gr

testdata/draw.d/go.mod

@@ -0,0 +1,7 @@
+module gogs.inhome.blapointe.com/anki.d/testdata/draw.d
+
+go 1.19
+
+require github.com/nsf/termbox-go v1.1.1
+
+require github.com/mattn/go-runewidth v0.0.9 // indirect

testdata/draw.d/go.sum

@@ -0,0 +1,4 @@
+github.com/mattn/go-runewidth v0.0.9 h1:Lm995f3rfxdpd6TSmuVCHVb/QhupuXlYr8sCI/QdE+0=
+github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
+github.com/nsf/termbox-go v1.1.1 h1:nksUPLCb73Q++DwbYUBEglYBRPZyoXJdrj5L+TkjyZY=
+github.com/nsf/termbox-go v1.1.1/go.mod h1:T0cTdVuOwf7pHQNtfhnEbzHbcNyCEcVU4YPpouCbVxo=

testdata/draw.d/main.go

@@ -0,0 +1,146 @@
+package main
+
+import (
+	"image"
+	"image/color"
+	_ "image/gif"
+	_ "image/jpeg"
+	_ "image/png"
+	"log"
+	"math"
+	"os"
+
+	termbox "github.com/nsf/termbox-go"
+)
+
+var palette color.Palette = []color.Color{
+	attrColor(termbox.ColorBlack),
+	attrColor(termbox.ColorRed),
+	attrColor(termbox.ColorGreen),
+	attrColor(termbox.ColorYellow),
+	attrColor(termbox.ColorBlue),
+	attrColor(termbox.ColorMagenta),
+	attrColor(termbox.ColorCyan),
+	attrColor(termbox.ColorWhite),
+}
+
+func upgrade(palette color.Palette) color.Palette {
+	for i := 16; i <= 255; i++ {
+		palette = append(palette, attrColor(i))
+	}
+	return palette
+}
+
+type attrColor termbox.Attribute
+
+var base = [...]uint8{0x00, 0x5f, 0x87, 0xaf, 0xd7, 0xff}
+
+func (c attrColor) RGBA() (r, g, b, a uint32) {
+	switch termbox.Attribute(c) {
+	case termbox.ColorBlack:
+		return 0, 0, 0, math.MaxUint16
+	case termbox.ColorRed:
+		return math.MaxUint16, 0, 0, math.MaxUint16
+	case termbox.ColorGreen:
+		return 0, math.MaxUint16, 0, math.MaxUint16
+	case termbox.ColorYellow:
+		return math.MaxUint16, math.MaxUint16, 0, math.MaxUint16
+	case termbox.ColorBlue:
+		return 0, 0, math.MaxUint16, math.MaxUint16
+	case termbox.ColorMagenta:
+		return math.MaxUint16, 0, math.MaxUint16, math.MaxUint16
+	case termbox.ColorCyan:
+		return 0, math.MaxUint16, math.MaxUint16, math.MaxUint16
+	case termbox.ColorWhite:
+		return math.MaxUint16, math.MaxUint16, math.MaxUint16, math.MaxUint16
+	}
+
+	switch {
+	case c >= 16 && c <= 231:
+		c -= 16
+		rgba := color.RGBA{R: base[(c/36)%6], G: base[(c/6)%6], B: base[c%6], A: 0xff}
+		return rgba.RGBA()
+	case c >= 232 && c <= 255:
+		x := uint8(0x08 + 0xa*(c-232))
+		rgba := color.RGBA{R: x, G: x, B: x, A: 0xff}
+		return rgba.RGBA()
+	}
+
+	panic("not found")
+}
+
+func fit(w, h, iw, ih int) (sw, sh int) {
+	if w >= iw && h >= ih {
+		// image is smaller than screen
+		return iw, ih
+	} else if w >= iw {
+		// image is taller than the screen
+		return iw * h / ih, h
+	} else if h >= ih {
+		// image is skinnier than the screen
+		return w, ih * w / iw
+	} else {
+		sw, sh = iw*h/ih, h
+		if sw <= w {
+			return sw, sh
+		}
+		return w, ih * w / iw
+	}
+}
+
+func draw(img image.Image) {
+	w, h := termbox.Size()
+	iw, ih := img.Bounds().Max.X, img.Bounds().Max.Y
+	sw, sh := fit(w, h, iw*2, ih)
+	termbox.Clear(termbox.ColorDefault, termbox.ColorDefault)
+	for y := 0; y < h; y++ {
+		for x := 0; x < w; x++ {
+			if x >= sw || y >= sh {
+				termbox.SetCell(x, y, ' ', termbox.ColorDefault, termbox.ColorDefault)
+				continue
+			}
+			xi := x * img.Bounds().Max.X / sw
+			yi := y * img.Bounds().Max.Y / sh
+			a := palette.Convert(img.At(xi, yi))
+			if at, ok := a.(attrColor); ok {
+				termbox.SetCell(x, y, ' ', termbox.ColorDefault,
+					termbox.Attribute(at))
+			}
+		}
+	}
+	termbox.Flush()
+}
+
+func main() {
+	fname := os.Args[1]
+
+	f, err := os.Open(fname)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer f.Close()
+
+	img, _, err := image.Decode(f)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = termbox.Init()
+	if err != nil {
+		panic(err)
+	}
+	defer termbox.Close()
+
+	if termbox.SetOutputMode(termbox.Output256) == termbox.Output256 {
+		palette = upgrade(palette)
+	}
+
+	lw, lh := termbox.Size()
+	draw(img)
+	termbox.PollEvent()
+	termbox.Flush()
+	if w, h := termbox.Size(); lw != w || lh != h {
+		lw, lh = w, h
+		draw(img)
+	}
+}

testdata/tiv.sh

@@ -13,6 +13,8 @@
 #   Unreadable:  1×2 (high resolution, slowest rendering, without double horizontal resolution)
 char_w=5
 char_h=8
+char_w=1
+char_h=2
 
 # If file doesn't exist, then die with 'No such file or directory' exit code
 if [ ! -f "$1" ]