gimpimageundo

gimpimageundo — Control of image undo/redo.

Functions

Description

Control of image undo/redo.

Functions

gimp_image_undo_group_start ()

gboolean
gimp_image_undo_group_start (gint32 image_ID);

Starts a group undo.

This function is used to start a group undo--necessary for logically combining two or more undo operations into a single operation. This call must be used in conjunction with a gimp_image_undo_group_end() call.

Parameters

image_ID

The ID of the image in which to open an undo group.

 

Returns

TRUE on success.


gimp_image_undo_group_end ()

gboolean
gimp_image_undo_group_end (gint32 image_ID);

Finish a group undo.

This function must be called once for each gimp_image_undo_group_start() call that is made.

Parameters

image_ID

The ID of the image in which to close an undo group.

 

Returns

TRUE on success.


gimp_image_undo_is_enabled ()

gboolean
gimp_image_undo_is_enabled (gint32 image_ID);

Check if the image's undo stack is enabled.

This procedure checks if the image's undo stack is currently enabled or disabled. This is useful when several plug-ins or scripts call each other and want to check if their caller has already used gimp_image_undo_disable() or gimp_image_undo_freeze().

Parameters

image_ID

The image.

 

Returns

TRUE if undo is enabled for this image.


gimp_image_undo_disable ()

gboolean
gimp_image_undo_disable (gint32 image_ID);

Disable the image's undo stack.

This procedure disables the image's undo stack, allowing subsequent operations to ignore their undo steps. This is generally called in conjunction with gimp_image_undo_enable() to temporarily disable an image undo stack. This is advantageous because saving undo steps can be time and memory intensive.

Parameters

image_ID

The image.

 

Returns

TRUE if the image undo has been disabled.


gimp_image_undo_enable ()

gboolean
gimp_image_undo_enable (gint32 image_ID);

Enable the image's undo stack.

This procedure enables the image's undo stack, allowing subsequent operations to store their undo steps. This is generally called in conjunction with gimp_image_undo_disable() to temporarily disable an image undo stack.

Parameters

image_ID

The image.

 

Returns

TRUE if the image undo has been enabled.


gimp_image_undo_freeze ()

gboolean
gimp_image_undo_freeze (gint32 image_ID);

Freeze the image's undo stack.

This procedure freezes the image's undo stack, allowing subsequent operations to ignore their undo steps. This is generally called in conjunction with gimp_image_undo_thaw() to temporarily disable an image undo stack. This is advantageous because saving undo steps can be time and memory intensive. gimp_image_undo_freeze() / gimp_image_undo_thaw() and gimp_image_undo_disable() / gimp_image_undo_enable() differ in that the former does not free up all undo steps when undo is thawed, so is more suited to interactive in-situ previews. It is important in this case that the image is back to the same state it was frozen in before thawing, else 'undo' behaviour is undefined.

Parameters

image_ID

The image.

 

Returns

TRUE if the image undo has been frozen.


gimp_image_undo_thaw ()

gboolean
gimp_image_undo_thaw (gint32 image_ID);

Thaw the image's undo stack.

This procedure thaws the image's undo stack, allowing subsequent operations to store their undo steps. This is generally called in conjunction with gimp_image_undo_freeze() to temporarily freeze an image undo stack. gimp_image_undo_thaw() does NOT free the undo stack as gimp_image_undo_enable() does, so is suited for situations where one wishes to leave the undo stack in the same state in which one found it despite non-destructively playing with the image in the meantime. An example would be in-situ plug-in previews. Balancing freezes and thaws and ensuring image consistency is the responsibility of the caller.

Parameters

image_ID

The image.

 

Returns

TRUE if the image undo has been thawed.