all: avoid unneeded heap allocations, especially since embedded display value is interface anyhow

deadprogram · deadprogram · commit 05eb156cff8b · 2023-04-27T19:48:29.000+02:00
Signed-off-by: deadprogram &lt;ron@hybridgroup.com&gt;
diff --git a/concrete.go b/concrete.go
@@ -53,8 +53,8 @@ func (glyph Glyph) Draw(display drivers.Displayer, x int16, y int16, color color
 }
 
 // Info returns glyph information.
-func (glyph Glyph) Info() *GlyphInfo {
-	return &GlyphInfo{
+func (glyph Glyph) Info() GlyphInfo {
+	return GlyphInfo{
 		Rune:     glyph.Rune,
 		Width:    glyph.Width,
 		Height:   glyph.Height,
@@ -69,8 +69,10 @@ func (f *Font) GetYAdvance() uint8 {
 	return f.YAdvance
 }
 
+var emptyBitmap [1]byte
+
 // GetGlyph returns the glyph corresponding to the specified rune in the font.
-func (font *Font) GetGlyph(r rune) Glypher {
+func (font *Font) GetGlyph(r rune) Glyph {
 	s := 0
 	e := len(font.Glyphs) - 1
 
@@ -92,7 +94,7 @@ func (font *Font) GetGlyph(r rune) Glypher {
 			XAdvance: font.Glyphs[0].Info().XAdvance,
 			XOffset:  font.Glyphs[0].Info().XOffset,
 			YOffset:  font.Glyphs[0].Info().YOffset,
-			Bitmaps:  []byte{0},
+			Bitmaps:  emptyBitmap[:],
 		}
 		return g
 	}
diff --git a/const2bit/const2bit.go b/const2bit/const2bit.go
@@ -65,8 +65,8 @@ func (glyph Glyph) Draw(display drivers.Displayer, x int16, y int16, c color.RGB
 }
 
 // Info returns glyph information.
-func (glyph Glyph) Info() *tinyfont.GlyphInfo {
-	return &tinyfont.GlyphInfo{
+func (glyph Glyph) Info() tinyfont.GlyphInfo {
+	return tinyfont.GlyphInfo{
 		Rune:     glyph.Rune,
 		Width:    glyph.Width,
 		Height:   glyph.Height,
diff --git a/display.go b/display.go
@@ -13,16 +13,16 @@ type RotatedDisplay struct {
 	Y        int16
 }
 
-func NewRotatedDisplay(display drivers.Displayer, rotation Rotation, x, y int16) *RotatedDisplay {
-	return &RotatedDisplay{
+func NewRotatedDisplay(display drivers.Displayer, rotation Rotation, x, y int16) RotatedDisplay {
+	return RotatedDisplay{
 		display:  display,
 		Rotation: rotation,
 		X:        x,
 		Y:        y,
 	}
 }
 
-func (d *RotatedDisplay) Size() (int16, int16) {
+func (d RotatedDisplay) Size() (int16, int16) {
 	x, y := d.display.Size()
 	if d.Rotation == NO_ROTATION {
 		return x, y
@@ -35,7 +35,7 @@ func (d *RotatedDisplay) Size() (int16, int16) {
 	}
 }
 
-func (d *RotatedDisplay) SetPixel(x, y int16, c color.RGBA) {
+func (d RotatedDisplay) SetPixel(x, y int16, c color.RGBA) {
 	if d.Rotation == NO_ROTATION {
 		d.display.SetPixel(d.X+x, d.Y+y, c)
 	} else if d.Rotation == ROTATION_90 {
@@ -47,6 +47,6 @@ func (d *RotatedDisplay) SetPixel(x, y int16, c color.RGBA) {
 	}
 }
 
-func (d *RotatedDisplay) Display() error {
+func (d RotatedDisplay) Display() error {
 	return d.display.Display()
 }
diff --git a/tinyfont.go b/tinyfont.go
@@ -30,14 +30,14 @@ type GlyphInfo struct {
 
 // Fonter is an interface that represents a set of glyphs.
 type Fonter interface {
-	GetGlyph(r rune) Glypher
+	GetGlyph(r rune) Glyph
 	GetYAdvance() uint8
 }
 
