gimp/libgimp/gimpexportoptions.c

885 lines
25 KiB
C

/* LIBGIMP - The GIMP Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* gimpexportoptions.c
* Copyright (C) 2024 Alx Sa.
*
* This library is free software: you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <https://www.gnu.org/licenses/>.
*/
#include "config.h"
#include "gimp.h"
#include "gimpexportoptions.h"
#include "libgimp-intl.h"
/* export helper functions */
typedef void (* ExportFunc) (GimpImage *image,
GList **drawables);
/* the export action structure */
typedef struct
{
ExportFunc default_action;
ExportFunc alt_action;
const gchar *reason;
const gchar *possibilities[2];
gint choice;
} ExportAction;
/* the functions that do the actual export */
static void
export_merge (GimpImage *image,
GList **drawables)
{
GList *layers;
GList *iter;
gint32 nvisible = 0;
layers = gimp_image_list_layers (image);
for (iter = layers; iter; iter = g_list_next (iter))
{
if (gimp_item_get_visible (GIMP_ITEM (iter->data)))
nvisible++;
}
if (nvisible <= 1)
{
GimpLayer *transp;
GimpImageType layer_type;
/* if there is only one (or zero) visible layer, add a new
* transparent layer that has the same size as the canvas. The
* merge that follows will ensure that the offset, opacity and
* size are correct
*/
switch (gimp_image_get_base_type (image))
{
case GIMP_RGB:
layer_type = GIMP_RGBA_IMAGE;
break;
case GIMP_GRAY:
layer_type = GIMP_GRAYA_IMAGE;
break;
case GIMP_INDEXED:
layer_type = GIMP_INDEXEDA_IMAGE;
break;
default:
/* In case we add a new type in future. */
g_return_if_reached ();
}
transp = gimp_layer_new (image, "-",
gimp_image_get_width (image),
gimp_image_get_height (image),
layer_type,
100.0, GIMP_LAYER_MODE_NORMAL);
gimp_image_insert_layer (image, transp, NULL, 1);
gimp_selection_none (image);
gimp_drawable_edit_clear (GIMP_DRAWABLE (transp));
nvisible++;
}
if (nvisible > 1)
{
GimpLayer *merged;
merged = gimp_image_merge_visible_layers (image, GIMP_CLIP_TO_IMAGE);
g_return_if_fail (merged != NULL);
*drawables = g_list_prepend (NULL, merged);
g_list_free (layers);
layers = gimp_image_list_layers (image);
/* make sure that the merged drawable matches the image size */
if (gimp_drawable_get_width (GIMP_DRAWABLE (merged)) !=
gimp_image_get_width (image) ||
gimp_drawable_get_height (GIMP_DRAWABLE (merged)) !=
gimp_image_get_height (image))
{
gint off_x, off_y;
gimp_drawable_get_offsets (GIMP_DRAWABLE (merged), &off_x, &off_y);
gimp_layer_resize (merged,
gimp_image_get_width (image),
gimp_image_get_height (image),
off_x, off_y);
}
}
/* remove any remaining (invisible) layers */
for (iter = layers; iter; iter = iter->next)
{
if (! g_list_find (*drawables, iter->data))
gimp_image_remove_layer (image, iter->data);
}
g_list_free (layers);
}
static void
export_flatten (GimpImage *image,
GList **drawables)
{
GimpLayer *flattened;
flattened = gimp_image_flatten (image);
if (flattened != NULL)
*drawables = g_list_prepend (NULL, flattened);
}
static void
export_merge_layer_effects_rec (GList *layers)
{
GList *iter;
for (iter = layers; iter; iter = g_list_next (iter))
if (gimp_item_is_group (iter->data))
{
GList *children = gimp_item_list_children (iter->data);
export_merge_layer_effects_rec (children);
g_list_free (children);
}
else
{
gimp_drawable_merge_filters (GIMP_DRAWABLE (iter->data));
}
}
static void
export_merge_layer_effects (GimpImage *image,
GList **drawables)
{
GList *layers;
layers = gimp_image_list_layers (image);
export_merge_layer_effects_rec (layers);
g_list_free (layers);
}
static void
export_remove_alpha (GimpImage *image,
GList **drawables)
{
GList *layers;
GList *iter;
layers = gimp_image_list_layers (image);
for (iter = layers; iter; iter = iter->next)
{
if (gimp_drawable_has_alpha (GIMP_DRAWABLE (iter->data)))
