xfpolys

fill a set of polygons

Calling Sequence

xfpolys(xpols,ypols,[fill])

Arguments

:xpols,ypols matrices of the same size (p,n) (points of the polygons). : :fill vector of size n or of size (p,n) :

Description

xfpolys fills a set of polygons of the same size defined by the two matrices xpols and ypols. The coordinates of each polygon are stored in a column of xpols and ypols.

The polygons may be filled with a given color (flat) or painted with interpolated (shaded) colors.

:flat color painting In this case fill should be a vector of size n. The pattern for filling polygon number i is given by fill(i):

• if fill(i)<0, the polygon is filled with pattern id -fill(i).
• if fill(i)=0, the polygon is drawn with the current dash style (or current color) and not filled.
• if fill(i)>0, the polygon is filled with pattern id fill(i). Then its contour is drawn with the current dash (or color) and closed if necessary.

: :interpolated color painting In this case fill should be a matrix

with same sizes as xpols and ypols. Note that p must be equal to 3 or 4. fill(k,i) gives the color at the k`th edge of polygon `i.

:

Sample

Examples

a=`gca`_();
a.data_bounds=[0,-10;210,40];
a.foreground=`color`_('red');
x1=[0,10,20,30,20,10,0]';
y1=[15,30,30,15,0,0,15]';
xpols=[x1 x1 x1 x1];
xpols=xpols+[0,60,120,180].*.`ones`_(x1);
ypols=[y1 y1 y1 y1];
xfpolys(xpols,ypols,[-1,0,1,2])

// interpolated colors
`clf`_()
f=`gcf`_();
a=`gca`_();
a.data_bounds=[0,-10;40,30];
a.isoview='on';
x1=[0,10,20,10]';
y1=[10,0,10,20]';
c=`linspace`_(2,100,4)';
xpols=[x1 x1+20 x1+10 x1+10];
ypols=[y1 y1    y1+10 y1-10];
cols= [c c($:-1:1) c([3 4 1 2]) c]
f.color_map=`jetcolormap`_(`max`_(cols));
xfpolys(xpols,ypols,cols)

// interpolated colors
`clf`_()
f=`gcf`_();
x11=[0;20;20;0];
y11=[10;10;30;30];
c11=[10;10;30;30];
x12=x11;
y12=y11+20;
c12=[20;20;1;1];
c12=[30;30;10;10];
x21=[0;30;30;0]+22;
y21=[20;20;30;30];
c21=[20;20;30;30];
x22=x21;
y22=y21+10;
c22=[30;30;20;20];
x31=[0;40;40;0]+55;
y31=[0;0;30;30];
c31=[0;0;30;30];
x32=x31;
y32=y31+30;
c32=[30;30;0;0];
X=[x11 x12 x21 x22 x31 x32];
Y=[y11 y12 y21 y22 y31 y32];
C=([c11 c12 c21 c22 c31 c32]+1)*5;
a=`gca`_();
a.isoview='on';
a.data_bounds=[`min`_(X),`min`_(Y);`max`_(X),`max`_(Y)];
f=`gcf`_();
f.color_map=`graycolormap`_(`max`_(C));
xfpolys(X,Y,C)

See Also

• xfpoly fill a polygon
• xpoly draw a polyline or a polygon
• xpolys draw a set of polylines or polygons