gpu,widget,op/paint,gpu: remove support for ImageOp.Rect

This is effectively a revert of commit gioui.org/commit/69dfd2e3a5541.

ImageOp.Rect is the wrong abstraction; it implies a clipping operation that is
better handled by package clip.

API change. Uses of ImageOp.Rect should apply a clip.Rect before the PaintOp,
or use image.RGBA.SubImage (or similar).

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

gpu/gpu.go

@@ -130,7 +130,6 @@ type clipOp struct {
 
 // imageOpData is the shadow of paint.ImageOp.
 type imageOpData struct {
-	rect   image.Rectangle
 	src    *image.RGBA
 	handle interface{}
 }
@@ -170,18 +169,7 @@ func decodeImageOp(data []byte, refs []interface{}) imageOpData {
 	if handle == nil {
 		return imageOpData{}
 	}
-	bo := binary.LittleEndian
 	return imageOpData{
-		rect: image.Rectangle{
-			Min: image.Point{
-				X: int(int32(bo.Uint32(data[1:]))),
-				Y: int(int32(bo.Uint32(data[5:]))),
-			},
-			Max: image.Point{
-				X: int(int32(bo.Uint32(data[9:]))),
-				Y: int(int32(bo.Uint32(data[13:]))),
-			},
-		},
 		src:    refs[0].(*image.RGBA),
 		handle: handle,
 	}
@@ -962,7 +950,12 @@ func (d *drawState) materialFor(cache *resourceCache, rect f32.Rectangle, off f3
 		m.material = materialTexture
 		dr := boundRectF(rect.Add(off))
 		sz := d.image.src.Bounds().Size()
-		sr := layout.FRect(d.image.rect)
+		sr := f32.Rectangle{
+			Max: f32.Point{
+				X: float32(sz.X),
+				Y: float32(sz.Y),
+			},
+		}
 		if dx := float32(dr.Dx()); dx != 0 {
 			// Don't clip 1 px width sources.
 			if sdx := sr.Dx(); sdx > 1 {

internal/opconst/ops.go

@@ -35,7 +35,7 @@ const (
 	TypeTransformLen      = 1 + 4*6
 	TypeLayerLen          = 1
 	TypeRedrawLen         = 1 + 8
-	TypeImageLen          = 1 + 4*4
+	TypeImageLen          = 1
 	TypePaintLen          = 1 + 4*4
 	TypeColorLen          = 1 + 4
 	TypeLinearGradientLen = 1 + 8*2 + 4*2

op/paint/paint.go

@@ -20,9 +20,6 @@ import (
 // Note: the ImageOp may keep a reference to the backing image.
 // See NewImageOp for details.
 type ImageOp struct {
-	// Rect is the section if the backing image to use.
-	Rect image.Rectangle
-
 	uniform bool
 	color   color.RGBA
 	src     *image.RGBA
@@ -74,7 +71,6 @@ func NewImageOp(src image.Image) ImageOp {
 		bounds := src.Bounds()
 		if bounds.Min == (image.Point{}) && src.Stride == bounds.Dx()*4 {
 			return ImageOp{
-				Rect:   src.Bounds(),
 				src:    src,
 				handle: new(int),
 			}
@@ -88,7 +84,6 @@ func NewImageOp(src image.Image) ImageOp {
 	})
 	draw.Draw(dst, dst.Bounds(), src, src.Bounds().Min, draw.Src)
 	return ImageOp{
-		Rect:   dst.Bounds(),
 		src:    dst,
 		handle: new(int),
 	}
@@ -110,11 +105,6 @@ func (i ImageOp) Add(o *op.Ops) {
 	}
 	data := o.Write(opconst.TypeImageLen, i.src, i.handle)
 	data[0] = byte(opconst.TypeImage)
-	bo := binary.LittleEndian
-	bo.PutUint32(data[1:], uint32(i.Rect.Min.X))
-	bo.PutUint32(data[5:], uint32(i.Rect.Min.Y))
-	bo.PutUint32(data[9:], uint32(i.Rect.Max.X))
-	bo.PutUint32(data[13:], uint32(i.Rect.Max.Y))
 }
 
 func (c ColorOp) Add(o *op.Ops) {

widget/image.go

@@ -28,7 +28,7 @@ func (im Image) Layout(gtx layout.Context) layout.Dimensions {
 	if scale == 0 {
 		scale = 160.0 / 72.0
 	}
-	size := im.Src.Rect.Size()
+	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