 // Glypher is glyph itself, and it knows how to draw itself.
 type Glypher interface {
 	Draw(display drivers.Displayer, x int16, y int16, color color.RGBA)
-	Info() *GlyphInfo
+	Info() GlyphInfo
 }
 
 // DrawChar sets a single rune in the buffer of the display.
@@ -123,6 +123,6 @@ func LineWidth(f Fonter, str string) (innerWidth uint32, outboxWidth uint32) {
 }
 
 // GetGlyph returns the glyph corresponding to the specified rune in the font.
-func GetGlyph(f Fonter, r rune) Glypher {
+func GetGlyph(f Fonter, r rune) Glyph {
 	return f.GetGlyph(r)
 }

Original file line number	Diff line number	Diff line change
`@@ -13,16 +13,16 @@ type RotatedDisplay struct {`
`13`	`13`	`Y int16`
`14`	`14`	`}`
`15`	`15`
`16`		`-func NewRotatedDisplay(display drivers.Displayer, rotation Rotation, x, y int16) *RotatedDisplay {`
`17`		`- return &RotatedDisplay{`
	`16`	`+func NewRotatedDisplay(display drivers.Displayer, rotation Rotation, x, y int16) RotatedDisplay {`
	`17`	`+ return RotatedDisplay{`
`18`	`18`	`display: display,`
`19`	`19`	`Rotation: rotation,`
`20`	`20`	`X: x,`
`21`	`21`	`Y: y,`
`22`	`22`	`}`
`23`	`23`	`}`
`24`	`24`
`25`		`-func (d *RotatedDisplay) Size() (int16, int16) {`
	`25`	`+func (d RotatedDisplay) Size() (int16, int16) {`
`26`	`26`	`x, y := d.display.Size()`
`27`	`27`	`if d.Rotation == NO_ROTATION {`
`28`	`28`	`return x, y`
`@@ -35,7 +35,7 @@ func (d *RotatedDisplay) Size() (int16, int16) {`
`35`	`35`	`}`
`36`	`36`	`}`
`37`	`37`
`38`		`-func (d *RotatedDisplay) SetPixel(x, y int16, c color.RGBA) {`
	`38`	`+func (d RotatedDisplay) SetPixel(x, y int16, c color.RGBA) {`
`39`	`39`	`if d.Rotation == NO_ROTATION {`
`40`	`40`	`d.display.SetPixel(d.X+x, d.Y+y, c)`
`41`	`41`	`} else if d.Rotation == ROTATION_90 {`
`@@ -47,6 +47,6 @@ func (d *RotatedDisplay) SetPixel(x, y int16, c color.RGBA) {`
`47`	`47`	`}`
`48`	`48`	`}`
`49`	`49`
`50`		`-func (d *RotatedDisplay) Display() error {`
	`50`	`+func (d RotatedDisplay) Display() error {`
`51`	`51`	`return d.display.Display()`
`52`	`52`	`}`
Original file line number	Diff line number	Diff line change
`@@ -30,14 +30,14 @@ type GlyphInfo struct {`
`30`	`30`
`31`	`31`	`// Fonter is an interface that represents a set of glyphs.`
`32`	`32`	`type Fonter interface {`
`33`		`- GetGlyph(r rune) Glypher`
	`33`	`+ GetGlyph(r rune) Glyph`
`34`	`34`	`GetYAdvance() uint8`
`35`	`35`	`}`
`36`	`36`
`37`	`37`	`// Glypher is glyph itself, and it knows how to draw itself.`
`38`	`38`	`type Glypher interface {`
`39`	`39`	`Draw(display drivers.Displayer, x int16, y int16, color color.RGBA)`
`40`		`- Info() *GlyphInfo`
	`40`	`+ Info() GlyphInfo`
`41`	`41`	`}`
`42`	`42`
`43`	`43`	`// DrawChar sets a single rune in the buffer of the display.`
`@@ -123,6 +123,6 @@ func LineWidth(f Fonter, str string) (innerWidth uint32, outboxWidth uint32) {`
`123`	`123`	`}`
`124`	`124`
`125`	`125`	`// GetGlyph returns the glyph corresponding to the specified rune in the font.`
`126`		`-func GetGlyph(f Fonter, r rune) Glypher {`
	`126`	`+func GetGlyph(f Fonter, r rune) Glyph {`
`127`	`127`	`return f.GetGlyph(r)`
`128`	`128`	`}`