internal/ui: replace deprecated APIs

[UIScreen mainScreen] is now deprecated.

image.go

@@ -554,30 +554,32 @@ func (i *Image) DrawTriangles(vertices []Vertex, indices []uint16, img *Image, o
 	vs := i.ensureTmpVertices(len(vertices) * graphics.VertexFloatCount)
 	dst := i
 	if options.ColorScaleMode == ColorScaleModeStraightAlpha {
-		for i, v := range vertices {
-			dx, dy := dst.adjustPositionF32(v.DstX, v.DstY)
+		// Avoid using `for i, v := range vertices` as adding `v` creates a copy from `vertices` unnecessarily on each loop (#3103).
+		for i := range vertices {
+			dx, dy := dst.adjustPositionF32(vertices[i].DstX, vertices[i].DstY)
 			vs[i*graphics.VertexFloatCount] = dx
 			vs[i*graphics.VertexFloatCount+1] = dy
-			sx, sy := img.adjustPositionF32(v.SrcX, v.SrcY)
+			sx, sy := img.adjustPositionF32(vertices[i].SrcX, vertices[i].SrcY)
 			vs[i*graphics.VertexFloatCount+2] = sx
 			vs[i*graphics.VertexFloatCount+3] = sy
-			vs[i*graphics.VertexFloatCount+4] = v.ColorR * v.ColorA * cr
-			vs[i*graphics.VertexFloatCount+5] = v.ColorG * v.ColorA * cg
-			vs[i*graphics.VertexFloatCount+6] = v.ColorB * v.ColorA * cb
-			vs[i*graphics.VertexFloatCount+7] = v.ColorA * ca
+			vs[i*graphics.VertexFloatCount+4] = vertices[i].ColorR * vertices[i].ColorA * cr
+			vs[i*graphics.VertexFloatCount+5] = vertices[i].ColorG * vertices[i].ColorA * cg
+			vs[i*graphics.VertexFloatCount+6] = vertices[i].ColorB * vertices[i].ColorA * cb
+			vs[i*graphics.VertexFloatCount+7] = vertices[i].ColorA * ca
 		}
 	} else {
-		for i, v := range vertices {
-			dx, dy := dst.adjustPositionF32(v.DstX, v.DstY)
+		// See comment above (#3103).
+		for i := range vertices {
+			dx, dy := dst.adjustPositionF32(vertices[i].DstX, vertices[i].DstY)
 			vs[i*graphics.VertexFloatCount] = dx
 			vs[i*graphics.VertexFloatCount+1] = dy
-			sx, sy := img.adjustPositionF32(v.SrcX, v.SrcY)
+			sx, sy := img.adjustPositionF32(vertices[i].SrcX, vertices[i].SrcY)
 			vs[i*graphics.VertexFloatCount+2] = sx
 			vs[i*graphics.VertexFloatCount+3] = sy
-			vs[i*graphics.VertexFloatCount+4] = v.ColorR * cr
-			vs[i*graphics.VertexFloatCount+5] = v.ColorG * cg
-			vs[i*graphics.VertexFloatCount+6] = v.ColorB * cb
-			vs[i*graphics.VertexFloatCount+7] = v.ColorA * ca
+			vs[i*graphics.VertexFloatCount+4] = vertices[i].ColorR * cr
+			vs[i*graphics.VertexFloatCount+5] = vertices[i].ColorG * cg
+			vs[i*graphics.VertexFloatCount+6] = vertices[i].ColorB * cb
+			vs[i*graphics.VertexFloatCount+7] = vertices[i].ColorA * ca
 		}
 	}
 	is := i.ensureTmpIndices(len(indices))
@@ -718,24 +720,25 @@ func (i *Image) DrawTrianglesShader(vertices []Vertex, indices []uint16, shader
 	vs := i.ensureTmpVertices(len(vertices) * graphics.VertexFloatCount)
 	dst := i
 	src := options.Images[0]
-	for i, v := range vertices {
-		dx, dy := dst.adjustPositionF32(v.DstX, v.DstY)
+	// Avoid using `for i, v := range vertices` as adding `v` creates a copy from `vertices` unnecessarily on each loop (#3103).
+	for i := range vertices {
+		dx, dy := dst.adjustPositionF32(vertices[i].DstX, vertices[i].DstY)
 		vs[i*graphics.VertexFloatCount] = dx
 		vs[i*graphics.VertexFloatCount+1] = dy
-		sx, sy := v.SrcX, v.SrcY
+		sx, sy := vertices[i].SrcX, vertices[i].SrcY
 		if src != nil {
 			sx, sy = src.adjustPositionF32(sx, sy)
 		}
 		vs[i*graphics.VertexFloatCount+2] = sx
 		vs[i*graphics.VertexFloatCount+3] = sy
-		vs[i*graphics.VertexFloatCount+4] = v.ColorR
-		vs[i*graphics.VertexFloatCount+5] = v.ColorG
-		vs[i*graphics.VertexFloatCount+6] = v.ColorB
-		vs[i*graphics.VertexFloatCount+7] = v.ColorA
-		vs[i*graphics.VertexFloatCount+8] = v.Custom0
-		vs[i*graphics.VertexFloatCount+9] = v.Custom1
-		vs[i*graphics.VertexFloatCount+10] = v.Custom2
-		vs[i*graphics.VertexFloatCount+11] = v.Custom3
+		vs[i*graphics.VertexFloatCount+4] = vertices[i].ColorR
+		vs[i*graphics.VertexFloatCount+5] = vertices[i].ColorG
+		vs[i*graphics.VertexFloatCount+6] = vertices[i].ColorB
+		vs[i*graphics.VertexFloatCount+7] = vertices[i].ColorA
+		vs[i*graphics.VertexFloatCount+8] = vertices[i].Custom0
+		vs[i*graphics.VertexFloatCount+9] = vertices[i].Custom1
+		vs[i*graphics.VertexFloatCount+10] = vertices[i].Custom2
+		vs[i*graphics.VertexFloatCount+11] = vertices[i].Custom3
 	}
 