gimp_layer_flatten (iter->data);
}
g_list_free (layers);
}
static void
export_apply_masks (GimpImage *image,
GList **drawables)
{
GList *layers;
GList *iter;
layers = gimp_image_list_layers (image);
for (iter = layers; iter; iter = iter->next)
{
GimpLayerMask *mask;
mask = gimp_layer_get_mask (iter->data);
if (mask)
{
/* we can't apply the mask directly to a layer group, so merge it
* first
*/
if (gimp_item_is_group (iter->data))
iter->data = gimp_group_layer_merge (iter->data);
gimp_layer_remove_mask (iter->data, GIMP_MASK_APPLY);
}
}
g_list_free (layers);
}
static void
export_convert_rgb (GimpImage *image,
GList **drawables)
{
gimp_image_convert_rgb (image);
}
static void
export_convert_grayscale (GimpImage *image,
GList **drawables)
{
gimp_image_convert_grayscale (image);
}
static void
export_convert_indexed (GimpImage *image,
GList **drawables)
{
GList *layers;
GList *iter;
gboolean has_alpha = FALSE;
/* check alpha */
layers = gimp_image_list_layers (image);
for (iter = *drawables; iter; iter = iter->next)
{
if (gimp_drawable_has_alpha (iter->data))
{
has_alpha = TRUE;
break;
}
}
if (layers || has_alpha)
gimp_image_convert_indexed (image,
GIMP_CONVERT_DITHER_NONE,
GIMP_CONVERT_PALETTE_GENERATE,
255, FALSE, FALSE, "");
else
gimp_image_convert_indexed (image,
GIMP_CONVERT_DITHER_NONE,
GIMP_CONVERT_PALETTE_GENERATE,
256, FALSE, FALSE, "");
g_list_free (layers);
}
static void
export_convert_bitmap (GimpImage *image,
GList **drawables)
{
if (gimp_image_get_base_type (image) == GIMP_INDEXED)
gimp_image_convert_rgb (image);
gimp_image_convert_indexed (image,
GIMP_CONVERT_DITHER_FS,
GIMP_CONVERT_PALETTE_GENERATE,
2, FALSE, FALSE, "");
}
static void
export_add_alpha (GimpImage *image,
GList **drawables)
{
GList *layers;
GList *iter;
layers = gimp_image_list_layers (image);
for (iter = layers; iter; iter = iter->next)
{
if (! gimp_drawable_has_alpha (GIMP_DRAWABLE (iter->data)))
gimp_layer_add_alpha (GIMP_LAYER (iter->data));
}
g_list_free (layers);
}
static void
export_crop_image (GimpImage *image,
GList **drawables)
{
gimp_image_crop (image,
gimp_image_get_width (image),
gimp_image_get_height (image),
0, 0);
}
static void
export_resize_image (GimpImage *image,
GList **drawables)
{
gimp_image_resize_to_layers (image);
}
static void
export_void (GimpImage *image,
GList **drawables)
{
/* do nothing */
}
/* a set of predefined actions */
static ExportAction export_action_merge =
{
export_merge,
NULL,
N_("%s plug-in can't handle layers"),
{ N_("Merge Visible Layers"), NULL },
0
};
static ExportAction export_action_merge_single =
{
export_merge,
NULL,
N_("%s plug-in can't handle layer offsets, size or opacity"),
{ N_("Merge Visible Layers"), NULL },
0
};
static ExportAction export_action_animate_or_merge =
{
NULL,
export_merge,
N_("%s plug-in can only handle layers as animation frames"),
{ N_("Save as Animation"), N_("Merge Visible Layers") },
0
};
static ExportAction export_action_animate_or_flatten =
{
NULL,
export_flatten,
N_("%s plug-in can only handle layers as animation frames"),
{ N_("Save as Animation"), N_("Flatten Image") },
0
};
static ExportAction export_action_merge_or_flatten =
{
export_flatten,
export_merge,
N_("%s plug-in can't handle layers"),
{ N_("Flatten Image"), N_("Merge Visible Layers") },
1
};
static ExportAction export_action_flatten =
{
export_flatten,
NULL,
N_("%s plug-in can't handle transparency"),
{ N_("Flatten Image"), NULL },
0
};
static ExportAction export_action_merge_layer_effects =
{
export_merge_layer_effects,
NULL,
N_("%s plug-in can't handle layer effects"),
{ N_("Merge Layer Effects"), NULL },
0
};
static ExportAction export_action_remove_alpha =
{
export_remove_alpha,
NULL,
