UI: New Global Top-Bar (WIP)

== Main Features/Changes for Users

* Add horizontal bar at top of all non-temp windows, consisting out of two horizontal sub-bars.
* Upper sub-bar contains global menus (File, Render, etc.), tabs for workspaces and scene selector.
* Lower sub-bar contains object mode selector, screen-layout and render-layer selector. Later operator and/or tool settings will be placed here.
* Individual sections of the topbar are individually scrollable.
* Workspace tabs can be double- or ctrl-clicked for renaming and contain 'x' icon for deleting.
* Top-bar should scale nicely with DPI.
* The lower half of the top-bar can be hided by dragging the lower top-bar edge up. Better hiding options are planned (e.g. hide in fullscreen modes).
* Info editors at the top of the window and using the full window width with be replaced by the top-bar.
* In fullscreen modes, no more info editor is added on top, the top-bar replaces it.

== Technical Features/Changes

* Adds initial support for global areas

  A global area is part of the window, not part of the regular screen-layout.
  I've added a macro iterator to iterate over both, global and screen-layout level areas. When iterating over areas, from now on developers should always consider if they have to include global areas.
* Adds a TOPBAR editor type

  The editor type is hidden in the UI editor type menu.
* Adds a variation of the ID template to display IDs as tab buttons (template_ID_tabs in BPY)
* Does various changes to RNA button creation code to improve their appearance in the horizontal top-bar.
* Adds support for dynamically sized regions. That is, regions that scale automatically to the layout bounds.

  The code for this is currently a big hack (it's based on drawing the UI multiple times). This should definitely be improved.
* Adds a template for displaying operator properties optimized for the top-bar. This will probably change a lot still and is in fact disabled in code.

Since the final top-bar design depends a lot on other 2.8 designs (mainly tool-system and workspaces), we decided to not show the operator or tool settings in the top-bar for now. That means most of the lower sub-bar is empty for the time being.

NOTE: Top-bar or global area data is not written to files or SDNA. They are simply added to the window when opening Blender or reading a file. This allows us doing changes to the top-bar without having to care for compatibility.

== ToDo's

It's a bit hard to predict all the ToDo's here are the known main ones:
* Add options for the new active-tool system and for operator redo to the topbar.
* Automatically hide the top-bar in fullscreen modes.
* General visual polish.
* Top-bar drag & drop support (WIP in temp-tab_drag_drop).
* Improve dynamic regions (should also fix some layout glitches).
* Make internal terminology consistent.
* Enable topbar file writing once design is more advanced.
* Address TODO's and XXX's in code :)

Thanks @brecht for the review! And @sergey for the complaining ;)

