% ASTROSYM.MAC : AstroSym (Version 1.00, May 1, 1992) - file 3 of 7
% Peter Schmitt                     eMail: a8131dal@awiuni11.bitnet
% Institute of Mathematics, University of Vienna    Vienna, Austria
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%% variables

numeric r,R,D, a,b, s,t; %H,V,

pair 
 TL,Tl,TC,Tr,TR,
 tL,tl,tC,tr,tR,
 CL,Cl,CC,Cr,CR,
 bL,bl,bC,br,bR,
 BL,Bl,BC,Br,BR;

pair BB,MM,TT, mm, LL,RR, ll,rr, HH,VV, vv,nn;

pair vP,hP, vp,hp, vd,hd; 

%%%%%%%% macros

def  PEN = pickup pencircle scaled 2P  enddef;
def SPEN = pickup pensquare scaled 2P  enddef;
def RPEN = pickup penrazor  scaled 2P  enddef;
def  Pen = pickup pencircle scaled 2p; enddef;

def corrections =
    vP:=(0,P); hP:=(P,0);
    vp:=(0,p); hp:=(p,0);
    vd:=vP-vp; hd:=hP-hp;
    enddef;

def Corners (expr lft_corr, rt_corr, bot_corr, top_corr) =
    BL := (0+lft_corr,-d+bot_corr); BR := (w-rt_corr,-d+bot_corr);
    TL := (0+lft_corr, h-top_corr); TR := (w-rt_corr, h-top_corr);
    enddef;
def corners = Corners (P,P,P,P); enddef;

def Centers (expr x_ratio,y_ratio) =
    BC:=bot x_ratio[BL,BR]; TC:=top x_ratio[TL,TR];
    CL:=lft y_ratio[BL,TL]; CR:= rt y_ratio[BR,TR]; 
    CC:=y_ratio[BC,TC];
    enddef;
def Centers (expr x_ratio,y_ratio) =
    BC:=x_ratio[BL,BR]; TC:=x_ratio[TL,TR];
    CL:=y_ratio[BL,TL]; CR:=y_ratio[BR,TR]; 
    CC:=y_ratio[BC,TC];
    enddef;
def centers = Centers (1/2,1/2); enddef;

def TOP (expr lft_ratio,rt_ratio) =
    Tl:=lft_ratio[TL,TR]; Tr:=rt_ratio[TL,TR];
    enddef;
def BOT (expr lft_ratio,rt_ratio) =
    Bl:=lft_ratio[BL,BR]; Br:=rt_ratio[BL,BR];
    enddef;
def HOR (expr lft_ratio,rt_ratio) =
    BOT(lft_ratio,rt_ratio); TOP(lft_ratio,rt_ratio);
    enddef;

def Bot (expr ratio) =
    bl:=ratio[Bl,Tl]; bC:=ratio[BC,TC]; br:=ratio[Br,Tr];
    enddef;
def Top (expr ratio) =
    tl:=ratio[Bl,Tl]; tC:=ratio[BC,TC]; tr:=ratio[Br,Tr]; 
    enddef;

def LFT (expr bot_ratio,top_ratio) =
    bL:=bot_ratio[BL,TL]; tL:=top_ratio[BL,TL]; 
    enddef;
def RT (expr bot_ratio,top_ratio) =
    bR:=bot_ratio[BR,TR]; tR:=top_ratio[BR,TR]; 
    enddef;

def Fill (expr boundary) =
    fill boundary; draw boundary;
    enddef;

def ARROW (expr base,top, breadth, lcorr,bcorr) =
    vv := top-base;
    nn := breadth*(vv rotated 90)/2;
    BB := base; TT := top; 
    LL := base+nn-lcorr*vv; RR := base-nn-lcorr*vv;
    ll := .5[base,top]+(1-bcorr)*nn/2;
    rr := .5[base,top]-(1-bcorr)*nn/2;
    enddef;

def arrow (expr base,top, breadth, lcorr,bcorr) =
    ARROW (base,top, breadth, lcorr,bcorr);
    Fill ( LL{dir angle(ll-LL)}..{dir angle(TT-ll)}TT
         & TT{dir angle(rr-TT)}..{dir angle(RR-rr)}RR
         & RR{dir angle(BB+lcorr*vv-RR)}..BB..{dir angle(LL-BB-lcorr*vv)}LL
         ..cycle );
    enddef;

def Arrow (expr base,top, breadth, lcorr,bcorr) =
    ARROW (base,top, breadth, lcorr,bcorr);
    draw LL{dir angle(ll-LL)}..{dir angle(TT-ll)}TT
       & TT{dir angle(rr-TT)}..{dir angle(RR-rr)}RR;
    draw BB--TT;
    enddef;

def cross (expr base,top, breadth, base_corr) =
    vv := (top-base-(0,base_corr));
    nn := breadth*(vv rotated 90)/2;
    BB := base; TT := top;
    MM := .5[base+(0,base_corr),top];
    LL := MM-nn; RR := MM+nn;
    draw LL--RR; draw BB--TT;
    enddef;

%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% end of ASTROSYM.MAC %%%