Topic: APLX Help : System Classes : Properties : picture
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The 'picture' property

Not implemented under Linux

An integer vector containing graphic data

Valid for: Picture, System, Chart

The picture property contains the commands which display the graphic in a Picture object. The commands are encoded in an integer vector, and comprise a PICT or JPEG image (under MacOS) or a Windows Enhanced Metafile (under Windows). You can obtain a picture vector in a number of ways. For example, you can fetch a picture from the Clipboard by reading the picture property from the System object. Under MacOS, you can also create your own PICT variable using the functions in the QUICKDRAW workspace. Under Windows, you can read a metafile (.emf) from disk, using ⎕NREAD to convert it to an integer vector (conversion type 2).

Generally, pictures look best if they are displayed at this original size (or an integral multiple of the original size). You can, however, change the size of the picture to stretch or compress it, but to do this you must change the size after setting the picture property.

For the System object, the picture property represents a graphic image on the Clipboard. Reading the picture property returns an integer vector representing the picture currently in the Clipboard, or an empty vector if there is no picture in the Clipboard. Writing an integer vector to the System picture property places a picture on the Clipboard. The data written must be a valid graphic, i.e. a PICT or JPEG image under MacOS, or a metafile under Windows.

This Windows example creates a picture object, and displays a metafile image from disk. It then reads the picture property and places it on the Clipboard:

      MYWIN←'⎕' ⎕NEW 'Window'
      MYWIN.PIC.New 'Picture'
      FILE←'C:\Program Files\Microsoft Works\workscor\j0160036.wmf'
      '#' ⎕WI 'picture' METAFILE 

For a Chart object, the picture property is read-only. It contains the drawing commands (vector graphics) which will reproduce the chart on the current platform.

See also the bitmap property, which allows you to retrieve or set an image as an array of pixel color values.

Topic: APLX Help : System Classes : Properties : picture
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