add user input widget

7 files changed, 235 insertions, 569 deletions

diff --git a/go.mod b/go.mod
index 3eb3590..8a14268 100644
--- a/go.mod
+++ b/go.mod
@@ -3,19 +3,11 @@ module volute
 go 1.18
 
 require (
-	github.com/AllenDang/giu v0.6.2
 	github.com/BurntSushi/toml v1.1.0
+	github.com/faiface/mainthread v0.0.0-20171120011319-8b78f0a41ae3
+	github.com/go-gl/gl v0.0.0-20231021071112-07e5d0ea2e71
+	github.com/go-gl/glfw v0.0.0-20240108052320-294b0144ba39
+	golang.org/x/image v0.15.0
 )
 
-require (
-	github.com/AllenDang/go-findfont v0.0.0-20200702051237-9f180485aeb8 // indirect
-	github.com/AllenDang/imgui-go v1.12.1-0.20220322114136-499bbf6a42ad // indirect
-	github.com/faiface/mainthread v0.0.0-20171120011319-8b78f0a41ae3 // indirect
-	github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6 // indirect
-	github.com/go-gl/glfw/v3.3/glfw v0.0.0-20220320163800-277f93cfa958 // indirect
-	github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 // indirect
-	github.com/sahilm/fuzzy v0.1.0 // indirect
-	golang.org/x/image v0.0.0-20220302094943-723b81ca9867 // indirect
-	golang.org/x/sys v0.0.0-20220315194320-039c03cc5b86 // indirect
-	gopkg.in/eapache/queue.v1 v1.1.0 // indirect
-)
+require golang.org/x/text v0.14.0 // indirect
diff --git a/go.sum b/go.sum
index 074e02e..523443f 100644
--- a/go.sum
+++ b/go.sum
@@ -1,39 +1,12 @@
-github.com/AllenDang/giu v0.6.2 h1:CFIHSQxDqEFNsNnTO9LXBVZ8zlInV71H3M6V3BNagmI=
-github.com/AllenDang/giu v0.6.2/go.mod h1:9hCQh0l0wbBzOqe9cr02EB9EsNOy9AwFIjG4xVsR6TI=
-github.com/AllenDang/go-findfont v0.0.0-20200702051237-9f180485aeb8 h1:dKZMqib/yUDoCFigmz2agG8geZ/e3iRq304/KJXqKyw=
-github.com/AllenDang/go-findfont v0.0.0-20200702051237-9f180485aeb8/go.mod h1:b4uuDd0s6KRIPa84cEEchdQ9ICh7K0OryZHbSzMca9k=
-github.com/AllenDang/imgui-go v1.12.1-0.20220322114136-499bbf6a42ad h1:Kr961C2uEEAklK+jBRiZVnQH0AgS7o6pXrIgUTUUGiM=
-github.com/AllenDang/imgui-go v1.12.1-0.20220322114136-499bbf6a42ad/go.mod h1:kuPs9RWleaUuK7D49bE6HPxyRA36Lp4ICKGp+5OnnbY=
 github.com/BurntSushi/toml v1.1.0 h1:ksErzDEI1khOiGPgpwuI7x2ebx/uXQNw7xJpn9Eq1+I=
 github.com/BurntSushi/toml v1.1.0/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/faiface/mainthread v0.0.0-20171120011319-8b78f0a41ae3 h1:baVdMKlASEHrj19iqjARrPbaRisD7EuZEVJj6ZMLl1Q=
 github.com/faiface/mainthread v0.0.0-20171120011319-8b78f0a41ae3/go.mod h1:VEPNJUlxl5KdWjDvz6Q1l+rJlxF2i6xqDeGuGAxa87M=
-github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6 h1:zDw5v7qm4yH7N8C8uWd+8Ii9rROdgWxQuGoJ9WDXxfk=
-github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6/go.mod h1:9YTyiznxEY1fVinfM7RvRcjRHbw2xLBJ3AAGIT0I4Nw=
-github.com/go-gl/glfw/v3.3/glfw v0.0.0-20211213063430-748e38ca8aec/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
