// // fastiv-view.c: fast image viewer - view widget // // Copyright (c) 2021, Přemysl Eric Janouch // // Permission to use, copy, modify, and/or distribute this software for any // purpose with or without fee is hereby granted. // // THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES // WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF // MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY // SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES // WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION // OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. // #include #include "fastiv-io.h" #include "fastiv-view.h" struct _FastivView { GtkWidget parent_instance; cairo_surface_t *surface; // TODO(p): Zoom-to-fit indication. double scale; }; G_DEFINE_TYPE(FastivView, fastiv_view, GTK_TYPE_WIDGET) static void get_display_dimensions(FastivView *self, int *width, int *height) { *width = *height = 0; if (!self->surface) return; cairo_rectangle_t extents = {}; switch (cairo_surface_get_type(self->surface)) { case CAIRO_SURFACE_TYPE_IMAGE: extents.width = cairo_image_surface_get_width(self->surface); extents.height = cairo_image_surface_get_height(self->surface); break; case CAIRO_SURFACE_TYPE_RECORDING: (void) cairo_recording_surface_get_extents(self->surface, &extents); break; default: g_assert_not_reached(); } *width = ceil(extents.width * self->scale); *height = ceil(extents.height * self->scale); } static void fastiv_view_finalize(GObject *gobject) { FastivView *self = FASTIV_VIEW(gobject); cairo_surface_destroy(self->surface); G_OBJECT_CLASS(fastiv_view_parent_class)->finalize(gobject); } static void fastiv_view_get_preferred_height( GtkWidget *widget, gint *minimum, gint *natural) { int width, height; get_display_dimensions(FASTIV_VIEW(widget), &width, &height); *minimum = *natural = height; } static void fastiv_view_get_preferred_width(GtkWidget *widget, gint *minimum, gint *natural) { int width, height; get_display_dimensions(FASTIV_VIEW(widget), &width, &height); *minimum = *natural = width; } static void fastiv_view_realize(GtkWidget *widget) { GtkAllocation allocation; gtk_widget_get_allocation(widget, &allocation); GdkWindowAttr attributes = { .window_type = GDK_WINDOW_CHILD, .x = allocation.x, .y = allocation.y, .width = allocation.width, .height = allocation.height, // Input-only would presumably also work (as in GtkPathBar, e.g.), // but it merely seems to involve more work. .wclass = GDK_INPUT_OUTPUT, // Assuming here that we can't ask for a higher-precision Visual // than what we get automatically. .visual = gtk_widget_get_visual(widget), .event_mask = gtk_widget_get_events(widget) | GDK_SCROLL_MASK, }; // We need this window to receive input events at all. GdkWindow *window = gdk_window_new(gtk_widget_get_parent_window(widget), &attributes, GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL); gtk_widget_register_window(widget, window); gtk_widget_set_window(widget, window); gtk_widget_set_realized(widget, TRUE); } static gboolean fastiv_view_draw(GtkWidget *widget, cairo_t *cr) { FastivView *self = FASTIV_VIEW(widget); if (!self->surface || !gtk_cairo_should_draw_window(cr, gtk_widget_get_window(widget))) return TRUE; GtkAllocation allocation; gtk_widget_get_allocation(widget, &allocation); gtk_render_background(gtk_widget_get_style_context(widget), cr, 0, 0, allocation.width, allocation.height); int w, h; get_display_dimensions(self, &w, &h); double x = 0; double y = 0; if (w < allocation.width) x = round((allocation.width - w) / 2.); if (h < allocation.height) y = round((allocation.height - h) / 2.); // FIXME: Recording surfaces do not work well with CAIRO_SURFACE_TYPE_XLIB, // we always get a shitty pixmap, where transparency contains junk. if (cairo_surface_get_type(self->surface) == CAIRO_SURFACE_TYPE_RECORDING) { cairo_surface_t *image = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, w, h); cairo_t *tcr = cairo_create(image); cairo_scale(tcr, self->scale, self->scale); cairo_set_source_surface(tcr, self->surface, 0, 0); cairo_paint(tcr); cairo_destroy(tcr); cairo_set_source_surface(cr, image, x, y); cairo_paint(cr); cairo_surface_destroy(image); return TRUE; } // XXX: The rounding together with padding may result in up to // a pixel's worth of made-up picture data. cairo_rectangle(cr, x, y, w, h); cairo_clip(cr); cairo_scale(cr, self->scale, self->scale); cairo_set_source_surface( cr, self->surface, x / self->scale, y / self->scale); cairo_pattern_t *pattern = cairo_get_source(cr); cairo_pattern_set_extend(pattern, CAIRO_EXTEND_PAD); // TODO(p): Prescale it ourselves to an off-screen bitmap, gamma-correctly. cairo_pattern_set_filter(pattern, CAIRO_FILTER_GOOD); cairo_paint(cr); return TRUE; } static gboolean fastiv_view_scroll_event(GtkWidget *widget, GdkEventScroll *event) { FastivView *self = FASTIV_VIEW(widget); if (!self->surface) return FALSE; switch (event->direction) { case GDK_SCROLL_UP: self->scale *= 1.4; gtk_widget_queue_resize(widget); return TRUE; case GDK_SCROLL_DOWN: self->scale /= 1.4; gtk_widget_queue_resize(widget); return TRUE; default: return FALSE; } } static void fastiv_view_class_init(FastivViewClass *klass) { GObjectClass *object_class = G_OBJECT_CLASS(klass); object_class->finalize = fastiv_view_finalize; GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass); widget_class->get_preferred_height = fastiv_view_get_preferred_height; widget_class->get_preferred_width = fastiv_view_get_preferred_width; widget_class->realize = fastiv_view_realize; widget_class->draw = fastiv_view_draw; widget_class->scroll_event = fastiv_view_scroll_event; // TODO(p): Later override "screen_changed", recreate Pango layouts there, // if we get to have any, or otherwise reflect DPI changes. gtk_widget_class_set_css_name(widget_class, "fastiv-view"); } static void fastiv_view_init(FastivView *self) { self->scale = 1.0; } // --- Picture loading --------------------------------------------------------- // TODO(p): Progressive picture loading, or at least async/cancellable. gboolean fastiv_view_open(FastivView *self, const gchar *path, GError **error) { cairo_surface_t *surface = fastiv_io_open(path, error); if (!surface) return FALSE; if (self->surface) cairo_surface_destroy(self->surface); self->surface = surface; self->scale = 1.0; gtk_widget_queue_resize(GTK_WIDGET(self)); return TRUE; }