| /* |
| * Copyright © 2018 Benjamin Otte |
| * |
| * 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 2.1 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 <http://www.gnu.org/licenses/>. |
| * |
| * Authors: Benjamin Otte <otte@gnome.org> |
| */ |
| |
| #ifndef __GDK_PAINTABLE_H__ |
| #define __GDK_PAINTABLE_H__ |
| |
| #if !defined (__GDK_H_INSIDE__) && !defined (GTK_COMPILATION) |
| #error "Only <gdk/gdk.h> can be included directly." |
| #endif |
| |
| #include <gdk/gdktypes.h> |
| #include <gdk/gdkversionmacros.h> |
| |
| G_BEGIN_DECLS |
| |
| #define GDK_TYPE_PAINTABLE (gdk_paintable_get_type ()) |
| |
| GDK_AVAILABLE_IN_ALL |
| G_DECLARE_INTERFACE (GdkPaintable, gdk_paintable, GDK, PAINTABLE, GObject) |
| |
| /** |
| * GdkPaintableFlags: |
| * @GDK_PAINTABLE_STATIC_SIZE: The size is immutable. |
| * The #GdkPaintable::invalidate-size signal will never be |
| * emitted. |
| * @GDK_PAINTABLE_STATIC_CONTENTS: The content is immutable. |
| * The #GdkPaintable::invalidate-contents signal will never be |
| * emitted. |
| * |
| * Flags about this object. Implementations use these for optimizations |
| * such as caching. |
| */ |
| typedef enum { |
| GDK_PAINTABLE_STATIC_SIZE = 1 << 0, |
| GDK_PAINTABLE_STATIC_CONTENTS = 1 << 1 |
| } GdkPaintableFlags; |
| |
| /** |
| * GdkPaintableInterface: |
| * @snapshot: Snapshot the paintable. The given @width and @height are |
| * guaranteed to be larger than 0.0. The resulting snapshot must modify |
| * only the area in the rectangle from (0,0) to (width, height). |
| * This is the only function that must be implemented for this interface. |
| * @get_current_image: return a #GdkPaintable that does not change over |
| * time. This means the GDK_PAINTABLE_STATIC_SIZE and |
| * %GDK_PAINTABLE_STATIC_CONTENTS flag are set. |
| * @get_flags: Get the flags for this instance. See #GdkPaintableFlags |
| * for details. |
| * @get_intrinsic_width: The preferred width for this object to be |
| * snapshot at or 0 if none. This is purely a hint. The object must still |
| * be able to render at any size. |
| * @get_intrinsic_height: The preferred height for this object to be |
| * snapshot at or 0 if none. This is purely a hint. The object must still |
| * be able to render at any size. |
| * @get_intrinsic_aspect_ratio: The preferred aspect ratio for this object |
| * or 0 if none. If both #GdkPaintableInterface.get_intrinsic_width() and |
| * #GdkPaintableInterface.get_intrinsic_height() return non-zero values, |
| * this function should return the aspect ratio computed from those. |
| * |
| * The list of functions that can be implemented for the #GdkPaintable interface. |
| * Note that apart from the first function, no function is mandatory to implement, |
| * though it is a good idea to implement #GdkPaintableInterface.get_current_image() |
| * for non-static paintables and #GdkPaintableInterface.get_flags() if the image |
| * is not dynamic as the default implementation returns no flags and that will |
| * make the implementation likely quite slow. |
| */ |
| struct _GdkPaintableInterface |
| { |
| /*< private >*/ |
| GTypeInterface g_iface; |
| |
| /*< public >*/ |
| /* draw to 0,0 with the given width and height */ |
| void (* snapshot) (GdkPaintable *paintable, |
| GdkSnapshot *snapshot, |
| double width, |
| double height); |
| /* get the current contents in an immutable form (optional) */ |
| GdkPaintable * (* get_current_image) (GdkPaintable *paintable); |
| |
| /* get flags for potential optimizations (optional) */ |
| GdkPaintableFlags (* get_flags) (GdkPaintable *paintable); |
| /* preferred width of paintable or 0 if it has no width (optional) */ |
| int (* get_intrinsic_width) (GdkPaintable *paintable); |
| /* preferred height of paintable or 0 if it has no height (optional) */ |
| int (* get_intrinsic_height) (GdkPaintable *paintable); |
| /* aspect ratio (width / height) of paintable or 0 if it has no aspect ratio (optional) */ |
| double (* get_intrinsic_aspect_ratio) (GdkPaintable *paintable); |
| }; |
| |
| GDK_AVAILABLE_IN_ALL |
| void gdk_paintable_snapshot (GdkPaintable *paintable, |
| GdkSnapshot *snapshot, |
| double width, |
| double height); |
| GDK_AVAILABLE_IN_ALL |
| GdkPaintable * gdk_paintable_get_current_image (GdkPaintable *paintable); |
| |
| GDK_AVAILABLE_IN_ALL |
| GdkPaintableFlags |
| gdk_paintable_get_flags (GdkPaintable *paintable); |
| GDK_AVAILABLE_IN_ALL |
| int gdk_paintable_get_intrinsic_width (GdkPaintable *paintable); |
| GDK_AVAILABLE_IN_ALL |
| int gdk_paintable_get_intrinsic_height (GdkPaintable *paintable); |
| GDK_AVAILABLE_IN_ALL |
| double gdk_paintable_get_intrinsic_aspect_ratio(GdkPaintable *paintable); |
| |
| GDK_AVAILABLE_IN_ALL |
| void gdk_paintable_compute_concrete_size (GdkPaintable *paintable, |
| double specified_width, |
| double specified_height, |
| double default_width, |
| double default_height, |
| double *concrete_width, |
| double *concrete_height); |
| /* for implementations only */ |
| GDK_AVAILABLE_IN_ALL |
| void gdk_paintable_invalidate_contents (GdkPaintable *paintable); |
| GDK_AVAILABLE_IN_ALL |
| void gdk_paintable_invalidate_size (GdkPaintable *paintable); |
| GDK_AVAILABLE_IN_ALL |
| GdkPaintable * gdk_paintable_new_empty (int intrinsic_width, |
| int intrinsic_height); |
| |
| |
| G_END_DECLS |
| |
| #endif /* __GDK_PAINTABLE_H__ */ |
