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eom-scroll-view.c
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eom-scroll-view.c
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#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdlib.h>
#include <math.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
#include <gdk/gdkkeysyms.h>
#ifdef HAVE_RSVG
#include <librsvg/rsvg.h>
#endif
#include "eom-config-keys.h"
#include "eom-enum-types.h"
#include "eom-marshal.h"
#include "eom-scroll-view.h"
#include "eom-debug.h"
#include "zoom.h"
#include <gdk/gdk.h>
/* Maximum size of delayed repaint rectangles */
#define PAINT_RECT_WIDTH 128
#define PAINT_RECT_HEIGHT 128
/* Scroll step increment */
#define SCROLL_STEP_SIZE 32
/* Maximum zoom factor */
#define MAX_ZOOM_FACTOR 20
#define MIN_ZOOM_FACTOR 0.02
#define CHECK_MEDIUM 8
#define CHECK_BLACK "#000000"
#define CHECK_DARK "#555555"
#define CHECK_GRAY "#808080"
#define CHECK_LIGHT "#cccccc"
#define CHECK_WHITE "#ffffff"
/* Default increment for zooming. The current zoom factor is multiplied or
* divided by this amount on every zooming step. For consistency, you should
* use the same value elsewhere in the program.
*/
#define IMAGE_VIEW_ZOOM_MULTIPLIER 1.05
/* States for automatically adjusting the zoom factor */
typedef enum {
ZOOM_MODE_FIT, /* Image is fitted to scroll view even if the latter changes size */
ZOOM_MODE_FREE /* The image remains at its current zoom factor even if the scrollview changes size */
} ZoomMode;
/* Signal IDs */
enum {
SIGNAL_ZOOM_CHANGED,
SIGNAL_LAST
};
static guint view_signals [SIGNAL_LAST] = { 0 };
typedef enum {
EOM_SCROLL_VIEW_CURSOR_NORMAL,
EOM_SCROLL_VIEW_CURSOR_HIDDEN,
EOM_SCROLL_VIEW_CURSOR_DRAG
} EomScrollViewCursor;
/* Drag 'n Drop */
static GtkTargetEntry target_table[] = {
{ "text/uri-list", 0, 0},
};
enum {
PROP_0,
PROP_ANTIALIAS_IN,
PROP_ANTIALIAS_OUT,
PROP_BACKGROUND_COLOR,
PROP_SCROLLWHEEL_ZOOM,
PROP_TRANSP_COLOR,
PROP_TRANSPARENCY_STYLE,
PROP_USE_BG_COLOR,
PROP_ZOOM_MULTIPLIER
};
/* Private part of the EomScrollView structure */
struct _EomScrollViewPrivate {
/* some widgets we rely on */
GtkWidget *display;
GtkAdjustment *hadj;
GtkAdjustment *vadj;
GtkWidget *hbar;
GtkWidget *vbar;
GtkWidget *menu;
/* actual image */
EomImage *image;
guint image_changed_id;
guint frame_changed_id;
GdkPixbuf *pixbuf;
cairo_surface_t *surface;
/* scale factor */
gint scale;
/* zoom mode, either ZOOM_MODE_FIT or ZOOM_MODE_FREE */
ZoomMode zoom_mode;
/* whether to allow zoom > 1.0 on zoom fit */
gboolean upscale;
/* the actual zoom factor */
double zoom;
/* the minimum possible (reasonable) zoom factor */
double min_zoom;
/* Current scrolling offsets */
int xofs, yofs;
/* handler ID for paint idle callback */
guint idle_id;
/* Interpolation type when zoomed in*/
cairo_filter_t interp_type_in;
/* Interpolation type when zoomed out*/
cairo_filter_t interp_type_out;
