// Affine transformation of vertex. Returns a new CSG.Vertex
public CSGVertex transform(CSGMatrix4x4 matrix4x4)
{
CSGVector3 newpos = this.pos.multiply4x4(matrix4x4);
CSGVector3 posPlusNormal = this.pos.plus(this.normal);
CSGVector3 newPosPlusNormal = posPlusNormal.multiply4x4(matrix4x4);
CSGVector3 newnormal = newPosPlusNormal.minus(newpos).unit();
return(new CSGVertex(newpos, newnormal));
}
// Construct a solid cylinder. Optional parameters are `start`, `end`,
// `radius`, and `slices`, which default to `[0, -1, 0]`, `[0, 1, 0]`, `1`, and
// `16`. The `slices` parameter controls the tessellation.
//
// Example usage:
//
// var cylinder = CSG.cylinder({
// start: [0, -1, 0],
// end: [0, 1, 0],
// radius: 1,
// slices: 16
// });
static public CSG cylinder(CSGVector3 s, CSGVector3 e, float radius, int slices, CSGShared shared)
{
CSGVector3 ray = e.minus(s);
CSGVector3 axisZ = ray.unit();
bool isY = (Math.Abs(axisZ.y) > 0.5f);
CSGVector3 axisX = new CSGVector3(isY ? 1 : 0, !isY ? 1 : 0, 0).cross(axisZ).unit();
CSGVector3 axisY = axisX.cross(axisZ).unit();
CSGVertex start = new CSGVertex(s, axisZ.negated());
CSGVertex end = new CSGVertex(e, axisZ.unit());
List <CSGPolygon> polygons = new List <CSGPolygon>();
for (float i = 0; i < slices; i++)
{
float t0 = i / slices;
float t1 = (i + 1) / slices;
//cylinderPoint(s, ray, radius, axisX, axisY, axisZ,
polygons.Add(
new CSGPolygon(
new CSGVertex[] {
start,
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 0, t0, -1),
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 0, t1, -1)
}, shared));
polygons.Add(
new CSGPolygon(
new CSGVertex[] {
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 0, t1, 0),
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 0, t0, 0),
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 1, t0, 0),
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 1, t1, 0)
}, shared));
polygons.Add(
new CSGPolygon(
new CSGVertex[] {
end,
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 1, t1, 1),
cylinderPoint(s, ray, radius, axisX, axisY, axisZ, 1, t0, 1)
}, shared));
}
return(CSG.fromPolygons(polygons));
}
public CSGVector3 lerp(CSGVector3 a, float t)
{
return(this.plus(a.minus(this).times(t)));
}
static public CSGPlane fromPoints(CSGVector3 a, CSGVector3 b, CSGVector3 c)
{
CSGVector3 n = b.minus(a).cross(c.minus(a)).unit();
return(new CSGPlane(n, n.dot(a)));
}