From 80c26e6dcce9d9a28cd6dd347a9d75b0cab5d60e Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Tue, 5 Jul 2022 01:13:06 +0900
Subject: [PATCH] ebiten: bug fix: Set after Set resulted in a wrong color

Updates #2154
Updates #2176
---
 image.go      |  2 +-
 image_test.go | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/image.go b/image.go
index 6c34cc35e..256034d24 100644
--- a/image.go
+++ b/image.go
@@ -127,7 +127,7 @@ func (i *Image) resolveSetVerticesCacheIfNeeded() {
 	i.setVerticesCache = nil
 
 	srcs := [graphics.ShaderImageNum]*ui.Image{emptyImage.image}
-	i.image.DrawTriangles(srcs, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeSourceOver, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, i.adjustedRegion(), graphicsdriver.Region{}, [graphics.ShaderImageNum - 1][2]float32{}, nil, nil, false, true)
+	i.image.DrawTriangles(srcs, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeCopy, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, i.adjustedRegion(), graphicsdriver.Region{}, [graphics.ShaderImageNum - 1][2]float32{}, nil, nil, false, true)
 }
 
 // Size returns the size of the image.
diff --git a/image_test.go b/image_test.go
index 7483a8fbf..e57b680fa 100644
--- a/image_test.go
+++ b/image_test.go
@@ -3350,3 +3350,29 @@ func TestImageTooManyDrawTriangles(t *testing.T) {
 		}
 	}
 }
+
+func TestImageSetOverSet(t *testing.T) {
+	img := ebiten.NewImage(1, 1)
+	img.Set(0, 0, color.RGBA{0xff, 0xff, 0xff, 0xff})
+	if got, want := img.At(0, 0), (color.RGBA{0xff, 0xff, 0xff, 0xff}); got != want {
+		t.Errorf("got: %v, want: %v", got, want)
+	}
+
+	// Apply the change by 'Set' by calling DrawImage.
+	dummy := ebiten.NewImage(1, 1)
+	img.DrawImage(dummy, nil)
+	if got, want := img.At(0, 0), (color.RGBA{0xff, 0xff, 0xff, 0xff}); got != want {
+		t.Errorf("got: %v, want: %v", got, want)
+	}
+
+	img.Set(0, 0, color.RGBA{0x80, 0x80, 0x80, 0x80})
+	if got, want := img.At(0, 0), (color.RGBA{0x80, 0x80, 0x80, 0x80}); got != want {
+		t.Errorf("got: %v, want: %v", got, want)
+	}
+
+	// Apply the change by 'Set' again.
+	img.DrawImage(dummy, nil)
+	if got, want := img.At(0, 0), (color.RGBA{0x80, 0x80, 0x80, 0x80}); got != want {
+		t.Errorf("got: %v, want: %v", got, want)
+	}
+}