-github.com/go-gl/glfw/v3.3/glfw v0.0.0-20220320163800-277f93cfa958 h1:TL70PMkdPCt9cRhKTqsm+giRpgrd0IGEj763nNr2VFY=
-github.com/go-gl/glfw/v3.3/glfw v0.0.0-20220320163800-277f93cfa958/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
-github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
-github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 h1:KoWmjvw+nsYOo29YJK9vDA65RGE3NrOnUtO7a+RF9HU=
-github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8/go.mod h1:HKlIX3XHQyzLZPlr7++PzdhaXEj94dEiJgZDTsxEqUI=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
-github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/sahilm/fuzzy v0.1.0 h1:FzWGaw2Opqyu+794ZQ9SYifWv2EIXpwP4q8dY1kDAwI=
-github.com/sahilm/fuzzy v0.1.0/go.mod h1:VFvziUEIMCrT6A6tw2RFIXPXXmzXbOsSHF0DOI8ZK9Y=
-github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
-golang.org/x/image v0.0.0-20220302094943-723b81ca9867 h1:TcHcE0vrmgzNH1v3ppjcMGbhG5+9fMuvOmUYwNEF4q4=
-golang.org/x/image v0.0.0-20220302094943-723b81ca9867/go.mod h1:023OzeP/+EPmXeapQh35lcL3II3LrY8Ic+EFFKVhULM=
-golang.org/x/sys v0.0.0-20210616045830-e2b7044e8c71/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220315194320-039c03cc5b86 h1:A9i04dxx7Cribqbs8jf3FQLogkL/CV2YN7hj9KWJCkc=
-golang.org/x/sys v0.0.0-20220315194320-039c03cc5b86/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/eapache/queue.v1 v1.1.0 h1:EldqoJEGtXYiVCMRo2C9mePO2UUGnYn2+qLmlQSqPdc=
-gopkg.in/eapache/queue.v1 v1.1.0/go.mod h1:wNtmx1/O7kZSR9zNT1TTOJ7GLpm3Vn7srzlfylFbQwU=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+github.com/go-gl/gl v0.0.0-20231021071112-07e5d0ea2e71 h1:5BVwOaUSBTlVZowGO6VZGw2H/zl9nrd3eCZfYV+NfQA=
+github.com/go-gl/gl v0.0.0-20231021071112-07e5d0ea2e71/go.mod h1:9YTyiznxEY1fVinfM7RvRcjRHbw2xLBJ3AAGIT0I4Nw=
+github.com/go-gl/glfw v0.0.0-20240108052320-294b0144ba39 h1:NQ/PsAvvBcCUiFODaU3tmnKesYruVJL+Dx5hTRrr+DA=
+github.com/go-gl/glfw v0.0.0-20240108052320-294b0144ba39/go.mod h1:wyvWpaEu9B/VQiV1jsPs7Mha9I7yto/HqIBw197ZAzk=
+golang.org/x/image v0.15.0 h1:kOELfmgrmJlw4Cdb7g/QGuB3CvDrXbqEIww/pNtNBm8=
+golang.org/x/image v0.15.0/go.mod h1:HUYqC05R2ZcZ3ejNQsIHQDQiwWM4JBqmm6MKANTp4LE=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
diff --git a/gui/widget/concurrent_face.go b/gui/widget/concurrent_face.go
new file mode 100644
index 0000000..98db572
--- /dev/null
+++ b/gui/widget/concurrent_face.go
@@ -0,0 +1,51 @@
+package widget
+
+import (
+	"image"
+	"sync"
+
+	"golang.org/x/image/font"
+	"golang.org/x/image/math/fixed"
+)
+
+type concurrentFace struct {
+	mu   sync.Mutex
+	face font.Face
+}
+
+func (cf *concurrentFace) Close() error {
+	cf.mu.Lock()
+	defer cf.mu.Unlock()
+	return cf.face.Close()
+}
+
+func (cf *concurrentFace) Glyph(dot fixed.Point26_6, r rune) (
