Add example/internal and move font rendering into it

_docs/public/example/images/license.md

@@ -1,6 +1,6 @@
 # License
 
-## blocks/font.png
+## arcadefont.png
 
 ```
 9031 Font ReadMe

example/blocks/blocks/font.go

@@ -16,98 +16,18 @@ package blocks
 
 import (
 	"github.com/hajimehoshi/ebiten"
-	"github.com/hajimehoshi/ebiten/ebitenutil"
+	"github.com/hajimehoshi/ebiten/example/internal"
 	"image/color"
-	"math"
-	"strings"
 )
 
-var imageFont *ebiten.Image
-
-func init() {
-	var err error
-	imageFont, _, err = ebitenutil.NewImageFromFile("images/blocks/font.png", ebiten.FilterNearest)
-	if err != nil {
-		panic(err)
-	}
-}
-
-const charWidth = 8
-const charHeight = 8
-
-func textWidth(str string) int {
-	// TODO: Take care about '\n'
-	return charWidth * len(str)
-}
-
-type fontImageParts string
-
-func (f fontImageParts) Len() int {
-	return len(f)
-}
-
-func (f fontImageParts) Dst(i int) (x0, y0, x1, y1 int) {
-	x := i - strings.LastIndex(string(f)[:i], "\n") - 1
-	y := strings.Count(string(f)[:i], "\n")
-	x *= charWidth
-	y *= charHeight
-	if x < 0 {
-		return 0, 0, 0, 0
-	}
-	return x, y, x + charWidth, y + charHeight
-}
-
-func (f fontImageParts) Src(i int) (x0, y0, x1, y1 int) {
-	code := int(f[i])
-	if code == '\n' {
-		return 0, 0, 0, 0
-	}
-	x := (code % 16) * charWidth
-	y := ((code - 32) / 16) * charHeight
-	return x, y, x + charWidth, y + charHeight
-}
-
-func drawText(rt *ebiten.Image, str string, ox, oy, scale int, c color.Color) error {
-	options := &ebiten.DrawImageOptions{
-		ImageParts: fontImageParts(str),
-	}
-	options.GeoM.Scale(float64(scale), float64(scale))
-	options.GeoM.Translate(float64(ox), float64(oy))
-
-	ur, ug, ub, ua := c.RGBA()
-	const max = math.MaxUint16
-	r := float64(ur) / max
-	g := float64(ug) / max
-	b := float64(ub) / max
-	a := float64(ua) / max
-	if 0 < a {
-		r /= a
-		g /= a
-		b /= a
-	}
-	options.ColorM.Scale(r, g, b, a)
-
-	return rt.DrawImage(imageFont, options)
-}
-
-func drawTextWithShadow(rt *ebiten.Image, str string, x, y, scale int, clr color.Color) error {
-	if err := drawText(rt, str, x+1, y+1, scale, color.NRGBA{0, 0, 0, 0x80}); err != nil {
-		return err
-	}
-	if err := drawText(rt, str, x, y, scale, clr); err != nil {
-		return err
-	}
-	return nil
-}
-
 func drawTextWithShadowCenter(rt *ebiten.Image, str string, x, y, scale int, clr color.Color, width int) error {
-	w := textWidth(str) * scale
+	w := internal.ArcadeFont.TextWidth(str) * scale
 	x += (width - w) / 2
-	return drawTextWithShadow(rt, str, x, y, scale, clr)
+	return internal.ArcadeFont.DrawTextWithShadow(rt, str, x, y, scale, clr)
 }
 
 func drawTextWithShadowRight(rt *ebiten.Image, str string, x, y, scale int, clr color.Color, width int) error {
-	w := textWidth(str) * scale
+	w := internal.ArcadeFont.TextWidth(str) * scale
 	x += width - w
-	return drawTextWithShadow(rt, str, x, y, scale, clr)
+	return internal.ArcadeFont.DrawTextWithShadow(rt, str, x, y, scale, clr)
 }

example/blocks/blocks/gamescene.go

@@ -17,6 +17,7 @@ package blocks
 import (
 	"github.com/hajimehoshi/ebiten"
 	"github.com/hajimehoshi/ebiten/ebitenutil"
+	"github.com/hajimehoshi/ebiten/example/internal"
 	"image/color"
 	_ "image/jpeg"
 	"math/rand"
@@ -84,7 +85,7 @@ func init() {
 	}
 	// Windows: Next
 	x, y = nextWindowLabelPosition()
-	if err := drawTextWithShadow(imageWindows, "NEXT", x, y, 1, fontColor); err != nil {
+	if err := internal.ArcadeFont.DrawTextWithShadow(imageWindows, "NEXT", x, y, 1, fontColor); err != nil {
 		panic(err)
 	}
 	x, y = nextWindowPosition()
@@ -126,7 +127,7 @@ func drawWindow(r *ebiten.Image, x, y, width, height int) error {
 var fontColor = color.NRGBA{0x40, 0x40, 0xff, 0xff}
 
 func drawTextBox(r *ebiten.Image, label string, x, y, width int) error {
-	if err := drawTextWithShadow(r, label, x, y, 1, fontColor); err != nil {
+	if err := internal.ArcadeFont.DrawTextWithShadow(r, label, x, y, 1, fontColor); err != nil {
 		return err
 	}
 	y += blockWidth

example/blocks/blocks/titlescene.go

@@ -17,6 +17,7 @@ package blocks
 import (
 	"github.com/hajimehoshi/ebiten"
 	"github.com/hajimehoshi/ebiten/ebitenutil"
+	"github.com/hajimehoshi/ebiten/example/internal"
 	"image/color"
 )
 
@@ -83,9 +84,9 @@ func (s *TitleScene) Draw(r *ebiten.Image) error {
 	}
 
 	message := "PRESS SPACE TO START"
-	x := (ScreenWidth - textWidth(message)) / 2
+	x := (ScreenWidth - internal.ArcadeFont.TextWidth(message)) / 2
 	y := ScreenHeight - 48
-	return drawTextWithShadow(r, message, x, y, 1, color.NRGBA{0x80, 0, 0, 0xff})
+	return internal.ArcadeFont.DrawTextWithShadow(r, message, x, y, 1, color.NRGBA{0x80, 0, 0, 0xff})
 }
 
 func (s *TitleScene) drawTitleBackground(r *ebiten.Image, c int) error {
@@ -97,8 +98,8 @@ func (s *TitleScene) drawTitleBackground(r *ebiten.Image, c int) error {
 
 func drawLogo(r *ebiten.Image, str string) error {
 	scale := 4
-	textWidth := textWidth(str) * scale
+	textWidth := internal.ArcadeFont.TextWidth(str) * scale
 	x := (ScreenWidth - textWidth) / 2
 	y := 32
-	return drawTextWithShadow(r, str, x, y, scale, color.NRGBA{0x00, 0x00, 0x80, 0xff})
+	return internal.ArcadeFont.DrawTextWithShadow(r, str, x, y, scale, color.NRGBA{0x00, 0x00, 0x80, 0xff})
 }

example/images/license.md

@@ -1,6 +1,6 @@
 # License
 
-## blocks/font.png
+## arcadefont.png
 
