Creating Graphics

Drawing Graphics Items

An item can be redrawn or modi￿ed whenever it is active. Only one item can be active at a time. The active item is determined by the last executed IT command. The following table shows commands that modify items:

Commands that Modify Items

 

Description

 

Command

 

 

 

Blank item.

 

VW OFF (view item o￿)

Redraw item.

 

VW ON (view item on)

O￿set item position.

OR

(origin)

Change item

shape.

TP

(tablet pointer)

Stop displa y

of item and delete from memory .

DELETE (delete item)

 

 

 

 

In the following example, item 1 is activated, blanked, and then redrawn. Notice that it is not necessary to execute the PD command or reexecute the individual graphics commands assigned to the item.

160

OUTPUT

723;"IT

1;"

Activate item.

170

OUTPUT

723;"VW

OFF;"

Blank item.

180

OUTPUT

723;"WAIT 5;"

Pause program to view display .

190

OUTPUT

723;"VW

ON;"

Redraw item.

Use the OR command to move an item on the display.

160

OUTPUT

723;"IT

1;"

Activate item 1.

170

OUTPUT

723;"OR

500,500;"

O￿set item 1.

Moving Graphics Items

5-13