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diff --git a/man/man3/draw.html b/man/man3/draw.html new file mode 100644 index 00000000..f90b16fc --- /dev/null +++ b/man/man3/draw.html @@ -0,0 +1,1174 @@ +<head> +<title>draw(3) - Plan 9 from User Space</title> +<meta content="text/html; charset=utf-8" http-equiv=Content-Type> +</head> +<body bgcolor=#ffffff> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=10><td> +<tr><td width=20><td> +<tr><td width=20><td><b>DRAW(3)</b><td align=right><b>DRAW(3)</b> +<tr><td width=20><td colspan=2> + <br> +<p><font size=+1><b>NAME </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image, draw, drawop, gendraw, gendrawop, drawreplxy, drawrepl, + replclipr, line, lineop, poly, polyop, fillpoly, fillpolyop, bezier, + bezierop, bezspline, bezsplineop, bezsplinepts, fillbezier, fillbezierop, + fillbezspline, fillbezsplineop, ellipse, ellipseop, fillellipse, + fillellipseop, arc, arcop, fillarc, fillarcop, icossin, icossin2, + border, string, stringop, stringn, stringnop, runestring, runestringop, + runestringn, runestringnop, stringbg, stringbgop, stringnbg, stringnbgop, + runestringbg, runestringbgop, runestringnbg, runestringnbgop, + _string, ARROW, drawsetdebug – graphics functions<br> + +</table> +<p><font size=+1><b>SYNOPSIS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>#include <u.h><br> + #include <libc.h><br> + #include <draw.h><br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + typedef<br> + struct Image<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Display *display; /* display holding data */<br> + int id; /* id of system−held Image */<br> + Rectangle r; /* rectangle in data area, local coords */<br> + Rectangle clipr; /* clipping region */<br> + ulong chan; /* pixel channel format descriptor */<br> + int depth; /* number of bits per pixel */<br> + int repl; /* flag: data replicates to tile clipr */<br> + Screen *screen; /* 0 if not a window */<br> + Image *next; /* next in list of windows */<br> + + </table> + } Image;<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + typedef enum<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + /* Porter−Duff compositing operators */<br> + Clear = 0,<br> + SinD = 8,<br> + DinS = 4,<br> + SoutD = 2,<br> + DoutS = 1,<br> + S = SinD|SoutD,<br> + SoverD = SinD|SoutD|DoutS,<br> + SatopD = SinD|DoutS,<br> + SxorD = SoutD|DoutS,<br> + D = DinS|DoutS,<br> + DoverS = DinS|DoutS|SoutD,<br> + DatopS = DinS|SoutD,<br> + DxorS = DoutS|SoutD, /* == SxorD */<br> + Ncomp = 12,<br> + + </table> + } Drawop;<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + void draw(Image *dst, Rectangle r, Image *src,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *mask, Point p)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void drawop(Image *dst, Rectangle r, Image *src,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *mask, Point p, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void gendraw(Image *dst, Rectangle r, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *mask, Point mp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void gendrawop(Image *dst, Rectangle r, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *mask, Point mp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int drawreplxy(int min, int max, int x)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Point drawrepl(Rectangle r, Point p)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + void replclipr(Image *i, int repl, Rectangle clipr)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + void line(Image *dst, Point p0, Point p1, int end0, int end1,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int radius, Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void lineop(Image *dst, Point p0, Point p1, int end0, int end1,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int radius, Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void poly(Image *dst, Point *p, int np, int end0, int end1,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int radius, Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void polyop(Image *dst, Point *p, int np, int end0, int end1,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int radius, Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void fillpoly(Image *dst, Point *p, int np, int wind,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void fillpolyop(Image *dst, Point *p, int np, int wind,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int bezier(Image *dst, Point p0, Point p1, Point p2, Point p3,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int end0, int end1, int radius, Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int bezierop(Image *dst, Point p0, Point p1, Point p2, Point p3,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int end0, int end1, int radius, Image *src, Point sp,<br> + Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int bezspline(Image *dst, Point *pt, int npt, int end0, int end1,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int radius, Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int bezsplineop(Image *dst, Point *pt, int npt, int end0, int + end1,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int radius, Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int bezsplinepts(Point *pt, int npt, Point **pp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + int fillbezier(Image *dst, Point p0, Point p1, Point p2, Point + p3,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int w, Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int fillbezierop(Image *dst, Point p0, Point p1, Point p2, Point + p3,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + int w, Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int fillbezspline(Image *dst, Point *pt, int npt, int w,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int fillbezsplineop(Image *dst, Point *pt, int npt, int w,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void ellipse(Image *dst, Point c, int a, int b, int thick,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void ellipseop(Image *dst, Point c, int a, int b, int thick,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void fillellipse(Image *dst, Point c, int a, int b,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void fillellipseop(Image *dst, Point c, int a, int b,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void arc(Image *dst, Point c, int a, int b, int thick,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp, int alpha, int phi)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void arcop(Image *dst, Point c, int a, int b, int thick,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Image *src, Point sp, int alpha, int phi, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void fillarc(Image *dst, Point c, int a, int b, Image *src,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Point sp, int alpha, int phi)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void fillarcop(Image *dst, Point c, int a, int b, Image *src,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Point sp, int alpha, int phi, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + int icossin(int deg, int *cosp, int *sinp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + int icossin2(int x, int y, int *cosp, int *sinp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + void border(Image *dst, Rectangle r, int i, Image *color, Point + sp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + Point string(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringn(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, int len)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringnop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, int len, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestring(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringn(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, int len)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringnop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, int len, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringbg(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, Image *bg, Point bgp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringbgop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, Image *bg, Point bgp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringnbg(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, int len, Image *bg, Point bgp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point stringnbgop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, char *s, int len, Image *bg, Point bgp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringbg(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, Image *bg, Point bgp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringbgop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, Image *bg, Point bgp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringnbg(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, int