These are the coding standards I am using. If you make some changes to the
code, please attempt to follow these rules.

Gershon Elber

gershon@cs.technion.ac.il

Compile with IRIT makefile/flag tools to ensure maximum warnings. Attempt
to minimize the number of warnings.
------------------------------------------------------------------------------


GENERAL
-------

Code should not exceed column 80. If the code is going to "look"
better with more that 80 columns it is allowed but should be
restricted as possible.

NESTING
-------

Nesting of all expressions is by 4 spaces. Tabs used are 8 spaces.

SPACES
------

No spaces are allowed after '(' and before ')' in a function call or
math expression. However, spaces are allowed between arguments after
the comma or between operations:

	sin(x);
	Function1(x, y, z);
	x + 5 * sin(y);

Spaces should also be placed between operators.  That is "p -> Pt[1] == y"
(and not ("p->Pt[1]==y")).

FUNCTION HEADER'S COMMENT
-------------------------

The comment of a function (method in C++) will consist of the following
sections:

* DESCRIPTION: a general descript of the function.  This block of information
  will be copied to the programmer manual.  Two types of records can appear
  in this section:

  1. A line terminated with 'M' - this line will be copied and be formated.
  2. A line terminated with 'V' - this line will be copied verbatim as is.

* PARAMETERS: enumeration of all function's parameter one per line and the
  description of the parameter.  Several parameters of very close association
  may be placed in one line (for example "U, V: the parametic location on S").
  If the function gets no parameters, "None" should appear.

* RETURN VALUE: the type of the returned value, (or void if no return value)
  and a description as to its meaning.

* SEE ALSO: list of other functions that are related.
  This section is optional and is unlikely to exist in local static functions.

* KEYWORDS: list of keywords that are related, with the function name as the
  first keyword.  This section does not exist in local static functions.

Example:

/*****************************************************************************
* DESCRIPTION:								     M
* Multi line description of the function. This is a text that will be copied M
* to the programmer's manual iff the end of the line is M instead of a *     M
* like this line.							     M
*   If a V is found at the end of the line, it is copied Verbatim. Example:  M
* A x + B y + C z + D w + E = 0						     V
* defines an hyper plane in four space.        				     M
*									     M
*   Proper indentation will be given to algorithms or sequences that begin   M
* with an alpha-numeric values followed by a point. For example:             M
*									     M
* 1. One letter	which sets the option letter (i.e. 'x' for option '-x').     M
*    1.1 Allow even sub sequences.					     M
* 2. '!' or '%'	to determines if this option is	really optional	('%') or     M
*    it	must be provided by the user ('!').				     M
* 3. '-' always.							     M
* 4. Sequences that start with either '!' or '%'.			     M
*       Each sequence will be followed by one or two characters	which        M
*    defines the kind of the input:			   		     M
*    4.1 d, x, o, u - integer is expected (decimal, hex, octal base or	     M
*		  unsigned).						     M
*    4.2 D, X, O, U - long integer is expected (same as above).		     M
*    4.3 f - float number is expected.					     M
*									     *
* PARAMETERS:								     M
*   I1: one per line, must have an M at the end to show up in prog manual.   M
*   C2: this parameter is the second one.				     M
*									     *
* RETURN VALUE:								     M
*   int: Number of manuals to create.					     M
*									     *
* SEE ALSO:     (only if a global non static function)                       M
*   ProgrammerManual2, ReferenceManual					     M
*                                                                            *
* KEYWORDS:	(only if a global non static function).			     M
*	ProgrammerManual, manual, documentation				     M
*****************************************************************************/
int ProgrammerManual(int I1, char C2)
{
}

Functions that are obviously auxiliary can have the postfix Aux, must be
static, and can have documentation as:

/*****************************************************************************
* AUXILIARY:								     *
* Auxiliary function to function SymbPiecewiseRuledSrfApprox		     *
*****************************************************************************/
static CagdSrfStruct *CagdPiecewiseRuledSrfAux(CagdSrfStruct *Srf,
					       CagdBType ConsistentDir,
					       CagdRType Epsilon,
					       CagdSrfDirType Dir)

The function comment must be followed very precisely so they could be
grabbed out of the code directly into the programmer's manual. If you
are using the emacs editor (If you dont, you better switch to it), add
irit.el from the irit subdirectory to your .emacs. This emacs-lisp file
contains a definition for make-irit-c-function which expands a skeleton
from a given prototype. Once irit.el is installed, type
'M-x make-irit-c-function' followed by a function prototype 'int Test(char c)'.