/* Scroll wheel zoom */
gboolean scroll_wheel_zoom;
/* Scroll wheel zoom */
gdouble zoom_multiplier;
/* dragging stuff */
int drag_anchor_x, drag_anchor_y;
int drag_ofs_x, drag_ofs_y;
guint dragging : 1;
/* how to indicate transparency in images */
EomTransparencyStyle transp_style;
GdkRGBA transp_color;
/* the type of the cursor we are currently showing */
EomScrollViewCursor cursor;
gboolean use_bg_color;
GdkRGBA *background_color;
GdkRGBA *override_bg_color;
cairo_surface_t *background_surface;
};
static void scroll_by (EomScrollView *view, int xofs, int yofs);
static void set_zoom_fit (EomScrollView *view);
/* static void request_paint_area (EomScrollView *view, GdkRectangle *area); */
static void set_minimum_zoom_factor (EomScrollView *view);
static void view_on_drag_begin_cb (GtkWidget *widget, GdkDragContext *context,
gpointer user_data);
static void view_on_drag_data_get_cb (GtkWidget *widget,
GdkDragContext*drag_context,
GtkSelectionData *data, guint info,
guint time, gpointer user_data);
#define EOM_SCROLL_VIEW_GET_PRIVATE(object) \
(G_TYPE_INSTANCE_GET_PRIVATE ((object), EOM_TYPE_SCROLL_VIEW, EomScrollViewPrivate))
static gboolean _eom_gdk_rgba_equal0 (const GdkRGBA *a, const GdkRGBA *b);
G_DEFINE_TYPE (EomScrollView, eom_scroll_view, GTK_TYPE_GRID)
/*===================================
widget size changing handler &
util functions
---------------------------------*/
static cairo_surface_t *
create_surface_from_pixbuf (EomScrollView *view, GdkPixbuf *pixbuf)
{
cairo_surface_t *surface;
surface = gdk_cairo_surface_create_from_pixbuf (pixbuf,
view->priv->scale,
gtk_widget_get_window (view->priv->display));
return surface;
}
/* Disconnects from the EomImage and removes references to it */
static void
free_image_resources (EomScrollView *view)
{
EomScrollViewPrivate *priv;
priv = view->priv;
if (priv->image_changed_id > 0) {
g_signal_handler_disconnect (G_OBJECT (priv->image), priv->image_changed_id);
priv->image_changed_id = 0;
}
if (priv->frame_changed_id > 0) {
g_signal_handler_disconnect (G_OBJECT (priv->image), priv->frame_changed_id);
priv->frame_changed_id = 0;
}
if (priv->image != NULL) {
eom_image_data_unref (priv->image);
priv->image = NULL;
}
if (priv->pixbuf != NULL) {
g_object_unref (priv->pixbuf);
priv->pixbuf = NULL;
}
if (priv->surface !=NULL) {
cairo_surface_destroy (priv->surface);
priv->surface = NULL;
}
}
/* Computes the size in pixels of the scaled image */
static void
compute_scaled_size (EomScrollView *view, double zoom, int *width, int *height)
{
EomScrollViewPrivate *priv;
priv = view->priv;
if (priv->pixbuf) {
*width = floor (gdk_pixbuf_get_width (priv->pixbuf) / priv->scale * zoom + 0.5);
*height = floor (gdk_pixbuf_get_height (priv->pixbuf) / priv->scale * zoom + 0.5);
} else
*width = *height = 0;
}
/* Computes the offsets for the new zoom value so that they keep the image
* centered on the view.
