GTK+ Reference Manual | ||||
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#include <gtk/gtk.h> GtkPreview; GtkPreviewInfo; union GtkDitherInfo; void gtk_preview_uninit (void); GtkWidget* gtk_preview_new (GtkPreviewType type); void gtk_preview_size (GtkPreview *preview, gint width, gint height); void gtk_preview_put (GtkPreview *preview, GdkWindow *window, GdkGC *gc, gint srcx, gint srcy, gint destx, gint desty, gint width, gint height); void gtk_preview_draw_row (GtkPreview *preview, guchar *data, gint x, gint y, gint w); void gtk_preview_set_expand (GtkPreview *preview, gboolean expand); void gtk_preview_set_gamma (double gamma_); void gtk_preview_set_color_cube (guint nred_shades, guint ngreen_shades, guint nblue_shades, guint ngray_shades); void gtk_preview_set_install_cmap (gint install_cmap); void gtk_preview_set_reserved (gint nreserved); void gtk_preview_set_dither (GtkPreview *preview, GdkRgbDither dither); GdkVisual* gtk_preview_get_visual (void); GdkColormap* gtk_preview_get_cmap (void); GtkPreviewInfo* gtk_preview_get_info (void); void gtk_preview_reset (void);
The GtkPreview widget provides a simple interface used to display images as RGB or grayscale data. It's deprecated; just use a GdkPixbuf displayed by a GtkImage, or perhaps a GtkDrawingArea. GtkPreview has no advantage over those approaches.
typedef struct _GtkPreview GtkPreview;
GtkPreview
is deprecated and should not be used in newly-written code.
The GtkPreview struct contains private data only, and should be accessed using the functions below.
typedef struct { guchar *lookup; gdouble gamma; } GtkPreviewInfo;
GtkPreviewInfo
is deprecated and should not be used in newly-written code.
Contains information about global properties of preview widgets. The GtkPreviewInfo struct contains the following fields. (These fields should be considered read-only. They should never be set by an application.)
GdkVisual *visual; | the visual used by all previews. |
GdkColormap *cmap; | the colormap used by all previews. |
gdouble gamma; | the gamma correction value used by all previews (See gtk_preview_set_gamma() ). |
union GtkDitherInfo { gushort s[2]; guchar c[4]; };
GtkDitherInfo
is deprecated and should not be used in newly-written code.
This union not used in GTK+.
void gtk_preview_uninit (void);
gtk_preview_uninit
is deprecated and should not be used in newly-written code.
This function is deprecated and does nothing.
GtkWidget* gtk_preview_new (GtkPreviewType type);
gtk_preview_new
is deprecated and should not be used in newly-written code.
Create a new preview widget.
type : |
the type data contained by the widget. (Grayscale or RGB) |
Returns : | a new GtkPreview |
void gtk_preview_size (GtkPreview *preview, gint width, gint height);
gtk_preview_size
is deprecated and should not be used in newly-written code.
Set the size that the preview widget will request
in response to a "size_request" signal. The
drawing area may actually be allocated a size
larger than this depending on how it is packed
within the enclosing containers. The effect
of this is determined by whether the preview
is set to expand or not (see gtk_preview_expand()
)
preview : |
a GtkPreview. |
width : |
the new width. |
height : |
the new height. |
void gtk_preview_put (GtkPreview *preview, GdkWindow *window, GdkGC *gc, gint srcx, gint srcy, gint destx, gint desty, gint width, gint height);
gtk_preview_put
is deprecated and should not be used in newly-written code.
Takes a portion of the contents of a preview widget
and draws it onto the given drawable, window
.
preview : |
a GtkPreview. |
window : |
a window or pixmap. |
gc : |
The graphics context for the operation. Only the clip mask for this GC matters. |
srcx : |
the x coordinate of the upper left corner in the source image. |
srcy : |
the y coordinate of the upper left corner in the source image. |
destx : |
the x coordinate of the upper left corner in the destination image. |
desty : |
the y coordinate of the upper left corner in the destination image. |
width : |
the width of the rectangular portion to draw. |
height : |
the height of the rectangular portion to draw. |
void gtk_preview_draw_row (GtkPreview *preview, guchar *data, gint x, gint y, gint w);
gtk_preview_draw_row
is deprecated and should not be used in newly-written code.
