NAME

PDF::API2::Content - Methods for adding graphics and text to a PDF

SYNOPSIS

    # Start with a PDF page (new or opened)
    my $pdf = PDF::API2->new();
    my $page = $pdf->page();
    
    # Add a new content object
    my $content = $page->gfx();
    my $content = $page->text();
    
    # Then call the methods below add graphics and text to the page.

METHODS

Coordinate Transformations

The methods in this section change the coordinate system for the current content object relative to the rest of the document.

If you call more than one of these methods, the PDF specification recommends calling them in the following order: translate, rotate, scale, skew. Each change builds on the last, and you can get unexpected results when calling them in a different order.

$content->translate($x, $y)

Moves the origin along the x and y axes.

$content->rotate($degrees)

Rotates the coordinate system counter-clockwise.

Use a negative argument to rotate clockwise.

$content->scale($sx, $sy)

Scales (stretches) the coordinate systems along the x and y axes.

$content->skew($sa, $sb)

Skews the coordinate system by $sa degrees (counter-clockwise) from the x axis and $sb degrees (clockwise) from the y axis.

$content->transform(%options)

    $content->transform(
        -translate => [$x, $y],
        -rotate    => $degrees,
        -scale     => [$sx, $sy],
        -skew      => [$sa, $sb],
    )

Performs multiple coordinate transformations at once, in the order recommended by the PDF specification (translate, rotate, scale, then skew).

This is equivalent to making each transformation separately.

$content->transform_rel(%options)

Makes transformations similarly to transform, except that it adds to the previously set values.

$content->matrix($a, $b, $c, $d, $e, $f)

(Advanced) Sets the current transformation matrix manually. Unless you have a particular need to enter transformations manually, you should use the transform method instead.

Graphics State Parameters

$content->save

Saves the current graphics state and text state on a stack.

$content->restore

Restores the most recently saved graphics state and text state, removing it from the stack.

$content->linewidth($width)

Sets the width of the stroke.

$content->linecap($style)

Sets the style to be used at the end of a stroke.

0 = Butt Cap

The stroke ends at the end of the path, with no projection.

1 = Round Cap

An arc is drawn around the end of the path with a diameter equal to the line width, and is filled in.

2 = Projecting Square Cap

The stroke continues past the end of the path for half the line width.

$content->linejoin($style)

Sets the style of join to be used at corners of a path.

0 = Miter Join

The outer edges of the stroke extend until they meet, up to the limit specified below. If the limit would be surpassed, a bevel join is used instead.

1 = Round Join

A circle with a diameter equal to the linewidth is drawn around the corner point, producing a rounded corner.

2 = Bevel Join

A triangle is drawn to fill in the notch between the two strokes.

$content->meterlimit($ratio)

Note: This method is named incorrectly, and will be renamed in a future release.

Sets the miter (not meter) limit when the line join style is a miter join.

The ratio is the maximum length of the miter divided by the line width. Any miter above this ratio will be converted to a bevel join.

$content->linedash()

$content->linedash($length)

$content->linedash($on, $off)

Sets the line dash pattern.

If passed without any arguments, a solid line will be drawn.

If passed with one argument, the strokes and spaces will have equal lengths.

If passed with two arguments, the strokes will have length $on, and the spaces will have length $off.

$content->flatness($tolerance)

(Advanced) Sets the maximum variation in output pixels when drawing curves.

$content->egstate($object)

(Advanced) Adds an Extended Graphic State object containing additional state parameters.

Path Construction (Drawing)

$content->move($x, $y)

Starts a new path at the specified coordinates.

$content->line($x, $y)

Extends the path in a line from the current coordinates to the specified coordinates, and updates the current position to be the new coordinates.

Note: The line will not appear until you call stroke.

$content->hline($x)

$content->vline($y)

Shortcut for drawing horizontal and vertical lines from the current position.

$content->poly($x1, $y1, ..., $xn, $yn)

Shortcut for creating a polyline path. Moves to [$x1, $y1], and then extends the path in lines along the specified coordinates.

