Kyocera FS 1028DP User Manual

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Two Lines 
The preceding example illustrated construction of a path between points specified in 
terms of absolute coordinates. The following program draws two lines, using both abso-
lute coordinate specification and a new method: relative coordinate specification. 
!R! RES; NEWP;
PMZP 1, 1;
PDZP 2, 3;
PMRP .5, -1;
PDRP -1, -1;
SPD 0.04;
STRK;
PAGE;
EXIT; 
Figure 2. 15.  Drawing Two Lines   
The first four lines of this program are  identical to the preceding example. Line 1...

Chapter 2 Graphics Tutorial
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Line Ends 
The line end type determines how PRESCRIBE renders the ends of lines when they are 
stroked onto the page. PRESCRIBE provides three kinds of line ends. These include: 
Figure 2. 16.  Line Ends 
The default line end type is butt caps. You can  switch from the current line end type to 
any of the other types with the SCAP command. This command uses the following for-
mat: 
SCAP line-cap mode ; 
Va l u e s  f o r   line-cap mode  include: 
1 (for square caps)
2...

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stroking the path. PRESCRIBE refers to the line cap type when the current path is 
stroked onto the page, rather than while the pa th is being constructed. Therefore, the pro-
gram above renders the line with round caps rather than square ones. 
Line Joins 
When a path consists of multiple connected  line segments, the manner in which they are 
stroked onto the page depends on the current  line join type. 
PRESCRIBE provides four types of  line joins. These are called beveled,...

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Figure 2. 19.  Miter Limit 
Miter limit = maximum ratio of 
L/w = 1/sin (a/2)
If the angle at which lines join is such that th is limit is exceeded, the lines are joined with 
a beveled join, rather than a mitered one. 
The purpose of the miter limit is to prevent objectionably long spikes when lines join at 
small angles. The default miter limit is 10, which results in beveled joins at angles of less 
than about 11.5 degrees. 
You can set any desired miter limit with the...

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The following program illustrates use of this command. 
!R! RES;UNIT C; CMNT Sets unit to cm;
NEWP; CMNT Starts new path;
SPD .5; CMNT Sets line width to .5 cm;
PMZP 2, 2;
PDZP 4, 4;
DPAT 5;
STRK;
PAGE;
EXIT; 
Figure 2. 20.  Printout of the DPAT Example   
In this program, the DPAT command selects the dash pattern with which the line is 
stroked. 
Predefined dash patterns are  selected by specifying values  from 1 to 10 for pattern-num-
ber. (A value of 1 specifies solid lines.)...

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Figure 2. 21.  Printout of the SDP Example   
The SDP command on line 3 defines a dashed pattern consisting of two lengths of black, 
two lengths of white, five lengths of black, and two lengths of white. On line 11, the 
DPAT command selects this pattern for stroking. The path defined by the PMZP (Path, 
Move to Zero-relative Position) and PDZP (Path, Draw to Zero-relative Position) com-
mands is stroked using this pattern, with a result as shown in the figure above....

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Figure 2. 22.  Printout of the PARC Example   
After the arc is drawn, the cursor is located at the end of the arc. 
If you wish to eliminate the st raight line segment in the above example, leaving only the 
arc, the cursor position must be moved in advance to the position at which drawing of the 
arc begins. This is shown in the following example, in which the cursor is moved to the 
coordinates as specified by the PMRA (Pat h, Move to Relative position specified by 
Angle)...

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Figure 2. 24.  Printout of a Circle Made with PMRA 
  
Drawing Complex Curves 
PRESCRIBE also provides a second curve-dr awing operator for constructing complex 
curves that are referred to as  Bézier curve segments. The PCRP (Path, Curve to Relative 
Position) uses the following format.
PCRP x1 , y1, x2, y2 , x3, y3; 
Figure 2. 25.  Bézier Curves 
A Bézier curve segment is one that is geomet rically defined by a starting point (the cur-
sor’s current position), two...

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The curve leaves the current position in the direction of x1, y1, and is tangent to the line 
between the current position and  x1, y1. It bends towards  x2, y2, then to  x3, y3, and at the 
end point, is tangent to the line between x2, y2 and x3, y3. The curve is always entirely 
enclosed by the complex quadrilateral defined by the starting point,  x1, y1, x2, y2, and 
x3, y3.  
See the following examples: 
!R! RES; UNIT C; NEWP; SPD .1; PMZP 3, 3;
PCRP 4, 2, 5, 1.5, 6, 1.8;...

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!R! RES; UNIT C; NEWP; SPD .1;PMZP 3, 4;
PCRP 4, 2, 5, 4, 6, 2;
STRK;
PAGE;
EXIT; 
Figure 2. 28.  Third PCRP Example   
Setting the Flatness of Curves 
When PRESCRIBE renders any curve, it actuall y converts the curve to a series of con-
nected straight line segments. The length of these line segments is referred to as a curve’s 
flatness . You can change the degree of flatness  with the FLAT (set FLATness) command. 
The default flatness is 1 (dot). Setting smaller values...