+	dr image.Rectangle, mask image.Image, maskp image.Point, advance fixed.Int26_6, ok bool) {
+	cf.mu.Lock()
+	defer cf.mu.Unlock()
+	return cf.face.Glyph(dot, r)
+}
+
+func (cf *concurrentFace) GlyphBounds(r rune) (bounds fixed.Rectangle26_6, advance fixed.Int26_6, ok bool) {
+	cf.mu.Lock()
+	defer cf.mu.Unlock()
+	return cf.face.GlyphBounds(r)
+}
+
+func (cf *concurrentFace) GlyphAdvance(r rune) (advance fixed.Int26_6, ok bool) {
+	cf.mu.Lock()
+	defer cf.mu.Unlock()
+	return cf.face.GlyphAdvance(r)
+}
+
+func (cf *concurrentFace) Kern(r0, r1 rune) fixed.Int26_6 {
+	cf.mu.Lock()
+	defer cf.mu.Unlock()
+	return cf.face.Kern(r0, r1)
+}
+
+func (cf *concurrentFace) Metrics() font.Metrics {
+	cf.mu.Lock()
+	defer cf.mu.Unlock()
+	return cf.face.Metrics()
+}
diff --git a/gui/widget/text.go b/gui/widget/text.go
new file mode 100644
index 0000000..cb66a0a
--- /dev/null
+++ b/gui/widget/text.go
@@ -0,0 +1,74 @@
+package widget
+
+import (
+	"log"
+	"sync"
+
+	"image"
+	"image/draw"
+
+	"golang.org/x/image/font"
+	"golang.org/x/image/font/gofont/goregular"
+	"golang.org/x/image/font/opentype"
+	"golang.org/x/image/math/fixed"
+)
+
+var (
+	FONT               = goregular.TTF
+	FONT_SIZE  float64 = 15
+	DPI        float64 = 72
+	BG_COLOR           = image.White
+	TEXT_COLOR         = image.Black
+)
+
+var face *concurrentFace
+
+func init() {
+	fnt, err := opentype.Parse(FONT)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fce, err := opentype.NewFace(fnt, &opentype.FaceOptions{
+		Size: FONT_SIZE,
+		DPI:  DPI,
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+	face = &concurrentFace{sync.Mutex{}, fce}
+}
+
+func drawText(text []byte, dst draw.Image, r image.Rectangle) {
+	drawer := font.Drawer{
+		Src:  TEXT_COLOR,
+		Face: face,
+		Dot:  fixed.P(0, 0),
+	}
+
+	bounds := textBounds(text, drawer)
+
+	// background
+	draw.Draw(dst, r, BG_COLOR, image.ZP, draw.Src)
+
+	// text image
+	textImg := image.NewRGBA(bounds)
+	draw.Draw(textImg, bounds, BG_COLOR, image.ZP, draw.Src)
+	drawer.Dst = textImg
+	drawer.DrawBytes(text)
+
+	// draw text image over background
+	left := image.Pt(bounds.Min.X, (bounds.Min.Y+bounds.Max.Y)/2)
+	target := image.Pt(r.Min.X, (r.Min.Y+r.Max.Y)/2)
+	delta := target.Sub(left)
+	draw.Draw(dst, bounds.Add(delta).Intersect(r), drawer.Dst, bounds.Min, draw.Src)
+}
+
+func textBounds(text []byte, drawer font.Drawer) image.Rectangle {
+	b, _ := drawer.BoundBytes(text)
+	return image.Rect(
+		b.Min.X.Floor(),
+		b.Min.Y.Floor(),
+		b.Max.X.Ceil(),
+		b.Max.Y.Ceil(),
+	)
+}
diff --git a/gui/widget/widget.go b/gui/widget/widget.go
new file mode 100644
index 0000000..913809b
--- /dev/null
+++ b/gui/widget/widget.go
@@ -0,0 +1,65 @@
+package widget
+
+import (
+	"cmp"
+	"fmt"
+
+	"image"
+	"image/draw"
+
+	"volute/gui"
