Files
gio-patched/widget/image.go
T
Elias Naur 94d242d18c op/paint: remove support for PaintOp.Rect
PaintOp.Rect is the wrong abstraction; it implies a clip operation
better handled by package clip, and not all paints need it (colors).
Furthermore, it's awkward to specify a PaintOp that fills up the
current clip area, regardless of its size.

Redefine PathOp to mean "fill current clip area".

API change. Replace uses of PaintOp.Rect with a TransformOp applied
before the PaintOp.

Leave a TODO for the PathOp infinity area.

Fixes gio#167

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-11-05 16:32:19 +01:00

42 lines
935 B
Go

// SPDX-License-Identifier: Unlicense OR MIT
package widget
import (
"image"
"gioui.org/layout"
"gioui.org/op"
"gioui.org/op/clip"
"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. If Scale is zero Image falls back to
// a scale that match a standard 72 DPI.
Scale float32
}
func (im Image) Layout(gtx layout.Context) layout.Dimensions {
scale := im.Scale
if scale == 0 {
scale = 160.0 / 72.0
}
size := im.Src.Size()
wf, hf := float32(size.X), float32(size.Y)
w, h := gtx.Px(unit.Dp(wf*scale)), gtx.Px(unit.Dp(hf*scale))
cs := gtx.Constraints
d := cs.Constrain(image.Pt(w, h))
stack := op.Push(gtx.Ops)
clip.Rect(image.Rectangle{Max: d}).Add(gtx.Ops)
im.Src.Add(gtx.Ops)
paint.PaintOp{}.Add(gtx.Ops)
stack.Pop()
return layout.Dimensions{Size: d}
}