gimp/libgimp/gimpgradientselectbutton.c

425 lines
12 KiB
C

/* LIBGIMP - The GIMP Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* gimpgradientselectbutton.c
* Copyright (C) 1998 Andy Thomas
*
* 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
* Library 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 <gegl.h>
#include <gtk/gtk.h>
#include "libgimpwidgets/gimpwidgets.h"
#include "gimp.h"
#include "gimpuitypes.h"
#include "gimpgradientselectbutton.h"
#include "gimpuimarshal.h"
#include "libgimp-intl.h"
/**
* SECTION: gimpgradientselectbutton
* @title: GimpGradientSelectButton
* @short_description: A button which pops up a gradient select dialog.
*
* A button which pops up a gradient select dialog.
**/
struct _GimpGradientSelectButton
{
/* !! Not a pointer, is contained. */
GimpResourceSelectButton parent_instance;
GtkWidget *button;
GtkWidget *drag_region_widget;
GtkWidget *preview; /* needed by draw. */
};
/* local function prototypes */
static void gimp_gradient_select_button_finalize (GObject *object);
static void gimp_gradient_select_button_embed_interior (GimpGradientSelectButton *self);
static void gimp_gradient_select_button_draw_interior (GimpResourceSelectButton *self);
static void gimp_gradient_select_button_set_drag_target (GimpGradientSelectButton *self);
static void gimp_gradient_select_preview_size_allocate (GtkWidget *widget,
GtkAllocation *allocation,
GimpGradientSelectButton *self);
static gboolean gimp_gradient_select_preview_draw_handler (GtkWidget *preview,
cairo_t *cr,
GimpGradientSelectButton *self);
static const GtkTargetEntry drag_target = { "application/x-gimp-gradient-name", 0 };
G_DEFINE_FINAL_TYPE (GimpGradientSelectButton,
gimp_gradient_select_button,
GIMP_TYPE_RESOURCE_SELECT_BUTTON)
/* Initial dimensions of widget. */
#define CELL_HEIGHT 18
#define CELL_WIDTH 84
static void
gimp_gradient_select_button_class_init (GimpGradientSelectButtonClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GimpResourceSelectButtonClass *superclass = GIMP_RESOURCE_SELECT_BUTTON_CLASS (klass);
g_debug ("%s", G_STRFUNC);
object_class->finalize = gimp_gradient_select_button_finalize;
/* Implement pure virtual functions. */
superclass->draw_interior = gimp_gradient_select_button_draw_interior;
/* Set data member of class. */
superclass->resource_type = GIMP_TYPE_GRADIENT;
}
static void
gimp_gradient_select_button_init (GimpGradientSelectButton *self)
{
g_debug ("%s", G_STRFUNC);
gimp_gradient_select_button_embed_interior (self);
gimp_gradient_select_button_set_drag_target (self);
gimp_resource_select_button_set_clickable (GIMP_RESOURCE_SELECT_BUTTON (self),
self->button);
}
/**
* gimp_gradient_select_button_new:
* @title: (nullable): Title of the dialog to use or %NULL to use the default title.
* @gradient: (nullable): Initial gradient.
*
* Creates a new #GtkWidget that lets a user choose a gradient.
* You can use this widget in a table in a plug-in dialog.
*
* Returns: A #GtkWidget that you can use in your UI.