+	"volute/gui/win"
+)
+
+func Input(env gui.Env, r image.Rectangle, val chan<- float64) {
+	redraw := func(text []byte) func(draw.Image) image.Rectangle {
+		return func(drw draw.Image) image.Rectangle {
+			drawText(text, drw, r)
+			return r
+		}
+	}
+	text := []byte{'0'}
+	focus := false
+
+	env.Draw() <- redraw(text)
+
+	for event := range env.Events() {
+		switch event := event.(type) {
+		case win.WiFocus:
+			if event.Focused {
+				env.Draw() <- redraw(text)
+			}
+		case win.MoDown:
+			if event.Point.In(r) {
+				focus = true
+			}
+		case win.KbType:
+			if !focus ||
+				(!isDigit(event.Rune) && event.Rune != '.') ||
+				(event.Rune == '.' && contains(text, '.')) {
+				continue
+			}
+			text = fmt.Appendf(text, "%c", event.Rune)
+			env.Draw() <- redraw(text)
+		case win.KbDown:
+			if event.Key == win.KeyBackspace && len(text) > 0 {
+				text = text[:len(text)-1]
+				env.Draw() <- redraw(text)
+			}
+		}
+	}
+	close(env.Draw())
+}
+
+func isDigit(r rune) bool {
+	return '0' <= r && r <= '9'
+}
+
+func contains[T cmp.Ordered](slc []T, v T) bool {
+	for i := range slc {
+		if slc[i] == v {
+			return true
+		}
+	}
+	return false
+}
diff --git a/main.go b/main.go
index 491aa80..c6c522f 100644
--- a/main.go
+++ b/main.go
@@ -1,155 +1,47 @@
 package main
 
 import (
-	"fmt"
-	g "github.com/AllenDang/giu"
 	"image"
-	"image/draw"
-	_ "image/jpeg"
-	"os"
 
-	"volute/compressor"
-	"volute/mass"
-	"volute/pressure"
-	"volute/temperature"
-	"volute/util"
-	"volute/volume"
+	"github.com/faiface/mainthread"
+	"volute/gui"
+	"volute/gui/widget"
+	"volute/gui/win"
 )
 
-const (
-	gasConstant  = 8.314472
-	airMolarMass = 0.0289647 // kg/mol
-)
-
-// numPoints is the number of datapoints on the compressor map.
-var numPoints = 1
-
-var (
-	displacement = 2000 * volume.CubicCentimetre
-	// volumeUnitIndex is used to index volume.UnitStrings().
-	volumeUnitIndex = volume.DefaultUnitIndex
-
-	engineSpeed = []int32{2000}
-
-	volumetricEfficiency = []int32{80}
-
-	intakeAirTemperature = []temperature.Temperature{{25, temperature.Celcius}}
-	// temperatureUnitIndex is used to index temperature.UnitStrings().
-	temperatureUnitIndex = temperature.DefaultUnitIndex
-
-	manifoldPressure = []pressure.Pressure{pressure.Atmospheric()}
-	// pressureUnitIndex is used to index pressure.UnitStrings().
-	pressureUnitIndex = pressure.DefaultUnitIndex
-)
-
-var pressureRatio []float32
-
-func pressureRatioAt(point int) float32 {
-	u := pressure.Pascal
-	m := manifoldPressure[point] / u
-	a := pressure.Atmospheric() / u
-	return float32(m / a)
-}
-func init() {
-	pressureRatio = append(pressureRatio, pressureRatioAt(0))
-}
-
-var (
-	engineMassFlowRate []mass.FlowRate
-	// selectedMassFlowRateUnit is used to index mass.FlowRateUnitStrings().