Static functions will never have 'M' or 'V' as last character in line. Only
'*'. The 'SEE ALSO' section is recommended but optional.

C++ code should use the "Class::Method" as the function name in the
keyword and the "SEE ALSO" section would include the "Class" name.

INTERNAL COMMENTS
-----------------

Internal comments will be aligned to the right to column 80 if the
are commenting expression in the same line:

	i %= 2;						      /* Is i even? */

Comments that explains the following block, will be left aligned as
the block. The comment does not need to be right aligned to column 80
as well:

	/* This is a comment for the next line. */
	i %= 2;

All comments should be properly Capitalized and terminate with a point.
C++ code should not use the // comment notation.


FUNCTION AND VARIABLE NAMES
---------------------------

Both function and variable names will have NO UNDERSCORES. Words will be
capitalized to distinguish them from each other. Variables of single
character will be lower case. Examples of valid names:

    ThisIsAFunction, VariableOne, X1, i, j

Global functions should prevent from name space collisions, via the use
of related and unique prefixes.  For example the "Cagd" prefix in the
function (and variables names) of the cagd library.

If a function (or a variable) is to be used in a library by more than one
module, yet the function (or a variable) is not to be considered global, the
function (or variable) must be prefixed with underscore ('_').  For example,
"_CagdMakePolygon" or "_CagdSrf2PolygonStrips".

CLASSES, STRUCTURES and UNIONS
------------------------------

Structures must be typedef defined.  A structure will be defined with
indentation of four spaces.  If next and prev slots are allocated, they
must be called Pnext and Pprev respectively. If an attribute slot
(IPAttributeStruct) is also used, it must be called Attr:

typedef struct CagdPtStruct {
    struct CagdPtStruct *Pnext;
    struct IPAttributeStruct *Attr;
    CagdPType Pt;
} CagdPtStruct;

Classes will follow the same guideline, with the methods of the class
indented four spaces as well.  The "private:" and "public:" modifiers
will be indented two spaces only.

Defined types (via typedef) will hint on themselves.  All typedef will
the the following suffixes:

* For a typedef of a structure, name of typedef will terminate with "Struct".
  For example, "IPAttributeStruct" or "CagdCrvStruct".

* For a typedef of a class, name of typedef will terminate with "Class".
  For example, "IRWindowClass" or "CagdFreeformClass".

* For a typedef of a pointer to a function, name of typedef will terminate
  with "FuncType".  For example, "CagdCompFuncType" or "IritPrsrPrintFuncType".

* All other typedefs will terminate with "Type".  For example
  "CagdRType" or "PointType".


VARIABLE'S DECLARATIONS
-----------------------

Variables will be declared at the deepest nesting possible. That is, if
a variable is used in one module, it will be local to the module. If the
variable is used in one function, it will be defined in one function. If
a variable is used in one block in one function, it will be defined in that
block.

Variables will be declared static first, followed by automatic.
Variables will be declared from simple type to complex/composed ones.
Variables that are intialized are to be declared one per line,
indented once from the indentation level of the variable
type.

While C++ allows declaration of variables everywhere, declare your variables
at the begining of the block only.  This simplifies finding declared variables.

Example:

    STATIC_DATA int
	LastCount = 0;
    STATIC_DATA RealType
	LastValue = 0.0;
    STATIC_DATA IPObjectStruct *TmpObj;
    char Str[LINE_LEN], *p,
	*Name = "MyName";
    int Dir = REAL_PTR_TO_INT(RDir),
	OldOrder = Dir == CAGD_CONST_U_DIR ? Srf -> VOrder : Srf -> UOrder,
	NewOrder = REAL_PTR_TO_INT(RNewOrder);
    IPObjectStruct *SrfObj;
    CagdSrfStruct *TSrf,
	*Srf = PObjSrf -> U.Srfs;

The STATIC_DATA is typically #defined to 'static' but use it and not
just 'static'. Do not use the register modifier.

