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reduced complexity of SCNGeometry.path function to help linter
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@maxxfrazer
maxxfrazer committed Dec 18, 2018
1 parent 4c8e0b9 commit f052924
Showing 1 changed file with 19 additions and 25 deletions.
44 changes: 19 additions & 25 deletions SCNPath/SCNGeometry+Extensions.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -87,7 +87,6 @@ public extension SCNGeometry {
if materials.isEmpty {
materials.append(SCNGeometry.defaultSCNPathMaterial)
}
let verts = path
if curveDistance < 1 {
os_log(.error, "curve distance is too low, minimum value is 1")
}
Expand All @@ -102,44 +101,41 @@ public extension SCNGeometry {
for (index, vert) in path.enumerated() {
if index == 0 {
// first point
directionV = SCNVector3(verts[index + 1].z - vert.z, 0, verts[index + 1].x - vert.x)
directionV = SCNVector3(path[index + 1].z - vert.z, 0, vert.x - path[index + 1].x)
} else if index < maxIndex {
let toThis = (vert - verts[index - 1]).flattened().normalized()
let fromThis = (verts[index + 1] - vert).flattened().normalized()
let toThis = (vert - path[index - 1]).flattened().normalized()
let fromThis = (path[index + 1] - vert).flattened().normalized()
angleBent = fromThis.angleChange(to: toThis)
let resultant = (toThis + fromThis) / 2
directionV = SCNVector3(resultant.z, 0, resultant.x)
directionV = SCNVector3(resultant.z, 0, -resultant.x)
} else {
// last point
directionV = SCNVector3(vert.z - verts[index - 1].z, 0, vert.x - verts[index - 1].x)
directionV = SCNVector3(vert.z - path[index - 1].z, 0, path[index - 1].x - vert.x)
}
let addToPoint = directionV.normalized() * (width / 2)
if curvePoints > 0, path.count >= index + 2, var bentBy = angleBent {
let curvePoints = curvePoints
let edge1 = SCNVector3(vert.x - addToPoint.x, vert.y, vert.z + addToPoint.z)
let edge2 = SCNVector3(vert.x + addToPoint.x, vert.y, vert.z - addToPoint.z)
var bendAround: SCNVector3!
let edge1 = vert - addToPoint
let edge2 = vert + addToPoint
var bendAround = vert - (addToPoint * curveDistance)

if newTurning(points: Array(verts[(index-1)...(index+1)])) < 0 { // left turn
bendAround = SCNVector3(vert.x + addToPoint.x * curveDistance, vert.y, vert.z - addToPoint.z * curveDistance)
if newTurning(points: Array(path[(index-1)...(index+1)])) < 0 { // left turn
bendAround = vert + (addToPoint * curveDistance)
bentBy *= -1
} else { // right turn
bendAround = SCNVector3(vert.x - addToPoint.x * curveDistance, vert.y, vert.z + addToPoint.z * curveDistance)
}
for val in 0...Int(curvePoints) {
vertices.append(
edge2.rotate(about: bendAround, by: (-0.5 + Float(val) / curvePoints) * bentBy)
)
vertices.append(
edge1.rotate(about: bendAround, by: (-0.5 + Float(val) / curvePoints) * bentBy)
)
vertices.append(edge2.rotate(
about: bendAround, by: (-0.5 + Float(val) / curvePoints) * bentBy))
vertices.append(edge1.rotate(
about: bendAround, by: (-0.5 + Float(val) / curvePoints) * bentBy))
addTriangleIndices(indices: &indices, at: UInt32(vertices.count - 2))
vertices.append(contentsOf: vertices[(vertices.count - 2)...])
}
} else {
vertices.append(SCNVector3(vert.x + addToPoint.x, vert.y, vert.z - addToPoint.z))
vertices.append(SCNVector3(vert.x - addToPoint.x, vert.y, vert.z + addToPoint.z))
vertices.append(vert + addToPoint)
vertices.append(vert - addToPoint)
if index > 0 {
addTriangleIndices(indices: &indices, at: UInt32(vertices.count - 2))
vertices.append(contentsOf: vertices[(vertices.count - 2)...])
}
}
}
Expand All @@ -149,14 +145,12 @@ public extension SCNGeometry {
texutreCoords.append(CGPoint(x: 0, y: val / pathLength))
texutreCoords.append(CGPoint(x: 1, y: val / pathLength))
}

let src = SCNGeometrySource(vertices: vertices)
let textureMap = SCNGeometrySource(textureCoordinates: texutreCoords)

// assuming the path is just flat for now, even though it can be angled
let norm = SCNGeometrySource(normals: [SCNVector3](
repeating: SCNVector3(0, 1, 0),
count: vertices.count
repeating: SCNVector3(0, 1, 0), count: vertices.count
))

// using triangles instead of triangleStrip for better normals
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