From ce116abdedab45e77c42317ea5d5fb6516c043df Mon Sep 17 00:00:00 2001
From: Elias Naur <mail@eliasnaur.com>
Date: Thu, 10 Feb 2022 18:59:47 +0100
Subject: [PATCH] op/clip: specify path for stroked Rects

Fixes: https://todo.sr.ht/~eliasnaur/gio/358
Signed-off-by: Elias Naur <mail@eliasnaur.com>
---
 gpu/internal/rendertest/clip_test.go          |  14 +++++++++
 .../rendertest/refs/TestStrokedRect.png       | Bin 0 -> 564 bytes
 op/clip/clip.go                               |  28 ++++++++++++++++++
 3 files changed, 42 insertions(+)
 create mode 100644 gpu/internal/rendertest/refs/TestStrokedRect.png

diff --git a/gpu/internal/rendertest/clip_test.go b/gpu/internal/rendertest/clip_test.go
index 3a147312..6a5ad9ae 100644
--- a/gpu/internal/rendertest/clip_test.go
+++ b/gpu/internal/rendertest/clip_test.go
@@ -277,3 +277,17 @@ func TestPathInterleave(t *testing.T) {
 		paint.ColorOp{}.Add(ops)
 	})
 }
+
+func TestStrokedRect(t *testing.T) {
+	run(t, func(o *op.Ops) {
+		r := clip.Rect{Min: image.Pt(50, 50), Max: image.Pt(100, 100)}
+		paint.FillShape(o,
+			color.NRGBA{R: 0xff, A: 0xFF},
+			clip.Stroke{
+				Path:  r.Path(),
+				Width: 5,
+			}.Op(),
+		)
+	}, func(r result) {
+	})
+}
diff --git a/gpu/internal/rendertest/refs/TestStrokedRect.png b/gpu/internal/rendertest/refs/TestStrokedRect.png
new file mode 100644
index 0000000000000000000000000000000000000000..77b74a46ed85508d5fde8049910bde7bdf58fafb
GIT binary patch
literal 564
zcmeAS@N?(olHy`uVBq!ia0vp^4Is?H1|$#LC7xzrVEpar;uumf=gr-NzK0DY+&|W9
zi7_0UsCuJKCpe-lH-U2<hgn9zQm>dDE}nl+*1g~EV0V3ek>5u}Cu0T+<_7u_yI0C3
ztXAFWZ=`=R_Nz|yj7jfR@`FEJeNp*$SI$58NylGBmVKM~WTh+1UU|mP4YTK;p7l(O
z|CMdS?N^NJR-C+5#qS_p`d{eBeAUXe^AdYCEyHZ9cQBlrUGEXM>UqTD5Q#>2hB=G}
zB<VujDY(xyZ_?wHRUK3RM0`1?Re#}L1<Qf2atHjsGF;ze5*7V^x|^*^rTm9`3(}^$
zmC8E&Q>u`A`ftH!`}(Yk+&K@b>e(;2u`#4G6p%xFmu6u2|Gy|s?xSh)t);-!z~JfX
K=d#Wzp$P!EI=_to

literal 0
HcmV?d00001

diff --git a/op/clip/clip.go b/op/clip/clip.go
index c94e1a0b..a8510794 100644
--- a/op/clip/clip.go
+++ b/op/clip/clip.go
@@ -48,6 +48,20 @@ func (p Op) Push(o *op.Ops) Stack {
 func (p Op) add(o *op.Ops) {
 	path := p.path
 
+	if !path.hasSegments && p.width > 0 {
+		if p.path.shape != ops.Rect {
+			panic("only rects have empty paths")
+		}
+		b := frect(path.bounds)
+		var rect Path
+		rect.Begin(o)
+		rect.MoveTo(b.Min)
+		rect.LineTo(f32.Pt(b.Max.X, b.Min.Y))
+		rect.LineTo(b.Max)
+		rect.LineTo(f32.Pt(b.Min.X, b.Max.Y))
+		rect.Close()
+		path = rect.End()
+	}
 	bo := binary.LittleEndian
 	if path.hasSegments {
 		data := ops.Write(&o.Internal, ops.TypePathLen)
@@ -345,3 +359,17 @@ func (o Outline) Op() Op {
 		outline: true,
 	}
 }
+
+// frect converts a rectangle to a f32.Rectangle.
+func frect(r image.Rectangle) f32.Rectangle {
+	return f32.Rectangle{
+		Min: fpt(r.Min), Max: fpt(r.Max),
+	}
+}
+
+// fpt converts an point to a f32.Point.
+func fpt(p image.Point) f32.Point {
+	return f32.Point{
+		X: float32(p.X), Y: float32(p.Y),
+	}
+}