len, Image *bg, Point bgp)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point runestringnbgop(Image *dst, Point p, Image *src, Point sp,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Font *f, Rune *r, int len, Image *bg, Point bgp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Point _string(Image *dst, Point p, Image *src,<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Point sp, Font *f, char *s, Rune *r, int len,<br> + Rectangle clipr, Image *bg, Point bgp, Drawop op)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + void drawsetdebug(int on)<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + enum<br> + {<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + /* line ends */<br> + Endsquare = 0,<br> + Enddisc = 1,<br> + Endarrow = 2,<br> + Endmask = 0x1F<br> + + </table> + + </table> + };<br> + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + #define ARROW(a, b, c) (Endarrow|((a)<<5)|((b)<<14)|((c)<<23))<br> + </font></tt> +</table> +<p><font size=+1><b>DESCRIPTION </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + The <tt><font size=+1>Image</font></tt> type defines rectangular pictures and the methods to + draw upon them; it is also the building block for higher level + objects such as windows and fonts. In particular, a window is + represented as an <tt><font size=+1>Image</font></tt>; no special operators are needed to draw + on a window. + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + <tt><font size=+1>r</font></tt> The coordinates of the rectangle in the plane for which the <tt><font size=+1>Image</font></tt> + has defined pixel values. It should not be modified after the + image is created.<br> + <tt><font size=+1>clipr</font></tt> The clipping rectangle: operations that read or write the + image will not access pixels outside <tt><font size=+1>clipr</font></tt>. Frequently, <tt><font size=+1>clipr</font></tt> + is the same as <tt><font size=+1>r</font></tt>, but it may differ; see in particular the discussion + of <tt><font size=+1>repl</font></tt>. The clipping region may be modified dynamically using + <i>replclipr</i> (<i>q.v.</i>).<br> + <tt><font size=+1>chan</font></tt> The pixel channel format descriptor, as described in <a href="../man7/image.html"><i>image</i>(7)</a>. + The value should not be modified after the image is created.<br> + <tt><font size=+1>depth</font></tt> The number of bits per pixel in the picture; it is identically + <tt><font size=+1>chantodepth(chan)</font></tt> (see <a href="../man3/graphics.html"><i>graphics</i>(3)</a>) and is provided as a convenience. + The value should not be modified after the image is created.<br> + <tt><font size=+1>repl</font></tt> A boolean value specifying whether the image is tiled to cover + the plane when used as a source for a drawing operation. If <tt><font size=+1>repl</font></tt> + is zero, operations are restricted to the intersection of <tt><font size=+1>r</font></tt> and + <tt><font size=+1>clipr</font></tt>. If <tt><font size=+1>repl</font></tt> is set, <tt><font size=+1>r</font></tt> defines the tile to be replicated and + <tt><font size=+1>clipr</font></tt> defines the portion of the plane covered by the + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + tiling, in other words, <tt><font size=+1>r</font></tt> is replicated to cover <tt><font size=+1>clipr</font></tt>; in such + cases <tt><font size=+1>r</font></tt> and <tt><font size=+1>clipr</font></tt> are independent.<br> + For example, a replicated image with <tt><font size=+1>r</font></tt> set to ((0, 0), (1, 1)) + and <tt><font size=+1>clipr</font></tt> set to ((0, 0), (100, 100)), with the single pixel of + <tt><font size=+1>r</font></tt> set to blue, behaves identically to an image with <tt><font size=+1>r</font></tt> and <tt><font size=+1>clipr</font></tt> + both set to ((0, 0), (100, 100)) and all pixels set to blue. However, + the first image requires far less memory. The + replication flag may be modified dynamically using <i>replclipr</i> (<i>q.v.</i>). + + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + + </table> + + </table> + Most of the drawing functions come in two forms: a basic form, + and an extended form that takes an extra <tt><font size=+1>Drawop</font></tt> to specify a Porter-Duff + compositing operator to use. The basic forms assume the operator + is <tt><font size=+1>SoverD</font></tt>, which suffices for the vast majority of applications. + The extended forms are named by adding an + -<tt><font size=+1>op</font></tt> suffix to the basic form. Only the basic forms are listed + below.