From 9cdc641b0a233d46dffc3595574af30b66369190 Mon Sep 17 00:00:00 2001 From: Přemysl Eric Janouch Date: Mon, 3 Oct 2022 22:57:39 +0200 Subject: Center view rotations/flips --- fiv-io.h | 3 +- fiv-view.c | 131 ++++++++++++++++++++++++++++++++++++++++++++----------------- 2 files changed, 97 insertions(+), 37 deletions(-) diff --git a/fiv-io.h b/fiv-io.h index 4e031f9..7788a76 100644 --- a/fiv-io.h +++ b/fiv-io.h @@ -165,7 +165,8 @@ typedef enum _FivIoOrientation { FivIoOrientation270 = 8 } FivIoOrientation; -/// Returns a rendering matrix for a surface, and its target dimensions. +/// Returns a rendering matrix for a surface (user space to pattern space), +/// and its target dimensions. cairo_matrix_t fiv_io_orientation_apply(cairo_surface_t *surface, FivIoOrientation orientation, double *width, double *height); void fiv_io_orientation_dimensions(cairo_surface_t *surface, diff --git a/fiv-view.c b/fiv-view.c index 14e4db9..d90af18 100644 --- a/fiv-view.c +++ b/fiv-view.c @@ -191,20 +191,19 @@ get_display_dimensions(FivView *self, int *width, int *height) static void update_adjustments(FivView *self) { - int w = 0, h = 0; - get_display_dimensions(self, &w, &h); - + int dw = 0, dh = 0; + get_display_dimensions(self, &dw, &dh); GtkAllocation alloc; gtk_widget_get_allocation(GTK_WIDGET(self), &alloc); if (self->hadjustment) { gtk_adjustment_configure(self->hadjustment, - gtk_adjustment_get_value(self->hadjustment), 0, w, + gtk_adjustment_get_value(self->hadjustment), 0, dw, alloc.width * 0.1, alloc.width * 0.9, alloc.width); } if (self->vadjustment) { gtk_adjustment_configure(self->vadjustment, - gtk_adjustment_get_value(self->vadjustment), 0, h, + gtk_adjustment_get_value(self->vadjustment), 0, dh, alloc.height * 0.1, alloc.height * 0.9, alloc.height); } } @@ -576,8 +575,8 @@ fiv_view_draw(GtkWidget *widget, cairo_t *cr) !gtk_cairo_should_draw_window(cr, gtk_widget_get_window(widget))) return TRUE; - int w, h; - get_display_dimensions(self, &w, &h); + int dw, dh; + get_display_dimensions(self, &dw, &dh); double x = 0; double y = 0; @@ -585,11 +584,13 @@ fiv_view_draw(GtkWidget *widget, cairo_t *cr) x = -floor(gtk_adjustment_get_value(self->hadjustment)); if (self->vadjustment) y = -floor(gtk_adjustment_get_value(self->vadjustment)); - if (w < allocation.width) - x = round((allocation.width - w) / 2.); - if (h < allocation.height) - y = round((allocation.height - h) / 2.); + if (dw < allocation.width) + x = round((allocation.width - dw) / 2.); + if (dh < allocation.height) + y = round((allocation.height - dh) / 2.); + // XXX: This naming is confusing, because it isn't actually for the surface, + // but rather for our possibly rotated rendition of it. Dimensions surface_dimensions = {}; cairo_matrix_t matrix = fiv_io_orientation_apply( self->page_scaled ? self->page_scaled : self->page, self->orientation, @@ -599,7 +600,7 @@ fiv_view_draw(GtkWidget *widget, cairo_t *cr) if (self->checkerboard) { gtk_style_context_save(style); gtk_style_context_add_class(style, "checkerboard"); - gtk_render_background(style, cr, 0, 0, w, h); + gtk_render_background(style, cr, 0, 0, dw, dh); gtk_style_context_restore(style); } @@ -615,7 +616,7 @@ fiv_view_draw(GtkWidget *widget, cairo_t *cr) // we always get a shitty pixmap, where transparency contains junk. if (cairo_surface_get_type(self->frame) == CAIRO_SURFACE_TYPE_RECORDING) { cairo_surface_t *image = - cairo_image_surface_create(CAIRO_FORMAT_ARGB32, w, h); + cairo_image_surface_create(CAIRO_FORMAT_ARGB32, dw, dh); cairo_t *tcr = cairo_create(image); cairo_scale(tcr, self->scale, self->scale); cairo_set_source_surface(tcr, self->frame, 0, 0); @@ -631,7 +632,7 @@ fiv_view_draw(GtkWidget *widget, cairo_t *cr) // XXX: The rounding together with padding may result in up to // a pixel's worth of made-up picture data. - cairo_rectangle(cr, 0, 0, w, h); + cairo_rectangle(cr, 0, 0, dw, dh); cairo_clip(cr); cairo_scale(cr, self->scale, self->scale); @@ -689,6 +690,28 @@ set_scale_to_fit(FivView *self, bool scale_to_fit) return TRUE; } +static void +widget_to_surface(FivView *self, double *x, double *y) +{ + int dw, dh; + get_display_dimensions(self, &dw, &dh); + GtkAllocation allocation; + gtk_widget_get_allocation(GTK_WIDGET(self), &allocation); + + // Unneeded, thus unimplemented: this means zero adjustment values. + if (!self->hadjustment || !self->vadjustment) + return; + + *x = (*x + (dw < allocation.width + ? -round((allocation.width - dw) / 2.) + : +floor(gtk_adjustment_get_value(self->hadjustment)))) + / self->scale; + *y = (*y + (dh < allocation.height + ? -round((allocation.height - dh) / 2.) + : +floor(gtk_adjustment_get_value(self->vadjustment)))) + / self->scale; +} + static gboolean set_scale(FivView *self, double scale, const GdkEvent *event) { @@ -703,34 +726,25 @@ set_scale(FivView *self, double scale, const GdkEvent *event) GtkAllocation allocation; gtk_widget_get_allocation(GTK_WIDGET(self), &allocation); - - double focus_x = 0, focus_y = 0, surface_x = 0, surface_y = 0; + double focus_x = 0, focus_y = 0; if (!event || !gdk_event_get_coords(event, &focus_x, &focus_y)) { focus_x = 0.5 * allocation.width; focus_y = 0.5 * allocation.height; } - if (self->hadjustment && self->vadjustment) { - int w, h; - get_display_dimensions(self, &w, &h); - - surface_x = (focus_x + (w < allocation.width - ? -round((allocation.width - w) / 2.) - : +floor(gtk_adjustment_get_value(self->hadjustment)))) - / self->scale; - surface_y = (focus_y + (h < allocation.height - ? -round((allocation.height - h) / 2.) - : +floor(gtk_adjustment_get_value(self->vadjustment)))) - / self->scale; - } + + double surface_x = focus_x; + double surface_y = focus_y; + widget_to_surface(self, &surface_x, &surface_y); self->scale = scale; g_object_notify_by_pspec(G_OBJECT(self), view_properties[PROP_SCALE]); prescale_page(self); + // Similar to set_orientation(). if (self->hadjustment && self->vadjustment) { + Dimensions surface_dimensions = get_surface_dimensions(self); update_adjustments(self); - Dimensions surface_dimensions = get_surface_dimensions(self); if (surface_dimensions.width * self->scale > allocation.width) gtk_adjustment_set_value( self->hadjustment, surface_x * self->scale - focus_x); @@ -1036,6 +1050,7 @@ on_draw_page(G_GNUC_UNUSED GtkPrintOperation *operation, // Any DPI will be wrong, unless we import that information from the image. double scale = 1 / 96.; Dimensions surface_dimensions = {}; + // XXX: Perhaps use self->frame, even though their sizes should match. cairo_matrix_t matrix = fiv_io_orientation_apply(self->page, self->orientation, &surface_dimensions.width, &surface_dimensions.height); @@ -1457,6 +1472,53 @@ swap_enhanced_image(FivView *self) } } +static void +transformed_to_real(FivView *self, double *x, double *y) +{ + double sw = 0, sh = 0; + cairo_matrix_t matrix = + fiv_io_orientation_apply(self->page, self->orientation, &sw, &sh); + cairo_matrix_transform_point(&matrix, x, y); +} + +static void +set_orientation(FivView *self, FivIoOrientation orientation) +{ + GtkAllocation allocation; + gtk_widget_get_allocation(GTK_WIDGET(self), &allocation); + + // In the future, rotating gestures can pick another centre point. + double focus_x = 0.5 * allocation.width; + double focus_y = 0.5 * allocation.height; + + double surface_x = focus_x; + double surface_y = focus_y; + widget_to_surface(self, &surface_x, &surface_y); + transformed_to_real(self, &surface_x, &surface_y); + + self->orientation = orientation; + + // Similar to set_scale(). + Dimensions surface_dimensions = {}; + cairo_matrix_t matrix = + fiv_io_orientation_apply(self->page, self->orientation, + &surface_dimensions.width, &surface_dimensions.height); + if (self->hadjustment && self->vadjustment && + cairo_matrix_invert(&matrix) == CAIRO_STATUS_SUCCESS) { + cairo_matrix_transform_point(&matrix, &surface_x, &surface_y); + update_adjustments(self); + + if (surface_dimensions.width * self->scale > allocation.width) + gtk_adjustment_set_value( + self->hadjustment, surface_x * self->scale - focus_x); + if (surface_dimensions.height * self->scale > allocation.height) + gtk_adjustment_set_value( + self->vadjustment, surface_y * self->scale - focus_y); + } + + gtk_widget_queue_resize(GTK_WIDGET(self)); +} + void fiv_view_command(FivView *self, FivViewCommand command) { @@ -1471,14 +1533,11 @@ fiv_view_command(FivView *self, FivViewCommand command) reload(self); break; case FIV_VIEW_COMMAND_ROTATE_LEFT: - self->orientation = view_left[self->orientation]; - gtk_widget_queue_resize(widget); + set_orientation(self, view_left[self->orientation]); break; case FIV_VIEW_COMMAND_MIRROR: - self->orientation = view_mirror[self->orientation]; - gtk_widget_queue_resize(widget); + set_orientation(self, view_mirror[self->orientation]); break; case FIV_VIEW_COMMAND_ROTATE_RIGHT: - self->orientation = view_right[self->orientation]; - gtk_widget_queue_resize(widget); + set_orientation(self, view_right[self->orientation]); break; case FIV_VIEW_COMMAND_PAGE_FIRST: switch_page(self, self->image); -- cgit v1.2.3-70-g09d2