pswiggle.psplot.lib

来自「su 的源代码库」· LIB 代码 · 共 44 行

PSWIGGLE - draw wiggle-trace with (optional) area-fill via PostScript

psWiggle  draw wiggle-trace with (optional) area-fill via PostScript

Function Prototype:
void psWiggle (int n, float z[], float zmin, float zmax, float zbase,
	float yzmin, float yzmax, float xfirst, float xlast, int fill);

Inputs:
n		number of samples to draw
z		array to draw
zmin		z values below zmin will be clipped
zmax		z values above zmax will be clipped
zbase		z values between zbase and either zmin or zmax will be filled
yzmin		y-coordinate corresponding to zmin
yzmax		y-coordinate corresponding to zmax
xfirst		x-coordinate corresponding to z[0]
xlast		x-coordinate corresponding to z[n-1]
fill		= 0 for no fill
			  > 0 for fill between zbase and zmax
			  < 0 for fill between zbase and zmin
		+2 for fill solid between zbase and zmax grey between zbase and zmin
		-2 for fill solid between zbase and zmin grey between zbase and zmax
		SHADING: 2<= abs(fill) <=5   abs(fill)=2 light grey  abs(fill)=5 black

NOTES:
psWiggle reduces PostScript output by eliminating linetos when
z values are essentially constant.  The tolerance for detecting 
constant" z values is ZEPS*(zmax-zmin), where ZEPS is a fraction 
defined below.

A more complete optimization would eliminate all connected line 
segments that are essentially colinear.

psWiggle breaks up the wiggle into segments that can be drawn
without exceeding the PostScript pathlimit.

Author:  Dave Hale, Colorado School of Mines, 07/03/89
Modified:  Craig Artley, Colorado School of Mines, 04/13/92
           Corrected dead trace bug.  Now the last point of each segment
           is guaranteed to be drawn.
MODIFIED: Paul Michaels, Boise State University, 29 December 2000
           added fill=+/-2 option of solid/grey color scheme