Global variabel should prevent from name space collisions, via the use
of related and unique prefixes.  For example the "Cagd" prefix in the
variables (and function names) of the cagd library.  All global variables
should also be prefixed with GLOBAL_DATA.  I.e.:

    GLOBAL_DATA jmp_buf GlblLongJumpBuffer;


INPUT AND OUTPUT
----------------

Refrain from using iosteam, in C++, and use the C style printf/scanf
code.  This will reduce the size of the generated executables and will
also make all printing in the system more consistent.


PARAMETERS OF FUNCTIONS
-----------------------

Parameters of function prototypes will either be all in one line:

    int Func1Test(int Len, RealType *Vect)

or all arguments must be aligned one below the other:

    static CagdSrfStruct *CagdPiecewiseRuledSrfAux(CagdSrfStruct *Srf,
					           CagdBType ConsistentDir,
					           CagdRType Epsilon,
					           CagdSrfDirType Dir)

Local (to a file) functions must be declared static and a prototype of the
function should also be placed in the beginning of the file.  Otherwise,
for a non static function, a prototype must be place in the appropriate
header ('.h' file) file.


MACROS
------

All the names of the macros will be in uppercase and words seperated
by underscore:

#define LINE_LEN_VLONG	1024	/* Lines read from stdin/files... */
#define MIN(x, y)		((x) > (y) ? (y) : (x))

All macros that are local to a file will be defined at the beginning of
the file after the #include statements.   Global macros will be defined
in the appropriate header file.  Global macros should prevent from
name space collision, much like global variables, via the use of related
prefixes.  For example CAGD prefix in the cagd library.

Variables declared in macros will always be prefixed with underscore ('_').

POINTERS and SLOTS
------------------
Points should be seperated before and after with a space:

    X = P -> Coords[1];

This is not the case for slots of a structure:

    X = P.Coords[1];


BLOCKS
------

Blocks starts with '{' and ends with '}'. If the block is beginning of
function then it will start with '{' at column 1 and end at column 1
with '}'.  Otherwise, it will start with some expression as for/if/while
etc. in the nesting form: 

    expression {
	.
	.
	.
    }

FOR
---
	for (x = 0; x < 10; x++)

    or

	for (x = 0, i = 1;
	     x < 5;
	     x++, i--)

	The body of the for loop can never be in the same line where the ')'
    is. The ')' will be followed by '{' and the body will start in the next
    line nested 4 space deapper:

	for (....)
	    x = sin(j);
    or
	for (....) {
	    x = y / j;
	    y = j + 2;
	}

    Notice that after a semicolon (';') there must be a space or a newline.

WHILE
-----
	while (x > 0)
	    x--;				       /* Better use x = 0! */

or

	while (x > 0 && y > 0) {
	    x -= 4;
	    y -= 4;
	}

or

	while (x > 0 &&
	       x < 5)
	    x /= 2;


IF
--

	if (x > 0)
	    x = -x;

or

	if (x > 0 && y > 0) {
	    x = -x;
	    y = -y;
	}

or

	if (x > 0)
	    x = -x;
	else
	    x /= 2;

or

	if (x > 0)
	    x = -x;
	else if (x < -100)
	    x /= 20;
	else
	    x /= 2;

If an if expression has an else clause both bodies will be aligned 4
space deep (The body of the if clause can not be in same line as the
if and must be aligned with the else body).


SWITCH
------

	switch (i) {
	    case 1:
		printf("1");
		break;
	    case 2:
		printf("2");
		break;
	    case 3:
		printf("3");
		break;
	    default:
		printf("Too big");
		break;
	}


GENERAL PROGRAMMING COMMENTS
----------------------------

For portability, you should use IritMalloc, IritRealloc and IritFree
for dynamic memory maintenance. For this same reason you should also
use IritRandom/IritRandomInit and IritSleep, IritCPUTime and
IritRealTimeDate, whenever appropriate.  Employ the macros defined in
irit_sm.h as much as possible.


FINAL REMARK
------------

If you are still not sure how the code should be formated in some
specific case, consult the code. Out of 200k of lines of code, you are
most likely to find a similar case to yours.

Write your code as if it is going to become a library. Isolate and
encapsulate everything as much as possible. For modules that performs
a specific task, isolate the access to a small set of accessor
functions that have unique names using a prefix that hints on the
functionality of the module. If you must have macros and/or global
variables that are accessible to the world, make them uniquely
prefixed in a similar manner.
