Usage.md

Usage

A typical use of this library involves 4 steps:

1. define node and edge styles
2. define nodes
3. layout and draw nodes
4. draw edges

define node and edge styles

this step can be ignored if the default black-white style satisfies you, or a single line if you want edges to have arrows:

defaultdrawstyle=drawstyle(Arrow);

there are two global variables to control the default node style and edge style, you can overwrite them to satisfy your own needs:

defaultnodestyle=nodestyle(drawfn=FillDrawer(lightgray,black));
defaultdrawstyle=drawstyle(p=fontsize(8pt)+fontcommand("\ttfamily"), arrow=Arrow(6));

you can define your own styles if you want multiple styles:

defaultnodestyle=nodestyle(textpen=white, drawfn=FillDrawer(darkgreen,black));
nodestyle ns2=nodestyle(textpen=white, drawfn=Filler(darkgreen)+DoubleDrawer(black));
nodestyle ns3=nodestyle(drawfn=None);

define nodes

shaped nodes, (nbox can be ncircle, nellipse, nroundbox, ndiamond, nparallelogram)

node n0 = nbox("$n_0$");
node n1 = ncircle("$n_1$", ns2);

or multiple nodes of the same shape and style (nboxes, ..., nparallelograms)

node[] n = nboxes("$n_0$", "$n_1$", "$n_2$", "$n_3$", "$n_4$");
node[] n = ncircles(ns2, "$n_0$", "$n_1$", "$n_2$", "$n_3$", "$n_4$");

text nodes (node)

node n0 = node("$n_0$");
node[] n = node("$n_0$", "$n_1$", "$n_2$", "$n_3$", "$n_4$");

Label[][] strs = {
    {"$a_{0,0}$", "$\cdots$", "$a_{0,n}$"},
    {"$\vdots$", "$\ddots$", "$\vdots$"},
    {"$a_{m,0}$", "$\cdots$", "$a_{m,n}$"}};
node[][] n2d = node(strs);

node resize (setsize, setwidth, setheight):

setwidth(... nds); // automatically set to the largest width
setwidth(w=width ... nds); // set width to "w", if w=0, automatically

setheight(h ... nds);

setsize((w,h) ... nds);

// set nds total width to 10cm, with ratios of 5:1:2
setwidth(10cm, new real[]{5,1,2} ... nds);

compound nodes (npack, hpack, vpack), nodes can be firsted resized, and then layouted before packing:

hpack(h=-1 ... nds);       // do not reisze nodes
hpack(h=0 ... nds);        // nodes are set to same height
hpack(h=height, ... nds);   // nodes are set to "height" (positive)

vpack(w=<-1, 0 or width> ... nds)

symbol nodes, please refer to nodecircuit, and nodesml.

layout nodes

two global variables to control the layout properties

• relative layout: layout according to the outline of nodes

• absolute layout: layout accordng to the position of nodes

  defaultlayoutrel = true; // relative layout defaultlayoutskip = 1cm; // nodes skip

layouts (there is a global node "nodeph" as a place holder):

layout(dir ... nds);
hlayout(... nds);
vlayout(... nds);

gridlayout((rownum, colum) ... nds);
gridlayout(nds2d);

circularlayout(... nds);

centerlayout(dir, refnode ... nds);
hcenterlayout(refnode ... nds);
vcenterlayout(refnode ... nds);

set to absolute positions:

setpos(nds, positions);

flush:

flush(align ... nds); // align can be N, S, E, W

layout APIs reference:

layout(dir, skip, rel ... nds);
hlayout(skip, rel ... nds);
vlayout(skip, rel ... nds);

gridlayout((rownum, colnum), roworder, (xskip, yskip), rel ... nds);

circularlayout(radius, center, startangle, angleskip ... nds);

centerlayout(dir, refnode, skip, rel ... nds);
hcenterlayout(refnode, skip, rel ... nds);
vcenterlayout(refnode, skip, rel ... nds);

draw nodes

draw(... nds);

draw edges

draw(
        (n1--n2),
        (n1..n2),
        (n1..loop(N)),
        (n1..bend..n2),
        (n1--n2).l("label"),
        (n1--n2).l("label").style(es2),
        (n1--n2).l("label").style("autorot"),
        (n1--n2).l("label").style("leftside"),
        (n1--n2).l("label").shorten(5,5)
    );