fix form3.Cylinder. refactor threads

README.md

@@ -32,6 +32,7 @@ Here is a rendered bolt from one of the unit tests under [form3_test.go](./rende
 ## Roadmap
 - [ ] Add a 2D renderer and it's respective `Renderer2` interface.
 - [ ] Make 3D renderer multicore
+- [ ] Clean up thread API mess
 
 ## Comparison
 

form2/basic.go

@@ -56,8 +56,3 @@ func Line(l, round float64) (s sdf.SDF2, err error) {
 	}()
 	return must2.Line(l, round), err
 }
-
-// ThreadLookup lookups the parameters for a thread by name.
-func ThreadLookup(name string) (must2.ThreadParameters, error) {
-	return must2.ThreadLookup(name)
-}

form2/must2/thread.go → form2/obj2/thread.go

@@ -1,11 +1,12 @@
-package must2
+package obj2
 
 import (
 	"fmt"
 	"log"
 	"math"
 
 	"github.com/soypat/sdf"
+	"github.com/soypat/sdf/form2/must2"
 )
 
 // Screws
@@ -38,12 +39,10 @@ type threadDatabase map[string]ThreadParameters
 var threadDB = initThreadLookup()
 
 // UTSAdd adds a Unified Thread Standard to the thread database.
-func (m threadDatabase) UTSAdd(
-	name string, // thread name
-	diameter float64, // screw major diameter
-	tpi float64, // threads per inch
-	ftof float64, // hex head flat to flat distance
-) {
+// diameter is screw major diameter.
+// tpi is threads per inch.
+// ftof is hex head flat to flat distance.
+func (m threadDatabase) UTSAdd(name string, diameter float64, tpi float64, ftof float64) {
 	if ftof <= 0 {
 		log.Panicf("bad flat to flat distance for thread \"%s\"", name)
 	}
@@ -212,7 +211,7 @@ func AcmeThread(radius float64, pitch float64) sdf.SDF2 {
 	xOfs0 := 0.25*pitch - delta
 	xOfs1 := 0.25*pitch + delta
 
-	acme := NewPolygon()
+	acme := must2.NewPolygon()
 	acme.Add(radius, 0)
 	acme.Add(radius, h)
 	acme.Add(xOfs1, h)
@@ -222,7 +221,7 @@ func AcmeThread(radius float64, pitch float64) sdf.SDF2 {
 	acme.Add(-radius, h)
 	acme.Add(-radius, 0)
 
-	return Polygon(acme.Vertices())
+	return must2.Polygon(acme.Vertices())
 }
 
 // ISOThread returns the 2d profile for an ISO/UTS thread.
@@ -236,7 +235,7 @@ func ISOThread(radius float64, pitch float64, external bool) sdf.SDF2 {
 	rMajor := radius
 	r0 := rMajor - (7.0/8.0)*h
 
-	iso := NewPolygon()
+	iso := must2.NewPolygon()
 	if external {
 		rRoot := (pitch / 8.0) / math.Cos(theta)
 		xOfs := (1.0 / 16.0) * pitch
@@ -260,7 +259,7 @@ func ISOThread(radius float64, pitch float64, external bool) sdf.SDF2 {
 		iso.Add(-pitch, rMinor)
 		iso.Add(-pitch, 0)
 	}
-	return Polygon(iso.Vertices())
+	return must2.Polygon(iso.Vertices())
 }
 
 // ANSIButtressThread returns the 2d profile for an ANSI 45/7 buttress thread.
@@ -276,7 +275,7 @@ func ANSIButtressThread(radius float64, pitch float64) sdf.SDF2 {
 	h1 := ((b / 2.0) * pitch) + (0.5 * h0)
 	hp := pitch / 2.0
 
-	tp := NewPolygon()
+	tp := must2.NewPolygon()
 	tp.Add(pitch, 0)
 	tp.Add(pitch, radius)
 	tp.Add(hp-((h0-h1)*t1), radius)
@@ -285,7 +284,7 @@ func ANSIButtressThread(radius float64, pitch float64) sdf.SDF2 {
 	tp.Add(-pitch, radius)
 	tp.Add(-pitch, 0)
 
-	return Polygon(tp.Vertices())
+	return must2.Polygon(tp.Vertices())
 }
 
 // PlasticButtressThread returns the 2d profile for a screw top style plastic buttress thread.
@@ -300,7 +299,7 @@ func PlasticButtressThread(radius float64, pitch float64) sdf.SDF2 {
 	h1 := ((b / 2.0) * pitch) + (0.5 * h0)
 	hp := pitch / 2.0
 
