HP Pcl 5 Manual

							ENPattern Transparency for Rectangular Area Fill 14-11
Pattern Transparency for Rectangular Area Fill 
Pattern transparency, described in Chapter 13, under “Pattern 
Transparency Mode Command,” affects how a pattern is applied 
to the rectangular fill area. Rectangular areas are special case 
images for transparency mode. The pattern and pattern type 
are selected by the Pattern ID command (
E
C*c#G) and the Fill 
Rectangular Area 
(E
C*c#P) command (described earlier in this 
chapter).
NoteSource transparency has no effect on the rectangular fill area since 
the rectangular area is viewed as all 1’s (solid black) source image.
When applying a pattern (area fill) to the rectangular area, the usual 
transparency mode settings apply. The pattern transparency mode 
determines the effect white pixels of the pattern have on the 
destination for value fields 0 (black fill), 2 (shaded fill), 3 (cross-hatch 
fill), or 5 (current pattern fill) of the Fill Rectangular Area command.
The “0” bits of the area fill are either applied (opaque) or ignored 
(transparent) based on the transparency mode setting (see Figure 
14-3). When a value field of 1 (white fill) is used, pattern transparency 
mode is always treated as if it were opaque.
The effect of transparency modes on rectangular areas is illustrated 
in Figure 14-3. In both examples, the source transparency mode is 
opaque regardless of the actual setting. In the first example, the 
pattern transparency mode is transparent; the white pixels in the 
pattern are not applied to the destination, so that the pattern is visible 
in only two quadrants of the destination. In the second example, the 
pattern transparency mode is opaque, and the pattern is visible in the 
entire rectangular area. 
						

							14-12   PCL Rectangular Area Fill GraphicsEN
Figure 14-3 Effect of Transparency Modes on Rectangular Areas 
						

							ENRectangular Area Fill Examples 14-13
Rectangular Area Fill Examples 
This section shows example usage of area fill commands to print 
pre-defined patterns as well as user-defined patterns.
Pre-defined Pattern Examples 
Solid Fill (Black/White) 
To print a 900 by 1500 Unit black rule (3 inches by 5 inches at 300 
units-per-inch), then white fill a small area inside the black rectangle, 
perform the following steps.
11. Position the cursor:
E
C*p300x400Y 
This moves the cursor to PCL Unit position (300, 400) within 
the PCL coordinate system.
22. Specify the width of the rule:
E
C*c900A 
This sets the rule width to 900 PCL Units (3 inches at 300 
units-per-inch).
33. Specify the height of the rule:
E
C*c1500B 
This sets the rule height to 1500 PCL Units (5 inches at 300 
units-per-inch).
44. Print the rule:
E
C*c0P 
 This example prints a black filled rectangular area.
55. Position the cursor inside the rectangular area:
E
C*p600x700Y 
						

							14-14   PCL Rectangular Area Fill GraphicsEN
66. Specify the width and height for the smaller white fill 
rectangular area:
E
C*c300a600B
77. Select the white fill and print.
E
C*c1P
Figure 14-4 Solid Fill Example
Shaded Fill 
To print a 900 by 1500 Unit 25% shaded rectangle (3 inches by 5 
inches at 300 units-per-inch), perform the following steps.
1Position the cursor:
E
C*p300x400Y 
This moves the cursor to PCL Unit position (300, 400) within 
the PCL coordinate system.
2Specify the width of the rectangle:
E
C*c900A  
This sets the rectangle width to 900 PCL Units (3 Inches at 
300 units-per-inch). 
						