*
* Since: 2.4
*/
GtkWidget *
gimp_gradient_select_button_new (const gchar *title,
GimpResource *gradient)
{
GtkWidget *self;
if (gradient == NULL)
{
g_debug ("%s defaulting gradient from context", G_STRFUNC);
gradient = GIMP_RESOURCE (gimp_context_get_gradient ());
}
g_assert (gradient != NULL);
/* This method is polymorphic, so a factory can call it, but requires gradient. */
g_return_val_if_fail (GIMP_IS_GRADIENT (gradient), NULL);
g_debug ("%s", G_STRFUNC);
if (title)
self = g_object_new (GIMP_TYPE_GRADIENT_SELECT_BUTTON,
"title", title,
"resource", gradient,
NULL);
else
self = g_object_new (GIMP_TYPE_GRADIENT_SELECT_BUTTON,
"resource", gradient,
NULL);
gimp_gradient_select_button_draw_interior (GIMP_RESOURCE_SELECT_BUTTON (self));
return self;
}
/**
* gimp_gradient_select_button_get_gradient:
* @self: A #GimpGradientSelectButton
*
* Gets the currently selected gradient.
*
* Returns: (transfer none): an internal copy of the gradient, which you must not free.
*
* Since: 2.4
*/
GimpGradient *
gimp_gradient_select_button_get_gradient (GimpGradientSelectButton *self)
{
g_debug ("%s", G_STRFUNC);
g_return_val_if_fail (GIMP_IS_GRADIENT_SELECT_BUTTON (self), NULL);
/* Delegate to super w upcast arg and downcast result. */
return (GimpGradient *) gimp_resource_select_button_get_resource ((GimpResourceSelectButton*) self);
}
/**
* gimp_gradient_select_button_set_gradient:
* @self: A #GimpGradientSelectButton
* @gradient: (nullable): Gradient to set.
*
* Sets the current gradient for the gradient select button.
*
* Since: 2.4
*/
void
gimp_gradient_select_button_set_gradient (GimpGradientSelectButton *self,
GimpGradient *gradient)
{
g_return_if_fail (GIMP_IS_GRADIENT_SELECT_BUTTON (self));
g_debug ("%s", G_STRFUNC);
/* Delegate to super with upcasts */
gimp_resource_select_button_set_resource (GIMP_RESOURCE_SELECT_BUTTON (self), GIMP_RESOURCE (gradient));
}
/* private functions */
static void
gimp_gradient_select_button_finalize (GObject *object)
{
g_debug ("%s", G_STRFUNC);
/* Nothing was allocated. */
G_OBJECT_CLASS (gimp_gradient_select_button_parent_class)->finalize (object);
}
static void
gimp_gradient_select_button_draw_interior (GimpResourceSelectButton *self)
{
GimpGradientSelectButton *self_as_gradient_select;
g_debug ("%s", G_STRFUNC);
g_return_if_fail (GIMP_IS_GRADIENT_SELECT_BUTTON (self));
self_as_gradient_select = GIMP_GRADIENT_SELECT_BUTTON (self);
/* Not actually draw, just queue. Continuation is the handler. */
gtk_widget_queue_draw (self_as_gradient_select->preview);
}
/* Get array of samples from self's gradient.
* Return array and size at given handles.
* Return success.
*/
static gboolean
get_gradient_data (GimpGradientSelectButton *self,
gint allocation_width,
gint *sample_count,
gdouble **sample_array
)
{
gboolean result;
gdouble *samples;
gint n_samples;
GimpGradient *gradient;
g_debug ("%s", G_STRFUNC);
/* Self's gradient is property "resource"
* (resource field of super is private.)
*/
g_object_get (self, "resource", &gradient, NULL);
g_return_val_if_fail (GIMP_IS_GRADIENT (gradient), FALSE);
result = gimp_gradient_get_uniform_samples (
gradient,
allocation_width,
FALSE, /* not reversed. */
&n_samples,
&samples);
if (result)
{
/* Return array of samples to dereferenced handles. */
*sample_array = samples;
*sample_count = n_samples;
}
/* When result is true, caller must free the array. */
return result;
}
/* Called on widget resized. */
static void
gimp_gradient_select_preview_size_allocate (GtkWidget *widget,
GtkAllocation *allocation,
GimpGradientSelectButton *self)
{
g_debug ("%s", G_STRFUNC);
/* Do nothing.
*
* In former code, we cached the gradient data in self, on allocate event.