-	selectedMassFlowRateUnit = mass.DefaultFlowRateUnitIndex
-)
-
-func massFlowRateAt(point int) mass.FlowRate {
-	rpm := float32(engineSpeed[point])
-	disp := float32(displacement / volume.CubicMetre)
-	ve := float32(volumetricEfficiency[point]) / 100.0
-	cubicMetresPerMin := (rpm / 2.0) * disp * ve
-
-	iat, err := intakeAirTemperature[point].AsUnit(temperature.Kelvin)
-	util.Check(err)
-	pres := manifoldPressure[point] / pressure.Pascal
-	molsPerMin := (float32(pres) * cubicMetresPerMin) / (gasConstant * iat)
-
-	kgPerMin := molsPerMin * airMolarMass
+func run() {
+	w, err := win.New(win.Title("volute"), win.Size(800, 600))
+	if err != nil {
+		panic(err)
+	}
 
-	mfr := mass.FlowRate(kgPerMin/60.0) * mass.KilogramsPerSecond
-	return mfr
-}
-func init() {
-	engineMassFlowRate = append(engineMassFlowRate, massFlowRateAt(0))
-}
+	mux, env := gui.NewMux(w)
 
-var (
-	compressorImage    *image.RGBA
-	compressorTexture  *g.Texture
-	selectedCompressor compressor.Compressor
-)
+	var (
+		displacementChan = make(chan float64)
+	)
 
-func init() {
-	manufacturer := "garrett"
-	series := "g"
-	model := "25-660"
-	c, ok := compressor.Compressors()[manufacturer][series][model]
-	if !ok {
-		fmt.Printf("compressor.Compressors()[\"%s\"][\"%s\"][\"%s\"] does not exist.\n",
-			manufacturer, series, model,
-		)
-		os.Exit(1)
+	go widget.Input(mux.MakeEnv(), image.Rect(20, 20, 100, 40), displacementChan)
+
+Loop:
+	for event := range env.Events() {
+		switch event := event.(type) {
+		case win.WiClose:
+			break Loop
+		case win.KbType:
+			if event.Rune == 'q' {
+				break Loop
+			}
+		}
+		select {
+		case _ = <-displacementChan:
+		default:
+		}
 	}
-
-	setCompressor(c)
+	close(env.Draw())
+	close(displacementChan)
 }
 
 func main() {
-	wnd := g.NewMasterWindow("volute", 400, 200, 0)
-
-	go updateCompImg()
-	m := <-updatedCompImg
-	g.EnqueueNewTextureFromRgba(m, func(tex *g.Texture) {
-		compressorTexture = tex
-	})
-
-	wnd.Run(loop)
-}
-
-func setCompressor(c compressor.Compressor) {
-	f, err := os.Open(c.FileName)
-	util.Check(err)
-	defer f.Close()
-
-	j, _, err := image.Decode(f)
-	util.Check(err)
-
-	b := j.Bounds()
-	m := image.NewRGBA(image.Rect(0, 0, b.Dx(), b.Dy()))
-	draw.Draw(m, m.Bounds(), j, b.Min, draw.Src)
-
-	selectedCompressor = c
-	compressorImage = m
-
-	go updateCompImg()
-}
-
-func loop() {
-	g.SingleWindow().Layout(
-		engineDisplacementRow(),
-		g.Table().
-			Size(g.Auto, 190).
-			Rows(
-				engineSpeedRow(),
-				volumetricEfficiencyRow(),
-				intakeAirTemperatureRow(),
-				manifoldPressureRow(),
-				pressureRatioRow(),
-				massFlowRateRow(),
-				duplicateDeleteRow(),
-			).
-			Columns(
-				columns()...,
-			).
-			Flags(g.TableFlagsSizingFixedFit),
-		selectCompressor(),
-		g.Custom(compressorWidget),
-	)
+	mainthread.Run(run)
 }
diff --git a/ui.go b/ui.go
deleted file mode 100644
index 118069d..0000000
--- a/ui.go
+++ /dev/null
@@ -1,381 +0,0 @@
-package main
-
-import (
-	"fmt"
-	g "github.com/AllenDang/giu"
-	"image"
-	"image/color"
-	"image/draw"
-	"strconv"
-
-	"volute/compressor"
-	"volute/mass"
-	"volute/pressure"
-	"volute/temperature"
-	"volute/util"
-	"volute/volume"
-)
-
-func red() color.RGBA {
-	return color.RGBA{255, 0, 0, 255}
-}
-
-func engineDisplacementRow() *g.RowWidget {
-	s := volume.UnitStrings()[volumeUnitIndex]
-	unit, err := volume.UnitFromString(s)
-	util.Check(err)
-	engDisp := float32(displacement / unit)
-	valWid, _ := g.CalcTextSize("12345.67")
-	unitWid, _ := g.CalcTextSize(volume.UnitStrings()[volumeUnitIndex])
-	return g.Row(
-		g.Label("Engine Displacement"),
-		g.InputFloat(&engDisp).