							ENRectangular Area Fill Examples 14-15 3Specify the height of the rectangle:
E
C*c1500B 
This sets the rectangle to 1500 PCL Units (5 inches at 300 
units-per-inch).
4Specify the Pattern ID:
E
C*c25G 
This sets the Pattern ID to 25.
1Print the rectangular shaded area:
E
C*c2P 
 This example prints the following:
Figure 14-5 Shaded Fill Example 
						

							14-16   PCL Rectangular Area Fill GraphicsEN
Cross-hatch Fill 
To print a 900 by 1500 Unit rectangular area (3 inches by 5 inches 
at 300 units-per-inch), filled with a horizontal cross-hatch pattern, 
perform the following steps:
1. Position the cursor:
E
C*p300x400Y 
Moves the cursor to PCL Unit position (300,400) within the PCL 
coordinate systems.
2. Specify the width of the rectangle:
E
C*c900A 
Sets the rectangle width to 900 PCL Units (3 inches at 300 
units-per-inch).
3. Specify the height of the rectangle:
E
C*c1500B  
Sets the rectangle height to 1500 PCL Units (5 inches at 300 
units-per-inch).
4. Specify the Pattern ID:
E
C*c1G 
 Sets the Pattern ID to 1.
5. Print the rectangular pattern-filled area:
E
C*c3P  
						

							ENRectangular Area Fill Examples 14-17  This example prints the following:
Figure 14-6 Patterned Fill Example
User-defined Pattern Example  
This example shows how to print a user-defined pattern which has 
already been downloaded to the printer. For this example we will print 
the pattern of triangles which was downloaded in the example in 
Chapter 13, under “User-Defined Pattern Command.”
The following commands define a 600 PCL Unit square rectangular 
area, select ID number 3, and print the user-defined pattern 
associated with that ID number.
1Position the cursor:
E
C*p300x400Y 
Moves the cursor to PCL Unit position (300,400) within the 
PCL coordinate systems.
2Specify the width and height of the rectangle:
E
C*c600a600B  
						

							14-18   PCL Rectangular Area Fill GraphicsEN
Sets the rectangle width and height both to 600 PCL Units (2 
x 2 inches at 300 Units/inch).
3Specify the Pattern ID:
E
C*c3G 
 Sets the Pattern ID to 3.
4Print the user-defined pattern-filled area:
E
C*c5P 
 This example prints as shown in Figure 14-7.
Figure 14-7 User-Defined Pattern Fill Example 
						

							ENIntroduction  15-1
15
Raster Graphics 
Introduction 
A raster image is an image composed of dots. Pictures in 
newspapers or on television screens (also, a page printed by 
this printer) are examples of raster images. The PCL language 
includes commands for printing raster graphic images. These 
commands enable the LaserJet printer to receive binary data 
and print it as a raster image.
The binary data used to create a raster image is divided into dot 
rows: a row describes a one-dot-high strip of the image. Each dot 
position within a row is represented by a binary data bit. If a bit in 
a row is set to one, a dot is printed; if the bit is set to zero, no dot 
is printed for that position. A dot row of raster image data is 
transferred to the printer as a string of bytes containing a 
dot-per-bit representation of the row.
Figure 15-1 Binary Raster Data
Since it takes a considerable amount of data to create even a 
small raster image, several methods are provided to reduce the 
amount of data needed to define an image. (Note, that the above 
illustration creates a rectangle 0.013 by 0.027 inches; a binary 
“1“ = 1 dot = 1/300 inch.) These reduction techniques include  
						

							15-2   Raster GraphicsEN
several binary data compression methods, and additional reduction 
techniques associated with the raster area feature (see Figure 15-2).
Figure 15-2 Raster Area
Data compression methods include: run-length encoding, tagged 
image file format (TIFF), delta row, and adaptive compression. These 
techniques are described in detail later in this section, under the Set 
Compression Method command.
In addition to the compression methods, the raster area feature 
provides some other raster reduction techniques which utilize a 
defined raster area. The raster area is defined by a width and height 
which are set using the Raster Width and the Raster Height 
commands.
Zeroed rows at the top and within the raster image can be eliminated 
by using the Y-offset feature. Y-Offset identifies how many rows to 
skip (zero fill). The Y-offset command specifies the Y-offset or number 
of rows for the printer to fill with zeroed rows. This provides a 
reduction in data for increased efficiency.
Trailing zeroed full rows at the end of the raster image need not be 
sent. The printer automatically fills in any unsent zeroed rows from 
the end of the raster image (last raster row with any “1”s) to the 
bottom of the raster area.