## gimp

gimp — Main functions needed for building a GIMP plug-in. This header includes all other GIMP Library headers.

## Synopsis

    gchar*              gimp_version                        (void);
    gint                gimp_getpid                         (void);
    #define             gimp_get_data
    #define             gimp_get_data_size
    #define             gimp_set_data
    void                (*GimpInitProc)                     (void);
    void                (*GimpQuitProc)                     (void);
    void                (*GimpQueryProc)                    (void);
    void                (*GimpRunProc)                      (const gchar *name,
                                                             gint n_params,
                                                             const GimpParam *param,
                                                             gint *n_return_vals,
                                                             GimpParam **return_vals);
                        GimpPlugInInfo;
                        GimpParamDef;
                        GimpParamRegion;
    union               GimpParamData;
                        GimpParam;
    #define             MAIN
    gint                gimp_main                           (const GimpPlugInInfo *info,
                                                             gint argc,
                                                             gchar *argv[]);
    void                gimp_quit                           (void);
    void                gimp_install_procedure              (const gchar *name,
                                                             const gchar *blurb,
                                                             const gchar *help,
                                                             const gchar *author,
                                                             const gchar *copyright,
                                                             const gchar *date,
                                                             const gchar *menu_label,
                                                             const gchar *image_types,
                                                             GimpPDBProcType type,
                                                             gint n_params,
                                                             gint n_return_vals,
                                                             const GimpParamDef *params,
                                                             const GimpParamDef *return_vals);
    void                gimp_install_temp_proc              (const gchar *name,
                                                             const gchar *blurb,
                                                             const gchar *help,
                                                             const gchar *author,
                                                             const gchar *copyright,
                                                             const gchar *date,
                                                             const gchar *menu_label,
                                                             const gchar *image_types,
                                                             GimpPDBProcType type,
                                                             gint n_params,
                                                             gint n_return_vals,
                                                             const GimpParamDef *params,
                                                             const GimpParamDef *return_vals,
                                                             GimpRunProc run_proc);
    void                gimp_uninstall_temp_proc            (const gchar *name);
    GimpParam *         gimp_run_procedure                  (const gchar *name,
                                                             gint *n_return_vals,
                                                             ...);
    GimpParam *         gimp_run_procedure2                 (const gchar *name,
                                                             gint *n_return_vals,
                                                             gint n_params,
                                                             const GimpParam *params);
    void                gimp_destroy_params                 (GimpParam *params,
                                                             gint n_params);
    void                gimp_destroy_paramdefs              (GimpParamDef *paramdefs,
                                                             gint n_params);
    const gchar *       gimp_get_pdb_error                  (void);
    guint               gimp_tile_width                     (void);
    guint               gimp_tile_height                    (void);
    gint                gimp_shm_ID                         (void);
    guchar *            gimp_shm_addr                       (void);
    gdouble             gimp_gamma                          (void);
    gboolean            gimp_install_cmap                   (void);
    gint                gimp_min_colors                     (void);
    gboolean            gimp_show_tool_tips                 (void);
    gboolean            gimp_show_help_button               (void);
    GimpCheckSize       gimp_check_size                     (void);
    GimpCheckType       gimp_check_type                     (void);
    gint32              gimp_default_display                (void);
    const gchar *       gimp_wm_class                       (void);
    const gchar *       gimp_display_name                   (void);
    gint                gimp_monitor_number                 (void);
    guint32             gimp_user_time                      (void);
    const gchar *       gimp_get_progname                   (void);
    void                gimp_extension_enable               (void);
    void                gimp_extension_ack                  (void);
    void                gimp_extension_process              (guint timeout);
    GimpParasite*       gimp_parasite_find                  (const gchar *name);
    gboolean            gimp_parasite_list                  (gint *num_parasites,
                                                             gchar ***parasites);
    gboolean            gimp_parasite_attach                (const GimpParasite *parasite);
    gboolean            gimp_parasite_detach                (const gchar *name);
    gboolean            gimp_attach_new_parasite            (const gchar *name,
                                                             gint flags,
                                                             gint size,
                                                             gconstpointer data);

## Description

Main functions needed for building a GIMP plug-in. This header includes all other GIMP Library headers.

## Details

### gimp_version ()

    gchar*              gimp_version                        (void);

Returns the host GIMP version.

This procedure returns the version number of the currently running GIMP.

Returns : | GIMP version number.

### gimp_getpid ()

    gint                gimp_getpid                         (void);

Returns the PID of the host GIMP process.

This procedure returns the process ID of the currently running GIMP.

Returns : | The PID.