*/
static void
compute_center_zoom_offsets (EomScrollView *view,
double old_zoom, double new_zoom,
int width, int height,
double zoom_x_anchor, double zoom_y_anchor,
int *xofs, int *yofs)
{
EomScrollViewPrivate *priv;
int old_scaled_width, old_scaled_height;
int new_scaled_width, new_scaled_height;
double view_cx, view_cy;
priv = view->priv;
compute_scaled_size (view, old_zoom,
&old_scaled_width, &old_scaled_height);
if (old_scaled_width < width)
view_cx = (zoom_x_anchor * old_scaled_width) / old_zoom;
else
view_cx = (priv->xofs + zoom_x_anchor * width) / old_zoom;
if (old_scaled_height < height)
view_cy = (zoom_y_anchor * old_scaled_height) / old_zoom;
else
view_cy = (priv->yofs + zoom_y_anchor * height) / old_zoom;
compute_scaled_size (view, new_zoom,
&new_scaled_width, &new_scaled_height);
if (new_scaled_width < width)
*xofs = 0;
else {
*xofs = floor (view_cx * new_zoom - zoom_x_anchor * width + 0.5);
if (*xofs < 0)
*xofs = 0;
}
if (new_scaled_height < height)
*yofs = 0;
else {
*yofs = floor (view_cy * new_zoom - zoom_y_anchor * height + 0.5);
if (*yofs < 0)
*yofs = 0;
}
}
/* Sets the scrollbar values based on the current scrolling offset */
static void
update_scrollbar_values (EomScrollView *view)
{
EomScrollViewPrivate *priv;
int scaled_width, scaled_height;
gdouble page_size,page_increment,step_increment;
gdouble lower, upper;
GtkAllocation allocation;
priv = view->priv;
if (!gtk_widget_get_visible (GTK_WIDGET (priv->hbar))
&& !gtk_widget_get_visible (GTK_WIDGET (priv->vbar)))
return;
compute_scaled_size (view, priv->zoom, &scaled_width, &scaled_height);
gtk_widget_get_allocation (GTK_WIDGET (priv->display), &allocation);
if (gtk_widget_get_visible (GTK_WIDGET (priv->hbar))) {
/* Set scroll increments */
page_size = MIN (scaled_width, allocation.width);
page_increment = allocation.width / 2;
step_increment = SCROLL_STEP_SIZE;
/* Set scroll bounds and new offsets */
lower = 0;
upper = scaled_width;
priv->xofs = CLAMP (priv->xofs, 0, upper - page_size);
g_signal_handlers_block_matched (
priv->hadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
gtk_adjustment_configure (priv->hadj, priv->xofs, lower,
upper, step_increment,
page_increment, page_size);
g_signal_handlers_unblock_matched (
priv->hadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
}
if (gtk_widget_get_visible (GTK_WIDGET (priv->vbar))) {
page_size = MIN (scaled_height, allocation.height);
page_increment = allocation.height / 2;
step_increment = SCROLL_STEP_SIZE;
lower = 0;
upper = scaled_height;
priv->yofs = CLAMP (priv->yofs, 0, upper - page_size);
g_signal_handlers_block_matched (
priv->vadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
gtk_adjustment_configure (priv->vadj, priv->yofs, lower,
upper, step_increment,
page_increment, page_size);
g_signal_handlers_unblock_matched (
priv->vadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
}
}
static void
eom_scroll_view_set_cursor (EomScrollView *view, EomScrollViewCursor new_cursor)
{
GdkCursor *cursor = NULL;
GdkDisplay *display;
GtkWidget *widget;
if (view->priv->cursor == new_cursor) {
return;
}
widget = gtk_widget_get_toplevel (GTK_WIDGET (view));
display = gtk_widget_get_display (widget);
view->priv->cursor = new_cursor;
switch (new_cursor) {
case EOM_SCROLL_VIEW_CURSOR_NORMAL:
gdk_window_set_cursor (gtk_widget_get_window (widget), NULL);
break;
case EOM_SCROLL_VIEW_CURSOR_HIDDEN:
cursor = gdk_cursor_new_for_display (display, GDK_BLANK_CURSOR);
break;
case EOM_SCROLL_VIEW_CURSOR_DRAG:
cursor = gdk_cursor_new_for_display (display, GDK_FLEUR);
break;
}
if (cursor) {
gdk_window_set_cursor (gtk_widget_get_window (widget), cursor);
g_object_unref (cursor);
gdk_flush();
}
}
/* Changes visibility of the scrollbars based on the zoom factor and the
* specified allocation, or the current allocation if NULL is specified.
