func New(w, h vg.Length) *Canvas {
buf := new(bytes.Buffer)
c := &Canvas{
svg: svgo.New(buf),
w: w,
h: h,
buf: buf,
ht: w.Points(),
stk: []context{context{}},
}
// This is like svg.Start, except it uses floats
// and specifies the units.
fmt.Fprintf(buf, `<?xml version="1.0"?>
<!-- Generated by SVGo and Plotinum VG -->
<svg width="%.*gin" height="%.*gin"
xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink">`+"\n",
pr, w.Inches(), pr, h.Inches())
// Swap the origin to the bottom left.
// This must be matched with a </g> when saving,
// before the closing </svg>.
c.svg.Gtransform(fmt.Sprintf("scale(1, -1) translate(0, -%.*g)", pr, h.Dots(c)))
vg.Initialize(c)
return c
}
// New creates a new PDF Canvas.
func New(w, h vg.Length) *Canvas {
c := &Canvas{
doc: pdf.New(),
w: w,
h: h,
}
c.page = c.doc.NewPage(unit(w), unit(h))
vg.Initialize(c)
return c
}
// NewImage returns a new image canvas
// that draws to the given image. The
// minimum point of the given image
// should probably be 0,0.
func NewImage(img draw.Image) *Canvas {
w := float64(img.Bounds().Max.X - img.Bounds().Min.X)
h := float64(img.Bounds().Max.Y - img.Bounds().Min.Y)
draw.Draw(img, img.Bounds(), image.White, image.ZP, draw.Src)
gc := draw2d.NewGraphicContext(img)
gc.SetDPI(dpi)
gc.Scale(1, -1)
gc.Translate(0, -h)
c := &Canvas{
gc: gc,
img: img,
w: vg.Inches(w / dpi),
h: vg.Inches(h / dpi),
color: []color.Color{color.Black},
}
vg.Initialize(c)
return c
}
// NewTitle returns a new Canvas with the given title string.
func NewTitle(w, h vg.Length, title string) *Canvas {
c := &Canvas{
stk: []ctx{ctx{}},
w: w,
h: h,
buf: new(bytes.Buffer),
}
c.buf.WriteString("%%!PS-Adobe-3.0 EPSF-3.0\n")
c.buf.WriteString("%%Creator code.google.com/p/plotinum/vg/veceps\n")
c.buf.WriteString("%%Title: " + title + "\n")
c.buf.WriteString(fmt.Sprintf("%%%%BoundingBox: 0 0 %.*g %.*g\n",
pr, w.Dots(c),
pr, h.Dots(c)))
c.buf.WriteString(fmt.Sprintf("%%%%CreationDate: %s\n", time.Now()))
c.buf.WriteString("%%Orientation: Portrait\n")
c.buf.WriteString("%%EndComments\n")
c.buf.WriteString("\n")
vg.Initialize(c)
return c
}
// NewImage returns a new image canvas
// that draws to the given image. The
// minimum point of the given image
// should probably be 0,0.
func NewImage(img draw.Image, name string) (*XImgCanvas, error) {
w := float64(img.Bounds().Max.X - img.Bounds().Min.X)
h := float64(img.Bounds().Max.Y - img.Bounds().Min.Y)
X, err := xgbutil.NewConn()
if err != nil {
return nil, err
}
keybind.Initialize(X)
ximg := xgraphics.New(X, image.Rect(0, 0, int(w), int(h)))
err = ximg.CreatePixmap()
if err != nil {
return nil, err
}
painter := NewXimgPainter(ximg)
gc := draw2d.NewGraphicContextWithPainter(ximg, painter)
gc.SetDPI(dpi)
gc.Scale(1, -1)
gc.Translate(0, -h)
wid := ximg.XShowExtra(name, true)
go func() {
xevent.Main(X)
}()
c := &XImgCanvas{
gc: gc,
w: vg.Inches(w / dpi),
h: vg.Inches(h / dpi),
color: []color.Color{color.Black},
x: X,
ximg: ximg,
wid: wid,
}
vg.Initialize(c)
return c, nil
}