<br> + <tt><font size=+1>draw(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>r</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>mask</i><tt><font size=+1>,</font></tt> <i>p</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Draw</i> is the standard drawing function. Only those pixels within + the intersection of <i>dst</i><tt><font size=+1>−>r</font></tt> and <i>dst</i><tt><font size=+1>−>clipr</font></tt> will be affected; <i>draw</i> + ignores <i>dst</i><tt><font size=+1>−>repl</font></tt>. The operation proceeds as follows (this is a + description of the behavior, not the implementation):<br> + 1. If <tt><font size=+1>repl</font></tt> is set in <i>src</i> or <i>mask</i>, replicate their contents to fill + their clip rectangles.<br> + 2. Translate <i>src</i> and <i>mask</i> so <i>p</i> is aligned with <i>r</i><tt><font size=+1>.min</font></tt>.<br> + 3. Set <i>r</i> to the intersection of <i>r</i> and <i>dst</i><tt><font size=+1>−>r</font></tt>.<br> + 4. Intersect <i>r</i> with <i>src</i><tt><font size=+1>−>clipr</font></tt>. If <i>src</i><tt><font size=+1>−>repl</font></tt> is false, also intersect + <i>r</i> with <i>src</i><tt><font size=+1>−>r</font></tt>.<br> + 5. Intersect <i>r</i> with <i>mask</i><tt><font size=+1>−>clipr</font></tt>. If <i>mask</i><tt><font size=+1>−>repl</font></tt> is false, also intersect + <i>r</i> with <i>mask</i><tt><font size=+1>−>r</font></tt>.<br> + 6. For each location in <i>r</i>, combine the <i>dst</i> pixel with the <i>src</i> pixel + using the alpha value corresponding to the <i>mask</i> pixel. If the + <i>mask</i> has an explicit alpha channel, the alpha value corresponding + to the <i>mask</i> pixel is simply that pixel’s alpha channel. Otherwise, + the alpha value is the NTSC greyscale + + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + equivalent of the color value, with white meaning opaque and black + transparent. In terms of the Porter-Duff compositing algebra, + <i>draw</i> replaces the <i>dst</i> pixels with (<i>src</i> in <i>mask</i>) over <i>dst</i>. (In + the extended form, “over” is replaced by <i>op</i>).<br> + + </table> + The various pixel channel formats involved need not be identical. + If the channels involved are smaller than 8-bits, they will be + promoted before the calculation by replicating the extant bits; + after the calculation, they will be truncated to their proper + sizes.<br> + + </table> + <tt><font size=+1>gendraw(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>r</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>p0</i><tt><font size=+1>,</font></tt> <i>mask</i><tt><font size=+1>,</font></tt> <i>p1</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Similar to <i>draw</i> except that <i>gendraw</i> aligns the source and mask + differently: <i>src</i> is aligned so <i>p0</i> corresponds to <i>r</i><tt><font size=+1>.min</font></tt> and <i>mask</i> + is aligned so <i>p1</i> corresponds to <i>r</i><tt><font size=+1>.min</font></tt><i>.</i> For most purposes with + simple masks and source images, <tt><font size=+1>draw</font></tt> is sufficient, but <tt><font size=+1>gendraw</font></tt> + is the general operator and the one all other + drawing primitives are built upon.<br> + + </table> + <tt><font size=+1>drawreplxy(</font></tt><i>min</i><tt><font size=+1>,</font></tt><i>max</i><tt><font size=+1>,</font></tt><i>x</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Clips <i>x</i> to be in the half-open interval [<i>min</i>, <i>max</i>) by adding or + subtracting a multiple of <i>max-min</i>.<br> + + </table> + <tt><font size=+1>drawrepl(</font></tt><i>r</i><tt><font size=+1>,</font></tt><i>p</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Clips the point <i>p</i> to be within the rectangle <i>r</i> by translating + the point horizontally by an integer multiple of rectangle width + and vertically by the height.<br> + + </table> + <tt><font size=+1>replclipr(</font></tt><i>i</i><tt><font size=+1>,</font></tt><i>repl</i><tt><font size=+1>,</font></tt><i>clipr</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Because the image data is stored on the server, local modifications + to the <tt><font size=+1>Image</font></tt> data structure itself will have no effect. <i>Repclipr</i> + modifies the local <tt><font size=+1>Image</font></tt> data structure’s <tt><font size=+1>repl</font></tt> and <tt><font size=+1>clipr</font></tt> fields, + and notifies the server of their modification.