*/
static void
check_scrollbar_visibility (EomScrollView *view, GtkAllocation *alloc)
{
EomScrollViewPrivate *priv;
int bar_height;
int bar_width;
int img_width;
int img_height;
GtkRequisition req;
int width, height;
gboolean hbar_visible, vbar_visible;
priv = view->priv;
if (alloc) {
width = alloc->width;
height = alloc->height;
} else {
GtkAllocation allocation;
gtk_widget_get_allocation (GTK_WIDGET (view), &allocation);
width = allocation.width;
height = allocation.height;
}
compute_scaled_size (view, priv->zoom, &img_width, &img_height);
/* this should work fairly well in this special case for scrollbars */
gtk_widget_get_preferred_size (priv->hbar, &req, NULL);
bar_height = req.height;
gtk_widget_get_preferred_size (priv->vbar, &req, NULL);
bar_width = req.width;
eom_debug_message (DEBUG_WINDOW, "Widget Size allocate: %i, %i Bar: %i, %i\n",
width, height, bar_width, bar_height);
hbar_visible = vbar_visible = FALSE;
if (priv->zoom_mode == ZOOM_MODE_FIT)
hbar_visible = vbar_visible = FALSE;
else if (img_width <= width && img_height <= height)
hbar_visible = vbar_visible = FALSE;
else if (img_width > width && img_height > height)
hbar_visible = vbar_visible = TRUE;
else if (img_width > width) {
hbar_visible = TRUE;
if (img_height <= (height - bar_height))
vbar_visible = FALSE;
else
vbar_visible = TRUE;
}
else if (img_height > height) {
vbar_visible = TRUE;
if (img_width <= (width - bar_width))
hbar_visible = FALSE;
else
hbar_visible = TRUE;
}
if (hbar_visible != gtk_widget_get_visible (GTK_WIDGET (priv->hbar)))
g_object_set (G_OBJECT (priv->hbar), "visible", hbar_visible, NULL);
if (vbar_visible != gtk_widget_get_visible (GTK_WIDGET (priv->vbar)))
g_object_set (G_OBJECT (priv->vbar), "visible", vbar_visible, NULL);
}
#define DOUBLE_EQUAL_MAX_DIFF 1e-6
#define DOUBLE_EQUAL(a,b) (fabs (a - b) < DOUBLE_EQUAL_MAX_DIFF)
/* Returns whether the image is zoomed in */
static gboolean
is_zoomed_in (EomScrollView *view)
{
EomScrollViewPrivate *priv;
priv = view->priv;
return priv->zoom - 1.0 > DOUBLE_EQUAL_MAX_DIFF;
}
/* Returns whether the image is zoomed out */
static gboolean
is_zoomed_out (EomScrollView *view)
{
EomScrollViewPrivate *priv;
priv = view->priv;
return DOUBLE_EQUAL_MAX_DIFF + priv->zoom - 1.0 < 0.0;
}
/* Returns wether the image is movable, that means if it is larger then
* the actual visible area.
*/
static gboolean
is_image_movable (EomScrollView *view)
{
EomScrollViewPrivate *priv;
priv = view->priv;
return (gtk_widget_get_visible (priv->hbar) || gtk_widget_get_visible (priv->vbar));
}
/*===================================
drawing core
---------------------------------*/
static void
get_transparency_params (EomScrollView *view, int *size, GdkRGBA *color1, GdkRGBA *color2)
{
EomScrollViewPrivate *priv;
priv = view->priv;
/* Compute transparency parameters */
switch (priv->transp_style) {
case EOM_TRANSP_BACKGROUND: {
/* Simply return fully transparent color */
color1->red = color1->green = color1->blue = color1->alpha = 0.0;
color2->red = color2->green = color2->blue = color2->alpha = 0.0;
break;
}
case EOM_TRANSP_CHECKED:
g_warn_if_fail (gdk_rgba_parse (color1, CHECK_GRAY));
g_warn_if_fail (gdk_rgba_parse (color2, CHECK_LIGHT));
break;
case EOM_TRANSP_COLOR:
*color1 = *color2 = priv->transp_color;
break;
default:
g_assert_not_reached ();
};
*size = CHECK_MEDIUM;
}
static cairo_surface_t *
create_background_surface (EomScrollView *view)
{
int check_size;
GdkRGBA check_1;
GdkRGBA check_2;
cairo_surface_t *surface;
get_transparency_params (view, &check_size, &check_1, &check_2);
surface = gdk_window_create_similar_surface (gtk_widget_get_window (view->priv->display),
CAIRO_CONTENT_COLOR_ALPHA,
check_size * 2, check_size * 2);
