, +h2, -d2, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f);
v[2] = Vertex(+w2, +h2, -d2, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f);
v[3] = Vertex(+w2, -h2, -d2, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f);
// Fill in the back face vertex data.
v[4] = Vertex(-w2, -h2, +d2, 0.0f, 0.0f, 1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f);
v[5] = Vertex(+w2, -h2, +d2, 0.0f, 0.0f, 1.0f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f);
v[6] = Vertex(+w2, +h2, +d2, 0.0f, 0.0f, 1.0f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f);
v[7] = Vertex(-w2, +h2, +d2, 0.0f, 0.0f, 1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f);
// Fill in the top face vertex data.
v[8] = Vertex(-w2, +h2, -d2, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f);
v[9] = Vertex(-w2, +h2, +d2, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f);
v[10] = Vertex(+w2, +h2, +d2, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f);
v[11] = Vertex(+w2, +h2, -d2, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f);
// Fill in the bottom face vertex data.
v[12] = Vertex(-w2, -h2, -d2, 0.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f);
v[13] = Vertex(+w2, -h2, -d2, 0.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f);
v[14] = Vertex(+w2, -h2, +d2, 0.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f);
v[15] = Vertex(-w2, -h2, +d2, 0.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f);
// Fill in the left face vertex data.
v[16] = Vertex(-w2, -h2, +d2, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f);
v[17] = Vertex(-w2, +h2, +d2, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f);
v[18] = Vertex(-w2, +h2, -d2, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f);
v[19] = Vertex(-w2, -h2, -d2, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f);
// Fill in the right face vertex data.
v[20] = Vertex(+w2, -h2, -d2, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f);
v[21] = Vertex(+w2, +h2, -d2, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f);
v[22] = Vertex(+w2, +h2, +d2, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f);
v[23] = Vertex(+w2, -h2, +d2, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f);
int[] i = new int[36];
// Fill in the front face index data
i[0] = 0; i[1] = 1; i[2] = 2;
i[3] = 0; i[4] = 2; i[5] = 3;
// Fill in the back face index data
i[6] = 4; i[7] = 5; i[8] = 6;
i[9] = 4; i[10] = 6; i[11] = 7;
// Fill in the top face index data
i[12] = 8; i[13] = 9; i[14] = 10;
i[15] = 8; i[16] = 10; i[17] = 11;
// Fill in the bottom face index data
i[18] = 12; i[19] = 13; i[20] = 14;
i[21] = 12; i[22] = 14; i[23] = 15;
// Fill in the left face index data
i[24] = 16; i[25] = 17; i[26] = 18;
i[27] = 16; i[28] = 18; i[29] = 19;
// Fill in the right face index data
i[30] = 20; i[31] = 21; i[32] = 22;
i[33] = 20; i[34] = 22; i[35] = 23;
mesh.VertexBuffer = SharpDX.Direct3D11.Buffer.Create(GraphicManager.Device, BindFlags.VertexBuffer, v);
mesh.IndexBuffer = SharpDX.Direct3D11.Buffer.Create(GraphicManager.Device, BindFlags.IndexBuffer, i);
return mesh;
}
