ev-document-misc.c

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/*
 *  Copyright (C) 2009 Juanjo Marín <juanj.marin@juntadeandalucia.es>
 *  Copyright (c) 2007 Carlos Garcia Campos <carlosgc@gnome.org>
 *  Copyright (C) 2000-2003 Marco Pesenti Gritti
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

#include <config.h>

#include <string.h>
#include <math.h>

#include <gtk/gtk.h>

#include "ev-document-misc.h"

/* Returns a new GdkPixbuf that is suitable for placing in the thumbnail view.
 * It is four pixels wider and taller than the source.  If source_pixbuf is not
 * NULL, then it will fill the return pixbuf with the contents of
 * source_pixbuf.
 */
static GdkPixbuf *
create_thumbnail_frame (int        width,
            int        height,
            GdkPixbuf *source_pixbuf,
            gboolean   fill_bg)
{
    GdkPixbuf *retval;
    guchar *data;
    gint rowstride;
    int i;
    int width_r, height_r;

    if (source_pixbuf)
        g_return_val_if_fail (GDK_IS_PIXBUF (source_pixbuf), NULL);

    if (source_pixbuf) {
        width_r = gdk_pixbuf_get_width (source_pixbuf);
        height_r = gdk_pixbuf_get_height (source_pixbuf);
    } else {
        width_r = width;
        height_r = height;
    }

    /* make sure no one is passing us garbage */
    g_return_val_if_fail (width_r >= 0 && height_r >= 0, NULL);

    retval = gdk_pixbuf_new (GDK_COLORSPACE_RGB,
                 TRUE, 8,
                 width_r + 4,
                 height_r + 4);

    /* make it black and fill in the middle */
    data = gdk_pixbuf_get_pixels (retval);
    rowstride = gdk_pixbuf_get_rowstride (retval);

    gdk_pixbuf_fill (retval, 0x000000ff);
    if (fill_bg) {
        for (i = 1; i < height_r + 1; i++)
            memset (data + (rowstride * i) + 4, 0xffffffff, width_r * 4);
    }

    /* copy the source pixbuf */
    if (source_pixbuf)
        gdk_pixbuf_copy_area (source_pixbuf, 0, 0,
                      width_r,
                      height_r,
                      retval,
                      1, 1);
    /* Add the corner */
    data [(width_r + 2) * 4 + 3] = 0;
    data [(width_r + 3) * 4 + 3] = 0;
    data [(width_r + 2) * 4 + (rowstride * 1) + 3] = 0;
    data [(width_r + 3) * 4 + (rowstride * 1) + 3] = 0;

    data [(height_r + 2) * rowstride + 3] = 0;
    data [(height_r + 3) * rowstride + 3] = 0;
    data [(height_r + 2) * rowstride + 4 + 3] = 0;
    data [(height_r + 3) * rowstride + 4 + 3] = 0;

    return retval;
}

GdkPixbuf *
ev_document_misc_get_thumbnail_frame (int        width,
                      int        height,
                      GdkPixbuf *source_pixbuf)
{
    return create_thumbnail_frame (width, height, source_pixbuf, TRUE);
}

GdkPixbuf *
ev_document_misc_get_loading_thumbnail (int      width,
                    int      height,
                    gboolean inverted_colors)
{
    return create_thumbnail_frame (width, height, NULL, !inverted_colors);
}

static cairo_surface_t *
ev_document_misc_render_thumbnail_frame (GtkWidget       *widget,
                                         int              width,
                                         int              height,
                                         gboolean         inverted_colors,
                                         GdkPixbuf       *source_pixbuf,
                                         cairo_surface_t *source_surface)
{
        GtkStyleContext *context = gtk_widget_get_style_context (widget);
        GtkStateFlags    state = gtk_widget_get_state_flags (widget);
        double           width_r, height_r;
        double           width_f, height_f;
        cairo_surface_t *surface;
        cairo_t         *cr;
        double           device_scale_x = 1;
        double           device_scale_y = 1;
        GtkBorder        border = {0, };