N_("%s plug-in can't handle transparent layers"),
{ N_("Flatten Image"), NULL },
0
};
static ExportAction export_action_apply_masks =
{
export_apply_masks,
NULL,
N_("%s plug-in can't handle layer masks"),
{ N_("Apply Layer Masks"), NULL },
0
};
static ExportAction export_action_convert_rgb =
{
export_convert_rgb,
NULL,
N_("%s plug-in can only handle RGB images"),
{ N_("Convert to RGB"), NULL },
0
};
static ExportAction export_action_convert_grayscale =
{
export_convert_grayscale,
NULL,
N_("%s plug-in can only handle grayscale images"),
{ N_("Convert to Grayscale"), NULL },
0
};
static ExportAction export_action_convert_indexed =
{
export_convert_indexed,
NULL,
N_("%s plug-in can only handle indexed images"),
{ N_("Convert to Indexed using default settings\n"
"(Do it manually to tune the result)"), NULL },
0
};
static ExportAction export_action_convert_bitmap =
{
export_convert_bitmap,
NULL,
N_("%s plug-in can only handle bitmap (two color) indexed images"),
{ N_("Convert to Indexed using bitmap default settings\n"
"(Do it manually to tune the result)"), NULL },
0
};
static ExportAction export_action_convert_rgb_or_grayscale =
{
export_convert_rgb,
export_convert_grayscale,
N_("%s plug-in can only handle RGB or grayscale images"),
{ N_("Convert to RGB"), N_("Convert to Grayscale")},
0
};
static ExportAction export_action_convert_rgb_or_indexed =
{
export_convert_rgb,
export_convert_indexed,
N_("%s plug-in can only handle RGB or indexed images"),
{ N_("Convert to RGB"), N_("Convert to Indexed using default settings\n"
"(Do it manually to tune the result)")},
0
};
static ExportAction export_action_convert_indexed_or_grayscale =
{
export_convert_indexed,
export_convert_grayscale,
N_("%s plug-in can only handle grayscale or indexed images"),
{ N_("Convert to Indexed using default settings\n"
"(Do it manually to tune the result)"),
N_("Convert to Grayscale") },
0
};
static ExportAction export_action_add_alpha =
{
export_add_alpha,
NULL,
N_("%s plug-in needs an alpha channel"),
{ N_("Add Alpha Channel"), NULL},
0
};
static ExportAction export_action_crop_or_resize =
{
export_crop_image,
export_resize_image,
N_("%s plug-in needs to crop the layers to the image bounds"),
{ N_("Crop Layers"), N_("Resize Image to Layers")},
0
};
static ExportFunc
export_action_get_func (const ExportAction *action)
{
if (action->choice == 0 && action->default_action)
{
return action->default_action;
}
if (action->choice == 1 && action->alt_action)
{
return action->alt_action;
}
return export_void;
}
static void
export_action_perform (const ExportAction *action,
GimpImage *image,
GList **drawables)
{
export_action_get_func (action) (image, drawables);
}
/**
* gimp_export_options_get_image:
* @options: (transfer none): The #GimpExportOptions object.
* @image: (inout) (transfer none): the image.
*
* Takes an image to be exported, possibly creating a temporary copy
* modified according to export settings in @options (such as the
* capabilities of the export format).
*
* If necessary, a copy is created, converted and modified, @image
* changed to point to the new image and the procedure returns
* [enum@Gimp.ExportReturn.EXPORT].
* In this case, you must take care of deleting the created image using
* [method@Image.delete] once the image has been exported, unless you
* were planning to display it with [ctor@Display.new], or you will leak
* memory.
*
* If [enum@Gimp.ExportReturn.IGNORE] is returned, then @image is still the
* original image. You should neither modify it, nor should you delete
* it in the end. If you wish to temporarily modify the image before
* export anyway, call [method@Image.duplicate] when
* [enum@Gimp.ExportReturn.IGNORE] was returned.
*
* Returns: An enum of #GimpExportReturn.