cairo_t* cr = cairo_create (surface);
/* Use source operator to make fully transparent work */
cairo_set_operator (cr, CAIRO_OPERATOR_SOURCE);
gdk_cairo_set_source_rgba(cr, &check_1);
cairo_rectangle (cr, 0, 0, check_size, check_size);
cairo_rectangle (cr, check_size, check_size, check_size, check_size);
cairo_fill (cr);
gdk_cairo_set_source_rgba(cr, &check_2);
cairo_rectangle (cr, 0, check_size, check_size, check_size);
cairo_rectangle (cr, check_size, 0, check_size, check_size);
cairo_fill (cr);
cairo_destroy (cr);
return surface;
}
/* =======================================
scrolling stuff
--------------------------------------*/
/* Scrolls the view to the specified offsets. */
static void
scroll_to (EomScrollView *view, int x, int y, gboolean change_adjustments)
{
EomScrollViewPrivate *priv;
GtkAllocation allocation;
int xofs, yofs;
GdkWindow *window;
priv = view->priv;
/* Check bounds & Compute offsets */
if (gtk_widget_get_visible (priv->hbar)) {
x = CLAMP (x, 0, gtk_adjustment_get_upper (priv->hadj)
- gtk_adjustment_get_page_size (priv->hadj));
xofs = x - priv->xofs;
} else
xofs = 0;
if (gtk_widget_get_visible (priv->vbar)) {
y = CLAMP (y, 0, gtk_adjustment_get_upper (priv->vadj)
- gtk_adjustment_get_page_size (priv->vadj));
yofs = y - priv->yofs;
} else
yofs = 0;
if (xofs == 0 && yofs == 0)
return;
priv->xofs = x;
priv->yofs = y;
if (!gtk_widget_is_drawable (priv->display))
goto out;
gtk_widget_get_allocation (GTK_WIDGET (priv->display), &allocation);
if (abs (xofs) >= allocation.width || abs (yofs) >= allocation.height) {
gtk_widget_queue_draw (GTK_WIDGET (priv->display));
goto out;
}
window = gtk_widget_get_window (GTK_WIDGET (priv->display));
/* Scroll the window area and process exposure synchronously. */
gdk_window_scroll (window, -xofs, -yofs);
gdk_window_process_updates (window, TRUE);
out:
if (!change_adjustments)
return;
g_signal_handlers_block_matched (
priv->hadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
g_signal_handlers_block_matched (
priv->vadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
gtk_adjustment_set_value (priv->hadj, x);
gtk_adjustment_set_value (priv->vadj, y);
g_signal_handlers_unblock_matched (
priv->hadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
g_signal_handlers_unblock_matched (
priv->vadj, G_SIGNAL_MATCH_DATA,
0, 0, NULL, NULL, view);
}
/* Scrolls the image view by the specified offsets. Notifies the adjustments
* about their new values.
*/
static void
scroll_by (EomScrollView *view, int xofs, int yofs)
{
EomScrollViewPrivate *priv;
priv = view->priv;
scroll_to (view, priv->xofs + xofs, priv->yofs + yofs, TRUE);
}
/* Callback used when an adjustment is changed */
static void
adjustment_changed_cb (GtkAdjustment *adj, gpointer data)
{
EomScrollView *view;
EomScrollViewPrivate *priv;
view = EOM_SCROLL_VIEW (data);
priv = view->priv;
scroll_to (view, gtk_adjustment_get_value (priv->hadj),
gtk_adjustment_get_value (priv->vadj), FALSE);
}
/* Drags the image to the specified position */
static void
drag_to (EomScrollView *view, int x, int y)
{
EomScrollViewPrivate *priv;
int dx, dy;
priv = view->priv;
dx = priv->drag_anchor_x - x;
dy = priv->drag_anchor_y - y;
x = priv->drag_ofs_x + dx;
y = priv->drag_ofs_y + dy;
scroll_to (view, x, y, TRUE);
}
static void
set_minimum_zoom_factor (EomScrollView *view)
{
g_return_if_fail (EOM_IS_SCROLL_VIEW (view));
view->priv->min_zoom = MAX (1.0 / gdk_pixbuf_get_width (view->priv->pixbuf) / view->priv->scale,
MAX(1.0 / gdk_pixbuf_get_height (view->priv->pixbuf) / view->priv->scale,
MIN_ZOOM_FACTOR) );
return;
}
/**
* set_zoom:
* @view: A scroll view.
* @zoom: Zoom factor.
* @have_anchor: Whether the anchor point specified by (@anchorx, @anchory)
* should be used.