Sets the data for a portion of a row.
preview : |
a GtkPreview. |
data : |
the new data for the portion. It should contain
w bytes of data if the preview is of type
GTK_TYPE_GRAYSCALE, and 3*w bytes of data
if the preview is of type GTK_TYPE_COLOR.
|
x : |
the starting value on the row to set. |
y : |
the row to change. |
w : |
the number of pixels in the row to change. |
void gtk_preview_set_expand (GtkPreview *preview, gboolean expand);
gtk_preview_set_expand
is deprecated and should not be used in newly-written code.
Determines the way that the the preview widget behaves
when the size it is allocated is larger than the requested
size. If expand
is FALSE
, then the preview's window
and buffer will be no larger than the size set with
gtk_preview_size()
, and the data set will be centered
in the allocation if it is larger. If expand
is TRUE
then the window and buffer will expand with the allocation;
the application is responsible for catching
the "size_allocate" signal and providing the data
appropriate for this size.
preview : |
a GtkPreview. |
expand : |
whether the preview's window should expand or not. |
void gtk_preview_set_gamma (double gamma_);
gtk_preview_set_gamma
is deprecated and should not be used in newly-written code.
Set the gamma-correction value for all preview widgets.
(This function will eventually be replaced with a
function that sets a per-preview-widget gamma value).
The resulting intensity is given by:
destination_value * pow (source_value/255, 1/gamma)
.
The gamma value is applied when the data is
set with gtk_preview_draw_row()
so changing this
value will not affect existing data in preview
widgets.
gamma_ : |
the new gamma value. |
void gtk_preview_set_color_cube (guint nred_shades, guint ngreen_shades, guint nblue_shades, guint ngray_shades);
gtk_preview_set_color_cube
is deprecated and should not be used in newly-written code.
This function is deprecated and does nothing. GdkRGB automatically picks an optimium color cube for the display.
nred_shades : |
ignored |
ngreen_shades : |
ignored |
nblue_shades : |
ignored |
ngray_shades : |
ignored |
void gtk_preview_set_install_cmap (gint install_cmap);
gtk_preview_set_install_cmap
is deprecated and should not be used in newly-written code.
This function is deprecated and does nothing. GdkRGB will automatically pick a private colormap if it cannot allocate sufficient colors.
install_cmap : |
ignored. |
void gtk_preview_set_reserved (gint nreserved);
gtk_preview_set_reserved
is deprecated and should not be used in newly-written code.
This function is deprecated and does nothing.
nreserved : |
ignored. |
void gtk_preview_set_dither (GtkPreview *preview, GdkRgbDither dither);
gtk_preview_set_dither
is deprecated and should not be used in newly-written code.
Set the dithering mode for the display.
preview : |
a GtkPreview. |
dither : |
the dithering mode. |
GdkVisual* gtk_preview_get_visual (void);
gtk_preview_get_visual
is deprecated and should not be used in newly-written code.
Returns the visual used by preview widgets. This
function is deprecated, and you should use
gdk_rgb_get_visual()
instead.
Returns : | the visual for previews. |
GdkColormap* gtk_preview_get_cmap (void);
gtk_preview_get_cmap
is deprecated and should not be used in newly-written code.
Returns the colormap used by preview widgets. This
function is deprecated, and you should use
gdk_rgb_get_cmap()
instead.
Returns : | the colormap for previews. |
GtkPreviewInfo* gtk_preview_get_info (void);
gtk_preview_get_info
is deprecated and should not be used in newly-written code.
Return a GtkPreviewInfo structure containing global information about preview widgets.
Returns : | a GtkPreviewInfo structure. The return value belongs to GTK+ and must not be modified or freed. |
"expand"
property"expand" gboolean : Read / Write
Whether the preview widget should take up the entire space it is allocated.
Default value: FALSE