-	tp := NewPolygon()
+	tp := must2.NewPolygon()
 	tp.Add(pitch, 0)
 	tp.Add(pitch, radius)
 	tp.Add(hp-((h0-h1)*t1), radius).Smooth(0.05*pitch, 5)
@@ -309,5 +308,7 @@ func PlasticButtressThread(radius float64, pitch float64) sdf.SDF2 {
 	tp.Add(-pitch, radius)
 	tp.Add(-pitch, 0)
 
-	return Polygon(tp.Vertices())
+	return must2.Polygon(tp.Vertices())
 }
+func d2r(degrees float64) float64 { return degrees * math.Pi / 180. }
+func r2d(radians float64) float64 { return radians / math.Pi * 180. }

form3/basic.go

@@ -56,7 +56,7 @@ func Cylinder(height, radius, round float64) (s sdf.SDF3, err error) {
 			}
 		}
 	}()
-	return must3.Sphere(radius), err
+	return must3.Cylinder(height, radius, round), err
 }
 
 // Capsule3D return an SDF3 for a capsule.

form3/must3/cylinders.go

@@ -109,11 +109,6 @@ func Cylinder(height, radius, round float64) *cylinder {
 	return &s
 }
 
-// Capsule3D return an SDF3 for a capsule.
-func Capsule(height, radius float64) *cylinder {
-	return Cylinder(height, radius, radius)
-}
-
 // Evaluate returns the minimum distance to a cylinder.
 func (s *cylinder) Evaluate(p r3.Vec) float64 {
 	d := sdfBox2d(r2.Vec{math.Hypot(p.X, p.Y), p.Z}, r2.Vec{s.radius, s.height})

form3/obj3/bolt.go

@@ -2,7 +2,7 @@ package obj3
 
 import (
 	"github.com/soypat/sdf"
-	form2 "github.com/soypat/sdf/form2/must2"
+	"github.com/soypat/sdf/form2/obj2"
 	form3 "github.com/soypat/sdf/form3/must3"
 	"gonum.org/v1/gonum/spatial/r3"
 )
@@ -21,7 +21,7 @@ type BoltParms struct {
 // Bolt returns a simple bolt suitable for 3d printing.
 func Bolt(k BoltParms) (s sdf.SDF3, err error) {
 	// validate parameters
-	t, err := form2.ThreadLookup(k.Thread)
+	t, err := obj2.ThreadLookup(k.Thread)
 	if err != nil {
 		panic(err)
 	}
@@ -63,7 +63,7 @@ func Bolt(k BoltParms) (s sdf.SDF3, err error) {
 	if threadLength != 0 {
 		r := t.Radius - k.Tolerance
 		threadOffset := threadLength/2 + shankLength
-		isoThread := form2.ISOThread(r, t.Pitch, true)
+		isoThread := obj2.ISOThread(r, t.Pitch, true)
 		thread = form3.Screw(isoThread, threadLength, t.Taper, t.Pitch, 1)
 		// chamfer the thread
 		thread = form3.ChamferedCylinder(thread, 0, 0.5)

form3/obj3/nut.go

@@ -2,7 +2,7 @@ package obj3
 
 import (
 	"github.com/soypat/sdf"
-	form2 "github.com/soypat/sdf/form2/must2"
+	"github.com/soypat/sdf/form2/obj2"
 	form3 "github.com/soypat/sdf/form3/must3"
 )
 
@@ -19,7 +19,7 @@ func Nut(k NutParms) (s sdf.SDF3, err error) {
 		panic("Tolerance < 0")
 	}
 	// validate parameters
-	t, err := form2.ThreadLookup(k.Thread)
+	t, err := obj2.ThreadLookup(k.Thread)
 	if err != nil {
 		panic(err)
 	}
@@ -40,7 +40,7 @@ func Nut(k NutParms) (s sdf.SDF3, err error) {
 	}
 
 	// internal thread
-	isoThread := form2.ISOThread(t.Radius+k.Tolerance, t.Pitch, false)
+	isoThread := obj2.ISOThread(t.Radius+k.Tolerance, t.Pitch, false)
 
 	thread := form3.Screw(isoThread, nh, t.Taper, t.Pitch, 1)
 	return sdf.Difference3D(nut, thread), err // TODO error handling

form3/screw.go

@@ -7,12 +7,12 @@ import (
 	"github.com/soypat/sdf/form3/must3"
 )
 
-// Screw returns a screw SDF3.
+// screw returns a screw SDF3.
 // - length of screw
 // - thread taper angle (radians)
 // - pitch thread to thread distance
 // - number of thread starts (< 0 for left hand threads)
-func Screw(thread sdf.SDF2, length, taper, pitch float64, starts int) (s sdf.SDF3, err error) {
+func screw(thread sdf.SDF2, length, taper, pitch float64, starts int) (s sdf.SDF3, err error) {
 	defer func() {
 		if a := recover(); a != nil {
 			err = &shapeErr{