--- ray/src/rt/driver.h	1989/02/02 10:41:13	1.1
+++ ray/src/rt/driver.h	1990/01/08 13:37:49	1.4
@@ -15,6 +15,7 @@ struct driver {				/* driver functions */
 	int  (*getcur)();			/* get cursor position */
 	int  (*comout)();			/* command line output */
 	int  (*comin)();			/* command line input */
+	double  pixaspect;			/* pixel aspect ratio */
 	int  xsiz, ysiz;			/* device size */
 	int  inpready;				/* input ready on device */
 };
@@ -23,6 +24,9 @@ extern int  stderr_v();			/* error vectors */
 extern int  (*wrnvec)(), (*errvec)(), (*cmdvec)();
 
 extern struct driver  *comm_init();	/* stream interface */
+					/* magic numbers for verification */
+#define COM_SENDM		0x6f37
+#define COM_RECVM		0x51da
 					/* stream commands */
 #define COM_CLEAR		0
 #define COM_PAINTR		1
@@ -31,41 +35,39 @@ extern struct driver  *comm_init();	/* stream interfac
 #define COM_COMIN		4
 #define NREQUESTS		5	/* number of valid requests */
 
-struct device {				/* interactive device */
+extern struct device {			/* interactive device */
 	char  *name;				/* device name */
 	char  *descrip;				/* description */
 	struct driver  *(*init)();		/* initialize device */
-};
+}  devtable[];				/* supported devices */
 
-extern struct device  devtable[];	/* supported devices */
-
 #define  MB1		('\n')		/* mouse button 1 */
 #define  MB2		('\r')		/* mouse button 2 */
 #define  MB3		(' ')		/* mouse button 3 */
 #define  ABORT		('C'-'@')	/* abort key */
 
-#define  MAXRES		4000		/* preposterous display resolution */
-
 /*
  *  struct driver *
- *  dname_init(name)
- *  char  *name;
+ *  dname_init(name, id)
+ *  char  *name, *id;
  *  {
  *	Initialize device and return pointer to driver
  *	functions.  Returns NULL if an error occurred.
- *	The name string is used to identify the client.
+ *	The name string identifies the driver,
+ *	and the id string identifies the client.
  *	A device can be open by at most one client.
  *	Be verbose in error reports; call stderr_v().
- *	If device has its own error output, set errvec.
+ *	If device has its own error output, set errvec,
+ *	cmdvec and wrnvec.
  *  }
  *  (*dev->close)()
  *  {
- *	Close the device.  Reset errvec to stderr_v.
+ *	Close the device.  Reset error vectors.
  *  }
  *  (*dev->clear)(xres, yres)
  *  int  xres, yres;
  *  {
- *	Clear the device for xres by yres output.  This call must
+ *	Clear the device for xres by yres output.  This call will
  *	be made prior to any output.
  *  }
  *  (*dev->paintr)(col, xmin, ymin, xmax, ymax)
@@ -96,13 +98,14 @@ extern struct device  devtable[];	/* supported devices
  *	Read an edited input string from the command line.  If
  *	an unrecognized control character is entered, terminate
  *	input and return the string with only that character.
- *	The input string should not contain a newline ('\n').
+ *	The input string should not contain a newline.
  *	Must work in consort with comout.
  *  }
  *  xsiz, ysiz
  *	The maximum allowable x and y dimensions.  If any
  *	size is allowable, these should be set to MAXRES.
  *  inpready
- *	This variable should be positive
- *	when characters are ready on the input.
+ *	This variable should be made positive asynchronously
+ *	when characters are ready on the input.  (Often easiest
+ *	to check for input during calls to paintr.)
  */