Differential Revision: D2758

3 files changed, 405 insertions, 0 deletions

diff --git a/release/scripts/startup/bl_ui/__init__.py b/release/scripts/startup/bl_ui/__init__.py
index 5c50cb74fdb..2c0b1ab12be 100644
--- a/release/scripts/startup/bl_ui/__init__.py
+++ b/release/scripts/startup/bl_ui/__init__.py
@@ -84,6 +84,7 @@ _modules = [
     "space_sequencer",
     "space_text",
     "space_time",
+    "space_topbar",
     "space_userpref",
     "space_view3d",
     "space_view3d_toolbar",
diff --git a/release/scripts/startup/bl_ui/space_topbar.py b/release/scripts/startup/bl_ui/space_topbar.py
new file mode 100644
index 00000000000..7ce512ebb2a
--- /dev/null
+++ b/release/scripts/startup/bl_ui/space_topbar.py
@@ -0,0 +1,401 @@
+# ##### BEGIN GPL LICENSE BLOCK #####
+#
+#  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
+#  of the License, 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.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+# <pep8 compliant>
+import bpy
+from bpy.types import Header, Menu, Panel
+
+
+class TOPBAR_HT_upper_bar(Header):
+    bl_space_type = 'TOPBAR'
+
+    def draw(self, context):
+        region = context.region
+
+        if region.alignment == 'RIGHT':
+            self.draw_right(context)
+        else:
+            self.draw_left(context)
+
+    def draw_left(self, context):
+        layout = self.layout
+
+        window = context.window
+        screen = context.screen
+
+        layout.operator("wm.splash", text="", icon='BLENDER', emboss=False)
+
+        TOPBAR_MT_editor_menus.draw_collapsible(context, layout)
+
+        layout.separator()
+
+        if not screen.show_fullscreen:
+            layout.template_ID_tabs(window, "workspace", new="workspace.workspace_add_menu", unlink="workspace.workspace_delete")
+
+        layout.separator()
+
+        layout.template_running_jobs()
+
+        layout.template_reports_banner()
+
+        row = layout.row(align=True)
+
+        if bpy.app.autoexec_fail is True and bpy.app.autoexec_fail_quiet is False:
+            row.label("Auto-run disabled", icon='ERROR')
+            if bpy.data.is_saved:
+                props = row.operator("wm.revert_mainfile", icon='SCREEN_BACK', text="Reload Trusted")
+                props.use_scripts = True
+
+            row.operator("script.autoexec_warn_clear", text="Ignore")
+
+            # include last so text doesn't push buttons out of the header
+            row.label(bpy.app.autoexec_fail_message)
+            return
+
+    def draw_right(self, context):
+        layout = self.layout
+
+        window = context.window
+
+        layout.template_ID(window, "scene", new="scene.new", unlink="scene.delete")
+
+
+class TOPBAR_HT_lower_bar(Header):
+    bl_space_type = 'TOPBAR'
+    bl_region_type = 'WINDOW'
+
+    def draw(self, context):
+        layout = self.layout
+        region = context.region
+
+        if region.alignment == 'LEFT':
+            self.draw_left(context)
+        elif region.alignment == 'RIGHT':
+            self.draw_right(context)
+        else:
+            # WITH_REDO_REGION_REMOVAL:
+            # layout.template_operator_redo_props()
+            pass
+
+    def draw_left(self, context):
+        layout = self.layout
+        layer = context.view_layer
+
+        act_mode_item = bpy.types.Object.bl_rna.properties['mode'].enum_items[layer.objects.active.mode]
+        layout.operator_menu_enum("object.mode_set", "mode", text=act_mode_item.name, icon=act_mode_item.icon)
+
+
+    def draw_right(self, context):
+        layout = self.layout
+
+        window = context.window
+        workspace = context.workspace
+        scene = context.scene
+        screen = context.screen
+
+        if screen.show_fullscreen:
+            layout.operator("screen.back_to_previous", icon='SCREEN_BACK', text="Back to Previous")
+        else:
+            layout.template_search_preview(window, "screen", workspace, "screens", new="screen.new", unlink="screen.delete", rows=2, cols=6)
+        # Active workspace view-layer is retrieved through window, not through workspace.
+        layout.template_search(window, "view_layer", scene, "view_layers")
+
+
+class TOPBAR_MT_editor_menus(Menu):
+    bl_idname = "TOPBAR_MT_editor_menus"
+    bl_label = ""
+
+    def draw(self, context):
+        self.draw_menus(self.layout, context)
+
+    @staticmethod
+    def draw_menus(layout, context):
+        layout.menu("TOPBAR_MT_file")
+
+        layout.menu("TOPBAR_MT_render")
+
+        layout.menu("TOPBAR_MT_window")
+        layout.menu("TOPBAR_MT_help")
+
+
+class TOPBAR_MT_file(Menu):
+    bl_label = "File"
+
+    def draw(self, context):
+        layout = self.layout
+
+        layout.operator_context = 'INVOKE_AREA'
+        layout.operator("wm.read_homefile", text="New", icon='NEW')
+        layout.operator("wm.open_mainfile", text="Open...", icon='FILE_FOLDER')
+        layout.menu("TOPBAR_MT_file_open_recent", icon='OPEN_RECENT')
+        layout.operator("wm.revert_mainfile", icon='FILE_REFRESH')
+        layout.operator("wm.recover_last_session", icon='RECOVER_LAST')
+        layout.operator("wm.recover_auto_save", text="Recover Auto Save...", icon='RECOVER_AUTO')
+
+        layout.separator()
+
+        layout.operator_context = 'EXEC_AREA' if context.blend_data.is_saved else 'INVOKE_AREA'
+        layout.operator("wm.save_mainfile", text="Save", icon='FILE_TICK')
+
+        layout.operator_context = 'INVOKE_AREA'
+        layout.operator("wm.save_as_mainfile", text="Save As...", icon='SAVE_AS')
