gimplayer: GIMP Library Reference Manual

+ + +

gimplayer

gimplayer — Operations on a single layer.

Functions

++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

+gint32 +	+gimp_layer_new () +
+gint32 +	+gimp_layer_new_from_drawable () +
+gint32 +	+gimp_layer_new_from_visible () +
+gint32 +	+gimp_layer_new_from_pixbuf () +
+gint32 +	+gimp_layer_new_from_surface () +
+gint32 +	+gimp_layer_group_new () +
+gint32 +	+gimp_layer_copy () +
+gboolean +	+gimp_layer_scale () +
+gboolean +	+gimp_layer_scale_full () +
+gboolean +	+gimp_layer_resize () +
+gboolean +	+gimp_layer_resize_to_image_size () +
+gboolean +	+gimp_layer_translate () +
+gboolean +	+gimp_layer_add_alpha () +
+gboolean +	+gimp_layer_flatten () +
+gboolean +	+gimp_layer_set_offsets () +
+gint32 +	+gimp_layer_create_mask () +
+gint32 +	+gimp_layer_from_mask () +
+gint32 +	+gimp_layer_get_mask () +
+gboolean +	+gimp_layer_add_mask () +
+gboolean +	+gimp_layer_remove_mask () +
+gboolean +	+gimp_layer_is_floating_sel () +
+gboolean +	+gimp_layer_get_lock_alpha () +
+gboolean +	+gimp_layer_set_lock_alpha () +
+gboolean +	+gimp_layer_get_preserve_trans () +
+gboolean +	+gimp_layer_set_preserve_trans () +
+gboolean +	+gimp_layer_get_apply_mask () +
+gboolean +	+gimp_layer_set_apply_mask () +
+gboolean +	+gimp_layer_get_show_mask () +
+gboolean +	+gimp_layer_set_show_mask () +
+gboolean +	+gimp_layer_get_edit_mask () +
+gboolean +	+gimp_layer_set_edit_mask () +
+gdouble +	+gimp_layer_get_opacity () +
+gboolean +	+gimp_layer_set_opacity () +
+GimpLayerMode +	+gimp_layer_get_mode () +
+gboolean +	+gimp_layer_set_mode () +
+GimpLayerColorSpace +	+gimp_layer_get_blend_space () +
+gboolean +	+gimp_layer_set_blend_space () +
+GimpLayerColorSpace +	+gimp_layer_get_composite_space () +
+gboolean +	+gimp_layer_set_composite_space () +
+GimpLayerCompositeMode +	+gimp_layer_get_composite_mode () +
+gboolean +	+gimp_layer_set_composite_mode () +

Description

Operations on a single layer.

Functions

gimp_layer_new ()

gint32
+gimp_layer_new (gint32 image_ID,
+                const gchar *name,
+                gint width,
+                gint height,
+                GimpImageType type,
+                gdouble opacity,
+                GimpLayerMode mode);

Create a new layer.

This procedure creates a new layer with the specified width, height, +and type. Name, opacity, and mode are also supplied parameters. The +new layer still needs to be added to the image, as this is not +automatic. Add the new layer with the gimp_image_insert_layer() +command. Other attributes such as layer mask modes, and offsets +should be set with explicit procedure calls.

Parameters

+++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

image_ID	The image to which to add the layer.
name	The layer name.
width	The layer width.
height	The layer height.
type	The layer type.
opacity	The layer opacity.
mode	The layer combination mode.

Returns

The newly created layer.

gimp_layer_new_from_drawable ()

gint32
+gimp_layer_new_from_drawable (gint32 drawable_ID,
+                              gint32 dest_image_ID);

Create a new layer by copying an existing drawable.

This procedure creates a new layer as a copy of the specified +drawable. The new layer still needs to be added to the image, as +this is not automatic. Add the new layer with the +gimp_image_insert_layer() command. Other attributes such as layer +mask modes, and offsets should be set with explicit procedure calls.

Parameters

+++++ + + + + + + + + + + + + +

drawable_ID	The source drawable from where the new layer is copied.
dest_image_ID	The destination image to which to add the layer.

Returns

The newly copied layer.

gimp_layer_new_from_visible ()

gint32
+gimp_layer_new_from_visible (gint32 image_ID,
+                             gint32 dest_image_ID,
+                             const gchar *name);

Create a new layer from what is visible in an image.

