/// <summary>
/// Constructs a pyramid draft
/// </summary>
public static MeshDraft Pyramid(float radius, int segments, float height, bool generateUV = true)
{
float segmentAngle = 360f / segments;
float currentAngle = 0;
var ring = new Vector3[segments];
for (var i = 0; i < segments; i++)
{
ring[i] = Geometry.PointOnCircle3XZ(radius, currentAngle);
currentAngle += segmentAngle;
}
var draft = new MeshDraft().AddBaselessPyramid(Vector3.up * height, ring, generateUV);
if (generateUV)
{
var fanUV = new Vector2[segments];
currentAngle = 0;
for (var i = 0; i < segments; i++)
{
Vector2 uv = Geometry.PointOnCircle2(0.5f, currentAngle) + new Vector2(0.5f, 0.5f);
uv.x = 1 - uv.x;
fanUV[i] = uv;
currentAngle += segmentAngle;
}
draft.AddTriangleFan(ring, Vector3.down, fanUV, true);
}
else
{
draft.AddTriangleFan(ring, Vector3.down, true);
}
draft.name = "Pyramid";
return(draft);
}
/// <summary>
/// Constructs a cylinder draft
/// </summary>
public static MeshDraft Cylinder(float radius, int segments, float height, bool generateUV = true)
{
float segmentAngle = 360f / segments;
float currentAngle = 0;
Vector3 halfHeightUp = Vector3.up * height / 2;
var draft = new MeshDraft {
name = "Cylinder"
};
var lowerRing = new List <Vector3>(segments);
var lowerDiskUV = new List <Vector2>();
var upperRing = new List <Vector3>(segments);
var upperDiskUV = new List <Vector2>();
var strip = new List <Vector3>();
var stripNormals = new List <Vector3>();
var stripUV = new List <Vector2>();
for (var i = 0; i < segments; i++)
{
Vector3 lowerVertex;
Vector3 upperVertex;
AddCylinderPoints(radius, currentAngle, halfHeightUp, generateUV,
ref strip, ref stripUV, ref stripNormals, out lowerVertex, out upperVertex);
lowerRing.Add(lowerVertex);
upperRing.Add(upperVertex);
if (generateUV)
{
Vector2 uv = Geometry.PointOnCircle2(0.5f, currentAngle) + new Vector2(0.5f, 0.5f);
upperDiskUV.Add(uv);
uv.x = 1 - uv.x;
lowerDiskUV.Add(uv);
}
currentAngle += segmentAngle;
}
Vector3 lowerSeamVertex;
Vector3 upperSeamVertex;
AddCylinderPoints(radius, currentAngle, halfHeightUp, generateUV,
ref strip, ref stripUV, ref stripNormals, out lowerSeamVertex, out upperSeamVertex);
if (generateUV)
{
draft.AddTriangleFan(lowerRing, Vector3.down, lowerDiskUV, true);
draft.AddTriangleFan(upperRing, Vector3.up, upperDiskUV);
draft.AddTriangleStrip(strip, stripNormals, stripUV);
}
else
{
draft.AddTriangleFan(lowerRing, Vector3.down, true);
draft.AddTriangleFan(upperRing, Vector3.up);
draft.AddTriangleStrip(strip, stripNormals);
}
return(draft);
}
public static MeshDraft Cylinder(float radius, int segments, float heignt)
{
float segmentAngle = 360f / segments;
float currentAngle = 0;
var lowerRing = new List <Vector3>(segments);
var upperRing = new List <Vector3>(segments);
for (var i = 0; i < segments; i++)
{
var point = PTUtils.PointOnCircle3XZ(radius, currentAngle);
lowerRing.Add(point - Vector3.up * heignt / 2);
upperRing.Add(point + Vector3.up * heignt / 2);
currentAngle -= segmentAngle;
}
var draft = new MeshDraft {
name = "Cylinder"
}
.AddTriangleFan(lowerRing)
.Add(Band(lowerRing, upperRing));
upperRing.Reverse();
draft.AddTriangleFan(upperRing);
return(draft);
}
/// <summary>
/// Constructs a prism draft
/// </summary>
public static MeshDraft Prism(float radius, int segments, float height, bool generateUV = true)
{
float segmentAngle = 360f / segments;
float currentAngle = 0;
Vector3 halfHeightUp = Vector3.up * height / 2;
var lowerRing = new List <Vector3>(segments);
var lowerDiskUV = new List <Vector2>();
var upperRing = new List <Vector3>(segments);
var upperDiskUV = new List <Vector2>();
for (var i = 0; i < segments; i++)
{
var point = Geometry.PointOnCircle3XZ(radius, currentAngle);
lowerRing.Add(point - halfHeightUp);
upperRing.Add(point + halfHeightUp);
if (generateUV)
{
Vector2 uv = Geometry.PointOnCircle2(0.5f, currentAngle) + new Vector2(0.5f, 0.5f);
upperDiskUV.Add(uv);
uv.x = 1 - uv.x;
lowerDiskUV.Add(uv);
}
currentAngle += segmentAngle;
}
var draft = new MeshDraft {
name = "Prism"
}
.AddFlatQuadBand(lowerRing, upperRing, generateUV);
if (generateUV)
{
draft.AddTriangleFan(upperRing, Vector3.up, upperDiskUV)
.AddTriangleFan(lowerRing, Vector3.down, lowerDiskUV, true);
}
else
{
draft.AddTriangleFan(upperRing, Vector3.up)
.AddTriangleFan(lowerRing, Vector3.down, true);
}
return(draft);
}
/// <remarks>
/// https://en.wikipedia.org/wiki/Triangle_fan
/// </remarks>
public static MeshDraft TriangleFan(List <Vector3> fan, Vector3 normal)
{
var draft = new MeshDraft
{
name = "TriangleFan",
uv = new List <Vector2>(fan.Count),
};
draft.AddTriangleFan(fan, normal);
for (int i = 0; i < fan.Count; i++)
{
draft.uv.Add(new Vector2((float)i / fan.Count, (float)i / fan.Count));
}
return(draft);
}
public static MeshDraft Dodecahedron(float radius)
{
const float magicAngle1 = 52.62263590f;
const float magicAngle2 = 10.81231754f;
const float segmentAngle = 72;
float currentAngle = 0;
var lowerCap = new List <Vector3>();
var lowerRing = new List <Vector3>();
for (var i = 0; i < 5; i++)
{
lowerCap.Add(PTUtils.PointOnSphere(radius, currentAngle, -magicAngle1));
lowerRing.Add(PTUtils.PointOnSphere(radius, currentAngle, -magicAngle2));
currentAngle -= segmentAngle;
}
currentAngle = -segmentAngle / 2;
var upperCap = new List <Vector3>();
var upperRing = new List <Vector3>();
for (var i = 0; i < 5; i++)
{
upperCap.Add(PTUtils.PointOnSphere(radius, currentAngle, magicAngle1));
upperRing.Add(PTUtils.PointOnSphere(radius, currentAngle, magicAngle2));
currentAngle -= segmentAngle;
}
var draft = new MeshDraft {
name = "Dodecahedron"
}
.AddTriangleFan(lowerCap)
.Add(FlatBand(lowerCap, lowerRing))
.Add(FlatBand(lowerRing, upperRing))
.Add(FlatBand(upperRing, upperCap));
upperCap.Reverse();
draft.AddTriangleFan(upperCap);
return(draft);
}