internal/ui: move the error handlings to the ui package

export_test.go

@@ -17,7 +17,3 @@ package ebiten
 var (
 	ImageToBytes = imageToBytes
 )
-
-func PanicOnErrorAtImageAt() {
-	panicOnErrorAtImageAt = true
-}

image.go

@@ -25,10 +25,6 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/ui"
 )
 
-// panicOnErrorAtImageAt indicates whether (*Image).At panics on an error or not.
-// This value is set only on testing.
-var panicOnErrorAtImageAt bool
-
 // Image represents a rectangle set of pixels.
 // The pixel format is alpha-premultiplied RGBA.
 // Image implements image.Image and draw.Image.
@@ -716,24 +712,14 @@ func (i *Image) RGBA64At(x, y int) color.RGBA64 {
 }
 
 func (i *Image) at(x, y int) (r, g, b, a uint8) {
-	// Check the error existence and avoid unnecessary calls.
-	// TODO: The package ui should have an image struct that treats errors correctly.
-	if ui.HasError() {
-		return 0, 0, 0, 0
-	}
-
 	if i.isDisposed() {
 		return 0, 0, 0, 0
 	}
 	if !image.Pt(x, y).In(i.Bounds()) {
 		return 0, 0, 0, 0
 	}
-	pix, err := i.image.Pixels(x, y, 1, 1)
+	pix := i.image.Pixels(x, y, 1, 1)
-	if err != nil {
+	if len(pix) == 0 {
-		if panicOnErrorAtImageAt {
-			panic(err)
-		}
-		ui.SetError(err)
 		return 0, 0, 0, 0
 	}
 	return pix[0], pix[1], pix[2], pix[3]
@@ -747,10 +733,6 @@ func (i *Image) at(x, y int) (r, g, b, a uint8) {
 //
 // If the image is disposed, Set does nothing.
 func (i *Image) Set(x, y int, clr color.Color) {
-	if ui.HasError() {
-		return
-	}
-
 	i.copyCheck()
 	if i.isDisposed() {
 		return
@@ -764,9 +746,7 @@ func (i *Image) Set(x, y int, clr color.Color) {
 
 	r, g, b, a := clr.RGBA()
 	pix := []byte{byte(r >> 8), byte(g >> 8), byte(b >> 8), byte(a >> 8)}
-	if err := i.image.ReplaceSmallRegionPixels(pix, x, y, 1, 1); err != nil {
+	i.image.ReplaceSmallRegionPixels(pix, x, y, 1, 1)
-		ui.SetError(err)
-	}
 }
 
 // Dispose disposes the image data.
@@ -802,10 +782,6 @@ func (i *Image) Dispose() {
 //
 // When the image is disposed, ReplacePixels does nothing.
 func (i *Image) ReplacePixels(pixels []byte) {
-	if ui.HasError() {
-		return
-	}
-
 	i.copyCheck()
 
 	if i.isDisposed() {
@@ -816,9 +792,7 @@ func (i *Image) ReplacePixels(pixels []byte) {
 	// Do not need to copy pixels here.
 	// * In internal/mipmap, pixels are copied when necessary.
 	// * In internal/atlas, pixels are copied to make its paddings.
-	if err := i.image.ReplaceLargeRegionPixels(pixels, r.Min.X, r.Min.Y, r.Dx(), r.Dy()); err != nil {
+	i.image.ReplaceLargeRegionPixels(pixels, r.Min.X, r.Min.Y, r.Dx(), r.Dy())
-		ui.SetError(err)
-	}
 }
 
 // NewImage returns an empty image.

image_test.go

@@ -31,6 +31,7 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/examples/resources/images"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
 	t "github.com/hajimehoshi/ebiten/v2/internal/testing"
+	"github.com/hajimehoshi/ebiten/v2/internal/ui"
 )
 
 // maxImageSize is a maximum image size that should work in almost every environment.
@@ -53,7 +54,7 @@ func skipTooSlowTests(t *testing.T) bool {
 }
 
 func TestMain(m *testing.M) {
-	ebiten.PanicOnErrorAtImageAt()
+	ui.SetPanicOnErrorAtImageAtForTesting(true)
 	t.MainWithRunLoop(m)
 }
 

internal/ui/context.go

@@ -242,14 +242,6 @@ func (g *globalState) setScreenFilterEnabled(enabled bool) {
 	atomic.StoreInt32(&g.screenFilterEnabled_, v)
 }
 
-func HasError() bool {
-	return theGlobalState.error() != nil
-}
-
-func SetError(err error) {
-	theGlobalState.setError(err)
-}
-
 func FPSMode() FPSModeType {
 	return theGlobalState.fpsMode()
 }

internal/ui/image.go

@@ -22,6 +22,14 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/mipmap"
 )
 
+// panicOnErrorAtImageAt indicates whether (*Image).At panics on an error or not.
+// This value is set only on testing.
+var panicOnErrorAtImageAt bool
+
+func SetPanicOnErrorAtImageAtForTesting(value bool) {
+	panicOnErrorAtImageAt = value
+}
+
 type Image struct {
 	mipmap *mipmap.Mipmap
 }
@@ -60,16 +68,39 @@ func (i *Image) DrawTriangles(srcs [graphics.ShaderImageNum]*Image, vertices []f
 	i.mipmap.DrawTriangles(srcMipmaps, vertices, indices, colorm, mode, filter, address, dstRegion, srcRegion, subimageOffsets, s, uniforms, evenOdd, canSkipMipmap)
 }
 
-func (i *Image) ReplaceLargeRegionPixels(pix []byte, x, y, width, height int) error {
+func (i *Image) ReplaceLargeRegionPixels(pix []byte, x, y, width, height int) {
-	return i.mipmap.ReplaceLargeRegionPixels(pix, x, y, width, height)
+	if theGlobalState.error() != nil {
+		return
+	}
+	if err := i.mipmap.ReplaceLargeRegionPixels(pix, x, y, width, height); err != nil {
+		theGlobalState.setError(err)
+	}
 }
 
-func (i *Image) ReplaceSmallRegionPixels(pix []byte, x, y, width, height int) error {
+func (i *Image) ReplaceSmallRegionPixels(pix []byte, x, y, width, height int) {
-	return i.mipmap.ReplaceSmallRegionPixels(graphicsDriver(), pix, x, y, width, height)
+	if theGlobalState.error() != nil {
+		return
+	}
+	if err := i.mipmap.ReplaceSmallRegionPixels(graphicsDriver(), pix, x, y, width, height); err != nil {
+		theGlobalState.setError(err)
+	}
 }
 
-func (i *Image) Pixels(x, y, width, height int) ([]byte, error) {
+func (i *Image) Pixels(x, y, width, height int) []byte {
-	return i.mipmap.Pixels(graphicsDriver(), x, y, width, height)
+	// Check the error existence and avoid unnecessary calls.
+	if theGlobalState.error() != nil {
+		return nil
+	}
+
+	pix, err := i.mipmap.Pixels(graphicsDriver(), x, y, width, height)
+	if err != nil {
+		if panicOnErrorAtImageAt {
+			panic(err)
+		}
+		theGlobalState.setError(err)
+		return nil
+	}
+	return pix
 }
 
 func (i *Image) DumpScreenshot(name string, blackbg bool) error {