This procedure creates a new layer from what is visible in the given +image. The new layer still needs to be added to the destination +image, as this is not automatic. Add the new layer with the +gimp_image_insert_layer() command. Other attributes such as layer +mask modes, and offsets should be set with explicit procedure calls.

Parameters

+++++ + + + + + + + + + + + + + + + + + +

image_ID	The source image from where the content is copied.
dest_image_ID	The destination image to which to add the layer.
name	The layer name.

Returns

The newly created layer.

Since: 2.6

gimp_layer_new_from_pixbuf ()

gint32
+gimp_layer_new_from_pixbuf (gint32 image_ID,
+                            const gchar *name,
+                            GdkPixbuf *pixbuf,
+                            gdouble opacity,
+                            GimpLayerMode mode,
+                            gdouble progress_start,
+                            gdouble progress_end);

Create a new layer from a GdkPixbuf.

This procedure creates a new layer from the given GdkPixbuf. The +image has to be an RGB image and just like with gimp_layer_new() +you will still need to add the layer to it.

If you pass progress_end + > progress_start + to this function, +gimp_progress_update() will be called for. You have to call +gimp_progress_init() beforehand then.

Parameters

+++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

image_ID	The RGB image to which to add the layer.
name	The layer name.
pixbuf	A GdkPixbuf.
opacity	The layer opacity.
mode	The layer combination mode.
progress_start	start of progress
progress_end	end of progress

Returns

The newly created layer.

Since: 2.4

gimp_layer_new_from_surface ()

gint32
+gimp_layer_new_from_surface (gint32 image_ID,
+                             const gchar *name,
+                             cairo_surface_t *surface,
+                             gdouble progress_start,
+                             gdouble progress_end);

Create a new layer from a cairo_surface_t.

This procedure creates a new layer from the given +cairo_surface_t. The image has to be an RGB image and just like +with gimp_layer_new() you will still need to add the layer to it.

If you pass progress_end + > progress_start + to this function, +gimp_progress_update() will be called for. You have to call +gimp_progress_init() beforehand then.

Parameters

+++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + +

image_ID	The RGB image to which to add the layer.
name	The layer name.
surface	A Cairo image surface.
progress_start	start of progress
progress_end	end of progress

Returns

The newly created layer.

Since: 2.8

gimp_layer_group_new ()

gint32
+gimp_layer_group_new (gint32 image_ID);

Create a new layer group.

This procedure creates a new layer group. Attributes such as layer +mode and opacity should be set with explicit procedure calls. Add +the new layer group (which is a kind of layer) with the +gimp_image_insert_layer() command. +Other procedures useful with layer groups: +gimp_image_reorder_item(), gimp_item_get_parent(), +gimp_item_get_children(), gimp_item_is_group().

Parameters

+++++ + + + + + +

image_ID

The image to which to add the layer group.

Returns

The newly created layer group.

Since: 2.8

gimp_layer_copy ()

gint32
+gimp_layer_copy (gint32 layer_ID);

Copy a layer.

This procedure copies the specified layer and returns the copy. The +newly copied layer is for use within the original layer's image. It +should not be subsequently added to any other image.

Parameters

+++++ + + + + + +

layer_ID

The layer to copy.

Returns

The newly copied layer.

gimp_layer_scale ()

gboolean
+gimp_layer_scale (gint32 layer_ID,
+                  gint new_width,
+                  gint new_height,
+                  gboolean local_origin);

Scale the layer using the default interpolation method.

This procedure scales the layer so that its new width and height are +equal to the supplied parameters. The 'local-origin' parameter +specifies whether to scale from the center of the layer, or from the +image origin. This operation only works if the layer has been added +to an image. The interpolation method used can be set with +gimp_context_set_interpolation().

Parameters

+++++ + + + + + + + + + + + + + + + + + + + + + + +

layer_ID	The layer.
new_width	New layer width.
new_height	New layer height.
local_origin	Use a local origin (as opposed to the image origin).

Returns

TRUE on success.

gimp_layer_scale_full ()

gboolean
+gimp_layer_scale_full (gint32 layer_ID,
+                       gint new_width,
+                       gint new_height,
+                       gboolean local_origin,
+                       GimpInterpolationType interpolation);

gimp_layer_scale_full is deprecated and should not be used in newly-written code.

Use gimp_layer_scale() instead.

