Documentation | InterfaceKit | PictureCallbacks

SYNOPSIS

# define MyPlayer class

my $player = MyPlayer->new();

$picture->Play($player);

# define MyPlayer class

player = MyPlayer->new()

picture.Play(player)

DESCRIPTION

Picture.Play allows you to translate a Picture into some other format; for example, Haiku's app server translate the stored instructions into pixels on the screen. However, you could also use it to translate a Picture into an SVG image, or any other image format.

The C++ version of Play takes a data pointer and an array of callback functions; the bindings version takes an object and the glue code calls methods on that object.

A callback object must provide the methods described below. As a convenience, a base object is provided, allowing you to inherit empty versions of methods you don't want to support.

package MyPicturePlayer;
our @ISA = qw(HaikuR1::PictureCallbacks);

sub new {
    my ($class, $data) = @_;
    my $self = bless { data => $data }, $class;
    return self;
}

# override supported methods here

from HaikuR1.InterfaceKit import PictureCallbacks
class MyPicturePlayer(PictureCallbacks):

def __new__(self, data):
    self.data = data
    return self

# override supported methods here

Inheriting from the base object is not required, but in that case you must supply all the methods listed below or you program will crash if the Picture contains an operation you do not support.

METHODS

Arcs

StrokeArc

FillArc

StrokeArc($center, $radii, $startTheta, $arcTheta);
FillArc($center, $radii, $startTheta, $arcTheta);

StrokeArc(center, radii, startTheta, arcTheta)
FillArc(center, radii, startTheta, arcTheta)

• center

  A Point, the center of the ellipse that defines the arc.

• radii

  A Point, the horizontal and vertical radii of the ellipses that form the rounded corners.

• startTheta, arcTheta

  Floating point numbers, the span in degrees along which the arc will travel (i.e., start angle plus arc angle equals end angle)

Bezier curves

StrokeBezier

FillBezier

StrokeBezier($control);
FillBezier($control);

StrokeBezier(control)
FillBezier(control)

• control

  A native list of four control Points.

Clipping

SetClippingRects

ClipToPicture

SetClippingRects($rects);
ClipToPicture($picture, $origin, $clipToInverse);

SetClippingRects(rects)
ClipToPicture(picture, origin, clipToInverse)

• rects

  A native list of Rects.

• picture

  A Picture.

• origin

  A Point, where the clipping should begin.

• clipToInverse

  A boolean, true if the inverse should be clipped.

Colors

SetForeColor

SetBackColor

SetForeColor($color);
SetBackColor($color);

SetForeColor(color)
SetBackColor(color)

• color

  An rgb_color.

Drawing modes

SetDrawingMode

SetLineMode

SetBlendingMode

SetDrawingMode($mode);
SetLineMode($capMode, $joinMode, $miterLimit);
SetBlendingMode($alphaSrcMode, $alphaFncMode);

SetDrawingMode(mode)
SetLineMode(capMode, joinMode, miterLimit)
SetBlendingMode(alphaSrcMode, alphaFncMode)

• mode

  An integer, one of the drawing mode constants.

• capMode

  One of the line cap mode constants.

• joinMode

  One of the line join mode constants.

• miterLimit

  A floating point number.

• alphaSrcMode

  An integer, one of the source alpha constants.

• alphaFncMode

  An integer, one of the alpha function constants.

Ellipses

StrokeEllipse

FillEllipse

StrokeEllipse($center, $radii);
FillEllipse($center, $radii);

StrokeEllipse(center, radii)
FillEllipse(center, radii)

• center

  A Point, the center of the ellipse.

• radii

  A Point, the horizontal and vertical radii of the ellipses that form the rounded corners.

