/// <inheritdoc />
public override List <int> GenerateIndexList(int resolutionU, int resolutionV, int indexOffset = 0)
{
// The index list of a model tells the GPU between which vertices to draw triangles. Each three consecutive
// indices constitute a single triangle. Since the Capsule vertex array consists of several lists stitched
// together, the indices of the shaft and endCap will have shifted by some amount. Therefore, calculate
// this index offset for all submodels:
int indexOffset2 = indexOffset + Hemisphere.CalculateVertexCount(resolutionU, resolutionU / 4) - resolutionU;
int indexOffset3 = indexOffset2 + Cylinder.CalculateVertexCount(resolutionU, resolutionV) - resolutionU;
int indexOffset4 = indexOffset3 + Hemisphere.CalculateVertexCount(resolutionU, resolutionU / 4) - resolutionU;
// Generate the startCap indices as normal:
List <int> startCapList = startCap.GenerateIndexList(resolutionU, resolutionU / 4, indexOffset);
// Generate a shaft, using the last ring of the startCap to begin with. This is done by subtracting
// `resolutionU` from indexOffset2. This automatically stitches the gap between the start cap and the shaft:
List <int> shaftList = shaft.GenerateIndexList(resolutionU, resolutionV - 1, indexOffset2);
// Generate the endCap indices as normal:
List <int> endCapList = endCap.GenerateIndexList(resolutionU, resolutionU / 4, indexOffset3);
// The final ring between the endCap and the shaft must be generated manually:
List <int> stitchList = new List <int>(resolutionU);
// Add a ring of triangles:
for (int i = 1; i < resolutionU - 1; i++)
{
int invertedI = resolutionU - i;
stitchList.Add(indexOffset + invertedI + indexOffset4);
stitchList.Add(indexOffset + (i + 1) + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + i + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + (invertedI - 1) + indexOffset4);
stitchList.Add(indexOffset + (i + 1) + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + invertedI + indexOffset4);
}
// Stitch the end of the ring of triangles:
stitchList.Add(indexOffset + 1 + indexOffset4);
stitchList.Add(indexOffset + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + resolutionU - 1 + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + indexOffset4);
stitchList.Add(indexOffset + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + 1 + indexOffset4);
stitchList.Add(indexOffset + resolutionU - 1 + indexOffset4);
stitchList.Add(indexOffset + 1 + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + indexOffset3 - resolutionU);
stitchList.Add(indexOffset + indexOffset4);
stitchList.Add(indexOffset + resolutionU - 1 + indexOffset4);
stitchList.Add(indexOffset + indexOffset3 - resolutionU);
return(startCapList.Concat(shaftList).Concat(endCapList).Concat(stitchList).ToList());
}
public override List <int> GenerateIndexList(int resolutionU, int resolutionV, int indexOffset = 0)
{
int indexOffset2 = indexOffset + Hemisphere.CalculateVertexCount(resolutionU, resolutionU / 4);
int indexOffset3 = indexOffset + indexOffset2 + Cylinder.CalculateVertexCount(resolutionU, resolutionV);
List <int> startCapList = startCap.GenerateIndexList(resolutionU, resolutionU / 4, indexOffset);
List <int> shaftList = shaft.GenerateIndexList(resolutionU, resolutionV, indexOffset2);
List <int> endCapList = endCap.GenerateIndexList(resolutionU, resolutionU / 4, indexOffset3);
return(startCapList.Concat(shaftList).Concat(endCapList).ToList());
}
/// <inheritdoc />
public override List <Vertex> GenerateVertexList(int resolutionU, int resolutionV)
{
// Generate the vertices of two end caps, and a shaft in between:
List <Vertex> startCapList = startCap.GenerateVertexList(resolutionU, resolutionU / 4);
List <Vertex> endCapList = endCap.GenerateVertexList(resolutionU, resolutionU / 4);
// Using a slice, remove the first and last ring of vertices of the shaft, which overlap with the last
// rings of the startCap and endCap respectively. Later we will stitch the shaft and end caps together with
// triangles between them, during the GenerateIndexList() step.
Slice <Vertex> shaftSlice = new Slice <Vertex>(
shaft.GenerateVertexList(resolutionU, resolutionV),
resolutionU,
Cylinder.CalculateVertexCount(resolutionU, resolutionV) - 2 * resolutionU);
// Recalculate the surface normal between the cylinder and the start cap:
for (int i = 0; i < (resolutionU - 1); i++)
{
dvec3 surfacePosition = startCapList[(resolutionU / 4 - 1) * resolutionU + i + 1].Position;
dvec3 du = surfacePosition - startCapList[(resolutionU / 4 - 1) * resolutionU + i + 1 + 1].Position;
dvec3 dv = surfacePosition - shaftSlice[i].Position;
// Calculate the position of the rings of vertices:
dvec3 surfaceNormal = dvec3.Cross(du.Normalized, dv.Normalized);
startCapList[(resolutionU / 4 - 1) * resolutionU + i + 1] = new Vertex((vec3)surfacePosition, (vec3)surfaceNormal);
}
// Stitch the end of the triangles:
dvec3 surfacePosition2 = startCapList[(resolutionU / 4 - 1) * resolutionU + resolutionU].Position;
dvec3 du2 = surfacePosition2 - startCapList[(resolutionU / 4 - 1) * resolutionU + 1].Position;
dvec3 dv2 = surfacePosition2 - shaftSlice[resolutionU].Position;
// Calculate the position of the rings of vertices:
dvec3 surfaceNormal2 = dvec3.Cross(du2.Normalized, dv2.Normalized);
startCapList[(resolutionU / 4 - 1) * resolutionU + resolutionU] = new Vertex((vec3)surfacePosition2, (vec3)surfaceNormal2);
return(startCapList.Concat(shaftSlice).Concat(endCapList).ToList());
}