* @anchorx: Horizontal anchor point in pixels.
* @anchory: Vertical anchor point in pixels.
*
* Sets the zoom factor for an image view. The anchor point can be used to
* specify the point that stays fixed when the image is zoomed. If @have_anchor
* is %TRUE, then (@anchorx, @anchory) specify the point relative to the image
* view widget's allocation that will stay fixed when zooming. If @have_anchor
* is %FALSE, then the center point of the image view will be used.
**/
static void
set_zoom (EomScrollView *view, double zoom,
gboolean have_anchor, int anchorx, int anchory)
{
EomScrollViewPrivate *priv;
GtkAllocation allocation;
int xofs, yofs;
double x_rel, y_rel;
priv = view->priv;
if (priv->pixbuf == NULL)
return;
if (zoom > MAX_ZOOM_FACTOR)
zoom = MAX_ZOOM_FACTOR;
else if (zoom < MIN_ZOOM_FACTOR)
zoom = MIN_ZOOM_FACTOR;
if (DOUBLE_EQUAL (priv->zoom, zoom))
return;
if (DOUBLE_EQUAL (priv->zoom, priv->min_zoom) && zoom < priv->zoom)
return;
priv->zoom_mode = ZOOM_MODE_FREE;
gtk_widget_get_allocation (GTK_WIDGET (priv->display), &allocation);
/* compute new xofs/yofs values */
if (have_anchor) {
x_rel = (double) anchorx / allocation.width;
y_rel = (double) anchory / allocation.height;
} else {
x_rel = 0.5;
y_rel = 0.5;
}
compute_center_zoom_offsets (view, priv->zoom, zoom,
allocation.width, allocation.height,
x_rel, y_rel,
&xofs, &yofs);
/* set new values */
priv->xofs = xofs; /* (img_width * x_rel * zoom) - anchorx; */
priv->yofs = yofs; /* (img_height * y_rel * zoom) - anchory; */
#if 0
g_print ("xofs: %i yofs: %i\n", priv->xofs, priv->yofs);
#endif
if (zoom <= priv->min_zoom)
priv->zoom = priv->min_zoom;
else
priv->zoom = zoom;
/* we make use of the new values here */
check_scrollbar_visibility (view, NULL);
update_scrollbar_values (view);
/* repaint the whole image */
gtk_widget_queue_draw (GTK_WIDGET (priv->display));
g_signal_emit (view, view_signals [SIGNAL_ZOOM_CHANGED], 0, priv->zoom);
}
/* Zooms the image to fit the available allocation */
static void
set_zoom_fit (EomScrollView *view)
{
EomScrollViewPrivate *priv;
GtkAllocation allocation;
double new_zoom;
priv = view->priv;
priv->zoom_mode = ZOOM_MODE_FIT;
if (!gtk_widget_get_mapped (GTK_WIDGET (view)))
return;
if (priv->pixbuf == NULL)
return;
gtk_widget_get_allocation (GTK_WIDGET(priv->display), &allocation);
new_zoom = zoom_fit_scale (allocation.width, allocation.height,
gdk_pixbuf_get_width (priv->pixbuf) / priv->scale,
gdk_pixbuf_get_height (priv->pixbuf) / priv->scale,
priv->upscale);
if (new_zoom > MAX_ZOOM_FACTOR)
new_zoom = MAX_ZOOM_FACTOR;
else if (new_zoom < MIN_ZOOM_FACTOR)
new_zoom = MIN_ZOOM_FACTOR;
priv->zoom = new_zoom;
priv->xofs = 0;
priv->yofs = 0;
g_signal_emit (view, view_signals [SIGNAL_ZOOM_CHANGED], 0, priv->zoom);
}
/*===================================
internal signal callbacks
---------------------------------*/
/* Key press event handler for the image view */
static gboolean
display_key_press_event (GtkWidget *widget, GdkEventKey *event, gpointer data)
{
EomScrollView *view;
EomScrollViewPrivate *priv;
GtkAllocation allocation;