$content->curve($cx1, $cy1, $cx2, $cy2, $x, $y)

Extends the path in a curve from the current point to ($x, $y), using the two specified points to create a cubic Bezier curve, and updates the current position to be the new point.

Note: The curve will not appear until you call stroke.

$content->spline($cx1, $cy1, $x, $y)

Extends the path in a curve from the current point to ($x, $y), using the two specified points to create a spline, and updates the current position to be the new point.

Note: The curve will not appear until you call stroke.

$content->arc($x, $y, $a, $b, $alpha, $beta, $move)

Extends the path along an arc of an ellipse centered at [x, y]. The major and minor axes of the ellipse are $a and $b, respectively, and the arc moves from $alpha degrees to $beta degrees. The current position is then set to the endpoint of the arc.

Set $move to a true value if this arc is the beginning of a new path instead of the continuation of an existing path.

$content->bogen($x1, $y1, $x2, $y2, $radius, $move, $outer, $reverse)

Extends the path along an arc of a circle of the specified radius between [x1, y1] to [x2, y2]. The current position is then set to the endpoint of the arc.

Set $move to a true value if this arc is the beginning of a new path instead of the continuation of an existing path.

Set $outer to a true value to draw the larger arc between the two points instead of the smaller one.

Set $reverse to a true value to draw the mirror image of the specified arc.

$radius * 2 cannot be smaller than the distance from [x1, y1] to [x2, y2].

Note: The curve will not appear until you call stroke.

$content->close

Closes and ends the current path by extending a line from the current position to the starting position.

$content->endpath

Ends the current path without explicitly enclosing it.

$content->ellipse($x, $y, $a, $b)

Creates an elliptical path centered on [$x, $y], with major and minor axes specified by $a and $b, respectively.

Note: The ellipse will not appear until you call stroke or fill.

$content->circle($x, $y, $radius)

Creates a circular path centered on [$x, $y] with the specified radius.

Note: The circle will not appear until you call stroke or fill.

$content->pie($x, $y, $a, $b, $alpha, $beta)

Creates a pie-shaped path from an ellipse centered on [$x, $y]. The major and minor axes of the ellipse are $a and $b, respectively, and the arc moves from $alpha degrees to $beta degrees.

Note: The pie will not appear until you call stroke or fill.

$content->rect($x1, $y1, $w1, $h1, ..., $xn, $yn, $wn, $hn)

Creates paths for one or more rectangles, with their lower left points at [$x, $y] and with the specified widths and heights.

Note: The rectangle will not appear until you call stroke or fill.

$content->rectxy($x1, $y1, $x2, $y2)

Creates a rectangular path, with [$x1, $y1] and and [$x2, $y2] specifying opposite corners.

Note: The rectangle will not appear until you call stroke or fill.

Path Painting (Drawing)

$content->stroke

Strokes the current path.

$content->fill($use_even_odd_fill)

Fills the current path.

If the path intersects with itself, the nonzero winding rule will be used to determine which part of the path is filled in. If you would prefer to use the even-odd rule, pass a true argument.

See the PDF Specification, section 8.5.3.3, for more details on filling.

$content->fillstroke($use_even_odd_fill)

Fills and then strokes the current path.

$content->clip($use_even_odd_fill)

Modifies the current clipping path by intersecting it with the current path.

Colors

$content->fillcolor($color)

$content->strokecolor($color)

Sets the fill or stroke color.

    # Use a named color
    $content->fillcolor('blue');

    # Use an RGB color (start with '#')
    $content->fillcolor('#FF0000');

    # Use a CMYK color (start with '%')
    $content->fillcolor('%FF000000');

RGB and CMYK colors can have one-byte, two-byte, three-byte, or four-byte values for each color. For instance, cyan can be given as %F000 or %FFFF000000000000.