Since GIMP 2.4

### gimp_get_data

    #define gimp_get_data         gimp_procedural_db_get_data

### gimp_get_data_size

    #define gimp_get_data_size    gimp_procedural_db_get_data_size

Returns : |

### gimp_set_data

    #define gimp_set_data         gimp_procedural_db_set_data

### GimpInitProc ()

    void                (*GimpInitProc)                     (void);

### GimpQuitProc ()

    void                (*GimpQuitProc)                     (void);

### GimpQueryProc ()

    void                (*GimpQueryProc)                    (void);

### GimpRunProc ()

    void                (*GimpRunProc)                      (const gchar *name,
                                                             gint n_params,
                                                             const GimpParam *param,
                                                             gint *n_return_vals,
                                                             GimpParam **return_vals);

`name` : |
`n_params` : |
`param` : |
`n_return_vals` : |
`return_vals` : |

### GimpPlugInInfo

    typedef struct {
      /* called when the gimp application initially starts up */
      GimpInitProc  init_proc;

      /* called when the gimp application exits */
      GimpQuitProc  quit_proc;

      /* called by gimp so that the plug-in can inform the
       *  gimp of what it does. (ie. installing a procedure database
       *  procedure).
       */
      GimpQueryProc query_proc;

      /* called to run a procedure the plug-in installed in the
       *  procedure database.
       */
      GimpRunProc   run_proc;
    } GimpPlugInInfo;

### GimpParamDef

    typedef struct {
      GimpPDBArgType  type;
      gchar          *name;
      gchar          *description;
    } GimpParamDef;

### GimpParamRegion

    typedef struct {
      gint32 x;
      gint32 y;
      gint32 width;
      gint32 height;
    } GimpParamRegion;

### union GimpParamData

    union _GimpParamData
    {
      gint32            d_int32;
      gint16            d_int16;
      guint8            d_int8;
      gdouble           d_float;
      gchar            *d_string;
      gint32           *d_int32array;
      gint16           *d_int16array;
      guint8           *d_int8array;
      gdouble          *d_floatarray;
      gchar           **d_stringarray;
      GimpRGB          *d_colorarray;
      GimpRGB           d_color;
      GimpParamRegion   d_region;
      gint32            d_display;
      gint32            d_image;
      gint32            d_layer;
      gint32            d_layer_mask;
      gint32            d_channel;
      gint32            d_drawable;
      gint32            d_selection;
      gint32            d_boundary;
      gint32            d_path; /* deprecated */
      gint32            d_vectors;
      gint32            d_unit;
      GimpParasite      d_parasite;
      gint32            d_tattoo;
      GimpPDBStatusType d_status;
    };

### GimpParam

    typedef struct {
      GimpPDBArgType type;
      GimpParamData  data;
    } GimpParam;

### MAIN

    #define             MAIN()

### gimp_main ()

    gint                gimp_main                           (const GimpPlugInInfo *info,
                                                             gint argc,
                                                             gchar *argv[]);

The main procedure that must be called with the PLUG_IN_INFO structure and the 'argc' and 'argv' that are passed to "main".

`info` : | the PLUG_IN_INFO structure
`argc` : | the number of arguments
`argv` : | the arguments
Returns : |

### gimp_quit ()

    void                gimp_quit                           (void);

Forcefully causes the GIMP library to exit and close down its connection to main gimp application. This function never returns.

### gimp_install_procedure ()

    void                gimp_install_procedure              (const gchar *name,
                                                             const gchar *blurb,
                                                             const gchar *help,
                                                             const gchar *author,
                                                             const gchar *copyright,
                                                             const gchar *date,
                                                             const gchar *menu_label,
                                                             const gchar *image_types,
                                                             GimpPDBProcType type,
                                                             gint n_params,
                                                             gint n_return_vals,
                                                             const GimpParamDef *params,
                                                             const GimpParamDef *return_vals);

Installs a new procedure with the PDB (procedural database).

Call this function from within your plug-in's `query()` function for each procedure your plug-in implements.

The `name` parameter is mandatory and should be unique, or it will overwrite an already existing procedure (overwrite procedures only if you know what you're doing).

The `blurb`, `help`, `author`, `copyright` and `date` parameters are optional but then you shouldn't write procedures without proper documentation, should you.

`menu_label` defines the label that should be used for the procedure's menu entry. The position where to register in the menu hierarchy is chosen using `gimp_plugin_menu_register()`. This function also still accepts the old (pre-2.2) way of registering a menu entry and takes a string in the form "<Domain>/Path/To/My/Menu" (e.g. "<Image>/Filters/Render/Useless").

