$Id: CODING_STYLE,v 1.7 2004/02/07 23:11:42 mbn Exp $

ClanLib coding style and conventions:
--------------------------------------

1. All classes have a "CL_" prefix. Eg. CL_Display, CL_SoundBuffer...
2. All macros have a "cl_" prefix. Eg. cl_assert, cl_info...

3. We do NOT use K&R style C style. We use the special ClanSoft variant of
the Microsoft style!! Please do NOT use K&R style and not GNU style either.
Braces should look like this:

int CL_MyClass::my_func(int arg1, int arg2)
{
	if (...)
	{
		switch (whatever)
		{
		case 1:
			break;
		
		case 2:
			{
				int i = 5;
				...
			}
			break;
		}
	}
	else
	{
	}
}

Please try to follow this indenting style as closely as you can. If
you are using Emacs you can set the coding style with:

(c-set-style "linux") or C-c . linux

4. We always use TABS, and NEVER SPACES to do indenting. This is because we
want people to be able to pick their own tab size. I run with 4, but others
like 8 and some like 2.

So please don't use spaces. It will have a very bad effect when someone else
uses another tab size than you. For instance, imagine the following was
written by someone using tabs, and then you add a section with spaces:
(all is written here with spaces so people will notice the difference seen
with other tab sizes than their own)

	void my_func()
	{
	    int a,b,c,d;
	    a = b + c/d;
	    
	    // added section with spaces:
	    d = a;
	    c = b/d;
	    // end of space section
	    
	    do_something(a,b,c,d);
	}

So it looks nice to you - but then we watch it with someone that has tab
size 8:

	void my_func();
	{
	        int a,b,c,d;
	        a = b + c/d;
	    
	    // added section with spaces:
	    d = a;
	    c = b/d;
	    // end of space section
	
	        do_something(a,b,c,d);
	}

Not very nice, is it?

Many unix editors use a "smart" indenting algorithm which will fuck things
even more up. They exchange spaces with tabs when reaching a given size
(normally 8 or 4), but that just isn't very smart. The result is that some
sections are spaces, and others are tabbed - all messed into one pile of
junk.

So please verify that your editor does indenting correct. This is
important.

5. Function names and variables are always in small, and underscore is used
where other people often use a captial letter.
Eg. MyVariable -> my_variable.

6. Variable access functions have a set/get prefix.
Eg. int size()         -> int get_size()
    void size(int s)   -> void set_size(int s)

7. STL and variable names.

Do NOT use the "using namespace std;" command. Not in API header or in source
files. You may be the world champion in STL, but for us other mortals its NICE
to be able to read what is STL and whats not.

Also don't use two letter variable names and avoid to do aggressive shortening
of common words (ie. cnt, num, refcnt, glph, fnt, idx). Its annoying to read
if you have to stop up and think for every variable you encounter just to try
figure out what it stands for. :) Yes we don't all speak english natively.

8. The API documentation

ClanLib uses a reference documentation system called pce2. It builds the
reference by parsing the API header files where it looks for the
documentation. There are the following types of documentation:

1) Short description.

The marker for short description is //:

The short description is used at top of the class reference pages and
function pages. Its supposed to be "a one sentence description". Example:

	//: Sprite image class.
	class CL_Sprite
	{ ...

Short descriptions do not support markup and should not include any further
markup tags (bold, italic, paragraph, etc etc).

2) Long description.

The marker for long description is //-

The long description is also known as the "Detailed description:" part of
the reference pages. This is where the class/functions purpose and
functional details are explained.

Long descriptions are supposed to put everything into html markup tags. Use
the paragraph (
Text
) tag for text. Example:

	//: Sprite image class.
	//- <p>CL_Sprite is the image class of ClanLib. A sprite is a serie
	//- of images (each called a frame) that somehow have a connection
	//- to each others. It could be all the images needed to animate a
	//- man, or it could be all the different tiles of a tile map.</p>
	class CL_Sprite
	{ ...

3) Function groups.

Functions in a class is grouped into different sections. The typical ones
are Construction, Attributes, Operations and Implementation. These groups
are marked up like this:

	//! Construction:
	//! Attributes:
	//! Operations:
	//! Implementation:

Any functions following such a group markup will belong to that group. The
group markups are placed at the beginning of the line:

	//! Construction:
	public:
		//: Constructs a sprite object.
		//- <p>Blah blah, this will make a sprite, surprise!</p>
		CL_Sprite();

4) Function parameters.

The marker for a function parameter is //param name: description

Parameters of a function are desired to have a parameter description. An example:

	//! Operations:
	public:
		//: Draws the sprite onto back buffer.
		//- <p>The draw function will draw the current frame of the
		//- sprite at the specified position, using the alignment
		//- and other attributes specified for the sprite.</p>
		//param x: x position of where to draw the sprite.
		//param y: y position of where to draw the sprite.
		//param gc: Graphic context used as target. If null, current
		//param gc: selected display window will be used.
		void draw(int x, int y, CL_GraphicContext *gc = 0);

5) See also.

The marker for adding a "See also" reference is //also: text

Example:

	//: Sprite image class.
	//- <p>CL_Sprite is the image class of ClanLib. A sprite is a serie
	//- of images (each called a frame) that somehow have a connection
	//- to each others. It could be all the images needed to animate a
	//- man, or it could be all the different tiles of a tile map.</p>
	//also: <a href="../../overview/sprite.html">Sprite overview</a>
	//also: CL_SpriteDescription
	class CL_Sprite
	{ ...

6) Polymorph functions.

If there exist several functions with the same name, then they share one
common reference page for all of them. The documentation of them should be
placed in front of the first function:

	//! Operations:
	public:
		//: Draws the sprite onto back buffer.
		//- <p>The draw function will draw the current frame of the
		//- sprite at the specified position, using the alignment
		//- and other attributes specified for the sprite.</p>
		//param x: x position of where to draw the sprite.
		//param y: y position of where to draw the sprite.
		//param dest: Destination rectangle of where to draw sprite.
		//param gc: Graphic context used as target. If null, current
		//param gc: selected display window will be used.
		void draw(int x, int y, CL_GraphicContext *gc = 0);

		void draw(CL_Rect &dest, CL_GraphicContext *gc = 0);

7) Class groups and header file info.

Each header file should contain below the GPL notice:
//! clan{group}="{section}"
{group} denotes the ClanLib group (eg Core, Display, GUI)
{section} denotes the group section (eg "Controls" for GUI)

To denote which base header file a class belongs to:
//! header={fname}.h
{fname} denotes the base header file name eg "display"



There is more things than there - but I think this summarizes the most
important issues. In general, just do like the other source files do.
