all: initial import

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

ui/draw/draw.go

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+package draw
+
+import (
+	"image"
+	"math"
+
+	"gioui.org/ui/f32"
+	"gioui.org/ui/internal/path"
+	"gioui.org/ui"
+)
+
+type OpImage struct {
+	Rect    f32.Rectangle
+	Src     image.Image
+	SrcRect image.Rectangle
+}
+
+func (OpImage) ImplementsOp() {}
+
+// ClipRect returns a special case of OpClip
+// that clips to a pixel aligned rectangular area.
+func ClipRect(r image.Rectangle, op ui.Op) OpClip {
+	return OpClip{
+		Path: &Path{
+			data: &path.Path{
+				Bounds: toRectF(r),
+			},
+		},
+		Op: op,
+	}
+}
+
+func itof(i int) float32 {
+	switch i {
+	case ui.Inf:
+		return float32(math.Inf(+1))
+	case -ui.Inf:
+		return float32(math.Inf(-1))
+	default:
+		return float32(i)
+	}
+}
+
+func toRectF(r image.Rectangle) f32.Rectangle {
+	return f32.Rectangle{
+		Min: f32.Point{X: itof(r.Min.X), Y: itof(r.Min.Y)},
+		Max: f32.Point{X: itof(r.Max.X), Y: itof(r.Max.Y)},
+	}
+}