TVCRS Procedure

Manipulates the cursor within a displayed image, allowing it to be enabled and disabled, as well as positioned.

TVCRS [, on_off]

TVCRS [, x, y]

on_off (optional) Specifies whether the cursor should be on or off. If present and nonzero, enables the cursor. If zero or not specified, disables the cursor.

x (optional) The column to which the cursor will be positioned.

y (optional) The row to which the cursor will be positioned.

Centimeters If present, specifies that all position values are in centimeters from the origin.

Data If present and nonzero, specifies that the cursor position is in data coordinates.

Device If present and nonzero, specifies that the cursor position is in device coordinates.

Hide If present and nonzero, causes a disabled cursor to always be blanked out.

By default, disabling the cursor works differently for window systems than for other devices. For window systems, the cursor is restored to the standard cursor used for non-PV-WAVE windows (and remains visible), while for other devices it is completely blanked out.

Inches If present, specifies that all position values are in inches from the origin.

Normal If present and nonzero, specifies that the cursor position is in normalized coordinates.

T3d If present, indicates that the generalized transformation matrix in !P.T is to be used. (For a description of !P.T, see the Save plotting keyword in Chapter 3, Graphics and Plotting Keywords.)

If not present, the user-supplied coordinates are simply scaled to screen coordinates.

Z The z position. The value of z is of use only if the three-dimensional transformation is in effect via the T3d keyword.

Normally, the cursor is disabled and is not visible. Using TVCRS with one parameter allows the cursor to be enabled or disabled, while using TVCRS with two parameters enables the cursor and places it on pixel location (X, Y).

To enable the image display cursor and position it at device coordinate, use the following command:

TVCRS, 100, 100

To enable the image display cursor and position it at data coordinate, use the following command:

TVCRS, 0.5, 3.2, /Data

To disable and hide the image display cursor, use the following command:

TVCRS, /Hide_Cursor

To enable the image display cursor but not set the cursor position, use the following command:

TVCRS, 1

CURSOR, TVRD

For more information, see Image Display Routines: TV and TVSCL in Chapter 6 of the PV-WAVE User's Guide.