all: clean up code, upgrade to modern Go

Signed-off-by: ddkwork

Author: ddkwork

app/gl_macos.go

@@ -8,7 +8,6 @@ package app
 import (
 	"errors"
 	"runtime"
-
 	"unsafe"
 
 	"gioui.org/gpu"

app/os_darwin.go

@@ -40,6 +40,7 @@ static CFTypeRef newNSString(unichar *chars, NSUInteger length) {
 }
 */
 import "C"
+
 import (
 	"errors"
 	"sync"

app/os_x11.go

@@ -26,6 +26,7 @@ package app
 
 */
 import "C"
+
 import (
 	"errors"
 	"fmt"
@@ -751,9 +752,7 @@ func (h *x11EventHandler) handleEvents() bool {
 	return redraw
 }
 
-var (
-	x11Threads sync.Once
-)
+var x11Threads sync.Once
 
 func init() {
 	x11Driver = newX11Window

app/window.go

@@ -444,10 +444,7 @@ func (c *callbacks) SetComposingRegion(r key.Range) {
 func (c *callbacks) EditorInsert(text string) {
 	sel := c.w.imeState.Selection.Range
 	c.EditorReplace(sel, text)
-	start := sel.Start
-	if sel.End < start {
-		start = sel.End
-	}
+	start := min(sel.End, sel.Start)
 	sel.Start = start + utf8.RuneCountInString(text)
 	sel.End = sel.Start
 	c.SetEditorSelection(sel)

f32/affine_test.go

@@ -201,7 +201,7 @@ func BenchmarkTransformOffset(b *testing.B) {
 	o := Point{X: 0.5, Y: 0.5}
 	aff := Affine2D{}.Offset(o)
 
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		p = aff.Transform(p)
 	}
 	_ = p
@@ -211,7 +211,7 @@ func BenchmarkTransformScale(b *testing.B) {
 	p := Point{X: 1, Y: 2}
 	s := Point{X: 0.5, Y: 0.5}
 	aff := Affine2D{}.Scale(Point{}, s)
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		p = aff.Transform(p)
 	}
 	_ = p
@@ -221,7 +221,7 @@ func BenchmarkTransformRotate(b *testing.B) {
 	p := Point{X: 1, Y: 2}
 	a := float32(math.Pi / 2)
 	aff := Affine2D{}.Rotate(Point{}, a)
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		p = aff.Transform(p)
 	}
 	_ = p
@@ -231,7 +231,7 @@ func BenchmarkTransformTranslateMultiply(b *testing.B) {
 	a := Affine2D{}.Offset(Point{X: 1, Y: 1}).Rotate(Point{}, math.Pi/3)
 	t := Affine2D{}.Offset(Point{X: 0.5, Y: 0.5})
 
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		a = a.Mul(t)
 	}
 }
@@ -240,7 +240,7 @@ func BenchmarkTransformScaleMultiply(b *testing.B) {
 	a := Affine2D{}.Offset(Point{X: 1, Y: 1}).Rotate(Point{}, math.Pi/3)
 	t := Affine2D{}.Offset(Point{X: 0.5, Y: 0.5}).Scale(Point{}, Point{X: 0.4, Y: -0.5})
 
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		a = a.Mul(t)
 	}
 }
@@ -249,7 +249,7 @@ func BenchmarkTransformMultiply(b *testing.B) {
 	a := Affine2D{}.Offset(Point{X: 1, Y: 1}).Rotate(Point{}, math.Pi/3)
 	t := Affine2D{}.Offset(Point{X: 0.5, Y: 0.5}).Rotate(Point{}, math.Pi/7)
 
-	for i := 0; i < b.N; i++ {
+	for b.Loop() {
 		a = a.Mul(t)
 	}
 }

gpu/clip_test.go

@@ -10,7 +10,7 @@ import (
 
 func BenchmarkEncodeQuadTo(b *testing.B) {
 	var data [vertStride * 4]byte
-	for i := 0; i < b.N; i++ {
+	for i := 0; b.Loop(); i++ {
 		v := float32(i)
 		encodeQuadTo(data[:], 123,
 			f32.Point{X: v, Y: v},

gpu/gpu.go

@@ -15,6 +15,7 @@ import (
 	"image/color"
 	"math"
 	"reflect"
+	"slices"
 	"time"
 	"unsafe"
 
@@ -189,7 +190,7 @@ const (
 // imageOpData is the shadow of paint.ImageOp.
 type imageOpData struct {
 	src    *image.RGBA
-	handle interface{}
+	handle any
 	filter byte
 }
 
@@ -200,7 +201,7 @@ type linearGradientOpData struct {
 	color2 color.NRGBA
 }
 
-func decodeImageOp(data []byte, refs []interface{}) imageOpData {
+func decodeImageOp(data []byte, refs []any) imageOpData {
 	handle := refs[1]
 	if handle == nil {
 		return imageOpData{}
@@ -547,7 +548,7 @@ func newBlitter(ctx driver.Device) *blitter {
 	b.texUniforms = new(blitTexUniforms)
 	b.linearGradientUniforms = new(blitLinearGradientUniforms)
 	pipelines, err := createColorPrograms(ctx, gio.Shader_blit_vert, gio.Shader_blit_frag,
-		[3]interface{}{b.colUniforms, b.linearGradientUniforms, b.texUniforms},
+		[3]any{b.colUniforms, b.linearGradientUniforms, b.texUniforms},
 	)
 	if err != nil {
 		panic(err)
@@ -565,7 +566,7 @@ func (b *blitter) release() {
 	}
 }
 
