/// <summary>
/// Create a mesh for a RoundLine.
/// </summary>
/// <remarks>
/// The RoundLine mesh has 3 sections:
/// 1. Two quads, from 0 to 1 (left to right)
/// 2. A half-disc, off the left side of the quad
/// 3. A half-disc, off the right side of the quad
///
/// The X and Y coordinates of the "normal" encode the rho and theta of each vertex
/// The "texture" encodes whether to scale and translate the vertex horizontally by length and radius
/// </remarks>
private void CreateRoundLineMesh()
{
const int primsPerCap = 6; // A higher primsPerCap produces rounder endcaps at the cost of more vertices
const int verticesPerCap = primsPerCap * 2 + 2;
const int primsPerCore = 4;
const int verticesPerCore = 8;
numVertices = (verticesPerCore + verticesPerCap + verticesPerCap) * LinesPerBatch;
numPrimitivesPerInstance = primsPerCore + primsPerCap + primsPerCap;
numPrimitives = numPrimitivesPerInstance * LinesPerBatch;
numIndices = 3 * numPrimitives;
short[] indices = new short[numIndices];
RoundLineVertex[] tri = new RoundLineVertex[numVertices];
int iv = 0;
int ii = 0;
int iVertex;
int iIndex;
for (int instance = 0; instance < LinesPerBatch; instance++)
{
// core vertices
const float pi2 = MathHelper.PiOver2;
const float threePi2 = 3 * pi2;
iVertex = iv;
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, -1.0f, 0), new Vector2(1, threePi2), new Vector2(0, 0), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, -1.0f, 0), new Vector2(1, threePi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, threePi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, threePi2), new Vector2(0, 0), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, pi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, pi2), new Vector2(0, 0), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 1.0f, 0), new Vector2(1, pi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 1.0f, 0), new Vector2(1, pi2), new Vector2(0, 0), instance);
// core indices
indices[ii++] = (short)(iVertex + 0);
indices[ii++] = (short)(iVertex + 1);
indices[ii++] = (short)(iVertex + 2);
indices[ii++] = (short)(iVertex + 2);
indices[ii++] = (short)(iVertex + 3);
indices[ii++] = (short)(iVertex + 0);
indices[ii++] = (short)(iVertex + 4);
indices[ii++] = (short)(iVertex + 6);
indices[ii++] = (short)(iVertex + 5);
indices[ii++] = (short)(iVertex + 6);
indices[ii++] = (short)(iVertex + 7);
indices[ii++] = (short)(iVertex + 5);
// left halfdisc
iVertex = iv;
iIndex = ii;
for (int i = 0; i < primsPerCap + 1; i++)
{
float deltaTheta = MathHelper.Pi / primsPerCap;
float theta0 = MathHelper.PiOver2 + i * deltaTheta;
float theta1 = theta0 + deltaTheta / 2;
// even-numbered indices are at the center of the halfdisc
tri[iVertex + 0] = new RoundLineVertex(new Vector3(0, 0, 0), new Vector2(0, theta1), new Vector2(0, 0), instance);
// odd-numbered indices are at the perimeter of the halfdisc
float x = (float)Math.Cos(theta0);
float y = (float)Math.Sin(theta0);
tri[iVertex + 1] = new RoundLineVertex(new Vector3(x, y, 0), new Vector2(1, theta0), new Vector2(1, 0), instance);
if (i < primsPerCap)
{
// indices follow this pattern: (0, 1, 3), (2, 3, 5), (4, 5, 7), ...
indices[iIndex + 0] = (short)(iVertex + 0);
indices[iIndex + 1] = (short)(iVertex + 1);
indices[iIndex + 2] = (short)(iVertex + 3);
iIndex += 3;
ii += 3;
}
iVertex += 2;
iv += 2;
}
// right halfdisc
for (int i = 0; i < primsPerCap + 1; i++)
{
float deltaTheta = MathHelper.Pi / primsPerCap;
float theta0 = 3 * MathHelper.PiOver2 + i * deltaTheta;
float theta1 = theta0 + deltaTheta / 2;
float theta2 = theta0 + deltaTheta;
// even-numbered indices are at the center of the halfdisc
tri[iVertex + 0] = new RoundLineVertex(new Vector3(0, 0, 0), new Vector2(0, theta1), new Vector2(0, 1), instance);
// odd-numbered indices are at the perimeter of the halfdisc
float x = (float)Math.Cos(theta0);
float y = (float)Math.Sin(theta0);
tri[iVertex + 1] = new RoundLineVertex(new Vector3(x, y, 0), new Vector2(1, theta0), new Vector2(1, 1), instance);
if (i < primsPerCap)
{
// indices follow this pattern: (0, 1, 3), (2, 3, 5), (4, 5, 7), ...
indices[iIndex + 0] = (short)(iVertex + 0);
indices[iIndex + 1] = (short)(iVertex + 1);
indices[iIndex + 2] = (short)(iVertex + 3);
iIndex += 3;
ii += 3;
}
iVertex += 2;
iv += 2;
}
}
vb = new VertexBuffer(device, RoundLineVertex.VertexDeclaration, numVertices, BufferUsage.WriteOnly);
vb.SetData(tri);
ib = new IndexBuffer(device, IndexElementSize.SixteenBits, numIndices, BufferUsage.WriteOnly);
ib.SetData(indices);
}
/// <summary>
/// Create a mesh for a RoundLine.