External Objects

$content->image($image_object, $x, $y, $width, $height)

$content->image($image_object, $x, $y, $scale)

$content->image($image_object, $x, $y)

    # Example
    my $image_object = $pdf->image_jpeg($my_image_file);
    $content->image($image_object, 100, 200);

Places an image on the page in the specified location.

If coordinate transformations have been made (see Coordinate Transformations above), the position and scale will be relative to the updated coordinates. Otherwise, [0,0] will represent the bottom left corner of the page, and $width and $height will be measured at 72dpi.

For example, if you have a 600x600 image that you would like to be shown at 600dpi (i.e. one inch square), set the width and height to 72.

$content->formimage($form_object, $x, $y, $scale)

$content->formimage($form_object, $x, $y)

Places an XObject on the page in the specified location.

Text State Parameters

All of the following parameters that take a size are applied before any scaling takes place, so you don't need to adjust values to counteract scaling.

$spacing = $content->charspace($spacing)

Sets the spacing between characters. This is initially zero.

$spacing = $content->wordspace($spacing)

Sets the spacing between words. This is initially zero (or, in other words, just the width of the space).

$scale = $content->hspace($scale)

Note: This method is named incorrectly, and will be renamed in a future release.

Sets the percentage of horizontal text scaling (not spacing). This is initially 100 (i.e. no scaling), and must be passed as an integer.

$leading = $content->lead($leading)

Sets the text leading, which is the distance between baselines. This is initially zero (i.e. the lines will be printed on top of each other).

$mode = $content->render($mode)

Sets the text rendering mode.

0 = Fill text

1 = Stroke text (outline)

2 = Fill, then stroke text

3 = Neither fill nor stroke text (invisible)

4 = Fill text and add to path for clipping

5 = Stroke text and add to path for clipping

6 = Fill, then stroke text and add to path for clipping

7 = Add text to path for clipping

$distance = $content->rise($distance)

Adjusts the baseline up or down from its current location. This is initially zero.

Use this for creating superscripts or subscripts (usually with an adjustment to the font size as well).

%state = $content->textstate(charspace => $value, wordspace => $value, ...)

Shortcut for setting multiple text state parameters at once.

This can also be used without arguments to retrieve the current text state settings.

Note: This does not currently work with the save and restore commands.

$content->font($font_object, $size)

    # Example
    my $pdf = PDF::API2->new();
    my $font = $pdf->corefont('Helvetica');
    $content->font($font, 12);

Sets the font and font size.

Text-Positioning

Note: There is a very good chance that these commands will be replaced in a future release.

$content->distance($dx, $dy)

Moves to the start of the next line, offset by the given amounts, which are both required.

$content->cr($vertical_offset)

If passed with an argument, moves to the start of the next line, offset by the given value.

If passed without an argument, moves to the start of the next line.

Note that this is equivalent to a carriage return plus line feed. To get just a carriage return, pass zero as the argument.

$content->nl

Moves to the start of the next line.

($tx, $ty) = $content->textpos()

Gets the current estimated text position.

Note: This does not affect the PDF in any way.

Text-Showing

$width = $content->text($text, %options)

Adds text to the page.

Options:

-indent

Indents the text by the number of points.

-underline => 'auto'

-underline => $distance

-underline => [$distance, $thickness, ...]

Underlines the text. $distance is the number of units beneath the baseline, and $thickness is the width of the line.

Multiple underlines can be made by passing several distances and thicknesses.

$content->text_center($text)

As text, but centered on the current point.

$txt->text_right $text, %options

As text, but right-aligned to the current point.

$width = $txt->advancewidth($string, %text_state)

Returns the width of the string based on all currently set text-state attributes. These can optionally be overridden.

Advanced Methods

$content->add @content

Add raw content to the PDF stream. You will generally want to use the other methods in this class instead.

$content->compressFlate

Marks content for compression on output. This is done automatically in nearly all cases, so you shouldn't need to call this yourself.

$content->textstart

Starts a text object. You will likely want to use the text method instead.

$content->textend

Ends a text object.