Fonts

SetFontFamily

SetFontStyle

SetFontSpacing

SetFontSize

SetFontRotate

SetFontEncoding

SetFontFlags

SetFontShear

SetFontFace

SetFontFamily($family);
SetFontStyle($style);
SetFontSpacing($spacing);
SetFontSize($size);
SetFontRotate($rotation);
SetFontEncoding($encoding);
SetFontFlags($flags);
SetFontShear($shear);
SetFontFace($face);

SetFontFamily(family)
SetFontStyle(style)
SetFontSpacing(spacing)
SetFontSize(size)
SetFontRotate(rotation)
SetFontEncoding(encoding)
SetFontFlags(flags)
SetFontShear(shear)
SetFontFace(face)

• family

  A string, the family name.

• style

  A string, the style name.

• spacing

  An integer, one of the font spacing constants.

• size

  A floating point number, the font size in points.

• rotation

  A floating point number, the font rotation in degrees.

• encoding

  An integer, one of the font encoding constants.

• flags

  An integer, a combination of font flags.

• shear

  A floating point number, the font shear in degrees; must be between 45 and 135.

• face

  An integer, one of the font face constants.

Lines

StrokeLine

StrokeLine($start, $end);

StrokeLine(start, end)

• start, end

  Points, the endpoints of the line.

Origin

SetOrigin

SetOrigin($point);

SetOrigin(point)

• point

  A Point, the new origin.

Pens

MovePenBy

SetPenLocation

SetPenSize

SetStipplePattern

MovePenBy($delta);
SetPenLocation($point);
SetPenSize($size);
SetStipplePattern($pattern);

MovePenBy(delta)
SetPenLocation(point)
SetPenSize(size)
SetStipplePattern(pattern)

• delta

  A Point, the difference in the x and y coordinates.

• point

  A Point, the new location.

• size

  A floating point number.

• pattern

  The pattern the pen will draw with.

Pictures

DrawPicture

DrawPicture($where, $picture);

DrawPicture(where, picture)

• where

  A Point, the location where drawing should begin.

• picture

  A Picture.

Pixels

DrawPixels

DrawPixels($src, $dest, $width, $height, $bytesPerRow, $pixelFormat, $flags, $data);

DrawPixels(src, dest, width, height, bytesPerRow, pixelFormat, flags, data)

• src, dest

  Rects, the source coordinates (in data) and the destination coordinates (in the target).

• width, height

  Integers, the width and height of the image in data.

• bytesPerRow

  An integer, the number of bytes per row in data.

• pixelFormat

  An integer, one of the color space constants.

• flags

  An integer combination of bitmap drawing options.

• data

  The raw pixel data.

Polygons

StrokePolygon

FillPolygon

StrokePolygon($points, $isClosed);
FillPolygon($points, $isClosed);

StrokePolygon(points, isClosed)
FillPolygon(points, isClosed)

Called when ...

• points

  A native list of Points.

• isClosed

  A boolean, true if the polygon is closed (i.e., a line should be drawn from the final point back to the first point).

Rectangles

StrokeRect

FillRect

StrokeRoundRect

FillRoundRect

StrokeRect($rect);
FillRect($rect);
StrokeRoundRect($rect, $radii);
FillRoundRect($rect, $radii);

StrokeRect(rect)
FillRect(rect)
StrokeRoundRect(rect, radii)
FillRoundRect(rect, radii)

• rect

  A Rect.

• radii

  A Point, the horizontal and vertical radii of the ellipses that form the rounded corners.

Scale

SetScale

SetScale($scale);

SetScale(scale)

• scale

  A floating point number.

Shapes

StrokeShape

FillShape

StrokeShape($shape);
FillShape($shape);

StrokeShape(shape)
FillShape(shape)

• shape

  A Shape.

Strings

DrawString

DrawString($string, $deltax, $deltay);

DrawString(string, deltax, deltay)

• string

  The string to draw.

• deltax, deltay

  Floating point numbers, the horizontal and vertical offsets.

State

PushState

PopState

EnterStateChange

ExitStateChange

EnterFontState

ExitFontState