Files
gio/widget/material/image.go
T
2019-10-17 14:10:49 +02:00

45 lines
1021 B
Go

// SPDX-License-Identifier: Unlicense OR MIT
package material
import (
"image"
"gioui.org/f32"
"gioui.org/layout"
"gioui.org/op"
"gioui.org/op/paint"
"gioui.org/unit"
)
// Image is a widget that displays an image.
type Image struct {
// Src is the image to display.
Src paint.ImageOp
// Scale is the ratio of image pixels to
// dps.
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) {
size := im.Src.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))
cs := gtx.Constraints
d := image.Point{X: cs.Width.Constrain(w), Y: cs.Height.Constrain(h)}
var s op.StackOp
s.Push(gtx.Ops)
paint.RectClip(image.Rectangle{Max: d}).Add(gtx.Ops)
im.Src.Add(gtx.Ops)
paint.PaintOp{Rect: f32.Rectangle{Max: f32.Point{X: float32(w), Y: float32(h)}}}.Add(gtx.Ops)
s.Pop()
gtx.Dimensions = layout.Dimensions{Size: d}
}