<br> + + </table> + <tt><font size=+1>line(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>p0</i><tt><font size=+1>,</font></tt> <i>p1</i><tt><font size=+1>,</font></tt> <i>end0</i><tt><font size=+1>,</font></tt> <i>end1</i><tt><font size=+1>,</font></tt> <i>thick</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Line draws in <i>dst</i> a line of width 1+2*<i>thick</i> pixels joining points + <i>p0</i> and <i>p1</i>. The line is drawn using pixels from the <i>src</i> image aligned + so <i>sp</i> in the source corresponds to <i>p0</i> in the destination. The + line touches both <i>p0</i> and <i>p1</i>, and <i>end0</i> and <i>end1</i> specify how the + ends of the line are drawn. <tt><font size=+1>Endsquare + </font></tt>terminates the line perpendicularly to the direction of the line; + a thick line with <tt><font size=+1>Endsquare</font></tt> on both ends will be a rectangle. + <tt><font size=+1>Enddisc</font></tt> terminates the line by drawing a disc of diameter 1+2*<i>thick</i> + centered on the end point. <tt><font size=+1>Endarrow</font></tt> terminates the line with an + arrowhead whose tip touches the endpoint. + The macro <tt><font size=+1>ARROW</font></tt> permits explicit control of the shape of the arrow. + If all three parameters are zero, it produces the default arrowhead, + otherwise, <i>a</i> sets the distance along line from end of the regular + line to tip, <i>b</i> sets the distance along line from the barb to the + tip, and <i>c</i> sets the distance perpendicular to the + line from edge of line to the tip of the barb, all in pixels.<br> + <i>Line</i> and the other geometrical operators are equivalent to calls + to <i>gendraw</i> using a mask produced by the geometric procedure.<br> + + </table> + <tt><font size=+1>poly(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>p</i><tt><font size=+1>,</font></tt> <i>np</i><tt><font size=+1>,</font></tt> <i>end0</i><tt><font size=+1>,</font></tt> <i>end1</i><tt><font size=+1>,</font></tt> <i>thick</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Poly</i> draws a general polygon; it is conceptually equivalent to + a series of calls to <i>line</i> joining adjacent points in the array + of <tt><font size=+1>Points</font></tt> <i>p</i>, which has <i>np</i> elements. The ends of the polygon are + specified as in <i>line</i>; interior lines are terminated with <tt><font size=+1>Enddisc</font></tt> + to make smooth joins. The source is aligned so <i>sp + </i>corresponds to <i>p</i><tt><font size=+1>[0]</font></tt>.<br> + + </table> + <tt><font size=+1>fillpoly(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>p</i><tt><font size=+1>,</font></tt> <i>np</i><tt><font size=+1>,</font></tt> <i>wind</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Fillpoly</i> is like <i>poly</i> but fills in the resulting polygon rather + than outlining it. The source is aligned so <i>sp</i> corresponds to + <i>p</i><tt><font size=+1>[0]</font></tt>. The winding rule parameter <i>wind</i> resolves ambiguities about + what to fill if the polygon is self-intersecting. If <i>wind</i> is <tt><font size=+1>~0</font></tt>, + a pixel is inside the polygon if the polygon’s winding number + about the point is non-zero. If <i>wind</i> is <tt><font size=+1>1</font></tt>, a pixel is inside if + the winding number is odd. Complementary values (0 or ~1) cause + outside pixels to be filled. The meaning of other values is undefined. + The polygon is closed with a line if necessary.<br> + + </table> + <tt><font size=+1>bezier(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>a</i><tt><font size=+1>,</font></tt> <i>b</i><tt><font size=+1>,</font></tt> <i>c</i><tt><font size=+1>,</font></tt> <i>d</i><tt><font size=+1>,</font></tt> <i>end0</i><tt><font size=+1>,</font></tt> <i>end1</i><tt><font size=+1>,</font></tt> <i>thick</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Bezier</i> draws the cubic Bezier curve defined by <tt><font size=+1>Points</font></tt> <i>a</i>, <i>b</i>, <i>c</i>, + and <i>d</i>. The end styles are determined by <i>end0</i> and <i>end1</i>; the thickness + of the curve is 1+2*<i>thick</i>. The source is aligned so <i>sp</i> in <i>src</i> + corresponds to <i>a</i> in <i>dst</i>.