-			Format("%.2f").
-			OnChange(func() {
-				displacement = volume.Volume(engDisp) * unit
-				for i := 0; i < numPoints; i++ {
-					engineMassFlowRate[i] = massFlowRateAt(i)
-					go updateCompImg()
-				}
-			}).
-			Size(valWid),
-		g.Combo(
-			"",
-			volume.UnitStrings()[volumeUnitIndex],
-			volume.UnitStrings(),
-			&volumeUnitIndex,
-		).Size(unitWid*2),
-	)
-}
-
-func engineSpeedRow() *g.TableRowWidget {
-	widgets := []g.Widget{
-		g.Label("Engine Speed"),
-		g.Label("rpm"),
-	}
-	for i := 0; i < numPoints; i++ {
-		i := i
-		widgets = append(
-			widgets,
-			g.InputInt(&engineSpeed[i]).OnChange(func() {
-				engineMassFlowRate[i] = massFlowRateAt(i)
-				go updateCompImg()
-			}),
-		)
-	}
-	return g.TableRow(widgets...)
-}
-
-func volumetricEfficiencyRow() *g.TableRowWidget {
-	widgets := []g.Widget{
-		g.Label("Volumetric Efficiency"),
-		g.Label("%"),
-	}
-	for i := 0; i < numPoints; i++ {
-		i := i
-		widgets = append(
-			widgets,
-			g.InputInt(&volumetricEfficiency[i]).OnChange(func() {
-				engineMassFlowRate[i] = massFlowRateAt(i)
-				go updateCompImg()
-			}),
-		)
-	}
-	return g.TableRow(widgets...)
-}
-
-func intakeAirTemperatureRow() *g.TableRowWidget {
-	wid, _ := g.CalcTextSize(temperature.UnitStrings()[temperatureUnitIndex])
-	widgets := []g.Widget{
-		g.Label("Intake Air Temperature"),
-		g.Combo(
-			"",
-			temperature.UnitStrings()[temperatureUnitIndex],
-			temperature.UnitStrings(),
-			&temperatureUnitIndex,
-		).OnChange(func() {
-			s := temperature.UnitStrings()[temperatureUnitIndex]
-			u, err := temperature.UnitFromString(s)
-			util.Check(err)
-
-			for i := range intakeAirTemperature {
-				t, err := intakeAirTemperature[i].AsUnit(u)
-				util.Check(err)
-				intakeAirTemperature[i] = temperature.Temperature{t, u}
-			}
-		}).Size(wid * 2),
-	}
-	for i := 0; i < numPoints; i++ {
-		i := i
-		widgets = append(
-			widgets,
-			g.InputFloat(&intakeAirTemperature[i].Val).
-				Format("%.2f").
-				OnChange(func() {
-					engineMassFlowRate[i] = massFlowRateAt(i)
-					go updateCompImg()
-				}),
-		)
-	}
-	return g.TableRow(widgets...)
-}
-
-func manifoldPressureRow() *g.TableRowWidget {
-	s := pressure.UnitStrings()[pressureUnitIndex]
-	unit, err := pressure.UnitFromString(s)
-	util.Check(err)
-	wid, _ := g.CalcTextSize(pressure.UnitStrings()[pressureUnitIndex])
-	widgets := []g.Widget{
-		g.Label("Manifold Absolute Pressure"),
-		g.Combo(
-			"",
-			pressure.UnitStrings()[pressureUnitIndex],
-			pressure.UnitStrings(),
-			&pressureUnitIndex,
-		).Size(wid * 2),
-	}
-	for i := 0; i < numPoints; i++ {
-		i := i
-		manPres := float32(manifoldPressure[i] / unit)
-		widgets = append(
-			widgets,
-			g.InputFloat(&manPres).Format("%.2f").
