// rshapes draws shapes with random colors, openvg.Strokes, and sizes.
func rshapes(width, height, n int) {
var sx, sy, cx, cy, px, py, ex, ey, pox, poy openvg.VGfloat
np := 10
polyx := make([]openvg.VGfloat, np)
polyy := make([]openvg.VGfloat, np)
openvg.Start(width, height)
for i := 0; i < n; i++ {
openvg.FillRGB(randcolor(), randcolor(), randcolor(), openvg.VGfloat(rand.Float32()))
openvg.Ellipse(randf(width), randf(height), randf(200), randf(100))
openvg.Circle(randf(width), randf(height), randf(100))
openvg.Rect(randf(width), randf(height), randf(200), randf(100))
openvg.Arc(randf(width), randf(height), randf(200), randf(200), randf(360), randf(360))
sx = randf(width)
sy = randf(height)
openvg.StrokeRGB(randcolor(), randcolor(), randcolor(), 1)
openvg.StrokeWidth(randf(5))
openvg.Line(sx, sy, sx+randf(200), sy+randf(100))
openvg.StrokeWidth(0)
sx = randf(width)
sy = randf(height)
ex = sx + randf(200)
ey = sy
cx = sx + ((ex - sx) / 2.0)
cy = sy + randf(100)
openvg.Qbezier(sx, sy, cx, cy, ex, ey)
sx = randf(width)
sy = randf(height)
ex = sx + randf(200)
ey = sy
cx = sx + ((ex - sx) / 2.0)
cy = sy + randf(100)
px = cx
py = sy - randf(100)
openvg.Cbezier(sx, sy, cx, cy, px, py, ex, ey)
pox = randf(width)
poy = randf(height)
for j := 0; j < np; j++ {
polyx[j] = pox + randf(200)
polyy[j] = poy + randf(100)
}
openvg.Polygon(polyx, polyy) // , np)
pox = randf(width)
poy = randf(height)
for j := 0; j < np; j++ {
polyx[j] = pox + randf(200)
polyy[j] = poy + randf(100)
}
openvg.Polyline(polyx, polyy) // , np)
}
openvg.FillRGB(128, 0, 0, 1)
openvg.Text(20, 20, "OpenVG on the Raspberry Pi", "sans", 32)
openvg.End()
}
// fontrange shows a range of fonts
func fontrange(w, h int) {
var x, lx, length openvg.VGfloat
y := openvg.VGfloat(h) / 2.0
w2 := openvg.VGfloat(w) / 2.0
spacing := openvg.VGfloat(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 += openvg.VGfloat(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 += openvg.VGfloat(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()
}
// refcard shows a reference card of shapes
func refcard(width, height int) {
shapenames := []string{
"Circle",
"Ellipse",
"Rectangle",
"Rounded Rectangle",
"Line",
"Polyline",
"Polygon",
"Arc",
"Quadratic Bezier",
"Cubic Bezier",
"Image",
}
top := openvg.VGfloat(height) * .95
sx := openvg.VGfloat(width) * 0.10
sy := top
sw := openvg.VGfloat(width) * .05
sh := openvg.VGfloat(height) * .045
dotsize := openvg.VGfloat(7.0)
spacing := openvg.VGfloat(2.0)
fontsize := int(openvg.VGfloat(height) * .033)
shapecolor := Color{202, 225, 255, 1.0}
openvg.Start(width, height)
openvg.FillRGB(128, 0, 0, 1)
openvg.TextEnd(openvg.VGfloat(width-20), openvg.VGfloat(height/2),
"OpenVG on the Raspberry Pi", "sans", fontsize+(fontsize/2))
openvg.FillRGB(0, 0, 0, 1)
for _, s := range shapenames {
openvg.Text(sx+sw+sw/2, sy, s, "sans", fontsize)
sy -= sh * spacing
}
sy = top
cx := sx + (sw / 2)
ex := sx + sw
openvg.FillRGB(shapecolor.red, shapecolor.green, shapecolor.blue, shapecolor.alpha)
openvg.Circle(cx, sy, sw)