/// </summary>
/// <remarks>
/// The RoundLine mesh has 3 sections:
/// 1. Two quads, from 0 to 1 (left to right)
/// 2. A half-disc, off the left side of the quad
/// 3. A half-disc, off the right side of the quad
///
/// The X and Y coordinates of the "normal" encode the rho and theta of each vertex
/// The "texture" encodes whether to scale and translate the vertex horizontally by length and radius
/// </remarks>
private void CreateRoundLineMesh()
{
const int primsPerCap = 6; // A higher primsPerCap produces rounder endcaps at the cost of more vertices
const int verticesPerCap = primsPerCap * 2 + 2;
const int primsPerCore = 4;
const int verticesPerCore = 8;
numVertices = (verticesPerCore + verticesPerCap + verticesPerCap) * LinesPerBatch;
numPrimitivesPerInstance = primsPerCore + primsPerCap + primsPerCap;
numPrimitives = numPrimitivesPerInstance * LinesPerBatch;
numIndices = 3 * numPrimitives;
short[] indices = new short[numIndices];
RoundLineVertex[] tri = new RoundLineVertex[numVertices];
int iv = 0;
int ii = 0;
int iVertex;
int iIndex;
for (int instance = 0; instance < LinesPerBatch; instance++)
{
// core vertices
const float pi2 = MathHelper.PiOver2;
const float threePi2 = 3 * pi2;
iVertex = iv;
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, -1.0f, 0), new Vector2(1, threePi2), new Vector2(0, 0), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, -1.0f, 0), new Vector2(1, threePi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, threePi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, threePi2), new Vector2(0, 0), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, pi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 0.0f, 0), new Vector2(0, pi2), new Vector2(0, 0), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 1.0f, 0), new Vector2(1, pi2), new Vector2(0, 1), instance);
tri[iv++] = new RoundLineVertex(new Vector3(0.0f, 1.0f, 0), new Vector2(1, pi2), new Vector2(0, 0), instance);
// core indices
indices[ii++] = (short)(iVertex + 0);
indices[ii++] = (short)(iVertex + 1);
indices[ii++] = (short)(iVertex + 2);
indices[ii++] = (short)(iVertex + 2);
indices[ii++] = (short)(iVertex + 3);
indices[ii++] = (short)(iVertex + 0);
indices[ii++] = (short)(iVertex + 4);
indices[ii++] = (short)(iVertex + 6);
indices[ii++] = (short)(iVertex + 5);
indices[ii++] = (short)(iVertex + 6);
indices[ii++] = (short)(iVertex + 7);
indices[ii++] = (short)(iVertex + 5);
// left halfdisc
iVertex = iv;
iIndex = ii;
for (int i = 0; i < primsPerCap + 1; i++)
{
float deltaTheta = MathHelper.Pi / primsPerCap;
float theta0 = MathHelper.PiOver2 + i * deltaTheta;
float theta1 = theta0 + deltaTheta / 2;
// even-numbered indices are at the center of the halfdisc
tri[iVertex + 0] = new RoundLineVertex(new Vector3(0, 0, 0), new Vector2(0, theta1), new Vector2(0, 0), instance);
// odd-numbered indices are at the perimeter of the halfdisc
float x = (float)Math.Cos(theta0);
float y = (float)Math.Sin(theta0);
tri[iVertex + 1] = new RoundLineVertex(new Vector3(x, y, 0), new Vector2(1, theta0), new Vector2(1, 0), instance);
if (i < primsPerCap)
{
// indices follow this pattern: (0, 1, 3), (2, 3, 5), (4, 5, 7), ...
indices[iIndex + 0] = (short)(iVertex + 0);
indices[iIndex + 1] = (short)(iVertex + 1);
indices[iIndex + 2] = (short)(iVertex + 3);
iIndex += 3;
ii += 3;
}
iVertex += 2;
iv += 2;
}
// right halfdisc
for (int i = 0; i < primsPerCap + 1; i++)
{
float deltaTheta = MathHelper.Pi / primsPerCap;
float theta0 = 3 * MathHelper.PiOver2 + i * deltaTheta;
float theta1 = theta0 + deltaTheta / 2;
float theta2 = theta0 + deltaTheta;
// even-numbered indices are at the center of the halfdisc
tri[iVertex + 0] = new RoundLineVertex(new Vector3(0, 0, 0), new Vector2(0, theta1), new Vector2(0, 1), instance);
// odd-numbered indices are at the perimeter of the halfdisc
float x = (float)Math.Cos(theta0);
float y = (float)Math.Sin(theta0);
tri[iVertex + 1] = new RoundLineVertex(new Vector3(x, y, 0), new Vector2(1, theta0), new Vector2(1, 1), instance);
if (i < primsPerCap)
{
// indices follow this pattern: (0, 1, 3), (2, 3, 5), (4, 5, 7), ...
indices[iIndex + 0] = (short)(iVertex + 0);
indices[iIndex + 1] = (short)(iVertex + 1);
indices[iIndex + 2] = (short)(iVertex + 3);
iIndex += 3;
ii += 3;
}
iVertex += 2;
iv += 2;
}
}
vb = new VertexBuffer(device, RoundLineVertex.VertexDeclaration, numVertices, BufferUsage.WriteOnly);
vb.SetData(tri);
ib = new IndexBuffer(device, IndexElementSize.SixteenBits, numIndices, BufferUsage.WriteOnly);
ib.SetData(indices);
}