10/10/03

To avoid placing an unwanted dot at the centre of the circle precede the CI command with a PU command.

10 '-- Circle --

20 WIDTH "LPT1:",255

30 LPRINT CHR$(27);"E";

40 LPRINT CHR$(27);"%0B";

50 LPRINT "IN;SP1;";

60 LPRINT "SC-75,75,-75,75,1;"

70LPRINT "PA0,0;LT;CI5;LT0;CI-12;"

80LPRINT "LT1;CI19;LT2;CI-26;"

90LPRINT "LT3;CI33;LT4;CI-40;"

100LPRINT "LT5;CI47;LT6;CI54;"

110LPRINT CHR$(27);"%0A";

120LPRINT CHR$(27); "E";

130END

<Sample 30>

BR - Bezier relative

BR [ X1, Y1, X2, Y2, X3, Y3 . . . [X1, Y1, X2, Y2, X3, Y3]] [;]

X1, X2, X3 ; X coordinate of the second (X1), third (X2), and forth (X3) control point

Y1, Y2, Y3 ; Y coordinate of the second (Y1), third (Y2), and forth (Y3) control point

Coordinates are relative values in current units.

• Using the current pen position as the starting point, the bezier curve is geometrically drawn referring to the

other three points. The start point of the curve is at (X0,Y0), and the curve is tangential to the line from (X0, Y0) to (X1, Y1) at that point, and it leaves the point in that direction. The end point of the curve is at (X3,Y3), and the curve is tangential to the line from (X2,Y2) to (X3,Y3).

After execution of this command the cursor position is at the end of the bezier curve.

When drawing a bezier curve is repeated, the last (fourth) control point of the first curve is used as the first control point for the second curve.

Plotting takes place only when the pen is down.

If the command is invoked with the pen up, plotting is not performed, but the cursor position moves to

 

what would have been the plot end point.

If the curve extends to the outside of the soft/hard clip limit, it is clipped.

This command can only be used in polygon mode.

BZ - Bezier absolute

BZ [ X1, Y1, X2, Y2, X3, Y3 . . . [X1, Y1, X2, Y2, X3, Y3]] [;]

X1, X2, X3 ; X coordinate of the second (X1), third (X2), and forth (X3) control point

Y1, Y2, Y3 ; Y coordinate of the second (Y1), third (Y2), and forth (Y3) control point

Coordinates are absolute values in current units.

• Using the current pen position as the starting point, the bezier curve is geometrically drawn referring to the

other three points. The start point of the curve is at (X0,Y0), and the curve is tangential to the line from (X0, Y0) to (X1, Y1) at that point, and it leaves the point in that direction. The end point of the curve is at (X3,Y3), and the curve is tangential to the line from (X2,Y2) to (X3,Y3).

After execution of this command the cursor position is at the end of the bezier curve.

When drawing a bezier curve is repeated, the last (fourth) control point of the first curve is used as the first control point of the second curve.

Plotting takes place only when the pen is down.

If the command is invoked with the pen up, plotting is not performed, but the cursor position moves to

 

what would have been the plot end point.

If the curve extends to the outside of the soft/hard clip limit, it is clipped.

This command can only be used in polygon mode.

CHAPTER 4 HP-GL/2 - 24

Page 164
Image 164
Homelite HL-1270N, HL-P2500 BR Bezier relative, BR X1, Y1, X2, Y2, X3, Y3 . . . X1, Y1, X2, Y2, X3, Y3, BZ Bezier absolute