coordpoint(cx, sy, dotsize, shapecolor)
sy -= sh * spacing
openvg.Ellipse(cx, sy, sw, sh)
coordpoint(cx, sy, dotsize, shapecolor)
sy -= sh * spacing
openvg.Rect(sx, sy, sw, sh)
coordpoint(sx, sy, dotsize, shapecolor)
sy -= sh * spacing
openvg.Roundrect(sx, sy, sw, sh, 20, 20)
coordpoint(sx, sy, dotsize, shapecolor)
sy -= sh * spacing
openvg.StrokeWidth(1)
openvg.StrokeRGB(204, 204, 204, 1)
openvg.Line(sx, sy, ex, sy)
coordpoint(sx, sy, dotsize, shapecolor)
coordpoint(ex, sy, dotsize, shapecolor)
sy -= sh
px := []openvg.VGfloat{sx, sx + (sw / 4), sx + (sw / 2), sx + ((sw * 3) / 4), sx + sw}
py := []openvg.VGfloat{sy, sy - sh, sy, sy - sh, sy}
openvg.Polyline(px, py) // , 5)
coordpoint(px[0], py[0], dotsize, shapecolor)
coordpoint(px[1], py[1], dotsize, shapecolor)
coordpoint(px[2], py[2], dotsize, shapecolor)
coordpoint(px[3], py[3], dotsize, shapecolor)
coordpoint(px[4], py[4], dotsize, shapecolor)
sy -= sh * spacing
py[0] = sy
py[1] = sy - sh
py[2] = sy - (sh / 2)
py[3] = py[1] - (sh / 4)
py[4] = sy
openvg.Polygon(px, py) // , 5)
sy -= (sh * spacing) + sh
openvg.Arc(sx+(sw/2), sy, sw, sh, 0, 180)
coordpoint(sx+(sw/2), sy, dotsize, shapecolor)
sy -= sh * spacing
var cy, ey openvg.VGfloat
cy = sy + (sh / 2)
ey = sy
openvg.Qbezier(sx, sy, cx, cy, ex, ey)
coordpoint(sx, sy, dotsize, shapecolor)
coordpoint(cx, cy, dotsize, shapecolor)
coordpoint(ex, ey, dotsize, shapecolor)
sy -= sh * spacing
ey = sy
cy = sy + sh
openvg.Cbezier(sx, sy, cx, cy, cx, sy, ex, ey)
coordpoint(sx, sy, dotsize, shapecolor)
coordpoint(cx, cy, dotsize, shapecolor)
coordpoint(cx, sy, dotsize, shapecolor)
coordpoint(ex, ey, dotsize, shapecolor)
sy -= (sh * spacing * 1.5)
openvg.Image(sx, sy, 110, 110, "starx.jpg")
openvg.End()
}
// showlide displays slides
func showslide(d deck.Deck, imap map[string]image.Image, n int) {
var video videoType
if n < 0 || n > len(d.Slide)-1 {
return
}
slide := d.Slide[n]
if slide.Bg == "" {
slide.Bg = "white"
}
if slide.Fg == "" {
slide.Fg = "black"
}
openvg.Start(d.Canvas.Width, d.Canvas.Height)
cw := openvg.VGfloat(d.Canvas.Width)
ch := openvg.VGfloat(d.Canvas.Height)
if slide.Gradcolor1 != "" && slide.Gradcolor2 != "" {
oc := []openvg.Offcolor{
{0, openvg.Colorlookup(slide.Gradcolor1), 1},
{1, openvg.Colorlookup(slide.Gradcolor2), 1},
}
openvg.FillLinearGradient(0, ch, 0, 0, oc)
} else {
openvg.FillColor(slide.Bg)
}
openvg.Rect(0, 0, cw, ch)
var x, y, fs openvg.VGfloat
// every image in the slide
for _, im := range slide.Image {
x = pct(im.Xp, cw)
y = pct(im.Yp, ch)
imw := openvg.VGfloat(im.Width)
imh := openvg.VGfloat(im.Height)
if im.Scale > 0 {
imw *= openvg.VGfloat(im.Scale / 100)
imh *= openvg.VGfloat(im.Scale / 100)
}
midx := openvg.VGfloat(imw / 2)
midy := openvg.VGfloat(imh / 2)
if im.Type == "video" {
// Only one video per slide supported
video.name = im.Name
video.x = x - midx
video.y = y - midy
video.w = imw
video.h = imh
video.altimg = im.Link
} else {
img, ok := imap[im.Name]
if ok {
openvg.Img(x-midx, y-midy, img)
}
if len(im.Caption) > 0 {
