# Mnemonics

'IMAGE' | Define a Graphics Group

GUI Display/Printer

## Formats

1. | Define Graphics Group: | 'IMAGE' ("group$")
2. | Delete Graphics Group: | 'IMAGE'(DELETE group$)
3. | Hide/Show Group: | 'IMAGE'({ENABLE | DISABLE} group$)

Where:

group$ | Graphics group name. String expression. If you omit this when defining a group, the default is "" (null).

## Description

PxPlus normally queues all mnemonics since the last 'CS' (to supply information in case Windows needs to redraw the screen). In consequence, if you are constantly creating graphics, you can exhaust system resources. 'IMAGE' helps to circumvent this potential problem.

When 'IMAGE' is used to define and control the display of graphics groups, all graphical mnemonics following the 'IMAGE' mnemonic will be grouped. You can then disable the group to remove it from view and enable the group to make it visible.

'IMAGE' groups are always drawn on the screen in the order in which they are first declared, starting with the default 'IMAGE' group of "". This means that new 'IMAGE' groups will be drawn on top of the default group and potentially overlap any previously defined 'IMAGE' groups.

The DELETE option can be used to destroy the group and return resources to the system.

#### Note:
When drawing graphical objects, each object will be laid one on top of the next. Use the 'IMAGE' mnemonic to erase previous graphics instead. This reduces the consumption of Windows resources and helps prevent flicker during a repaint operation.

## Example

! Display 'IMAGE' groups
print 'CS'
FACE$='pen'(1,4,3)+'arc'(800,200,105,1,1,360)
NOSE$='pen'(1,4,0)+'line'(800,205,800,235)
LEFT_EYE$='pen'(1,2,4)+'fill'(1,0)+'circle'(765,170,20)
RIGHT_EYE$='pen'(1,1,0)+'fill'(1,0)+'circle'(835,170,18,1)
WINK$='pen'(1,4,0)+'arc'(765,170,20,1,165,15)+'fill'(1,0)+'circle'(775,170,10)
SMILE$='pen'(1,3,0)+'arc'(800,230,45,1,190,350)
print 'image'("HAPPY"),FACE$,NOSE$,SMILE$
print 'image'("WIDE_EYED"),LEFT_EYE$+RIGHT_EYE$;
wait .5
print 'image'(disable "WIDE_EYED")
print 'image'("WINK"),WINK$,RIGHT_EYE$;
wait 1;
print 'image'(delete "WINK")
print 'image'(enable "WIDE_EYED");
wait 1
print 'image'(delete "HAPPY"),'image'(delete "WIDE_EYED")
print @(0,12);
list
print WINK$,RIGHT_EYE$,NOSE$,SMILE$;
end