*
* Since: 3.0
**/
GimpExportReturn
gimp_export_options_get_image (GimpExportOptions *options,
GimpImage **image)
{
GSList *actions = NULL;
GimpImageBaseType type;
GList *layers;
gint n_layers;
GList *iter;
GimpExportCapabilities capabilities = 0;
gboolean added_flatten = FALSE;
gboolean has_layer_masks = FALSE;
gboolean background_has_alpha = TRUE;
GimpExportReturn retval = GIMP_EXPORT_IGNORE;
g_return_val_if_fail (image && gimp_image_is_valid (*image), GIMP_EXPORT_IGNORE);
g_return_val_if_fail (GIMP_IS_EXPORT_OPTIONS (options), GIMP_EXPORT_IGNORE);
/* Get capabilities from ExportOptions */
g_object_get (options, "capabilities", &capabilities, NULL);
g_return_val_if_fail (capabilities & (GIMP_EXPORT_CAN_HANDLE_RGB |
GIMP_EXPORT_CAN_HANDLE_GRAY |
GIMP_EXPORT_CAN_HANDLE_INDEXED |
GIMP_EXPORT_CAN_HANDLE_BITMAP),
GIMP_EXPORT_IGNORE);
/* do some sanity checks */
if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
capabilities |= GIMP_EXPORT_CAN_HANDLE_ALPHA;
if (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS_AS_ANIMATION)
capabilities |= GIMP_EXPORT_CAN_HANDLE_LAYERS;
if (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYER_MASKS)
capabilities |= GIMP_EXPORT_CAN_HANDLE_LAYERS;
/* Merge down layer effects for non-project file formats */
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYER_EFFECTS))
actions = g_slist_prepend (actions, &export_action_merge_layer_effects);
/* check alpha and layer masks */
layers = gimp_image_list_layers (*image);
n_layers = g_list_length (layers);
if (n_layers < 1)
{
g_list_free (layers);
return FALSE;
}
for (iter = layers; iter; iter = iter->next)
{
GimpLayer *layer = GIMP_LAYER (iter->data);
if (gimp_drawable_has_alpha (GIMP_DRAWABLE (layer)))
{
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_ALPHA))
{
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
{
actions = g_slist_prepend (actions, &export_action_flatten);
added_flatten = TRUE;
break;
}
else
{
actions = g_slist_prepend (actions, &export_action_remove_alpha);
break;
}
}
}
else
{
/* If this is the last layer, it's visible and has no alpha
* channel, then the image has a "flat" background
*/
if (iter->next == NULL && gimp_item_get_visible (GIMP_ITEM (layer)))
background_has_alpha = FALSE;
if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
{
actions = g_slist_prepend (actions, &export_action_add_alpha);
break;
}
}
}
if (! added_flatten)
{
for (iter = layers; iter; iter = iter->next)
{
if (gimp_layer_get_mask (iter->data))
has_layer_masks = TRUE;
}
}
if (! added_flatten)
{
GimpLayer *layer = GIMP_LAYER (layers->data);
GList *children;
children = gimp_item_list_children (GIMP_ITEM (layer));
if ((capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS) &&
(capabilities & GIMP_EXPORT_NEEDS_CROP))
{
GeglRectangle image_bounds;
gboolean needs_crop = FALSE;
image_bounds.x = 0;
image_bounds.y = 0;
image_bounds.width = gimp_image_get_width (*image);
image_bounds.height = gimp_image_get_height (*image);
for (iter = layers; iter; iter = iter->next)
{
GimpDrawable *drawable = iter->data;
GeglRectangle layer_bounds;
gimp_drawable_get_offsets (drawable,
&layer_bounds.x, &layer_bounds.y);
layer_bounds.width = gimp_drawable_get_width (drawable);
layer_bounds.height = gimp_drawable_get_height (drawable);
if (! gegl_rectangle_contains (&image_bounds, &layer_bounds))
{
needs_crop = TRUE;
break;
}
}
if (needs_crop)
{
actions = g_slist_prepend (actions,
&export_action_crop_or_resize);
}
}
/* check if layer size != canvas size, opacity != 100%, or offsets != 0 */
if (g_list_length (layers) == 1 &&
! children &&
! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
{
GimpDrawable *drawable = layers->data;
gint offset_x;
gint offset_y;
gimp_drawable_get_offsets (drawable, &offset_x, &offset_y);
if ((gimp_layer_get_opacity (GIMP_LAYER (drawable)) < 100.0) ||
(gimp_image_get_width (*image) !=
gimp_drawable_get_width (drawable)) ||
(gimp_image_get_height (*image) !=
gimp_drawable_get_height (drawable)) ||
offset_x || offset_y)
{
if (capabilities & GIMP_EXPORT_CAN_HANDLE_ALPHA)
{
actions = g_slist_prepend (actions,