 ```
 9031 Font ReadMe

example/internal/font.go

@@ -0,0 +1,111 @@
+// Copyright 2015 Hajime Hoshi
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal
+
+import (
+	"github.com/hajimehoshi/ebiten"
+	"github.com/hajimehoshi/ebiten/ebitenutil"
+	"image/color"
+	"math"
+	"strings"
+)
+
+var (
+	ArcadeFont *Font
+)
+
+type Font struct {
+	image          *ebiten.Image
+	offset         int
+	charNumPerLine int
+	charWidth      int
+	charHeight     int
+}
+
+func (f *Font) TextWidth(str string) int {
+	// TODO: Take care about '\n'
+	return f.charWidth * len(str)
+}
+
+func init() {
+	arcadeFontImage, _, err := ebitenutil.NewImageFromFile("images/arcadefont.png", ebiten.FilterNearest)
+	if err != nil {
+		panic(err)
+	}
+	ArcadeFont = &Font{arcadeFontImage, 32, 16, 8, 8}
+}
+
+type fontImageParts struct {
+	str  string
+	font *Font
+}
+
+func (f *fontImageParts) Len() int {
+	return len(f.str)
+}
+
+func (f *fontImageParts) Dst(i int) (x0, y0, x1, y1 int) {
+	x := i - strings.LastIndex(f.str[:i], "\n") - 1
+	y := strings.Count(f.str[:i], "\n")
+	x *= f.font.charWidth
+	y *= f.font.charHeight
+	if x < 0 {
+		return 0, 0, 0, 0
+	}
+	return x, y, x + f.font.charWidth, y + f.font.charHeight
+}
+
+func (f *fontImageParts) Src(i int) (x0, y0, x1, y1 int) {
+	code := int(f.str[i])
+	if code == '\n' {
+		return 0, 0, 0, 0
+	}
+	x := (code % f.font.charNumPerLine) * f.font.charWidth
+	y := ((code - f.font.offset) / f.font.charNumPerLine) * f.font.charHeight
+	return x, y, x + f.font.charWidth, y + f.font.charHeight
+}
+
+func (f *Font) DrawText(rt *ebiten.Image, str string, ox, oy, scale int, c color.Color) error {
+	options := &ebiten.DrawImageOptions{
+		ImageParts: &fontImageParts{str, f},
+	}
+	options.GeoM.Scale(float64(scale), float64(scale))
+	options.GeoM.Translate(float64(ox), float64(oy))
+
+	ur, ug, ub, ua := c.RGBA()
+	const max = math.MaxUint16
+	r := float64(ur) / max
+	g := float64(ug) / max
+	b := float64(ub) / max
+	a := float64(ua) / max
+	if 0 < a {
+		r /= a
+		g /= a
+		b /= a
+	}
+	options.ColorM.Scale(r, g, b, a)
+
+	return rt.DrawImage(f.image, options)
+}
+
+func (f *Font) DrawTextWithShadow(rt *ebiten.Image, str string, x, y, scale int, clr color.Color) error {
+	if err := f.DrawText(rt, str, x+1, y+1, scale, color.NRGBA{0, 0, 0, 0x80}); err != nil {
+		return err
+	}
+	if err := f.DrawText(rt, str, x, y, scale, clr); err != nil {
+		return err
+	}
+	return nil
+}