It is possible to register a procedure only for keyboard-shortcut activation by passing a `menu_label` to `gimp_install_procedure()` but not registering any menu path with `gimp_plugin_menu_register()`. In this case, the given `menu_label` will only be used as the procedure's user-visible name in the keyboard shortcut editor.

`image_types` is a comma separated list of image types, or actually drawable types, that this procedure can deal with. Wildcards are possible here, so you could say "RGB*" instead of "RGB, RGBA" or "*" for all image types. If the procedure doesn't need an image to run, use the empty string.

`type` must be one of GIMP_PLUGIN or GIMP_EXTENSION. Note that temporary procedures must be installed using `gimp_install_temp_proc()`.

NOTE: Unlike the GIMP 1.2 API, GIMP_EXTENSION no longer means that the procedure's menu prefix is <Toolbox>, but that it will install temporary procedures. Therefore, the GIMP core will wait until the GIMP_EXTENSION procedure has called `gimp_extension_ack()`, which means that the procedure has done its initialization, installed its temporary procedures and is ready to run.

Not calling `gimp_extension_ack()` from a GIMP_EXTENSION procedure will cause the GIMP core to lock up.

Additionally, a GIMP_EXTENSION procedure with no parameters (`n_params` == 0 and `params` == NULL) is an "automatic" extension that will be automatically started on each GIMP startup.

`name` : | the procedure's name.
`blurb` : | a short text describing what the procedure does.
`help` : | the help text for the procedure (usually considerably longer than `blurb`).
`author` : | the procedure's author(s).
`copyright` : | the procedure's copyright.
`date` : | the date the procedure was added.
`menu_label` : | the label to use for the procedure's menu entry, or NULL if the procedure has no menu entry.
`image_types` : | the drawable types the procedure can handle.
`type` : | the type of the procedure.
`n_params` : | the number of parameters the procedure takes.
`n_return_vals` : | the number of return values the procedure returns.
`params` : | the procedure's parameters.
`return_vals` : | the procedure's return values.

### gimp_install_temp_proc ()

    void                gimp_install_temp_proc              (const gchar *name,
                                                             const gchar *blurb,
                                                             const gchar *help,
                                                             const gchar *author,
                                                             const gchar *copyright,
                                                             const gchar *date,
                                                             const gchar *menu_label,
                                                             const gchar *image_types,
                                                             GimpPDBProcType type,
                                                             gint n_params,
                                                             gint n_return_vals,
                                                             const GimpParamDef *params,
                                                             const GimpParamDef *return_vals,
                                                             GimpRunProc run_proc);

Installs a new temporary procedure with the PDB (procedural database).

A temporary procedure is a procedure which is only available while one of your plug-in's "real" procedures is running.

See `gimp_install_procedure()` for most details.

`type` must be GIMP_TEMPORARY or the function will fail.

`run_proc` is the function which will be called to execute the procedure.

NOTE: Normally, plug-in communication is triggered by the plug-in and the GIMP core only responds to the plug-in's requests. You must explicitly enable receiving of temporary procedure run requests using either `gimp_extension_enable()` or `gimp_extension_process()`. See this functions' documentation for details.

`name` : | the procedure's name.
`blurb` : | a short text describing what the procedure does.
`help` : | the help text for the procedure (usually considerably longer than `blurb`).
`author` : | the procedure's author(s).
`copyright` : | the procedure's copyright.
`date` : | the date the procedure was added.
`menu_label` : | the procedure's menu label, or NULL if the procedure has no menu entry.
`image_types` : | the drawable types the procedure can handle.
`type` : | the type of the procedure.
`n_params` : | the number of parameters the procedure takes.
`n_return_vals` : | the number of return values the procedure returns.
`params` : | the procedure's parameters.
`return_vals` : | the procedure's return values.
`run_proc` : | the function to call for executing the procedure.

### gimp_uninstall_temp_proc ()

    void                gimp_uninstall_temp_proc            (const gchar *name);

Uninstalls a temporary procedure which has previously been installed using `gimp_install_temp_proc()`.

`name` : | the procedure's name

### gimp_run_procedure ()

    GimpParam *         gimp_run_procedure                  (const gchar *name,
                                                             gint *n_return_vals,
                                                             ...);

This function calls a GIMP procedure and returns its return values.

The procedure's parameters are given by a va_list in the format (type, value, type, value) and must be terminated by GIMP_PDB_END.

This function converts the va_list of parameters into an array and passes them to `gimp_run_procedure2()`. Please look there for further information.

`name` : | the name of the procedure to run
`n_return_vals` : | return location for the number of return values
`...` : | list of procedure parameters
Returns : | the procedure's return values.

