Example #1
0
func main() {
	var color string
	openvg.Start(width, height)
	openvg.Background(200, 200, 200)
	for i := 0; i < niter; i++ {
		x := random(0, width)
		y := random(height/3, (height*2)/3)
		r := random(0, 10000)
		switch {
		case r >= 0 && r <= 2500:
			color = "white"
		case r > 2500 && r <= 5000:
			color = "maroon"
		case r > 5000 && r <= 7500:
			color = "gray"
		case r > 7500 && r <= 10000:
			color = "black"
		}
		openvg.FillColor(color, openvg.VGfloat(opacity))
		openvg.Circle(openvg.VGfloat(x), openvg.VGfloat(y), openvg.VGfloat(size))
	}
	openvg.End()
	bufio.NewReader(os.Stdin).ReadByte()
	openvg.Finish()
}
Example #2
0
// imgtest draws images at the corners and center
func imagetest(w, h int) {
	openvg.Start(w, h)
	imgw := 422
	imgh := 238
	fiw := float64(imgw)
	fih := float64(imgh)
	fw := float64(w)
	fh := float64(h)
	cx := (fw / 2) - (fiw / 2)
	cy := (fh / 2) - (fih / 2)
	ulx := 0.0
	uly := fh - fih
	urx := fw - fiw
	ury := uly
	llx := 0.0
	lly := 0.0
	lrx := urx
	lry := lly
	openvg.Start(w, h)
	openvg.Background(0, 0, 0)
	openvg.Image(cx, cy, imgw, imgh, "desert1.jpg")
	openvg.Image(ulx, uly, imgw, imgh, "desert2.jpg")
	openvg.Image(urx, ury, imgw, imgh, "desert3.jpg")
	openvg.Image(llx, lly, imgw, imgh, "desert4.jpg")
	openvg.Image(lrx, lry, imgw, imgh, "desert5.jpg")
	openvg.End()
}
Example #3
0
func main() {
	var cx, cy, cw, ch, midy int
	message := "Now is the time for all good men to come to the aid of the party"

	w, h := openvg.Init()
	var speed openvg.VGfloat = 15.0
	var x openvg.VGfloat = 0
	midy = (h / 2)
	fontsize := w / 50
	cx = 0
	ch = fontsize * 2
	cw = w
	cy = midy - (ch / 2)

	rx, ry, rw, rh := openvg.VGfloat(cx), openvg.VGfloat(cy), openvg.VGfloat(cw), openvg.VGfloat(ch)
	// scroll the text, only in the clipping rectangle
	for x = 0; x < rw+speed; x += speed {
		openvg.Start(w, h)
		openvg.Background(255, 255, 255)
		openvg.FillRGB(0, 0, 0, .2)
		openvg.Rect(rx, ry, rw, rh)
		openvg.ClipRect(cx, cy, cw, ch)
		openvg.Translate(x, ry+openvg.VGfloat(fontsize/2))
		openvg.FillRGB(0, 0, 0, 1)
		openvg.Text(0, 0, message, "sans", fontsize)
		openvg.ClipEnd()
		openvg.End()
	}
	bufio.NewReader(os.Stdin).ReadBytes('\n')
	openvg.Finish()
	os.Exit(0)
}
Example #4
0
func paintBG(w, h openvg.VGfloat) {
	if !showTrails {
		openvg.Background(0, 0, 0)
		return
	}
	openvg.FillRGB(0, 0, 0, 0.3)
	openvg.Rect(0, 0, w, h)
}
Example #5
0
// raspberry pi, scaled to the screen dimensions
func raspi(w, h int, s string) {
	midx := float64(w) / 2
	midy := float64(h) / 2
	rw := midx
	rh := (rw * 2) / 3
	fontsize := w / 25
	openvg.Start(w, h)
	openvg.Background(255, 255, 255)
	makepi(midx-(rw/2), midy-(rh/2), rw, rh)
	openvg.FillRGB(128, 0, 0, 1)
	openvg.TextMid(midx, midy-(rh/2)-float64(fontsize*2), s, "sans", fontsize)
	openvg.End()
}
Example #6
0
// raspberry pi, scaled to the screen dimensions
func main() {
	w, h := openvg.Init()
	midx := openvg.VGfloat(w) / 2
	midy := openvg.VGfloat(h) / 2
	rw := midx
	rh := (rw * 2) / 3
	fontsize := w / 25
	openvg.Start(w, h)
	openvg.Background(255, 255, 255)
	makepi(midx-(rw/2), midy-(rh/2), rw, rh)
	makepi(200, 100, 75, 50)
	openvg.FillRGB(128, 0, 0, 1)
	openvg.TextMid(midx, midy-(rh/2)-openvg.VGfloat(fontsize*2), "The Raspberry Pi", "sans", fontsize)
	WaitEnd()
}
Example #7
0
// sunearth shows the relative sizes of the sun and the earth
func sunearth(w, h int) {
	var sun, earth, x, y float64