        if (source_surface) {
                width_r = cairo_image_surface_get_width (source_surface);
                height_r = cairo_image_surface_get_height (source_surface);
#ifdef HAVE_HIDPI_SUPPORT
                cairo_surface_get_device_scale (source_surface, &device_scale_x, &device_scale_y);
#endif
        } else if (source_pixbuf) {
                g_return_val_if_fail (GDK_IS_PIXBUF (source_pixbuf), NULL);

                width_r = gdk_pixbuf_get_width (source_pixbuf);
                height_r = gdk_pixbuf_get_height (source_pixbuf);
#ifdef HAVE_HIDPI_SUPPORT
                device_scale_x = device_scale_y = gtk_widget_get_scale_factor (widget);
#endif
        } else {
                width_r = width;
                height_r = height;
#ifdef HAVE_HIDPI_SUPPORT
                device_scale_x = device_scale_y = gtk_widget_get_scale_factor (widget);
#endif
        }

        width_r /= device_scale_x;
        height_r /= device_scale_y;

        gtk_style_context_save (context);

        gtk_style_context_add_class (context, "page-thumbnail");
        if (inverted_colors)
                gtk_style_context_add_class (context, "inverted");

        gtk_style_context_get_border (context, state, &border);
        width_f = width_r + border.left + border.right;
        height_f = height_r + border.top + border.bottom;

        surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
                                              device_scale_x * width_f,
                                              device_scale_y * height_f);

#ifdef HAVE_HIDPI_SUPPORT
        cairo_surface_set_device_scale (surface, device_scale_x, device_scale_y);
#endif

        cr = cairo_create (surface);
        if (source_surface) {
                cairo_set_source_surface (cr, source_surface, border.left, border.top);
                cairo_paint (cr);
        } else if (source_pixbuf) {
                gdk_cairo_set_source_pixbuf (cr, source_pixbuf, border.left, border.top);
                cairo_paint (cr);
        } else {
                gtk_render_background (context, cr, 0, 0, width_f, height_f);
        }
        gtk_render_frame (context, cr, 0, 0, width_f, height_f);
        cairo_destroy (cr);

        gtk_style_context_restore (context);

        return surface;
}

GdkPixbuf *
ev_document_misc_render_loading_thumbnail (GtkWidget *widget,
                                           int        width,
                                           int        height,
                                           gboolean   inverted_colors)
{
        GdkPixbuf *retval;
        cairo_surface_t *surface;

        surface = ev_document_misc_render_thumbnail_frame (widget, width, height, inverted_colors, NULL, NULL);
        retval = gdk_pixbuf_get_from_surface (surface, 0, 0, width, height);
        cairo_surface_destroy (surface);

        return retval;
}

cairo_surface_t *
ev_document_misc_render_loading_thumbnail_surface (GtkWidget *widget,
                                                   int        width,
                                                   int        height,
                                                   gboolean   inverted_colors)
{
        return ev_document_misc_render_thumbnail_frame (widget, width, height, inverted_colors, NULL, NULL);
}

GdkPixbuf *
ev_document_misc_render_thumbnail_with_frame (GtkWidget *widget,
                                              GdkPixbuf *source_pixbuf)
{
        GdkPixbuf *retval;
        cairo_surface_t *surface;

        surface = ev_document_misc_render_thumbnail_frame (widget, -1, -1, FALSE, source_pixbuf, NULL);
        retval = gdk_pixbuf_get_from_surface (surface, 0, 0,
                                              cairo_image_surface_get_width (surface),
                                              cairo_image_surface_get_height (surface));
        cairo_surface_destroy (surface);

        return retval;
}

cairo_surface_t *
ev_document_misc_render_thumbnail_surface_with_frame (GtkWidget       *widget,
                                                      cairo_surface_t *source_surface,
                                                      int              width,
                                                      int              height)
{
        return ev_document_misc_render_thumbnail_frame (widget, width, height, FALSE, NULL, source_surface);
}

void
ev_document_misc_get_page_border_size (gint       page_width,
                       gint       page_height,
                       GtkBorder *border)
{
    g_assert (border);

    border->left = 1;
    border->top = 1;
    if (page_width < 100) {
        border->right = 2;
        border->bottom = 2;
    } else if (page_width < 500) {
        border->right = 3;
        border->bottom = 3;
    } else {
        border->right = 4;
        border->bottom = 4;
    }
}