-func createColorPrograms(b driver.Device, vsSrc shader.Sources, fsSrc [3]shader.Sources, uniforms [3]interface{}) (pipelines [2][3]*pipeline, err error) {
+func createColorPrograms(b driver.Device, vsSrc shader.Sources, fsSrc [3]shader.Sources, uniforms [3]any) (pipelines [2][3]*pipeline, err error) {
 	defer func() {
 		if err != nil {
 			for _, p := range pipelines {
@@ -822,7 +823,7 @@ func (r *renderer) packLayers(layers []opacityLayer) []opacityLayer {
 			layers[l.parent].clip = b.Union(l.clip)
 		}
 		if l.clip.Empty() {
-			layers = append(layers[:i], layers[i+1:]...)
+			layers = slices.Delete(layers, i, i+1)
 		}
 	}
 	// Pack layers.
@@ -1316,7 +1317,7 @@ func (b *blitter) blit(mat materialType, fbo bool, col f32color.RGBA, col1, col2
 
 // newUniformBuffer creates a new GPU uniform buffer backed by the
 // structure uniformBlock points to.
-func newUniformBuffer(b driver.Device, uniformBlock interface{}) *uniformBuffer {
+func newUniformBuffer(b driver.Device, uniformBlock any) *uniformBuffer {
 	ref := reflect.ValueOf(uniformBlock)
 	// Determine the size of the uniforms structure, *uniforms.
 	size := ref.Elem().Type().Size()

gpu/headless/driver_test.go

@@ -21,8 +21,10 @@ import (
 
 var dumpImages = flag.Bool("saveimages", false, "save test images")
 
-var clearCol = color.NRGBA{A: 0xff, R: 0xde, G: 0xad, B: 0xbe}
-var clearColExpect = f32color.NRGBAToRGBA(clearCol)
+var (
+	clearCol       = color.NRGBA{A: 0xff, R: 0xde, G: 0xad, B: 0xbe}
+	clearColExpect = f32color.NRGBAToRGBA(clearCol)
+)
 
 func TestFramebufferClear(t *testing.T) {
 	b := newDriver(t)
@@ -202,5 +204,5 @@ func saveImage(file string, img image.Image) error {
 	if err := png.Encode(&buf, img); err != nil {
 		return err
 	}
-	return os.WriteFile(file, buf.Bytes(), 0666)
+	return os.WriteFile(file, buf.Bytes(), 0o666)
 }

gpu/internal/d3d11/d3d11_windows.go

@@ -152,9 +152,7 @@ func newDirect3D11Device(api driver.Direct3D11) (driver.Device, error) {
 }
 
 func (b *Backend) BeginFrame(target driver.RenderTarget, clear bool, viewport image.Point) driver.Texture {
-	var (
-		renderTarget *d3d11.RenderTargetView
-	)
+	var renderTarget *d3d11.RenderTargetView
 	if target != nil {
 		switch t := target.(type) {
 		case driver.Direct3D11RenderTarget:
@@ -229,10 +227,7 @@ func (b *Backend) NewTexture(format driver.TextureFormat, width, height int, min
 		// Flags required by ID3D11DeviceContext::GenerateMips.
 		bindFlags |= d3d11.BIND_SHADER_RESOURCE | d3d11.BIND_RENDER_TARGET
 		miscFlags |= d3d11.RESOURCE_MISC_GENERATE_MIPS
-		dim := width
-		if height > dim {
-			dim = height
-		}
+		dim := max(height, width)
 		log2 := 32 - bits.LeadingZeros32(uint32(dim)) - 1
 		nmipmaps = log2 + 1
 	}
@@ -802,7 +797,7 @@ func (t *Texture) ReadPixels(src image.Rectangle, pixels []byte, stride int) err
 	mapSize := dstPitch * h
 	data := sliceOf(resMap.PData, mapSize)
 	width := w * 4
-	for r := 0; r < h; r++ {
+	for r := range h {
 		pixels := pixels[r*srcPitch:]
 		copy(pixels[:width], data[r*dstPitch:])
 	}

gpu/internal/driver/driver.go

@@ -96,8 +96,10 @@ type BlendFactor uint8
 
 type Topology uint8
 
-type TextureFilter uint8
-type TextureFormat uint8
+type (
+	TextureFilter uint8
+	TextureFormat uint8
+)
 
 type BufferBinding uint8
 
@@ -217,7 +219,7 @@ func flipImageY(stride, height int, pixels []byte) {
 	// Flip image in y-direction. OpenGL's origin is in the lower
 	// left corner.
 	row := make([]uint8, stride)
-	for y := 0; y < height/2; y++ {
+	for y := range height / 2 {
 		y1 := height - y - 1
 		dest := y1 * stride
 		src := y * stride