Simple PDF drawing library#

The package pdfdraw is a simple, low level, drawing library. It is mainly created because I cannot remember the PDF operators.

Use

func New() *Object

or

func NewStandalone() *Object

to get a PDF draw object:

type Object struct {
}

There are a lot of methods defined on the pdfdraw object, such as

func (pd *Object) Fill() *Object

which return the object itself. So you can call these methods by chaining:

myobj := pdfdraw.New()
myobj.ColorNonstroking(col).Moveto(x0, y0).Lineto(x1, y1).Lineto(x2, y1).Lineto(x3, y0).Close().Fill()

or by calling these methods from the object:

myobj := pdfdraw.New()
myobj.ColorNonstroking(col)
myobj.Moveto(x0, y0)
myobj.Lineto(x1, y1)
myobj.Lineto(x2, y1)
myobj.Lineto(x3, y0)
myobj.Close()
myobj.Fill()

After you have chained the methods together, you can call the .String() to get the textual representation of the drawing commands.

Standalone or not to stand alone?#

The NewStandalone() function creates a q...Q encapsulated PDF string, which is normally used to stop leaking settings for the next drawing commands.

Methods#

Method	Description	PDF operator
`Color(color.Color)`	Set the color for stroking and non-stroking operations	(depending on the color space)
`ColorStroking(color.Color)`	Set the color for stroking operations	(depending on the color space)
`ColorNonStroking(color.Color)`	Set the color for stroking operations	(depending on the color space)
`Close()`	Close the sub path	`h`
`Clip()`	Clip the sub path using the even-odd rule	`W*`
`Curveto(c1x,c1y,c2x,c2y,x1,y1 bag.ScaledPoint)`	Append a bezier curve from the current point to point 1 controlled by control points 1 and 2	`c`
`Endpath()`	End the current path	`n`
`Moveto(x, y bag.ScaledPoint)`	Move the cursor relative to the current point	`m`
`Lineto(x, y bag.ScaledPoint)`	Draw a straight line from the current point to the point given at x and y	`l`
`Circle(x, y, radiusX, radiusY bag.ScaledPoint)`	Draw a circle	mainly `c`
`Rect(x, y, wd, ht bag.ScaledPoint)`	Draw a rectangle	`re`
`Save()`	Save the graphics state	`q`
`Restore()`	Restore the graphics state	`Q`
`Fill()`	Fill the current object	`f`
`Stroke()`	Paint the current object without filling it	`S`
`StrokeFill()`	Paint the current object and fill it	`B`
`LineWidth(wd bag.ScaledPoint)`	Set the line width	`w`
`Literal(s string)`	Insert the string without interpretation	-
`SetDash(dasharray []uint, dashphase uint)`	SetDash sets the dash pattern	`d`
`String()`