-				OnChange(func() {
-					manifoldPressure[i] = pressure.Pressure(manPres * float32(unit))
-					pressureRatio[i] = pressureRatioAt(i)
-					engineMassFlowRate[i] = massFlowRateAt(i)
-					go updateCompImg()
-				}),
-		)
-	}
-	return g.TableRow(widgets...)
-}
-
-func pressureRatioRow() *g.TableRowWidget {
-	widgets := []g.Widget{
-		g.Label("Pressure Ratio"),
-		g.Label(""),
-	}
-	for i := 0; i < numPoints; i++ {
-		pr := strconv.FormatFloat(float64(pressureRatio[i]), 'f', 1, 32)
-		widgets = append(
-			widgets,
-			g.Label(pr),
-		)
-	}
-	return g.TableRow(widgets...)
-}
-
-func massFlowRateRow() *g.TableRowWidget {
-	s := mass.FlowRateUnitStrings()[selectedMassFlowRateUnit]
-	mfrUnit, err := mass.FlowRateUnitFromString(s)
-	util.Check(err)
-
-	wid, _ := g.CalcTextSize(mass.FlowRateUnitStrings()[selectedMassFlowRateUnit])
-	widgets := []g.Widget{
-		g.Label("Mass Flow Rate"),
-		g.Combo(
-			"",
-			mass.FlowRateUnitStrings()[selectedMassFlowRateUnit],
-			mass.FlowRateUnitStrings(),
-			&selectedMassFlowRateUnit,
-		).Size(wid * 2),
-	}
-	for i := 0; i < numPoints; i++ {
-		mfr := strconv.FormatFloat(
-			float64(engineMassFlowRate[i]/mfrUnit),
-			'f',
-			3,
-			32,
-		)
-		widgets = append(
-			widgets,
-			g.Label(mfr),
-		)
-	}
-	return g.TableRow(widgets...)
-}
-
-func duplicateDeleteRow() *g.TableRowWidget {
-	widgets := []g.Widget{g.Label(""), g.Label("")}
-	for i := 0; i < numPoints; i++ {
-		i := i
-		widgets = append(widgets, g.Row(
-			g.Button("Duplicate").OnClick(func() {
-				numPoints++
-				engineSpeed = util.Insert(
-					engineSpeed,
-					engineSpeed[i],
-					i,
-				)
-				volumetricEfficiency = util.Insert(
-					volumetricEfficiency,
-					volumetricEfficiency[i],
-					i,
-				)
-				intakeAirTemperature = util.Insert(
-					intakeAirTemperature,
-					intakeAirTemperature[i],
-					i,
-				)
-				manifoldPressure = util.Insert(
-					manifoldPressure,
-					manifoldPressure[i],
-					i,
-				)
-				pressureRatio = util.Insert(
-					pressureRatio,
-					pressureRatio[i],
-					i,
-				)
-				engineMassFlowRate = util.Insert(
-					engineMassFlowRate,
-					engineMassFlowRate[i],
-					i,
-				)
-				go updateCompImg()
-			}),
-			g.Button("Delete").OnClick(func() {
-				if numPoints < 2 {
-					return
-				}
-				numPoints--
-				engineSpeed = util.Remove(engineSpeed, i)
-				volumetricEfficiency = util.Remove(volumetricEfficiency, i)
-				intakeAirTemperature = util.Remove(intakeAirTemperature, i)
-				manifoldPressure = util.Remove(manifoldPressure, i)
-				pressureRatio = util.Remove(pressureRatio, i)
-				engineMassFlowRate = util.Remove(engineMassFlowRate, i)
-				go updateCompImg()
-			}),
-		))
-	}
-	return g.TableRow(widgets...)