capfs := pctwidth(im.Sp, cw, cw/100)
if im.Font == "" {
im.Font = "sans"
}
if im.Color == "" {
openvg.FillColor(slide.Fg)
} else {
openvg.FillColor(im.Color)
}
if im.Align == "" {
im.Align = "center"
}
switch im.Align {
case "left", "start":
x -= midx
case "right", "end":
x += midx
}
showtext(x, y-((midy)+(capfs*2.0)), im.Caption, im.Align, im.Font, capfs)
}
}
}
// every graphic on the slide
const defaultColor = "rgb(127,127,127)"
const defaultSw = 1.5
var strokeopacity float64
// line
for _, line := range slide.Line {
if line.Color == "" {
line.Color = slide.Fg // defaultColor
}
if line.Opacity == 0 {
strokeopacity = 1
} else {
strokeopacity = line.Opacity / 100.0
}
x1, y1, sw := dimen(d, line.Xp1, line.Yp1, line.Sp)
x2, y2, _ := dimen(d, line.Xp2, line.Yp2, 0)
openvg.StrokeColor(line.Color, openvg.VGfloat(strokeopacity))
if sw == 0 {
sw = defaultSw
}
openvg.StrokeWidth(openvg.VGfloat(sw))
openvg.StrokeColor(line.Color)
openvg.Line(x1, y1, x2, y2)
openvg.StrokeWidth(0)
}
// ellipse
for _, ellipse := range slide.Ellipse {
x, y, _ = dimen(d, ellipse.Xp, ellipse.Yp, 0)
var w, h openvg.VGfloat
w = pct(ellipse.Wp, cw)
if ellipse.Hr == 0 { // if relative height not specified, base height on overall height
h = pct(ellipse.Hp, ch)
} else {
h = pct(ellipse.Hr, w)
}
if ellipse.Color == "" {
ellipse.Color = defaultColor
}
if ellipse.Opacity == 0 {
ellipse.Opacity = 1
} else {
ellipse.Opacity /= 100
}
openvg.FillColor(ellipse.Color, openvg.VGfloat(ellipse.Opacity))
openvg.Ellipse(x, y, w, h)
}
// rect
for _, rect := range slide.Rect {
x, y, _ = dimen(d, rect.Xp, rect.Yp, 0)
var w, h openvg.VGfloat
w = pct(rect.Wp, cw)
if rect.Hr == 0 { // if relative height not specified, base height on overall height
h = pct(rect.Hp, ch)
} else {
h = pct(rect.Hr, w)
}
if rect.Color == "" {
rect.Color = defaultColor
}
if rect.Opacity == 0 {
rect.Opacity = 1
} else {
rect.Opacity /= 100
}
openvg.FillColor(rect.Color, openvg.VGfloat(rect.Opacity))
openvg.Rect(x-(w/2), y-(h/2), w, h)
}
// curve
for _, curve := range slide.Curve {
if curve.Color == "" {
curve.Color = defaultColor
}
if curve.Opacity == 0 {
strokeopacity = 1
} else {
strokeopacity = curve.Opacity / 100.0
}
x1, y1, sw := dimen(d, curve.Xp1, curve.Yp1, curve.Sp)
x2, y2, _ := dimen(d, curve.Xp2, curve.Yp2, 0)
x3, y3, _ := dimen(d, curve.Xp3, curve.Yp3, 0)
openvg.StrokeColor(curve.Color, openvg.VGfloat(strokeopacity))
openvg.FillColor(slide.Bg, openvg.VGfloat(curve.Opacity))
if sw == 0 {
sw = defaultSw
}
openvg.StrokeWidth(sw)
openvg.Qbezier(x1, y1, x2, y2, x3, y3)
openvg.StrokeWidth(0)
}
// arc
for _, arc := range slide.Arc {
if arc.Color == "" {
arc.Color = defaultColor
}
if arc.Opacity == 0 {
strokeopacity = 1
} else {
strokeopacity = arc.Opacity / 100.0
}
ax, ay, sw := dimen(d, arc.Xp, arc.Yp, arc.Sp)
w := pct(arc.Wp, cw)
h := pct(arc.Hp, cw)
openvg.StrokeColor(arc.Color, openvg.VGfloat(strokeopacity))
openvg.FillColor(slide.Bg, openvg.VGfloat(arc.Opacity))
if sw == 0 {
sw = defaultSw
}
openvg.StrokeWidth(sw)
openvg.Arc(ax, ay, w, h, openvg.VGfloat(arc.A1), openvg.VGfloat(arc.A2))
