all: [API] change clip.RRect and UniformRRect to take integer coordinates

Like the change to op.Offset before this, clip.RRect and UniformRRect
is usually used with integer coordinates. Change to integer coordinates
to eliminate many useless conversions to float32.

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

op/clip/shapes.go

@@ -37,7 +37,7 @@ func (r Rect) Path() PathSpec {
 
 // UniformRRect returns an RRect with all corner radii set to the
 // provided radius.
-func UniformRRect(rect f32.Rectangle, radius float32) RRect {
+func UniformRRect(rect image.Rectangle, radius int) RRect {
 	return RRect{
 		Rect: rect,
 		SE:   radius,
@@ -53,22 +53,15 @@ func UniformRRect(rect f32.Rectangle, radius float32) RRect {
 // Specify a square with corner radii equal to half the square size to
 // construct a circular clip area.
 type RRect struct {
-	Rect f32.Rectangle
+	Rect image.Rectangle
 	// The corner radii.
-	SE, SW, NW, NE float32
+	SE, SW, NW, NE int
 }
 
 // Op returns the op for the rounded rectangle.
 func (rr RRect) Op(ops *op.Ops) Op {
 	if rr.SE == 0 && rr.SW == 0 && rr.NW == 0 && rr.NE == 0 {
-		r := image.Rectangle{
-			Min: image.Point{X: int(rr.Rect.Min.X), Y: int(rr.Rect.Min.Y)},
-			Max: image.Point{X: int(rr.Rect.Max.X), Y: int(rr.Rect.Max.Y)},
-		}
-		// Only use Rect if rr is pixel-aligned, as Rect is guaranteed to be.
-		if fPt(r.Min) == rr.Rect.Min && fPt(r.Max) == rr.Rect.Max {
-			return Rect(r).Op()
-		}
+		return Rect(rr.Rect).Op()
 	}
 	return Outline{Path: rr.Path(ops)}.Op()
 }
@@ -87,8 +80,9 @@ func (rr RRect) Path(ops *op.Ops) PathSpec {
 	const q = 4 * (math.Sqrt2 - 1) / 3
 	const iq = 1 - q
 
-	se, sw, nw, ne := rr.SE, rr.SW, rr.NW, rr.NE
-	w, n, e, s := rr.Rect.Min.X, rr.Rect.Min.Y, rr.Rect.Max.X, rr.Rect.Max.Y
+	se, sw, nw, ne := float32(rr.SE), float32(rr.SW), float32(rr.NW), float32(rr.NE)
+	rrf := frect(rr.Rect)
+	w, n, e, s := rrf.Min.X, rrf.Min.Y, rrf.Max.X, rrf.Max.Y
 
 	p.MoveTo(f32.Point{X: w + nw, Y: n})
 	p.LineTo(f32.Point{X: e - ne, Y: n}) // N
@@ -117,7 +111,7 @@ func (rr RRect) Path(ops *op.Ops) PathSpec {
 
 // Ellipse represents the largest axis-aligned ellipse that
 // is contained in its bounds.
-type Ellipse f32.Rectangle
+type Ellipse image.Rectangle
 
 // Op returns the op for the filled ellipse.
 func (e Ellipse) Op(ops *op.Ops) Op {
@@ -131,7 +125,7 @@ func (e Ellipse) Push(ops *op.Ops) Stack {
 
 // Path constructs a path for the ellipse.
 func (e Ellipse) Path(o *op.Ops) PathSpec {
-	bounds := f32.Rectangle(e)
+	bounds := image.Rectangle(e)
 	if bounds.Dx() == 0 || bounds.Dy() == 0 {
 		return PathSpec{shape: ops.Rect}
 	}
@@ -139,12 +133,13 @@ func (e Ellipse) Path(o *op.Ops) PathSpec {
 	var p Path
 	p.Begin(o)
 
-	center := bounds.Max.Add(bounds.Min).Mul(.5)
-	diam := bounds.Dx()
+	bf := frect(bounds)
+	center := bf.Max.Add(bf.Min).Mul(.5)
+	diam := bf.Dx()
 	r := diam * .5
 	// We'll model the ellipse as a circle scaled in the Y
 	// direction.
-	scale := bounds.Dy() / diam
+	scale := bf.Dy() / diam
 
 	// https://pomax.github.io/bezierinfo/#circles_cubic.
 	const q = 4 * (math.Sqrt2 - 1) / 3
@@ -177,9 +172,3 @@ func (e Ellipse) Path(o *op.Ops) PathSpec {
 	ellipse.shape = ops.Ellipse
 	return ellipse
 }
-
-func fPt(p image.Point) f32.Point {
-	return f32.Point{
-		X: float32(p.X), Y: float32(p.Y),
-	}
-}

op/clip/shapes_test.go

@@ -1,17 +1,17 @@
 package clip_test
 
 import (
+	"image"
 	"image/color"
 	"testing"
 
-	"gioui.org/f32"
 	"gioui.org/op"
 	"gioui.org/op/clip"
 	"gioui.org/op/paint"
 )
 
 func TestZeroEllipse(t *testing.T) {
-	p := f32.Pt(1.0, 2.0)
+	p := image.Pt(1.0, 2.0)
 	e := clip.Ellipse{Min: p, Max: p}
 	ops := new(op.Ops)
 	paint.FillShape(ops, color.NRGBA{R: 255, A: 255}, e.Op(ops))