view: adjust position according to declared top left corner

The XDG surface geometry includes an (x,y) coordinate indicating the top
left corner of the window. Use this information to correctly set the
view position.

Author: joggee-fr

view.c

@@ -55,17 +55,21 @@ view_activate(struct cg_view *view, bool activate)
 static bool
 view_extends_output_layout(struct cg_view *view, struct wlr_box *layout_box)
 {
-	int width, height;
-	view->impl->get_geometry(view, &width, &height);
+	struct wlr_box view_box;
+	view->impl->get_geometry(view, &view_box);
 
-	return (layout_box->height < height || layout_box->width < width);
+	return (layout_box->height < view_box.height || layout_box->width < view_box.width);
 }
 
 static void
 view_maximize(struct cg_view *view, struct wlr_box *layout_box)
 {
-	view->lx = layout_box->x;
-	view->ly = layout_box->y;
+	struct wlr_box view_box;
+	view->impl->get_geometry(view, &view_box);
+
+	// Do not forget to adjust position according to top left corner declared in view geometry
+	view->lx = layout_box->x - view_box.x;
+	view->ly = layout_box->y - view_box.y;
 
 	if (view->scene_tree) {
 		wlr_scene_node_set_position(&view->scene_tree->node, view->lx, view->ly);
@@ -77,11 +81,12 @@ view_maximize(struct cg_view *view, struct wlr_box *layout_box)
 static void
 view_center(struct cg_view *view, struct wlr_box *layout_box)
 {
-	int width, height;
-	view->impl->get_geometry(view, &width, &height);
+	struct wlr_box view_box;
+	view->impl->get_geometry(view, &view_box);
 
-	view->lx = (layout_box->width - width) / 2;
-	view->ly = (layout_box->height - height) / 2;
+	// Do not forget to adjust position according to top left corner declared in view geometry
+	view->lx = (layout_box->width - view_box.width) / 2 - view_box.x;
+	view->ly = (layout_box->height - view_box.height) / 2 - view_box.y;
 
 	if (view->scene_tree) {
 		wlr_scene_node_set_position(&view->scene_tree->node, view->lx, view->ly);

view.h

@@ -36,7 +36,7 @@ struct cg_view {
 
 struct cg_view_impl {
 	char *(*get_title)(struct cg_view *view);
-	void (*get_geometry)(struct cg_view *view, int *width_out, int *height_out);
+	void (*get_geometry)(struct cg_view *view, struct wlr_box *view_box);
 	bool (*is_primary)(struct cg_view *view);
 	bool (*is_transient_for)(struct cg_view *child, struct cg_view *parent);
 	void (*activate)(struct cg_view *view, bool activate);

xdg_shell.c

@@ -125,13 +125,12 @@ get_title(struct cg_view *view)
 }
 
 static void
-get_geometry(struct cg_view *view, int *width_out, int *height_out)
+get_geometry(struct cg_view *view, struct wlr_box *view_box)
 {
 	struct cg_xdg_shell_view *xdg_shell_view = xdg_shell_view_from_view(view);
 	struct wlr_xdg_surface *xdg_surface = xdg_shell_view->xdg_toplevel->base;
 
-	*width_out = xdg_surface->geometry.width;
-	*height_out = xdg_surface->geometry.height;
+	memcpy(view_box, &xdg_surface->geometry, sizeof(*view_box));
 }
 
 static bool

xwayland.c

@@ -38,18 +38,22 @@ get_title(struct cg_view *view)
 }
 
 static void
-get_geometry(struct cg_view *view, int *width_out, int *height_out)
+get_geometry(struct cg_view *view, struct wlr_box *view_box)
 {
 	struct cg_xwayland_view *xwayland_view = xwayland_view_from_view(view);
 	struct wlr_xwayland_surface *xsurface = xwayland_view->xwayland_surface;
+
+	view_box->x = 0;
+	view_box->y = 0;
+
 	if (xsurface->surface == NULL) {
-		*width_out = 0;
-		*height_out = 0;
+		view_box->width = 0;
+		view_box->height = 0;
 		return;
 	}
 
-	*width_out = xsurface->surface->current.width;
-	*height_out = xsurface->surface->current.height;
+	view_box->width = xsurface->surface->current.width;
+	view_box->height = xsurface->surface->current.height;
 }
 
 static bool