widget,widget/material: move Image and Icon to widget package

There is nothing theme-specific about displaying images and icons,
so move the types from the material package to the generic widget
package.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

widget/icon.go

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: Unlicense OR MIT
 
-package material
+package widget
 
 import (
 	"image"
@@ -29,7 +29,7 @@ func NewIcon(data []byte) (*Icon, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &Icon{src: data, Color: rgb(0x000000)}, nil
+	return &Icon{src: data, Color: color.RGBA{A: 0xff}}, nil
 }
 
 func (ic *Icon) Layout(gtx *layout.Context, sz unit.Value) {

widget/image.go

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: Unlicense OR MIT
 
-package material
+package widget
 
 import (
 	"image"
@@ -18,21 +18,19 @@ type Image struct {
 	// Src is the image to display.
 	Src paint.ImageOp
 	// Scale is the ratio of image pixels to
-	// dps.
+	// dps. If Scale is zero Image falls back to
+	// a scale that match a standard 72 DPI.
 	Scale float32
 }
 
-func (t *Theme) Image(img paint.ImageOp) Image {
-	return Image{
-		Src:   img,
-		Scale: 160 / 72, // About 72 DPI.
-	}
-}
-
 func (im Image) Layout(gtx *layout.Context) {
+	scale := im.Scale
+	if scale == 0 {
+		scale = 160.0 / 72.0
+	}
 	size := im.Src.Rect.Size()
 	wf, hf := float32(size.X), float32(size.Y)
-	w, h := gtx.Px(unit.Dp(wf*im.Scale)), gtx.Px(unit.Dp(hf*im.Scale))
+	w, h := gtx.Px(unit.Dp(wf*scale)), gtx.Px(unit.Dp(hf*scale))
 	cs := gtx.Constraints
 	d := image.Point{X: cs.Width.Constrain(w), Y: cs.Height.Constrain(h)}
 	var s op.StackOp
@@ -43,3 +41,7 @@ func (im Image) Layout(gtx *layout.Context) {
 	s.Pop()
 	gtx.Dimensions = layout.Dimensions{Size: d}
 }
+
+func toPointF(p image.Point) f32.Point {
+	return f32.Point{X: float32(p.X), Y: float32(p.Y)}
+}

widget/material/button.go

@@ -39,7 +39,7 @@ type ButtonLayout struct {
 type IconButton struct {
 	Background color.RGBA
 	Color      color.RGBA
-	Icon       *Icon
+	Icon       *widget.Icon
 	Size       unit.Value
 	Padding    unit.Value
 	Inset      layout.Inset
@@ -69,7 +69,7 @@ func (t *Theme) ButtonLayout() ButtonLayout {
 	}
 }
 
-func (t *Theme) IconButton(icon *Icon) IconButton {
+func (t *Theme) IconButton(icon *widget.Icon) IconButton {
 	return IconButton{
 		Background: t.Color.Primary,
 		Color:      t.Color.InvText,

widget/material/checkable.go

@@ -22,13 +22,12 @@ type checkable struct {
 	IconColor          color.RGBA
 	Size               unit.Value
 	shaper             text.Shaper
-	checkedStateIcon   *Icon
-	uncheckedStateIcon *Icon
+	checkedStateIcon   *widget.Icon
+	uncheckedStateIcon *widget.Icon
 }
 
 func (c *checkable) layout(gtx *layout.Context, checked bool) {
-
-	var icon *Icon
+	var icon *widget.Icon
 	if checked {
 		icon = c.checkedStateIcon
 	} else {

widget/material/theme.go

@@ -12,6 +12,7 @@ import (
 	"gioui.org/op/paint"
 	"gioui.org/text"
 	"gioui.org/unit"
+	"gioui.org/widget"
 	"golang.org/x/exp/shiny/materialdesign/icons"
 )
 
@@ -24,10 +25,10 @@ type Theme struct {
 		InvText color.RGBA
 	}
 	TextSize              unit.Value
-	checkBoxCheckedIcon   *Icon
-	checkBoxUncheckedIcon *Icon
-	radioCheckedIcon      *Icon
-	radioUncheckedIcon    *Icon
+	checkBoxCheckedIcon   *widget.Icon
+	checkBoxUncheckedIcon *widget.Icon
+	radioCheckedIcon      *widget.Icon
+	radioUncheckedIcon    *widget.Icon
 }
 
 func NewTheme() *Theme {
@@ -40,15 +41,15 @@ func NewTheme() *Theme {
 	t.Color.InvText = rgb(0xffffff)
 	t.TextSize = unit.Sp(16)
 
-	t.checkBoxCheckedIcon = mustIcon(NewIcon(icons.ToggleCheckBox))
-	t.checkBoxUncheckedIcon = mustIcon(NewIcon(icons.ToggleCheckBoxOutlineBlank))
-	t.radioCheckedIcon = mustIcon(NewIcon(icons.ToggleRadioButtonChecked))
-	t.radioUncheckedIcon = mustIcon(NewIcon(icons.ToggleRadioButtonUnchecked))
+	t.checkBoxCheckedIcon = mustIcon(widget.NewIcon(icons.ToggleCheckBox))
+	t.checkBoxUncheckedIcon = mustIcon(widget.NewIcon(icons.ToggleCheckBoxOutlineBlank))
+	t.radioCheckedIcon = mustIcon(widget.NewIcon(icons.ToggleRadioButtonChecked))
+	t.radioUncheckedIcon = mustIcon(widget.NewIcon(icons.ToggleRadioButtonUnchecked))
 
 	return t
 }
 
-func mustIcon(ic *Icon, err error) *Icon {
+func mustIcon(ic *widget.Icon, err error) *widget.Icon {
 	if err != nil {
 		panic(err)
 	}