void
ev_document_misc_paint_one_page (cairo_t      *cr,
                 GtkWidget    *widget,
                 GdkRectangle *area,
                 GtkBorder    *border,
                 gboolean      highlight,
                 gboolean      inverted_colors)
{
    GtkStyleContext *context = gtk_widget_get_style_context (widget);
    GtkStateFlags state = gtk_widget_get_state_flags (widget);
        GdkRGBA fg, bg, shade_bg;

        gtk_style_context_get_background_color (context, state, &bg);
        gtk_style_context_get_color (context, state, &fg);
        gtk_style_context_get_color (context, GTK_STATE_FLAG_INSENSITIVE, &shade_bg);

    gdk_cairo_set_source_rgba (cr, highlight ? &fg : &shade_bg);
    gdk_cairo_rectangle (cr, area);
    cairo_fill (cr);

    if (inverted_colors)
        cairo_set_source_rgb (cr, 0, 0, 0);
    else
        cairo_set_source_rgb (cr, 1, 1, 1);
    cairo_rectangle (cr,
             area->x + border->left,
             area->y + border->top,
             area->width - (border->left + border->right),
             area->height - (border->top + border->bottom));
    cairo_fill (cr);

    gdk_cairo_set_source_rgba (cr, &bg);
    cairo_rectangle (cr,
             area->x,
             area->y + area->height - (border->bottom - border->top),
             border->bottom - border->top,
             border->bottom - border->top);
    cairo_fill (cr);

    cairo_rectangle (cr,
             area->x + area->width - (border->right - border->left),
             area->y,
             border->right - border->left,
             border->right - border->left);
    cairo_fill (cr);
}

cairo_surface_t *
ev_document_misc_surface_from_pixbuf (GdkPixbuf *pixbuf)
{
    cairo_surface_t *surface;
    cairo_t         *cr;

    g_return_val_if_fail (GDK_IS_PIXBUF (pixbuf), NULL);

    surface = cairo_image_surface_create (gdk_pixbuf_get_has_alpha (pixbuf) ?
                          CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24,
                          gdk_pixbuf_get_width (pixbuf),
                          gdk_pixbuf_get_height (pixbuf));
    cr = cairo_create (surface);
    gdk_cairo_set_source_pixbuf (cr, pixbuf, 0, 0);
    cairo_paint (cr);
    cairo_destroy (cr);
    
    return surface;
}

GdkPixbuf *
ev_document_misc_pixbuf_from_surface (cairo_surface_t *surface)
{
    g_return_val_if_fail (surface, NULL);   

        return gdk_pixbuf_get_from_surface (surface,
                                            0, 0,
                                            cairo_image_surface_get_width (surface),
                                            cairo_image_surface_get_height (surface));
}

cairo_surface_t *
ev_document_misc_surface_rotate_and_scale (cairo_surface_t *surface,
                       gint             dest_width,
                       gint             dest_height,
                       gint             dest_rotation)
{
    cairo_surface_t *new_surface;
    cairo_t         *cr;
    gint             width, height;
    gint             new_width = dest_width;
    gint             new_height = dest_height;

    width = cairo_image_surface_get_width (surface);
    height = cairo_image_surface_get_height (surface);
    
    if (dest_width == width &&
        dest_height == height &&
        dest_rotation == 0) {
        return cairo_surface_reference (surface);
    }

    if (dest_rotation == 90 || dest_rotation == 270) {
        new_width = dest_height;
        new_height = dest_width;
    }

    new_surface = cairo_surface_create_similar (surface,
                            cairo_surface_get_content (surface),
                            new_width, new_height);

    cr = cairo_create (new_surface);
    switch (dest_rotation) {
            case 90:
            cairo_translate (cr, new_width, 0);
            break;
            case 180:
            cairo_translate (cr, new_width, new_height);
            break;
            case 270:
            cairo_translate (cr, 0, new_height);
            break;
            default:
            cairo_translate (cr, 0, 0);
    }
    cairo_rotate (cr, dest_rotation * G_PI / 180.0);
    
    if (dest_width != width || dest_height != height) {
        cairo_pattern_set_filter (cairo_get_source (cr), CAIRO_FILTER_BILINEAR);
        cairo_scale (cr,
                 (gdouble)dest_width / width,
                 (gdouble)dest_height / height);
    }
    
    cairo_set_source_surface (cr, surface, 0, 0);
    cairo_paint (cr);
    cairo_destroy (cr);

    return new_surface;
}

void
ev_document_misc_invert_surface (cairo_surface_t *surface) {
    cairo_t *cr;

    cr = cairo_create (surface);