### gimp_run_procedure2 ()

    GimpParam *         gimp_run_procedure2                 (const gchar *name,
                                                             gint *n_return_vals,
                                                             gint n_params,
                                                             const GimpParam *params);

This function calls a GIMP procedure and returns its return values. To get more information about the available procedures and the parameters they expect, please have a look at the Procedure Browser as found in the Xtns menu in GIMP's toolbox.

As soon as you don't need the return values any longer, you should free them using `gimp_destroy_params()`.

`name` : | the name of the procedure to run
`n_return_vals` : | return location for the number of return values
`n_params` : | the number of parameters the procedure takes.
`params` : | the procedure's parameters array.
Returns : | the procedure's return values.

### gimp_destroy_params ()

    void                gimp_destroy_params                 (GimpParam *params,
                                                             gint n_params);

Destroys a GimpParam array as returned by `gimp_run_procedure()` or `gimp_run_procedure2()`.

`params` : | the GimpParam array to destroy
`n_params` : | the number of elements in the array

### gimp_destroy_paramdefs ()

    void                gimp_destroy_paramdefs              (GimpParamDef *paramdefs,
                                                             gint n_params);

Destroys a GimpParamDef array as returned by `gimp_procedural_db_proc_info()`.

`paramdefs` : | the GimpParamDef array to destroy
`n_params` : | the number of elements in the array

### gimp_get_pdb_error ()

    const gchar *       gimp_get_pdb_error                  (void);

Retrieves the error message from the last procedure call.

If a procedure call fails, then it might pass an error message with the return values. Plug-ins that are using the libgimp C wrappers don't access the procedure return values directly. Thus ligimp stores the error message and makes it available with this function. The next procedure call unsets the error message again.

The returned string is owned by libgimp and must not be freed or modified.

Returns : | the error message

Since GIMP 2.6

### gimp_tile_width ()

    guint               gimp_tile_width                     (void);

Returns the tile width GIMP is using.

This is a constant value given at plug-in configuration time.

Returns : | the tile_width

### gimp_tile_height ()

    guint               gimp_tile_height                    (void);

Returns the tile height GIMP is using.

This is a constant value given at plug-in configuration time.

Returns : | the tile_height

### gimp_shm_ID ()

    gint                gimp_shm_ID                         (void);

Returns the shared memory ID used for passing tile data between the GIMP core and the plug-in.

This is a constant value given at plug-in configuration time.

Returns : | the shared memory ID

### gimp_shm_addr ()

    guchar *            gimp_shm_addr                       (void);

Returns the address of the shared memory segment used for passing tile data between the GIMP core and the plug-in.

This is a constant value given at plug-in configuration time.

Returns : | the shared memory address

### gimp_gamma ()

    gdouble             gimp_gamma                          (void);

Returns the global gamma value GIMP and all its plug-ins should use.

This is a constant value given at plug-in configuration time.

NOTE: This function will always return 2.2, the gamma value for sRGB. There's currently no way to change this and all operations should assume that pixel data is in the sRGB colorspace.

Returns : | the gamma value

### gimp_install_cmap ()

    gboolean            gimp_install_cmap                   (void);

Returns whether or not the plug-in should allocate an own colormap when running on an 8 bit display. See also: `gimp_min_colors()`.

This is a constant value given at plug-in configuration time.

Returns : | the install_cmap boolean

### gimp_min_colors ()

    gint                gimp_min_colors                     (void);

Returns the minimum number of colors to use when allocating an own colormap on 8 bit displays.

This is a constant value given at plug-in configuration time.

See also: `gimp_install_cmap()`

Returns : | the minimum number of colors to allocate

### gimp_show_tool_tips ()

    gboolean            gimp_show_tool_tips                 (void);

Returns whether or not the plug-in should show tool-tips.

This is a constant value given at plug-in configuration time.

Returns : | the show_tool_tips boolean

### gimp_show_help_button ()

    gboolean            gimp_show_help_button               (void);

Returns whether or not GimpDialog should automatically add a help button if help_func and help_id are given.

This is a constant value given at plug-in configuration time.

Returns : | the show_help_button boolean

Since GIMP 2.2

### gimp_check_size ()

    GimpCheckSize       gimp_check_size                     (void);

Returns the size of the checkerboard to be used in previews.

This is a constant value given at plug-in configuration time.

Returns : | the check_size value

Since GIMP 2.2

### gimp_check_type ()

    GimpCheckType       gimp_check_type                     (void);

Returns the type of the checkerboard to be used in previews.

This is a constant value given at plug-in configuration time.

Returns : | the check_type value

Since GIMP 2.2

### gimp_default_display ()

    gint32              gimp_default_display                (void);

Returns the default display ID. This corresponds to the display the running procedure's menu entry was invoked from.