&export_action_merge_single);
}
else
{
actions = g_slist_prepend (actions,
&export_action_flatten);
}
}
}
/* check multiple layers */
else if (layers && layers->next != NULL)
{
if (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS_AS_ANIMATION)
{
if (background_has_alpha ||
capabilities & GIMP_EXPORT_NEEDS_ALPHA)
actions = g_slist_prepend (actions,
&export_action_animate_or_merge);
else
actions = g_slist_prepend (actions,
&export_action_animate_or_flatten);
}
else if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
{
if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
actions = g_slist_prepend (actions,
&export_action_merge);
else
actions = g_slist_prepend (actions,
&export_action_merge_or_flatten);
}
}
/* check for a single toplevel layer group */
else if (children)
{
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYERS))
{
if (capabilities & GIMP_EXPORT_NEEDS_ALPHA)
actions = g_slist_prepend (actions,
&export_action_merge);
else
actions = g_slist_prepend (actions,
&export_action_merge_or_flatten);
}
}
g_list_free (children);
/* check layer masks */
if (has_layer_masks &&
! (capabilities & GIMP_EXPORT_CAN_HANDLE_LAYER_MASKS))
actions = g_slist_prepend (actions, &export_action_apply_masks);
}
g_list_free (layers);
/* check the image type */
type = gimp_image_get_base_type (*image);
switch (type)
{
case GIMP_RGB:
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_RGB))
{
if ((capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED) &&
(capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY))
actions = g_slist_prepend (actions,
&export_action_convert_indexed_or_grayscale);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED)
actions = g_slist_prepend (actions,
&export_action_convert_indexed);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY)
actions = g_slist_prepend (actions,
&export_action_convert_grayscale);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_BITMAP)
actions = g_slist_prepend (actions,
&export_action_convert_bitmap);
}
break;
case GIMP_GRAY:
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY))
{
if ((capabilities & GIMP_EXPORT_CAN_HANDLE_RGB) &&
(capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED))
actions = g_slist_prepend (actions,
&export_action_convert_rgb_or_indexed);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_RGB)
actions = g_slist_prepend (actions,
&export_action_convert_rgb);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED)
actions = g_slist_prepend (actions,
&export_action_convert_indexed);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_BITMAP)
actions = g_slist_prepend (actions,
&export_action_convert_bitmap);
}
break;
case GIMP_INDEXED:
if (! (capabilities & GIMP_EXPORT_CAN_HANDLE_INDEXED))
{
if ((capabilities & GIMP_EXPORT_CAN_HANDLE_RGB) &&
(capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY))
actions = g_slist_prepend (actions,
&export_action_convert_rgb_or_grayscale);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_RGB)
actions = g_slist_prepend (actions,
&export_action_convert_rgb);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_GRAY)
actions = g_slist_prepend (actions,
&export_action_convert_grayscale);
else if (capabilities & GIMP_EXPORT_CAN_HANDLE_BITMAP)
{
gint n_colors;
n_colors = gimp_palette_get_color_count (gimp_image_get_palette (*image));
if (n_colors > 2)
actions = g_slist_prepend (actions,
&export_action_convert_bitmap);
}
}
break;
}
if (actions)
{
actions = g_slist_reverse (actions);
retval = GIMP_EXPORT_EXPORT;
}
else
{
retval = GIMP_EXPORT_IGNORE;
}
if (retval == GIMP_EXPORT_EXPORT)
{
GSList *list;
GList *drawables_in;
GList *drawables_out;
*image = gimp_image_duplicate (*image);
drawables_in = gimp_image_list_selected_layers (*image);
drawables_out = drawables_in;
gimp_image_undo_disable (*image);
for (list = actions; list; list = list->next)
{
export_action_perform (list->data, *image, &drawables_out);
if (drawables_in != drawables_out)
{
g_list_free (drawables_in);
drawables_in = drawables_out;
}
}
g_list_free (drawables_out);
}
g_slist_free (actions);
return retval;
}