From 77709d17711d0d1704383065e7dfc3867e777b6a Mon Sep 17 00:00:00 2001
From: Elias Naur <mail@eliasnaur.com>
Date: Tue, 18 Feb 2025 14:51:26 +0000
Subject: [PATCH] gpu: don't store transformed rectangle paths under the same
 cache key

Fixes incorrect rendering of multiple transformed instances of a
rectangle.

Fixes: https://todo.sr.ht/~eliasnaur/gio/635
Signed-off-by: Elias Naur <mail@eliasnaur.com>
---
 gpu/gpu.go                                     |   3 ++-
 gpu/internal/rendertest/clip_test.go           |  17 +++++++++++++++++
 .../rendertest/refs/TestInstancedRects.png     | Bin 0 -> 787 bytes
 3 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 gpu/internal/rendertest/refs/TestInstancedRects.png

diff --git a/gpu/gpu.go b/gpu/gpu.go
index b68ca541..49c878ea 100644
--- a/gpu/gpu.go
+++ b/gpu/gpu.go
@@ -1055,6 +1055,7 @@ loop:
 			} else {
 				quads.aux, bounds, _ = d.boundsForTransformedRect(bounds, trans)
 				quads.key = opKey{Key: encOp.Key}
+				quads.key = quads.key.SetTransform(trans)
 			}
 			d.addClipPath(&state, quads.aux, quads.key, bounds, off)
 			quads = quadsOp{}
@@ -1100,7 +1101,7 @@ loop:
 				// The paint operation is sheared or rotated, add a clip path representing
 				// this transformed rectangle.
 				k := opKey{Key: encOp.Key}
-				k.SetTransform(t) // TODO: This call has no effect.
+				k = k.SetTransform(t)
 				d.addClipPath(&state, clipData, k, bnd, off)
 			}
 
diff --git a/gpu/internal/rendertest/clip_test.go b/gpu/internal/rendertest/clip_test.go
index 793b1397..381e9784 100644
--- a/gpu/internal/rendertest/clip_test.go
+++ b/gpu/internal/rendertest/clip_test.go
@@ -293,3 +293,20 @@ func TestStrokedRect(t *testing.T) {
 	}, func(r result) {
 	})
 }
+
+func TestInstancedRects(t *testing.T) {
+	run(t, func(o *op.Ops) {
+		macro := op.Record(o)
+		clip := clip.Rect{Max: image.Pt(20, 20)}.Push(o)
+		paint.ColorOp{Color: color.NRGBA{R: 0x80, A: 0xFF}}.Add(o)
+		paint.PaintOp{}.Add(o)
+		clip.Pop()
+		c := macro.Stop()
+
+		for i := 0; i < 2; i++ {
+			op.Affine(f32.Affine2D{}.Rotate(f32.Pt(0, 0), .2)).Add(o)
+			c.Add(o)
+			op.Offset(image.Pt(20, 20)).Add(o)
+		}
+	}, nil)
+}
diff --git a/gpu/internal/rendertest/refs/TestInstancedRects.png b/gpu/internal/rendertest/refs/TestInstancedRects.png
new file mode 100644
index 0000000000000000000000000000000000000000..e5f195a8b36aa5eee87ed70e5495cdf70533bbd3
GIT binary patch
literal 787
zcmeAS@N?(olHy`uVBq!ia0vp^4Is?H1|$#LC7xzrV7le$;uunK>+S9P+5Uwx$3H%w
zBL6egOfhxqr^l0Gc1-AQUDL+xwWHu^+w8j+!fu@V{ic1&qS(jBSh?3~Y$|fqi_sAe
z^3pJMH8GzYe>)~;>6czp>#d*v+Q^swYrOvZtL5|0md}5yCTKh;b8vSkKHxQ_ui+!t
z_1g{qWc*Suhy<huWr{Ai^wsKtn?p34^{vF2FPDZk*stH%FrD!_vmc8|*+C&;-{lNb
z*YOGa?q)cvHmi)$#!)4vVf(U~WsJXkjo&iOF+1DBJ;8Bu=CWG$h`d=Z#UAu}E{koL
ztp-$Z%g5*~(;JhMCENyLb&@{281#J&-!grfnRJWQBD3qMo`YP0`GdbE+!r#st_HXL
zYN%zjWn`AD`E&e(yLIBqlc5`Vq?q_v=5SXC7|86u|9`*1!XqWlz6WkKI5Vzg)b>%m
z>wfHT!+Ob>vkBduDocdT!fpuLa9T_{TqC^d-_`n;`m+yzXS9`EW4Q8_OkM7Q6C!;b
z_C`BIFWg`<RSUOewXp2{&U&7yuk@gju+DeQ1iu5TXZ)Le_@Rtm+J<u`r+5DPe&kGz
zlN|33@eRABpUudr<SMXF`*vRCF=O*P!Bd8Rz8Ze~TfdC^LiVnw8V>o4hvm6%B<$K8
z!`EH>BgTP|&1bvJ>i-o$Vg4K0K;hFz*cUu!<@x`W)t_N$#NXT8QGfr<TA{-FLO<b$
zGUL`|*1y~1<v(n0V2UxjTlD7Nd9jk;_fvrS*mXF51RVGvKQoWh=ii^~@B?#m9^L)x
zBl=*$%W3ZeF9;OaJ-A%YSHD8|*{lrDt%naaEN1jy9@%h4WcBlP8*~@wKlm-u{(miZ
z*vy!(vZCS71sLD|3v9?<7JBsDfju&O=^u6kF&5p(@_Knk)Qmlb^M_GngJZDgW{y(E
mwUTelc|9kokcpmt<bKXGLqagv)(e=}89ZJ6T-G@yGywo4*<hal

literal 0
HcmV?d00001