<br> + + </table> + <tt><font size=+1>bezspline(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>p</i><tt><font size=+1>,</font></tt> <i>end0</i><tt><font size=+1>,</font></tt> <i>end1</i><tt><font size=+1>,</font></tt> <i>thick</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Bezspline</i> takes the same arguments as <i>poly</i> but draws a quadratic + B-spline (despite its name) rather than a polygon. If the first + and last points in <i>p</i> are equal, the spline has periodic end conditions.<br> + + </table> + <tt><font size=+1>bezsplinepts(</font></tt><i>pt</i><tt><font size=+1>,</font></tt> <i>npt</i><tt><font size=+1>,</font></tt> <i>pp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Bezsplinepts</i> returns in <i>pp</i> a list of points making up the open + polygon that <i>bezspline</i> would draw. The caller is responsible for + freeing <i>*pp</i>.<br> + + </table> + <tt><font size=+1>fillbezier(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>a</i><tt><font size=+1>,</font></tt> <i>b</i><tt><font size=+1>,</font></tt> <i>c</i><tt><font size=+1>,</font></tt> <i>d</i><tt><font size=+1>,</font></tt> <i>wind</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Fillbezier</i> is to <i>bezier</i> as <i>fillpoly</i> is to <i>poly</i>.<br> + + </table> + <tt><font size=+1>fillbezspline(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>p</i><tt><font size=+1>,</font></tt> <i>wind</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Fillbezspline</i> is like <i>fillpoly</i> but fills the quadratic B-spline + rather than the polygon outlined by <i>p</i>. The spline is closed with + a line if necessary.<br> + + </table> + <tt><font size=+1>ellipse(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>c</i><tt><font size=+1>,</font></tt> <i>a</i><tt><font size=+1>,</font></tt> <i>b</i><tt><font size=+1>,</font></tt> <i>thick</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Ellipse</i> draws in <i>dst</i> an ellipse centered on <i>c</i> with horizontal + and vertical semiaxes <i>a</i> and <i>b</i>. The source is aligned so <i>sp</i> in + <i>src</i> corresponds to <i>c</i> in <i>dst</i>. The ellipse is drawn with thickness + 1+2*<i>thick</i>.<br> + + </table> + <tt><font size=+1>fillellipse(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>c</i><tt><font size=+1>,</font></tt> <i>a</i><tt><font size=+1>,</font></tt> <i>b</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Fillellipse</i> is like <i>ellipse</i> but fills the ellipse rather than + outlining it.<br> + + </table> + <tt><font size=+1>arc(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>c</i><tt><font size=+1>,</font></tt> <i>a</i><tt><font size=+1>,</font></tt> <i>b</i><tt><font size=+1>,</font></tt> <i>thick</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>,</font></tt> <i>alpha</i><tt><font size=+1>,</font></tt> <i>phi</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Arc</i> is like <i>ellipse</i>, but draws only that portion of the ellipse + starting at angle <i>alpha</i> and extending through an angle of <i>phi</i>. + The angles are measured in degrees counterclockwise from the positive + <i>x</i> axis.<br> + + </table> + <tt><font size=+1>fillarc(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>c</i><tt><font size=+1>,</font></tt> <i>a</i><tt><font size=+1>,</font></tt> <i>b</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>,</font></tt> <i>alpha</i><tt><font size=+1>,</font></tt> <i>phi</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Fillarc</i> is like <i>arc</i>, but fills the sector with the source color.<br> + + </table> + <tt><font size=+1>icossin(</font></tt><i>deg</i><tt><font size=+1>,</font></tt> <i>cosp</i><tt><font size=+1>,</font></tt> <i>sinp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Icossin</i> stores in <tt><font size=+1>*</font></tt><i>cosp</i> and <tt><font size=+1>*</font></tt><i>sinp</i> scaled integers representing + the cosine and sine of the angle <i>deg</i>, measured in integer degrees. + The values are scaled so cos(0) is 1024.<br> + + </table> + <tt><font size=+1>icossin2(</font></tt><i>x</i><tt><font size=+1>,</font></tt> <i>y</i><tt><font size=+1>,</font></tt> <i>cosp</i><tt><font size=+1>,</font></tt> <i>sinp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Icossin2</i> is analogous to <i>icossin,</i> with the angle represented not + in degrees but implicitly by the point (<i>x</i>,<i>y</i>). It is to <i>icossin</i> + what <tt><font size=+1>atan2</font></tt> is to <tt><font size=+1>atan</font></tt> (see <a href="../man3/sin.html"><i>sin</i>(3)</a>).