Viewer: Keyboard shortcuts to change number of columns (Ctrl+[ and Ctrl+])

src/pyj/read_book/iframe.pyj

@@ -24,13 +24,14 @@ from read_book.mathjax import apply_mathjax
 from read_book.paged_mode import (
     anchor_funcs as paged_anchor_funcs,
     auto_scroll_action as paged_auto_scroll_action, calc_columns_per_screen,
-    will_columns_per_screen_change, current_cfi,
-    handle_gesture as paged_handle_gesture, handle_shortcut as paged_handle_shortcut,
-    jump_to_cfi as paged_jump_to_cfi, layout as paged_layout,
-    onwheel as paged_onwheel, prepare_for_resize as paged_prepare_for_resize,
-    progress_frac, reset_paged_mode_globals, resize_done as paged_resize_done,
+    current_cfi, get_columns_per_screen_data, handle_gesture as paged_handle_gesture,
+    handle_shortcut as paged_handle_shortcut, jump_to_cfi as paged_jump_to_cfi,
+    layout as paged_layout, onwheel as paged_onwheel,
+    prepare_for_resize as paged_prepare_for_resize, progress_frac,
+    reset_paged_mode_globals, resize_done as paged_resize_done,
     scroll_by_page as paged_scroll_by_page, scroll_to_elem,
-    scroll_to_fraction as paged_scroll_to_fraction, snap_to_selection
+    scroll_to_fraction as paged_scroll_to_fraction, snap_to_selection,
+    will_columns_per_screen_change
 )
 from read_book.referencing import (
     elem_for_ref, end_reference_mode, start_reference_mode
@@ -100,7 +101,8 @@ class IframeBoss:
         handlers = {
             'change_color_scheme': self.change_color_scheme,
             'change_font_size': self.change_font_size,
-            'viewer_font_size_changed': self.viewer_font_size_changed,
+            'change_number_of_columns': self.change_number_of_columns,
+            'number_of_columns_changed': self.number_of_columns_changed,
             'change_scroll_speed': self.change_scroll_speed,
             'display': self.display,
             'find': self.find,
@@ -276,9 +278,18 @@ class IframeBoss:
                 # apply_font_size() is a no-op
                 self.relayout_on_font_size_change()
 
-    def viewer_font_size_changed(self, data):
-        opts.base_font_size = data.base_font_size
+    def change_number_of_columns(self, data):
+        if current_layout_mode() is 'flow':
+            return
+        cdata = get_columns_per_screen_data()
+        delta = int(data.delta)
+        if delta is 0:
+            new_val = 0
+        else:
+            new_val = max(1, cdata.cps + delta)
+        opts.columns_per_screen[cdata.which] = new_val
         self.relayout_on_font_size_change()
+        self.send_message('columns_per_screen_changed', which=cdata.which, cps=new_val)
 
     def relayout_on_font_size_change(self):
         if current_layout_mode() is not 'flow' and will_columns_per_screen_change():
@@ -290,6 +301,10 @@ class IframeBoss:
             self.update_cfi()
             self.update_toc_position()
 
+    def number_of_columns_changed(self, data):
+        opts.columns_per_screen = data.columns_per_screen
+        self.relayout_on_font_size_change()
+
     def change_scroll_speed(self, data):
         if data.lines_per_sec_auto?:
             opts.lines_per_sec_auto = data.lines_per_sec_auto

src/pyj/read_book/paged_mode.pyj

@@ -152,6 +152,11 @@ def calc_columns_per_screen():
     return cps
 
 
+def get_columns_per_screen_data():
+    which = 'landscape' if scroll_viewport.width() > scroll_viewport.height() else 'portrait'
+    return {'which': which, 'cps': calc_columns_per_screen()}
+
+
 def will_columns_per_screen_change():
     return calc_columns_per_screen() != cols_per_screen
 

src/pyj/read_book/shortcuts.pyj

@@ -216,6 +216,24 @@ def shortcuts_definition():
         _('Decrease font size'),
     ),
 
+    'increase_number_of_columns': desc(
+        v"['Ctrl+]']",
+        'ui',
+        _('Increase number of columns'),
+    ),
+
+    'decrease_number_of_columns': desc(
+        v"['Ctrl+[']",
+        'ui',
+        _('Decrease number of columns'),
+    ),
+
+    'reset_number_of_columns': desc(
+        v"['Ctrl+Alt+c']",
+        'ui',
+        _('Make number of columns automatic'),
+    ),
+
     'toggle_full_screen': desc(
         v"['F11', 'Ctrl+Shift+F']",
         'ui',

src/pyj/read_book/view.pyj

@@ -237,6 +237,7 @@ class View:
             'request_size': self.on_request_size,
             'scroll_to_anchor': self.on_scroll_to_anchor,
             'selectionchange': self.on_selection_change,
+            'columns_per_screen_changed': self.on_columns_per_screen_changed,
             'show_chrome': self.show_chrome,
             'show_footnote': self.on_show_footnote,
             'update_cfi': self.on_update_cfi,
@@ -453,6 +454,12 @@ class View:
             self.toggle_autoscroll()
         elif data.name.startsWith('switch_color_scheme:'):
             self.switch_color_scheme(data.name.partition(':')[-1])
+        elif data.name is 'increase_number_of_columns':
+            self.iframe_wrapper.send_message('change_number_of_columns', delta=1)
+        elif data.name is 'decrease_number_of_columns':
+            self.iframe_wrapper.send_message('change_number_of_columns', delta=-1)
+        elif data.name is 'reset_number_of_columns':
+            self.iframe_wrapper.send_message('change_number_of_columns', delta=0)
         else:
             self.iframe_wrapper.send_message('handle_navigation_shortcut', name=data.name)
 
@@ -461,6 +468,12 @@ class View:
         if ui_operations.selection_changed:
             ui_operations.selection_changed(data.text)
 
+    def on_columns_per_screen_changed(self, data):
+        sd = get_session_data()
+        cps = sd.get('columns_per_screen') or {}
+        cps[data.which] = int(data.cps)
+        sd.set('columns_per_screen', cps)
+
     def switch_color_scheme(self, name):
         get_session_data().set('current_color_scheme', name)
         ui_operations.redisplay_book()