Parameters

+++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + +

layer_ID	The layer.
new_width	New layer width.
new_height	New layer height.
local_origin	Use a local origin (as opposed to the image origin).
interpolation	Type of interpolation.

Returns

TRUE on success.

Since: 2.6

gimp_layer_resize ()

gboolean
+gimp_layer_resize (gint32 layer_ID,
+                   gint new_width,
+                   gint new_height,
+                   gint offx,
+                   gint offy);

Resize the layer to the specified extents.

This procedure resizes the layer so that its new width and height +are equal to the supplied parameters. Offsets are also provided +which describe the position of the previous layer's content. This +operation only works if the layer has been added to an image.

Parameters

+++++ + + + + + + + + + + + + + + + + + + + + + + + + + + + +

layer_ID	The layer.
new_width	New layer width.
new_height	New layer height.
offx	x offset between upper left corner of old and new layers: (old - new).
offy	y offset between upper left corner of old and new layers: (old - new).

Returns

TRUE on success.

gimp_layer_resize_to_image_size ()

gboolean
+gimp_layer_resize_to_image_size (gint32 layer_ID);

Resize a layer to the image size.

This procedure resizes the layer so that it's new width and height +are equal to the width and height of its image container.

Parameters

+++++ + + + + + +

layer_ID

The layer to resize.

Returns

TRUE on success.

gimp_layer_translate ()

gboolean
+gimp_layer_translate (gint32 layer_ID,
+                      gint offx,
+                      gint offy);

gimp_layer_translate is deprecated and should not be used in newly-written code.

Use gimp_item_transform_translate() instead.

Translate the layer by the specified offsets.

This procedure translates the layer by the amounts specified in the +x and y arguments. These can be negative, and are considered offsets +from the current position. This command only works if the layer has +been added to an image. All additional layers contained in the image +which have the linked flag set to TRUE w ill also be translated by +the specified offsets.

Parameters

+++++ + + + + + + + + + + + + + + + + + +

layer_ID	The layer.
offx	Offset in x direction.
offy	Offset in y direction.

Returns

TRUE on success.

gimp_layer_add_alpha ()

gboolean
+gimp_layer_add_alpha (gint32 layer_ID);

Add an alpha channel to the layer if it doesn't already have one.

This procedure adds an additional component to the specified layer +if it does not already possess an alpha channel. An alpha channel +makes it possible to clear and erase to transparency, instead of the +background color. This transforms layers of type RGB to RGBA, GRAY +to GRAYA, and INDEXED to INDEXEDA.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

TRUE on success.

gimp_layer_flatten ()

gboolean
+gimp_layer_flatten (gint32 layer_ID);

Remove the alpha channel from the layer if it has one.

This procedure removes the alpha channel from a layer, blending all +(partially) transparent pixels in the layer against the background +color. This transforms layers of type RGBA to RGB, GRAYA to GRAY, +and INDEXEDA to INDEXED.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

TRUE on success.

Since: 2.4

gimp_layer_set_offsets ()

gboolean
+gimp_layer_set_offsets (gint32 layer_ID,
+                        gint offx,
+                        gint offy);

Set the layer offsets.

This procedure sets the offsets for the specified layer. The offsets +are relative to the image origin and can be any values. This +operation is valid only on layers which have been added to an image.

Parameters

+++++ + + + + + + + + + + + + + + + + + +

layer_ID	The layer.
offx	Offset in x direction.
offy	Offset in y direction.

Returns

TRUE on success.

gimp_layer_create_mask ()

gint32
+gimp_layer_create_mask (gint32 layer_ID,
+                        GimpAddMaskType mask_type);

Create a layer mask for the specified layer.

This procedure creates a layer mask for the specified layer. +Layer masks serve as an additional alpha channel for a layer. +Different types of masks are allowed for initialisation:

white mask (leaves the layer fully visible);
black mask (gives the layer complete transparency);
the layer's alpha channel (either a copy, or a transfer, which +leaves the layer fully visible, but which may be more useful than a +white mask);
the current selection;
a grayscale copy of the layer;
or a copy of the active channel.

The layer mask still needs to be added to the layer. This can be +done with a call to gimp_layer_add_mask().

gimp_layer_create_mask() will fail if there are no active channels +on the image, when called with 'ADD-CHANNEL-MASK'. It will return a +black mask when called with 'ADD-ALPHA-MASK' or +'ADD-ALPHA-TRANSFER-MASK' on a layer with no alpha channels, or with +'ADD-SELECTION-MASK' when there is no selection on the image.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer to which to add the mask.
mask_type	The type of mask.