<br> + + </table> + <tt><font size=+1>border(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>r</i><tt><font size=+1>,</font></tt> <i>i</i><tt><font size=+1>,</font></tt> <i>color</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>Border</i> draws an outline of rectangle <i>r</i> in the specified <i>color</i>. + The outline has width <i>i</i>; if positive, the border goes inside the + rectangle; negative, outside. The source is aligned so <i>sp</i> corresponds + to <i>r</i><tt><font size=+1>.min</font></tt><i>.<br> + </i> + </table> + <tt><font size=+1>string(</font></tt><i>dst</i><tt><font size=+1>,</font></tt> <i>p</i><tt><font size=+1>,</font></tt> <i>src</i><tt><font size=+1>,</font></tt> <i>sp</i><tt><font size=+1>,</font></tt> <i>font</i><tt><font size=+1>,</font></tt> <i>s</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <i>String</i> draws in <i>dst</i> characters specified by the string <i>s</i> and <i>font</i>; + it is equivalent to a series of calls to <i>gendraw</i> using source + <i>src</i> and masks determined by the character shapes. The text is + positioned with the left of the first character at <i>p</i><tt><font size=+1>.x</font></tt> and the + top of the line of text at <i>p</i><tt><font size=+1>.y</font></tt>. The source is positioned so <i>sp</i> + in + <i>src</i> corresponds to <i>p</i> in <i>dst</i>. <i>String</i> returns a <tt><font size=+1>Point</font></tt> that is the + position of the next character that would be drawn if the string + were longer.<br> + For characters with undefined or zero-width images in the font, + the character at font position 0 (NUL) is drawn.<br> + The other string routines are variants of this basic form, and + have names that encode their variant behavior. Routines whose + names contain <tt><font size=+1>rune</font></tt> accept a string of Runes rather than UTF-encoded + bytes. Routines ending in <tt><font size=+1>n</font></tt> accept an argument, <i>n</i>, that defines + the number of characters to draw rather than + accepting a NUL-terminated string. Routines containing <tt><font size=+1>bg</font></tt> draw + the background behind the characters in the specified color (<i>bg</i>) + and alignment (<i>bgp</i>); normally the text is drawn leaving the background + intact.<br> + The routine <i>_string</i> captures all this behavior into a single operator. + Whether it draws a UTF string or Rune string depends on whether + <i>s</i> or <i>r</i> is null (the string length is always determined by <i>len</i>). + If <i>bg</i> is non-null, it is used as a background color. The <i>clipr</i> + argument allows further management of clipping when + drawing the string; it is intersected with the usual clipping + rectangles to further limit the extent of the text.<br> + + </table> + <tt><font size=+1>drawsetdebug(</font></tt><i>on</i><tt><font size=+1>)<br> + </font></tt> + <table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Turns on or off debugging output (usually to a serial line) according + to whether <i>on</i> is non-zero.<br> + + </table> + +</table> +<p><font size=+1><b>SOURCE </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <tt><font size=+1>/usr/local/plan9/src/libdraw<br> + </font></tt> +</table> +<p><font size=+1><b>SEE ALSO </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + <a href="../man3/graphics.html"><i>graphics</i>(3)</a>, <a href="../man3/stringsize.html"><i>stringsize</i>(3)</a>, <a href="../man7/color.html"><i>color</i>(7)</a>, <a href="../man7/utf.html"><i>utf</i>(7)</a>, <a href="../man3/addpt.html"><i>addpt</i>(3)</a> + <table border=0 cellpadding=0 cellspacing=0><tr height=5><td></table> + + T. Porter, T. Duff. “Compositing Digital Images”, <i>Computer Graphics</i> + (Proc. SIGGRAPH), 18:3, pp. 253-259, 1984.<br> + +</table> +<p><font size=+1><b>DIAGNOSTICS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + These routines call the graphics error function on fatal errors.<br> + +</table> +<p><font size=+1><b>BUGS </b></font><br> + +<table border=0 cellpadding=0 cellspacing=0><tr height=2><td><tr><td width=20><td> + + Anti-aliased characters can be drawn by defining a font with multiple + bits per pixel, but there are no anti-aliasing geometric primitives.<br> + +</table> + +<td width=20> +<tr height=20><td> +</table> +<!-- TRAILER --> +<table border=0 cellpadding=0 cellspacing=0 width=100%> +<tr height=15><td width=10><td><td width=10> +<tr><td><td> +<center> +<a href="../../"><img src="../../dist/spaceglenda100.png" alt="Space Glenda" border=1></a> +</center> +</table> +<!-- TRAILER --> +</body></html> |