    /* white + DIFFERENCE -> invert */
    cairo_set_operator (cr, CAIRO_OPERATOR_DIFFERENCE);
    cairo_set_source_rgb (cr, 1., 1., 1.);
    cairo_paint(cr);
    cairo_destroy (cr);
}

void
ev_document_misc_invert_pixbuf (GdkPixbuf *pixbuf)
{
    guchar *data, *p;
    guint   width, height, x, y, rowstride, n_channels;

    n_channels = gdk_pixbuf_get_n_channels (pixbuf);
    g_assert (gdk_pixbuf_get_colorspace (pixbuf) == GDK_COLORSPACE_RGB);
    g_assert (gdk_pixbuf_get_bits_per_sample (pixbuf) == 8);

    /* First grab a pointer to the raw pixel data. */
    data = gdk_pixbuf_get_pixels (pixbuf);

    /* Find the number of bytes per row (could be padded). */
    rowstride = gdk_pixbuf_get_rowstride (pixbuf);

    width = gdk_pixbuf_get_width (pixbuf);
    height = gdk_pixbuf_get_height (pixbuf);
    for (x = 0; x < width; x++) {
        for (y = 0; y < height; y++) {
            /* Calculate pixel's offset into the data array. */
            p = data + x * n_channels + y * rowstride;
            /* Change the RGB values*/
            p[0] = 255 - p[0];
            p[1] = 255 - p[1];
            p[2] = 255 - p[2];
        }
    }
}

gdouble
ev_document_misc_get_screen_dpi (GdkScreen *screen)
{
    gdouble dp, di;

    /*diagonal in pixels*/
    dp = hypot (gdk_screen_get_width (screen), gdk_screen_get_height (screen));

    /*diagonal in inches*/
    di = hypot (gdk_screen_get_width_mm(screen), gdk_screen_get_height_mm (screen)) / 25.4;

    return (dp / di);
}

/* Returns a locale specific date and time representation */
gchar *
ev_document_misc_format_date (GTime utime)
{
    time_t time = (time_t) utime;
    char s[256];
    const char fmt_hack[] = "%c";
    size_t len;
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wformat-y2k"
#ifdef HAVE_LOCALTIME_R
    struct tm t;
    if (time == 0 || !localtime_r (&time, &t)) return NULL;
    len = strftime (s, sizeof (s), fmt_hack, &t);
#else
    struct tm *t;
    if (time == 0 || !(t = localtime (&time)) ) return NULL;
    len = strftime (s, sizeof (s), fmt_hack, t);
#endif
#pragma GCC diagnostic pop

    if (len == 0 || s[0] == '\0') return NULL;

    return g_locale_to_utf8 (s, -1, NULL, NULL, NULL);
}

void
ev_document_misc_get_pointer_position (GtkWidget *widget,
                                       gint      *x,
                                       gint      *y)
{
        GdkDeviceManager *device_manager;
        GdkDevice        *device_pointer;
        GdkRectangle      allocation;

        if (x)
                *x = -1;
        if (y)
                *y = -1;

        if (!gtk_widget_get_realized (widget))
                return;

        device_manager = gdk_display_get_device_manager (gtk_widget_get_display (widget));
        device_pointer = gdk_device_manager_get_client_pointer (device_manager);
        gdk_window_get_device_position (gtk_widget_get_window (widget),
                                        device_pointer,
                                        x, y, NULL);

        if (gtk_widget_get_has_window (widget))
                return;

        gtk_widget_get_allocation (widget, &allocation);
        if (x)
                *x -= allocation.x;
        if (y)
                *y -= allocation.y;
}