 	is := i.ensureTmpIndices(len(indices))

internal/ui/ui_android.go

@@ -119,7 +119,7 @@ func (*graphicsDriverCreatorImpl) newPlayStation5() (graphicsdriver.Graphics, er
 	return nil, errors.New("ui: PlayStation 5 is not supported in this environment")
 }
 
-func deviceScaleFactorImpl() float64 {
+func (u *UserInterface) deviceScaleFactor() float64 {
 	var s float64
 	if err := app.RunOnJVM(func(vm, env, ctx uintptr) error {
 		// TODO: This might be crash when this is called from init(). How can we detect this?

internal/ui/ui_ios.go

@@ -19,8 +19,31 @@ package ui
 //
 // #import <UIKit/UIKit.h>
 //
-// static double devicePixelRatio() {
-//   return [[UIScreen mainScreen] nativeScale];
+// static double devicePixelRatioOnMainThread(UIView* view) {
+//   UIWindow* window = view.window;
+//   if (!window) {
+//     return 1;
+//   }
+//   UIWindowScene* scene = window.windowScene;
+//   if (!scene) {
+//     return 1;
+//   }
+//   return scene.screen.nativeScale;
+// }
+//
+// static double devicePixelRatio(uintptr_t viewPtr) {
+//   if (!viewPtr) {
+//     return 1;
+//   }
+//   UIView* view = (__bridge UIView*)(void*)viewPtr;
+//   if ([NSThread isMainThread]) {
+//     return devicePixelRatioOnMainThread(view);
+//   }
+//   __block double scale;
+//   dispatch_sync(dispatch_get_main_queue(), ^{
+//     scale = devicePixelRatioOnMainThread(view);
+//   });
+//   return scale;
 // }
 import "C"
 
@@ -66,6 +89,7 @@ func (*graphicsDriverCreatorImpl) newPlayStation5() (graphicsdriver.Graphics, er
 }
 
 func (u *UserInterface) SetUIView(uiview uintptr) error {
+	u.uiView.Store(uiview)
 	select {
 	case err := <-u.errCh:
 		return err
@@ -89,9 +113,8 @@ func (u *UserInterface) IsGL() (bool, error) {
 	return u.GraphicsLibrary() == GraphicsLibraryOpenGL, nil
 }
 
-func deviceScaleFactorImpl() float64 {
-	// TODO: Can this be called from non-main threads?
-	return float64(C.devicePixelRatio())
+func (u *UserInterface) deviceScaleFactor() float64 {
+	return float64(C.devicePixelRatio(C.uintptr_t(u.uiView.Load())))
 }
 
 func dipToNativePixels(x float64, scale float64) float64 {

internal/ui/ui_mobile.go

@@ -104,6 +104,9 @@ type userInterfaceImpl struct {
 	strictContextRestoration     atomic.Bool
 	strictContextRestorationOnce sync.Once
 
+	// uiView is used only on iOS.
+	uiView atomic.Uintptr
+
 	m sync.RWMutex
 }
 
@@ -285,7 +288,7 @@ func (m *Monitor) DeviceScaleFactor() float64 {
 	// Initialize this lazily.
 	m.deviceScaleFactorOnce.Do(func() {
 		// Assume that the device scale factor never changes on mobiles.
-		m.deviceScaleFactor = deviceScaleFactorImpl()
+		m.deviceScaleFactor = theUI.deviceScaleFactor()
 	})
 	return m.deviceScaleFactor
 }