Original Author Paul Laughton, 2011
Page 163
De Re BASIC!
Gr.line <obj_nvar>, x1, y1, x2, y2
Creates a line object. The line will start at (x1,y1) and end at (x2,y2). The <obj_nvar> returns the Object
List object number for this line. This object will not be visible until the Gr.render command is called.
The thinnest horizontal lines and vertical lines are drawn with Gr.set.stroke 0. These lines will be two
pixels wide if AntiAlias is on. Turn AntiAlias off to draw single-pixel wide horizontal and vertical lines.
The Gr.modify parameters for Gr.line are: "x1", "y1", "x2" and "y2".
Gr.rect <ob_nvar>, left, top, right, bottom
Creates a rectangle object. The rectangle will be located within the bounds of the parameters. The
rectangle will or will not be filled depending upon the Gr.color style parameter. The <obj_nvar> returns
the Object List object number for this rectangle. This object will not be visible until the Gr.render
command is called.
The Gr.modify parameters for Gr.rect are: "left", "top", "right" and "bottom".
Gr.oval <obj_nvar>, left, top, right, bottom
Creates an oval-shaped object. The oval will be located within the bounds of the parameters. The oval
will or will not be filled depending upon the Gr.color style parameter. The <obj_nvar> returns the Object
List object number for this oval. This object will not be visible until the Gr.render command is called.
The Gr.modify parameters for Gr.oval are: "left", "top", "right" and "bottom".
Gr.arc <obj_nvar>, left, top, right, bottom, start_angle, sweep_angle, fill_mode
Creates an arc-shaped object. The arc will be created within the rectangle described by the parameters.
It will start at the specified start_angle and sweep clockwise through the specified sweep_angle. The
angle values are in degrees.
The effect of the fill_mode parameter depends on the Gr.color style parameter:
Style 0, fill_mode false: Only the arc is drawn.
Style 0, fill_mode true: The arc is drawn with lines connecting each endpoint to the center of the
bounding rectangle. The resulting closed figure is not filled.
Style non-0, fill_mode false: The endpoints of the arc are connected by a single straight line. The
resulting figure is filled.
Style non-0, fill_mode true: The arc is drawn with lines connecting each endpoint to the center of
the bounding rectangle. The resulting closed figure is filled.
The <obj_nvar> returns the Object List object number for this arc. This object will not be visible until the
Gr.render command is called.
The Gr.modify parameters for Gr.arc are: "left", "top", "right", "bottom", "start_angle", "sweep_angle"
and "fill_mode". The value for "fill_mode" is either false (0) or true (not 0).