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> Plugin Writer's Guide (0.10.36)</TH
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>3.2. Using the Project Stamp</A
></H1
><P
> The first thing to do when making a new element is to specify some basic
details about it: what its name is, who wrote it, what version number it
is, etc. We also need to define an object to represent the element and to
store the data the element needs. These details are collectively known as
the <SPAN
CLASS="emphasis"
><I
CLASS="emphasis"
>boilerplate</I
></SPAN
>.
</P
><P
> The standard way of defining the boilerplate is simply to write some code,
and fill in some structures. As mentioned in the previous section, the
easiest way to do this is to copy a template and add functionality
according to your needs. To help you do so, there is a tool in the
<TT
CLASS="filename"
>./gst-plugins/tools/</TT
> directory.
This tool, <TT
CLASS="filename"
>make_element</TT
>, is a command line utility
that creates the boilerplate code for you.
</P
><P
> To use <B
CLASS="command"
>make_element</B
>, first open up a terminal window.
Change to the <TT
CLASS="filename"
>gst-template/gst-plugin/src</TT
>
directory, and then run the <B
CLASS="command"
>make_element</B
> command. The
arguments to the <B
CLASS="command"
>make_element</B
> are:
</P
><P
></P
><OL
TYPE="1"
><LI
><P
>the name of the plugin, and</P
></LI
><LI
><P
> the source file that the tool will use. By default,
<TT
CLASS="filename"
>gstplugin</TT
> is used.
</P
></LI
></OL
><P
> For example, the following commands create the MyFilter plugin based on
the plugin template and put the output files in the
<TT
CLASS="filename"
>gst-template/gst-plugin/src</TT
>
directory:
</P
><PRE
CLASS="screen"
> <SAMP
CLASS="prompt"
>shell $ </SAMP
><KBD
CLASS="userinput"
>cd gst-template/gst-plugin/src</KBD
>
<SAMP
CLASS="prompt"
>shell $ </SAMP
><KBD
CLASS="userinput"
>../tools/make_element MyFilter</KBD
>
</PRE
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> Capitalization is important for the name of the plugin. Keep in mind
that under some operating systems, capitalization is also important
when specifying directory and file names in general.
</P
></TD
></TR
></TABLE
></DIV
><P
> The last command creates two files:
<TT
CLASS="filename"
>gstexamplefilter.c</TT
> and
<TT
CLASS="filename"
>gstexamplefilter.h</TT
>.
</P
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> It is recommended that you create a copy of the <TT
CLASS="filename"
>gst-plugin</TT
>
directory before continuing.
</P
></TD
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><P
> Now one needs to adjust the <TT
CLASS="filename"
>Makefile.am</TT
> to use the
new filenames and run <TT
CLASS="filename"
>autogen.sh</TT
> from the parent
directory to bootstrap the build environment. After that, the project
can be built and installed using the well known
<KBD
CLASS="userinput"
>make && sudo make install</KBD
> commands.
</P
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> Be aware that by default <TT
CLASS="filename"
>autogen.sh</TT
> and
<TT
CLASS="filename"
>configure</TT
> would choose <TT
CLASS="filename"
>/usr/local</TT
>
as a default location. One would need to add
<TT
CLASS="filename"
>/usr/local/lib/gstreamer-0.10</TT
>
to <CODE
CLASS="symbol"
>GST_PLUGIN_PATH</CODE
> in order to make the new plugin
show up in gstreamer.
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