openvg.StrokeWidth(0)
}
// polygon
for _, poly := range slide.Polygon {
if poly.Color == "" {
poly.Color = defaultColor
}
if poly.Opacity == 0 {
poly.Opacity = 1
} else {
poly.Opacity /= 100
}
xs := strings.Split(poly.XC, " ")
ys := strings.Split(poly.YC, " ")
if len(xs) != len(ys) {
continue
}
if len(xs) < 3 || len(ys) < 3 {
continue
}
px := make([]openvg.VGfloat, len(xs))
py := make([]openvg.VGfloat, len(ys))
for i := 0; i < len(xs); i++ {
x, err := strconv.ParseFloat(xs[i], 32)
if err != nil {
px[i] = 0
} else {
px[i] = pct(x, cw)
}
y, err := strconv.ParseFloat(ys[i], 32)
if err != nil {
py[i] = 0
} else {
py[i] = pct(y, ch)
}
}
openvg.FillColor(poly.Color, openvg.VGfloat(poly.Opacity))
openvg.Polygon(px, py)
}
openvg.FillColor(slide.Fg)
// every list in the slide
var offset, textopacity openvg.VGfloat
const blinespacing = 2.4
for _, l := range slide.List {
if l.Font == "" {
l.Font = "sans"
}
x, y, fs = dimen(d, l.Xp, l.Yp, l.Sp)
if l.Type == "bullet" {
offset = 1.2 * fs
} else {
offset = 0
}
if l.Lp == 0 {
l.Lp = blinespacing
}
if l.Opacity == 0 {
textopacity = 1
} else {
textopacity = openvg.VGfloat(l.Opacity / 100)
}
// every list item
var li, lifont string
for ln, tl := range l.Li {
if len(l.Color) > 0 {
openvg.FillColor(l.Color, textopacity)
} else {
openvg.FillColor(slide.Fg)
}
if l.Type == "bullet" {
boffset := fs / 2
openvg.Ellipse(x, y+boffset, boffset, boffset)
//openvg.Rect(x, y+boffset/2, boffset, boffset)
}
if l.Type == "number" {
li = fmt.Sprintf("%d. ", ln+1) + tl.ListText
} else {
li = tl.ListText
}
if len(tl.Color) > 0 {
openvg.FillColor(tl.Color, textopacity)
}
if len(tl.Font) > 0 {
lifont = tl.Font
} else {
lifont = l.Font
}
showtext(x+offset, y, li, l.Align, lifont, fs)
y -= fs * openvg.VGfloat(l.Lp)
}
}
openvg.FillColor(slide.Fg)
// every text in the slide
const linespacing = 1.8
var tdata string
for _, t := range slide.Text {
if t.File != "" {
tdata = includefile(t.File)
} else {
tdata = t.Tdata
}
if t.Font == "" {
t.Font = "sans"
}
if t.Opacity == 0 {
textopacity = 1
} else {
textopacity = openvg.VGfloat(t.Opacity / 100)
}
if t.Lp == 0 {
t.Lp = linespacing
}
x, y, fs = dimen(d, t.Xp, t.Yp, t.Sp)
td := strings.Split(tdata, "\n")
if t.Type == "code" {
ls := fs * openvg.VGfloat(t.Lp)
t.Font = "mono"
tdepth := (ls * openvg.VGfloat(len(td))) + fs
openvg.FillColor("rgb(240,240,240)")
openvg.Rect(x-20, y-tdepth+(ls), pctwidth(t.Wp, cw, cw-x-20), tdepth)
}
if t.Color == "" {
openvg.FillColor(slide.Fg, textopacity)
} else {
openvg.FillColor(t.Color, textopacity)
}
if t.Type == "block" {
textwrap(x, y, pctwidth(t.Wp, cw, cw/2), tdata, t.Font, fs, fs*openvg.VGfloat(t.Lp), 0.3)
} else {
// every text line
ls := fs * openvg.VGfloat(t.Lp)
for _, txt := range td {
showtext(x, y, txt, t.Align, t.Font, fs)
y -= ls
}
}
}
openvg.FillColor(slide.Fg)
openvg.End()
if video.altimg != "" {
img, ok := imap[video.altimg]
if ok {
openvg.Img(video.x, video.y, img)
}
}
if video.name != "" {
openvg.Video(video.x, video.y, video.w, video.h, video.name)
}
}