This is a constant value given at plug-in configuration time.

Returns : | the default display ID

### gimp_wm_class ()

    const gchar *       gimp_wm_class                       (void);

Returns the window manager class to be used for plug-in windows.

This is a constant value given at plug-in configuration time.

Returns : | the window manager class

### gimp_display_name ()

    const gchar *       gimp_display_name                   (void);

Returns the display to be used for plug-in windows.

This is a constant value given at plug-in configuration time.

Returns : | the display name

### gimp_monitor_number ()

    gint                gimp_monitor_number                 (void);

Returns the monitor number to be used for plug-in windows.

This is a constant value given at plug-in configuration time.

Returns : | the monitor number

### gimp_user_time ()

    guint32             gimp_user_time                      (void);

Returns the timestamp of the user interaction that should be set on the plug-in window. This is handled transparently, plug-in authors do not have to care about it.

This is a constant value given at plug-in configuration time.

Returns : | timestamp for plug-in window

Since GIMP 2.6

### gimp_get_progname ()

    const gchar *       gimp_get_progname                   (void);

Returns the plug-in's executable name.

Returns : | the executable name

### gimp_extension_enable ()

    void                gimp_extension_enable               (void);

Enables asynchronous processing of messages from the main GIMP application.

Normally, a plug-in is not called by GIMP except for the call to the procedure it implements. All subsequent communication is triggered by the plug-in and all messages sent from GIMP to the plug-in are just answers to requests the plug-in made.

If the plug-in however registered temporary procedures using `gimp_install_temp_proc()`, it needs to be able to receive requests to execute them. Usually this will be done by running `gimp_extension_process()` in an endless loop.

If the plug-in cannot use `gimp_extension_process()`, i.e. if it has a GUI and is hanging around in a GMainLoop, it must call `gimp_extension_enable()`.

Note that the plug-in does not need to be a GIMP_EXTENSION to register temporary procedures.

See also: `gimp_install_procedure()`, `gimp_install_temp_proc()`

### gimp_extension_ack ()

    void                gimp_extension_ack                  (void);

Notify the main GIMP application that the extension has been properly initialized and is ready to run.

This function must be called from every procedure that was registered as GIMP_EXTENSION.

Subsequently, extensions can process temporary procedure run requests using either `gimp_extension_enable()` or `gimp_extension_process()`.

See also: `gimp_install_procedure()`, `gimp_install_temp_proc()`

### gimp_extension_process ()

    void                gimp_extension_process              (guint timeout);

Processes one message sent by GIMP and returns.

Call this function in an endless loop after calling `gimp_extension_ack()` to process requests for running temporary procedures.

See `gimp_extension_enable()` for an asynchronous way of doing the same if running an endless loop is not an option.

See also: `gimp_install_procedure()`, `gimp_install_temp_proc()`

`timeout` : | The timeout (in ms) to use for the `select()` call.

### gimp_parasite_find ()

    GimpParasite*       gimp_parasite_find                  (const gchar *name);

Look up a global parasite.

Finds and returns the global parasite that was previously attached.

`name` : | The name of the parasite to find.
Returns : | The found parasite.

### gimp_parasite_list ()

    gboolean            gimp_parasite_list                  (gint *num_parasites,
                                                             gchar ***parasites);

List all parasites.

Returns a list of all currently attached global parasites.

`num_parasites` : | The number of attached parasites.
`parasites` : | The names of currently attached parasites.
Returns : | TRUE on success.

### gimp_parasite_attach ()

    gboolean            gimp_parasite_attach                (const GimpParasite *parasite);

Add a global parasite.

This procedure attaches a global parasite. It has no return values.

`parasite` : | The parasite to attach.
Returns : | TRUE on success.

### gimp_parasite_detach ()

    gboolean            gimp_parasite_detach                (const gchar *name);

Removes a global parasite.

This procedure detaches a global parasite from. It has no return values.

`name` : | The name of the parasite to detach.
Returns : | TRUE on success.

### gimp_attach_new_parasite ()

    gboolean            gimp_attach_new_parasite            (const gchar *name,
                                                             gint flags,
                                                             gint size,
                                                             gconstpointer data);

Convenience function that creates a parasite and attaches it to GIMP.

`name` : | the name of the GimpParasite to create and attach.
`flags` : | the flags set on the GimpParasite.
`size` : | the size of the parasite data in bytes.
`data` : | a pointer to the data attached with the GimpParasite.
Returns : | TRUE on successful creation and attachment of the new parasite. See Also: `gimp_parasite_attach()`