Returns

The newly created mask.

gimp_layer_from_mask ()

gint32
+gimp_layer_from_mask (gint32 mask_ID);

Get the specified mask's layer.

This procedure returns the specified mask's layer , or -1 if none +exists.

Parameters

+++++ + + + + + +

mask_ID

Mask for which to return the layer.

Returns

The mask's layer.

Since: 2.2

gimp_layer_get_mask ()

gint32
+gimp_layer_get_mask (gint32 layer_ID);

Get the specified layer's mask if it exists.

This procedure returns the specified layer's mask, or -1 if none +exists.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer mask.

gimp_layer_add_mask ()

gboolean
+gimp_layer_add_mask (gint32 layer_ID,
+                     gint32 mask_ID);

Add a layer mask to the specified layer.

This procedure adds a layer mask to the specified layer. Layer masks +serve as an additional alpha channel for a layer. This procedure +will fail if a number of prerequisites aren't met. The layer cannot +already have a layer mask. The specified mask must exist and have +the same dimensions as the layer. The layer must have been created +for use with the specified image and the mask must have been created +with the procedure 'gimp-layer-create-mask'.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer to receive the mask.
mask_ID	The mask to add to the layer.

Returns

TRUE on success.

gimp_layer_remove_mask ()

gboolean
+gimp_layer_remove_mask (gint32 layer_ID,
+                        GimpMaskApplyMode mode);

Remove the specified layer mask from the layer.

This procedure removes the specified layer mask from the layer. If +the mask doesn't exist, an error is returned.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer from which to remove mask.
mode	Removal mode.

Returns

TRUE on success.

gimp_layer_is_floating_sel ()

gboolean
+gimp_layer_is_floating_sel (gint32 layer_ID);

Is the specified layer a floating selection?

This procedure returns whether the layer is a floating selection. +Floating selections are special cases of layers which are attached +to a specific drawable.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

TRUE if the layer is a floating selection.

gimp_layer_get_lock_alpha ()

gboolean
+gimp_layer_get_lock_alpha (gint32 layer_ID);

Get the lock alpha channel setting of the specified layer.

This procedure returns the specified layer's lock alpha channel +setting.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer's lock alpha channel setting.

gimp_layer_set_lock_alpha ()

gboolean
+gimp_layer_set_lock_alpha (gint32 layer_ID,
+                           gboolean lock_alpha);

Set the lock alpha channel setting of the specified layer.

This procedure sets the specified layer's lock alpha channel +setting.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
lock_alpha	The new layer's lock alpha channel setting.

Returns

TRUE on success.

gimp_layer_get_preserve_trans ()

gboolean
+gimp_layer_get_preserve_trans (gint32 layer_ID);

gimp_layer_get_preserve_trans is deprecated and should not be used in newly-written code.

This procedure is deprecated! Use gimp_layer_get_lock_alpha() instead.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer's preserve transperancy setting.

gimp_layer_set_preserve_trans ()

gboolean
+gimp_layer_set_preserve_trans (gint32 layer_ID,
+                               gboolean preserve_trans);

gimp_layer_set_preserve_trans is deprecated and should not be used in newly-written code.

This procedure is deprecated! Use gimp_layer_set_lock_alpha() instead.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
preserve_trans	The new layer's preserve transperancy setting.

Returns

TRUE on success.

gimp_layer_get_apply_mask ()

gboolean
+gimp_layer_get_apply_mask (gint32 layer_ID);

Get the apply mask setting of the specified layer.

This procedure returns the specified layer's apply mask setting. If +the value is TRUE, then the layer mask for this layer is currently +being composited with the layer's alpha channel.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer's apply mask setting.

gimp_layer_set_apply_mask ()

gboolean
+gimp_layer_set_apply_mask (gint32 layer_ID,
+                           gboolean apply_mask);

Set the apply mask setting of the specified layer.

This procedure sets the specified layer's apply mask setting. This +controls whether the layer's mask is currently affecting the alpha +channel. If there is no layer mask, this function will return an +error.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
apply_mask	The new layer's apply mask setting.

Returns

TRUE on success.

gimp_layer_get_show_mask ()

gboolean
+gimp_layer_get_show_mask (gint32 layer_ID);

Get the show mask setting of the specified layer.