gboolean do_zoom;
double zoom;
gboolean do_scroll;
int xofs, yofs;
view = EOM_SCROLL_VIEW (data);
priv = view->priv;
do_zoom = FALSE;
do_scroll = FALSE;
xofs = yofs = 0;
zoom = 1.0;
gtk_widget_get_allocation (GTK_WIDGET (priv->display), &allocation);
/* EomScrollView doesn't handle/have any Alt+Key combos */
if (event->state & GDK_MOD1_MASK) {
return FALSE;
}
switch (event->keyval) {
case GDK_KEY_Up:
do_scroll = TRUE;
xofs = 0;
yofs = -SCROLL_STEP_SIZE;
break;
case GDK_KEY_Page_Up:
do_scroll = TRUE;
if (event->state & GDK_CONTROL_MASK) {
xofs = -(allocation.width * 3) / 4;
yofs = 0;
} else {
xofs = 0;
yofs = -(allocation.height * 3) / 4;
}
break;
case GDK_KEY_Down:
do_scroll = TRUE;
xofs = 0;
yofs = SCROLL_STEP_SIZE;
break;
case GDK_KEY_Page_Down:
do_scroll = TRUE;
if (event->state & GDK_CONTROL_MASK) {
xofs = (allocation.width * 3) / 4;
yofs = 0;
} else {
xofs = 0;
yofs = (allocation.height * 3) / 4;
}
break;
case GDK_KEY_Left:
do_scroll = TRUE;
xofs = -SCROLL_STEP_SIZE;
yofs = 0;
break;
case GDK_KEY_Right:
do_scroll = TRUE;
xofs = SCROLL_STEP_SIZE;
yofs = 0;
break;
case GDK_KEY_plus:
case GDK_KEY_equal:
case GDK_KEY_KP_Add:
do_zoom = TRUE;
zoom = priv->zoom * priv->zoom_multiplier;
break;
case GDK_KEY_minus:
case GDK_KEY_KP_Subtract:
do_zoom = TRUE;
zoom = priv->zoom / priv->zoom_multiplier;
break;
case GDK_KEY_1:
do_zoom = TRUE;
zoom = 1.0;
break;
default:
return FALSE;
}
if (do_zoom) {
GdkSeat *seat;
GdkDevice *device;
gint x, y;
seat = gdk_display_get_default_seat (gtk_widget_get_display (widget));
device = gdk_seat_get_pointer (seat);
gdk_window_get_device_position (gtk_widget_get_window (widget), device,
&x, &y, NULL);
set_zoom (view, zoom, TRUE, x, y);
}
if (do_scroll)
scroll_by (view, xofs, yofs);
return TRUE;
}
/* Button press event handler for the image view */
static gboolean
eom_scroll_view_button_press_event (GtkWidget *widget, GdkEventButton *event, gpointer data)
{
EomScrollView *view;
EomScrollViewPrivate *priv;
view = EOM_SCROLL_VIEW (data);
priv = view->priv;
if (!gtk_widget_has_focus (priv->display))
gtk_widget_grab_focus (GTK_WIDGET (priv->display));
if (priv->dragging)
return FALSE;
switch (event->button) {
case 1:
case 2:
if (event->button == 1 && !priv->scroll_wheel_zoom &&
!(event->state & GDK_CONTROL_MASK))
break;
if (is_image_movable (view)) {
eom_scroll_view_set_cursor (view, EOM_SCROLL_VIEW_CURSOR_DRAG);
priv->dragging = TRUE;
priv->drag_anchor_x = event->x;
priv->drag_anchor_y = event->y;
priv->drag_ofs_x = priv->xofs;
priv->drag_ofs_y = priv->yofs;
return TRUE;
}
default:
break;
}
return FALSE;
}
/* Button release event handler for the image view */
static gboolean
eom_scroll_view_button_release_event (GtkWidget *widget, GdkEventButton *event, gpointer data)
{
EomScrollView *view;
EomScrollViewPrivate *priv;
view = EOM_SCROLL_VIEW (data);
priv = view->priv;
if (!priv->dragging)
return FALSE;
switch (event->button) {
case 1:
case 2:
drag_to (view, event->x, event->y);
priv->dragging = FALSE;
eom_scroll_view_set_cursor (view, EOM_SCROLL_VIEW_CURSOR_NORMAL);
break;
default:
break;
}
return TRUE;