takepic

OpenTuring

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takepicgraphics procedure

        setscreen ("graphics")
        … draw happy face in the box (0,0) to (100,100) …
        % Create buffer big enough to hold happy face
        var face : array 1 .. sizepic ( 0, 0, 100, 100 ) of int
        % Copy picture into the buffer, which is the face array
        takepic ( 0, 0, 100, 100, face )
        % Redraw the picture with its left bottom at (200,0)
        drawpic ( 200, 0, face, 0 )
Syntax   takepic (x1, y1, x2, y2 : int, var buffer : array 1 .. * of int)

Description   The takepic procedure is used to record the pixel values in a rectangle, with left bottom and right corners of (x1, y1) and (x2, y2), in the buffer array. This requires a sufficiently-large buffer (see sizepic ). The drawpic procedure is used to make copies of the recorded rectangle on the screen.

Example   After drawing a happy face, this program copies the face to a new location.

Execute  

Details   The integer values that takepic places in the buffer can be read or written (using the read and write statements). Unfortunately, if a value happens to be the pattern used to represent the uninitialized value (the largest negative number the hardware can represent) assignment (by:=) and put of the individual integer values in the buffer will fail.

The screen should be in a "graphics" mode. See the setscreen procedure for details. If the screen is not in a "graphics" mode, it will automatically be set to "graphics" mode.

Details   The drawpic, takepic, and sizepic subprograms have been made obsolete by the subprograms Pic.Draw and Pic.New of the Pic module. Users are strongly suggested to use those routines instead. The Pic module also contains subprograms to load images from files.

See also   sizepic and drawpic. See also setscreen, maxx, maxy, drawdot, drawline, drawbox, and drawoval.

See also predefined unit Pic.

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