This procedure returns the specified layer's show mask setting. This +controls whether the layer or its mask is visible. TRUE indicates +that the mask should be visible. If the layer has no mask, then this +function returns an error.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer's show mask setting.

gimp_layer_set_show_mask ()

gboolean
+gimp_layer_set_show_mask (gint32 layer_ID,
+                          gboolean show_mask);

Set the show mask setting of the specified layer.

This procedure sets the specified layer's show mask setting. This +controls whether the layer or its mask is visible. TRUE indicates +that the mask should be visible. If there is no layer mask, this +function will return an error.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
show_mask	The new layer's show mask setting.

Returns

TRUE on success.

gimp_layer_get_edit_mask ()

gboolean
+gimp_layer_get_edit_mask (gint32 layer_ID);

Get the edit mask setting of the specified layer.

This procedure returns the specified layer's edit mask setting. If +the value is TRUE, then the layer mask for this layer is currently +active, and not the layer.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer's edit mask setting.

gimp_layer_set_edit_mask ()

gboolean
+gimp_layer_set_edit_mask (gint32 layer_ID,
+                          gboolean edit_mask);

Set the edit mask setting of the specified layer.

This procedure sets the specified layer's edit mask setting. This +controls whether the layer or it's mask is currently active for +editing. If the specified layer has no layer mask, then this +procedure will return an error.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
edit_mask	The new layer's edit mask setting.

Returns

TRUE on success.

gimp_layer_get_opacity ()

gdouble
+gimp_layer_get_opacity (gint32 layer_ID);

Get the opacity of the specified layer.

This procedure returns the specified layer's opacity.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer opacity.

gimp_layer_set_opacity ()

gboolean
+gimp_layer_set_opacity (gint32 layer_ID,
+                        gdouble opacity);

Set the opacity of the specified layer.

This procedure sets the specified layer's opacity.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
opacity	The new layer opacity.

Returns

TRUE on success.

gimp_layer_get_mode ()

GimpLayerMode
+gimp_layer_get_mode (gint32 layer_ID);

Get the combination mode of the specified layer.

This procedure returns the specified layer's combination mode.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer combination mode.

gimp_layer_set_mode ()

gboolean
+gimp_layer_set_mode (gint32 layer_ID,
+                     GimpLayerMode mode);

Set the combination mode of the specified layer.

This procedure sets the specified layer's combination mode.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
mode	The new layer combination mode.

Returns

TRUE on success.

gimp_layer_get_blend_space ()

GimpLayerColorSpace
+gimp_layer_get_blend_space (gint32 layer_ID);

Get the blend space of the specified layer.

This procedure returns the specified layer's blend space.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer blend space.

Since: 2.10

gimp_layer_set_blend_space ()

gboolean
+gimp_layer_set_blend_space (gint32 layer_ID,
+                            GimpLayerColorSpace blend_space);

Set the blend space of the specified layer.

This procedure sets the specified layer's blend space.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
blend_space	The new layer blend space.

Returns

TRUE on success.

Since: 2.10

gimp_layer_get_composite_space ()

GimpLayerColorSpace
+gimp_layer_get_composite_space (gint32 layer_ID);

Get the composite space of the specified layer.

This procedure returns the specified layer's composite space.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer composite space.

Since: 2.10

gimp_layer_set_composite_space ()

gboolean
+gimp_layer_set_composite_space (gint32 layer_ID,
+                                GimpLayerColorSpace composite_space);

Set the composite space of the specified layer.

This procedure sets the specified layer's composite space.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
composite_space	The new layer composite space.

Returns

TRUE on success.

Since: 2.10

gimp_layer_get_composite_mode ()

GimpLayerCompositeMode
+gimp_layer_get_composite_mode (gint32 layer_ID);

Get the composite mode of the specified layer.

This procedure returns the specified layer's composite mode.

Parameters

+++++ + + + + + +

layer_ID

The layer.

Returns

The layer composite mode.

Since: 2.10

gimp_layer_set_composite_mode ()

gboolean
+gimp_layer_set_composite_mode (gint32 layer_ID,
+                               GimpLayerCompositeMode composite_mode);

Set the composite mode of the specified layer.

This procedure sets the specified layer's composite mode.

Parameters

+++++ + + + + + + + + + + + + +

layer_ID	The layer.
composite_mode	The new layer composite mode.

Returns

TRUE on success.

Since: 2.10