-}
-
-func columns() []*g.TableColumnWidget {
-	widgets := []*g.TableColumnWidget{
-		g.TableColumn("Parameter"),
-		g.TableColumn("Unit"),
-	}
-	for i := 0; i < numPoints; i++ {
-		widgets = append(
-			widgets,
-			g.TableColumn(fmt.Sprintf("Point %d", i+1)),
-		)
-	}
-	return widgets
-}
-
-var compressorTree []g.Widget
-
-func init() {
-	compressors := compressor.Compressors()
-	for man := range compressors {
-		man := man // Manufacturer
-		var serNodes []g.Widget
-		for ser := range compressors[man] {
-			ser := ser // Series
-			var modNodes []g.Widget
-			for mod, c := range compressors[man][ser] {
-				mod := mod // Model
-				c := c     // Compressor
-				modNodes = append(
-					modNodes,
-					g.Selectable(mod).OnClick(func() {
-						go setCompressor(c)
-					}),
-				)
-			}
-			serNodes = append(
-				serNodes,
-				g.TreeNode(ser).Layout(modNodes...),
-			)
-		}
-		manNode := g.TreeNode(man).Layout(serNodes...)
-		compressorTree = append(compressorTree, manNode)
-	}
-}
-
-func selectCompressor() g.Widget {
-	return g.ComboCustom("Compressor", selectedCompressor.Name).
-		Layout(compressorTree...)
-}
-
-var updatedCompImg = make(chan image.Image)
-
-func updateCompImg() {
-	img := copyImage(compressorImage)
-	for i := 0; i < numPoints; i++ {
-		pos := pointPos(i)
-		ps := img.Bounds().Dx() / 100 // Point size
-		draw.Draw(img,
-			image.Rect(pos.X-ps/2, pos.Y-ps/2, pos.X+ps/2, pos.Y+ps/2),
-			&image.Uniform{red()},
-			image.ZP,
-			draw.Src,
-		)
-	}
-	updatedCompImg <- img
-}
-
-func compressorWidget() {
-	select {
-	case m := <-updatedCompImg:
-		g.EnqueueNewTextureFromRgba(m, func(tex *g.Texture) {
-			compressorTexture = tex
-		})
-	default:
-	}
-
-	canvas := g.GetCanvas()
-	if compressorTexture != nil {
-		winWidth, winHeight := g.GetAvailableRegion()
-
-		bounds := compressorImage.Bounds()
-		imWidth := float32(bounds.Dx())
-		imHeight := float32(bounds.Dy())
-
-		var ratio, xratio, yratio float32
-		xratio = winWidth / imWidth
-		yratio = winHeight / imHeight
-		if xratio < yratio {
-			ratio = xratio
-		} else {
-			ratio = yratio
-		}
-
-		x := int(imWidth * ratio)
-		y := int(imHeight * ratio)
-
-		canvas.AddImage(
-			compressorTexture,
-			image.Pt(0, 250),
-			image.Pt(x, y),
-		)
-	}
-}
-
-func copyImage(old *image.RGBA) *image.RGBA {
-	b := old.Bounds()
-	img := image.NewRGBA(image.Rect(0, 0, b.Dx(), b.Dy()))
-	draw.Draw(img, img.Bounds(), old, b.Min, draw.Src)
-	return img
-}
-
-// The position on the compressor map of an operating point.
-func pointPos(i int) (pos image.Point) {
-	const unit = mass.KilogramsPerSecond
-	mfr := engineMassFlowRate[i] / unit
-	maxMfr := selectedCompressor.MaxFlow / unit
-	min := selectedCompressor.MinX
-	max := selectedCompressor.MaxX
-	pos.X = min + int(float32(max-min)*float32(mfr/maxMfr))
-
-	min = selectedCompressor.MinY
-	max = selectedCompressor.MaxY
-	pr := pressureRatio[i]
-	maxPr := selectedCompressor.MaxPR
-	pos.Y = min - int(float32((min-max))*((pr-1.0)/(maxPr-1.0)))
-	return pos
-}