# Development Notes

## Adding Extentions

To add a new GL extension to Mesa you have to do at least the following.

- If glext.h doesn't define the extension, edit include/GL/gl.h and add code like this:

           #ifndef GL_EXT_the_extension_name
           #define GL_EXT_the_extension_name 1
           /* declare the new enum tokens */
           /* prototype the new functions */
           /* TYPEDEFS for the new functions */
           #endif

- In the src/mesa/glapi/ directory, add the new extension functions and enums to the gl_API.xml file. Then, a bunch of source files must be regenerated by executing the corresponding Python scripts.
- Find an existing extension that's similar to the new one and search the sources for code related to that extension. Implement new code as needed. In general, new state variables will be added to mtypes.h. If the extension is rather large, try to implement it in a new source file.
- If hew extension adds new GL state, the functions in get.c, enable.c and attrib.c will most likely require new code.

## Coding Style

Mesa's code style has changed over the years. Here's the latest.

Comment your code! It's extremely important that open-source code be well documented. Also, strive to write clean, easily understandable code.

3-space indentation

If you use tabs, set them to 8 columns

Brace example:

    	if (condition) {
    	   foo;
    	}
    	else {
    	   bar;
    	}

Here's the GNU indent command which will best approximate my preferred style:

    	indent -br -i3 -npcs infile.c -o outfile.c

Local variable name example: localVarName (no underscores)

Constants and macros are ALL_UPPERCASE, with _ between words

Global vars not allowed.

Function name examples:

    	glFooBar()       - a public GL entry point (in dispatch.c)
    	_mesa_FooBar()   - the internal immediate mode function
    	save_FooBar()    - retained mode (display list) function in dlist.c
    	foo_bar()        - a static (private) function
    	_mesa_foo_bar()  - an internal non-static Mesa function

## Writing a Device Driver

XXX to do

## Making a New Mesa Release

These are the instructions for making a new Mesa release.

Prerequisites (later versions may work):

- autoconf 2.50
- automake 1.4-p2
- libtool 1.4

Be sure to do a "cvs update -d ." in the Mesa directory to get all the latest files.

Update the version definitions in src/version.h

Create/edit the docs/RELNOTES-X.Y file to document what's new in the release. Edit the docs/VERSIONS file too.

Edit Make-config and change the MESA_MAJOR and/or MESA_MINOR versions.

Edit the GNU configure stuff to change versions numbers as needed: Update the version string (second argument) in the line "AM_INIT_AUTOMAKE(Mesa, 3.3)" in the configure.in file.

Remove the leading `dnl' from the line "dnl AM_MAINTAINER_MODE".

Verify the version numbers near the top of configure.in

Run "fixam -f" to disable automatic dependency tracking.

Run the bootstrap script to generate the configure script.

Edit Makefile.X11 and verify DIRECTORY is set correctly. The Mesa sources must be in that directory (or there must be a symbolic link).

Edit Makefile.X11 and verify that LIB_NAME and DEMO_NAME are correct. If it's a beta release, be sure the bump up the beta release number.

cp Makefile.X11 to Makefile so that the old-style Mesa makefiles still work. ./configure will overwrite it if that's what the user runs.

Make a symbolic link from $(DIRECTORY) to Mesa. For example, ln -s Mesa Mesa-3.3 This is needed in order to make a correct tar file in the next step.

Make the distribution files. From inside the Mesa directory:

    	make -f Makefile.X11 lib_tar
    	make -f Makefile.X11 demo_tar
    	make -f Makefile.X11 lib_zip
    	make -f Makefile.X11 demo_zip

Copy the distribution files to a temporary directory, unpack them, compile everything, and run some demos to be sure everything works.

Upload the *.tar.gz and *.zip files to ftp.mesa3d.org

Update the web site.

Make an announcement on the mailing lists: mesa3d-dev@lists.sf.net, mesa3d-users@lists.sf.net and mesa3d-announce@lists.sf.net

## Autoconf info

In order to run the bootstrap script you'll need:

    autoconf 2.50
    automake 1.4-p5
    libtool 1.4