	openvg.Start(w, h)
	openvg.Background(0, 0, 0)
	openvg.FillRGB(255, 255, 255, 1)
	for i := 0; i < w/4; i++ {
		x = randf(w)
		y = randf(h)
		openvg.Circle(x, y, 2)
	}
	earth = float64(w) * 0.010
	sun = earth * 109
	openvg.FillRGB(0, 0, 255, 1)
	openvg.Circle(float64(w/3), float64(h-(h/10)), earth)
	openvg.FillRGB(255, 255, 224, 1)
	openvg.Circle(float64(w), 0, sun)
	openvg.End()
}
Example #8
0
// rotext draws text, rotated around the center of the screen, progressively faded
func rotext(w, h, n int, s string) {
	fade := (100.0 / float64(n)) / 100.0
	deg := 360.0 / float64(n)
	x := float64(w) / 2.0
	y := float64(h) / 2.0
	alpha := 1.0
	size := w / 8

	openvg.Start(w, h)
	openvg.Background(0, 0, 0)
	openvg.Translate(x, y)
	for i := 0; i < n; i++ {
		openvg.FillRGB(255, 255, 255, alpha)
		openvg.Text(0, 0, s, "serif", size)
		alpha -= fade // fade
		size += n     // enlarge
		openvg.Rotate(deg)
	}
	openvg.End()
}
Example #9
0
// fontrange shows a range of fonts
func fontrange(w, h int) {
	var x, lx, length float64
	y := float64(h) / 2.0
	w2 := float64(w) / 2.0
	spacing := 50.0
	s2 := spacing / 2.0
	sizes := []int{6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 21, 24, 36, 48, 60, 72, 96}

	openvg.Start(w, h)
	openvg.Background(255, 255, 255)

	// compute the length so we can center
	length = 0.0
	for _, s := range sizes {
		length += float64(s) + spacing
	}
	length -= spacing
	lx = w2 - (length / 2) // center point

	// for each size, display a character and label
	x = lx
	for _, s := range sizes {
		openvg.FillRGB(128, 0, 0, 1)
		openvg.TextMid(x, y, "a", "serif", s)
		openvg.FillRGB(128, 128, 128, 1)
		openvg.TextMid(x, y-spacing, fmt.Sprintf("%d", s), "sans", 16)
		x += float64(s) + spacing
	}
	// draw a openvg.Line below the characters, a curve above
	x -= spacing
	openvg.StrokeRGB(150, 150, 150, 0.5)
	openvg.StrokeWidth(2)
	openvg.Line(lx, y-s2, x, y-s2)
	openvg.FillRGB(255, 255, 255, 1)
	openvg.Qbezier(lx, y+s2, x, y+s2, x, y+(spacing*3))
	openvg.End()
}
Example #10
0
func main() {
	flag.Usage = func() {
		fmt.Fprintf(os.Stdout,
			`usage: %s [ opts ] image-path

Set specified image as an overlay screen via OpenVG lib.
Default is to put this image to the center.

`, os.Args[0])
		flag.PrintDefaults()
	}

	var resize bool
	var bg_color string
	flag.BoolVar(&resize, "resize", false, `Resize image to fit the screen (using "convert" binary.`)
	flag.StringVar(&bg_color, "bg-color", "",
		`Background color to use with centered image, in RRGGBB (hex, e.g. "aabbcc") format.`)

	flag.Parse()
	if flag.NArg() != 1 {
		log.Print("ERROR: Exactly one image-path argument must be specified.")
		flag.Usage()
	}
	var r, g, b uint8
	var err error
	if len(bg_color) == 0 {
		r, g, b = 0, 0, 0
	} else if len(bg_color) == 6 {
		n, err := strconv.ParseUint(bg_color[:2], 16, 8)
		if err == nil {
			r = uint8(n)
			n, err = strconv.ParseUint(bg_color[2:4], 16, 8)
		}
		if err == nil {
			g = uint8(n)
			n, err = strconv.ParseUint(bg_color[4:6], 16, 8)
		}
		if err == nil {
			b = uint8(n)
		}
	}
	if err != nil {
		log.Fatalf("ERROR: Failed to parse bg-color value (%v): %v", bg_color, err)
	}
	image_path := flag.Args()[0]

	exit_code := 0
	defer func() {
		os.Exit(exit_code)
	}()

	openvg.SaveTerm()
	w, h := openvg.Init()
	openvg.RawTerm()
	defer openvg.Finish()
	defer openvg.RestoreTerm()

	image_conf, err := get_image_conf(image_path)
	if err == nil && resize && (image_conf.Width != w || image_conf.Height != h) {
		image_path, err = resize_image(w, h, image_path)
	}
	if err != nil {
		log.Printf("ERROR: Failed to process image (%v): %v", image_path, err)
		exit_code = 1
	} else {
		sig_chan := make(chan os.Signal, 1)
		signal.Notify(sig_chan, os.Interrupt, os.Kill,
			syscall.SIGHUP, syscall.SIGTERM, syscall.SIGALRM)

		openvg.Start(w, h)
		openvg.Background(r, g, b)
		if resize {
			openvg.Image(0, 0, w, h, image_path)
		} else {
			x, y := openvg.VGfloat(w)/2-openvg.VGfloat(image_conf.Width)/2,
				openvg.VGfloat(h)/2-openvg.VGfloat(image_conf.Height)/2
			openvg.Image(x, y, image_conf.Width, image_conf.Height, image_path)
		}
		openvg.End()

		_ = <-sig_chan
	}
}