* But allocate event always seems to be paired with a draw event,
* so there is no point in caching the gradient data.
* And caching gradient data is a premature optimization,
* without deep knowledge of Gtk and actual performance testing,
* you can't know caching helps performance.
*/
}
/* Draw array of samples.
* This understands mostly cairo, and little about gradient.
*/
static void
gimp_gradient_select_preview_draw (
cairo_t *cr,
gint src_width,
gint dest_width,
gdouble *src)
{
cairo_pattern_t *pattern;
cairo_surface_t *surface;
guchar *dest;
gint x;
pattern = gimp_cairo_checkerboard_create (cr, GIMP_CHECK_SIZE_SM, NULL, NULL);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_paint (cr);
surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, src_width, 1);
for (x = 0, dest = cairo_image_surface_get_data (surface);
x < src_width;
x++, src += 4, dest += 4)
{
GimpRGB color;
guchar r, g, b, a;
gimp_rgba_set (&color, src[0], src[1], src[2], src[3]);
gimp_rgba_get_uchar (&color, &r, &g, &b, &a);
GIMP_CAIRO_ARGB32_SET_PIXEL (dest, r, g, b, a);
}
cairo_surface_mark_dirty (surface);
pattern = cairo_pattern_create_for_surface (surface);
cairo_pattern_set_extend (pattern, CAIRO_EXTEND_REFLECT);
cairo_surface_destroy (surface);
cairo_scale (cr, (gdouble) dest_width / (gdouble) src_width, 1.0);
cairo_set_source (cr, pattern);
cairo_pattern_destroy (pattern);
cairo_paint (cr);
}
/* Handles a draw signal.
* Draw self, i.e. interior of button.
*
* Always returns FALSE, but doesn't draw when fail to get gradient data.
*
* Is passed neither gradient nor attributes of gradient: get them now from self.
*/
static gboolean
gimp_gradient_select_preview_draw_handler (
GtkWidget *widget,
cairo_t *cr,
GimpGradientSelectButton *self)
{
GtkAllocation allocation;
/* Attributes of the source.*/
gdouble *src;
gint n_samples;
gint src_width;
g_debug ("%s", G_STRFUNC);
gtk_widget_get_allocation (widget, &allocation);
if (!get_gradient_data (self, allocation.width, &n_samples, &src))
return FALSE;
/* Width in pixels of src, since BPP is 4. */
src_width = n_samples / 4;
gimp_gradient_select_preview_draw (cr, src_width, allocation.width, src);
g_free (src);
return FALSE;
}
static void
gimp_gradient_select_button_embed_interior (GimpGradientSelectButton *self)
{
GtkWidget *button;
GtkWidget *preview;
g_debug ("%s", G_STRFUNC);
/* Outermost is button. */
button = gtk_button_new ();
/* Entire interior of button is a preview image. */
preview = gtk_drawing_area_new ();
gtk_widget_set_size_request (preview, CELL_WIDTH, CELL_HEIGHT);
gtk_container_add (GTK_CONTAINER (button), preview);
g_signal_connect (preview, "size-allocate",
G_CALLBACK (gimp_gradient_select_preview_size_allocate),
self);
g_signal_connect (preview, "draw",
G_CALLBACK (gimp_gradient_select_preview_draw_handler),
self);
gtk_widget_show_all (button);
/* Remember widgets needed later. */
self->drag_region_widget = preview;
self->button = button;
self->preview = preview;
/* Call super with upcasts. */
gimp_resource_select_button_embed_interior (GIMP_RESOURCE_SELECT_BUTTON (self), button);
}
static void
gimp_gradient_select_button_set_drag_target (GimpGradientSelectButton *self)
{
/* Self knows the GtkTargetEntry, super knows how to create target and receive drag. */
gimp_resource_select_button_set_drag_target (GIMP_RESOURCE_SELECT_BUTTON (self),
self->drag_region_widget,
&drag_target);
}