interface canvas : widget {\c{\fbox{canvas}}
canvas(char *p, char* options=""); canvas(widget* w, char *p, char* options=""); void tag(int id, char* tag); char* tags(int id); void move(int id, int x, int y); void move(char* id, int x, int y); item bitmap(int x1, int y1, char* bm, char* opts=""); item line(int x1, int y1, int x2, int y2, char* opts =""); item line(char* linespec, char* opts =""); item circle(int x1, int y1, int rad, char* opts =""); item oval(int x1, int y1, int x2, int y2, char* opts =""); item polygon(char* linespec, char* opts =""); item rectangle(int x1,int y1,int ,int ,char* opts =""); item text(int x1, int y1, char* txt, char* opts=""); item window(int x1, int y1, char* w, char* opts=""); item current(); item overlapping(int x, int y); itemconfigure(int it, char* options); itemconfigure(char* tag, char* options); itembind(int it, char* s, action&, char* args = "" ); itembind(char* tg,char* s,action&, char* args = "" ); void postscript(char* file, char* options=""); };
Currently, the graphic items bitmap, line, oval, polygon and rectangle may be created and, in addition, text items and window items consisting of a widget. The function overlapping may be used to retrieve the item overlapping a particular position.
In addition, the canvas class has auxiliary functions which are needed to support the functionality provided by the item class. The canvas may be written as Postscript to a file with the function .