+        layout.operator_context = 'INVOKE_AREA'
+        layout.operator("wm.save_as_mainfile", text="Save Copy...", icon='SAVE_COPY').copy = True
+
+        layout.separator()
+
+        layout.operator("screen.userpref_show", text="User Preferences...", icon='PREFERENCES')
+
+        layout.operator_context = 'INVOKE_AREA'
+        layout.operator("wm.save_homefile", icon='SAVE_PREFS')
+        layout.operator("wm.read_factory_settings", icon='LOAD_FACTORY')
+
+        layout.separator()
+
+        layout.operator_context = 'INVOKE_AREA'
+        layout.operator("wm.link", text="Link", icon='LINK_BLEND')
+        layout.operator("wm.append", text="Append", icon='APPEND_BLEND')
+        layout.menu("TOPBAR_MT_file_previews")
+
+        layout.separator()
+
+        layout.menu("TOPBAR_MT_file_import", icon='IMPORT')
+        layout.menu("TOPBAR_MT_file_export", icon='EXPORT')
+
+        layout.separator()
+
+        layout.menu("TOPBAR_MT_file_external_data", icon='EXTERNAL_DATA')
+
+        layout.separator()
+
+        layout.operator_context = 'EXEC_AREA'
+        if bpy.data.is_dirty and context.user_preferences.view.use_quit_dialog:
+            layout.operator_context = 'INVOKE_SCREEN'  # quit dialog
+        layout.operator("wm.quit_blender", text="Quit", icon='QUIT')
+
+
+class TOPBAR_MT_file_import(Menu):
+    bl_idname = "TOPBAR_MT_file_import"
+    bl_label = "Import"
+
+    def draw(self, context):
+        if bpy.app.build_options.collada:
+            self.layout.operator("wm.collada_import", text="Collada (Default) (.dae)")
+        if bpy.app.build_options.alembic:
+            self.layout.operator("wm.alembic_import", text="Alembic (.abc)")
+
+
+class TOPBAR_MT_file_export(Menu):
+    bl_idname = "TOPBAR_MT_file_export"
+    bl_label = "Export"
+
+    def draw(self, context):
+        if bpy.app.build_options.collada:
+            self.layout.operator("wm.collada_export", text="Collada (Default) (.dae)")
+        if bpy.app.build_options.alembic:
+            self.layout.operator("wm.alembic_export", text="Alembic (.abc)")
+
+
+class TOPBAR_MT_file_external_data(Menu):
+    bl_label = "External Data"
+
+    def draw(self, context):
+        layout = self.layout
+
+        icon = 'CHECKBOX_HLT' if bpy.data.use_autopack else 'CHECKBOX_DEHLT'
+        layout.operator("file.autopack_toggle", icon=icon)
+
+        layout.separator()
+
+        pack_all = layout.row()
+        pack_all.operator("file.pack_all")
+        pack_all.active = not bpy.data.use_autopack
+
+        unpack_all = layout.row()
+        unpack_all.operator("file.unpack_all")
+        unpack_all.active = not bpy.data.use_autopack
+
+        layout.separator()
+
+        layout.operator("file.make_paths_relative")
+        layout.operator("file.make_paths_absolute")
+        layout.operator("file.report_missing_files")
+        layout.operator("file.find_missing_files")
+
+
+class TOPBAR_MT_file_previews(Menu):
+    bl_label = "Data Previews"
+
+    def draw(self, context):
+        layout = self.layout
+
+        layout.operator("wm.previews_ensure")
+        layout.operator("wm.previews_batch_generate")
+
+        layout.separator()
+
+        layout.operator("wm.previews_clear")
+        layout.operator("wm.previews_batch_clear")
+
+
+class TOPBAR_MT_game(Menu):
+    bl_label = "Game"
+
+    def draw(self, context):
+        layout = self.layout
+
+        gs = context.scene.game_settings
+
+        layout.operator("view3d.game_start")
+
+        layout.separator()
+
+        layout.prop(gs, "show_debug_properties")
+        layout.prop(gs, "show_framerate_profile")
+        layout.prop(gs, "show_physics_visualization")
+        layout.prop(gs, "use_deprecation_warnings")
+        layout.prop(gs, "use_animation_record")
+        layout.separator()
+        layout.prop(gs, "use_auto_start")
+
+
+class TOPBAR_MT_render(Menu):
+    bl_label = "Render"
+
+    def draw(self, context):
+        layout = self.layout
+
+        layout.operator("render.render", text="Render Image", icon='RENDER_STILL').use_viewport = True
+        props = layout.operator("render.render", text="Render Animation", icon='RENDER_ANIMATION')
+        props.animation = True
+        props.use_viewport = True
+
+        layout.separator()
+
+        layout.operator("render.opengl", text="OpenGL Render Image")
+        layout.operator("render.opengl", text="OpenGL Render Animation").animation = True
+        layout.menu("TOPBAR_MT_opengl_render")
+
+        layout.separator()
+
+        layout.operator("render.view_show")
+        layout.operator("render.play_rendered_anim", icon='PLAY')
+
+
+class TOPBAR_MT_opengl_render(Menu):
+    bl_label = "OpenGL Render Options"
+
+    def draw(self, context):
+        layout = self.layout
+
+        rd = context.scene.render
+        layout.prop(rd, "use_antialiasing")
+        layout.prop(rd, "use_full_sample")
+
+        layout.prop_menu_enum(rd, "antialiasing_samples")
+        layout.prop_menu_enum(rd, "alpha_mode")
+
+
+class TOPBAR_MT_window(Menu):
+    bl_label = "Window"
+
+    def draw(self, context):
+        import sys
+
+        layout = self.layout
+
+        layout.operator("wm.window_new")
+        layout.operator("wm.window_fullscreen_toggle", icon='FULLSCREEN_ENTER')
+
+        layout.separator()
+
+        layout.operator("screen.screenshot")
+        layout.operator("screen.screencast")
+
+        if sys.platform[:3] == "win":
+            layout.separator()
+            layout.operator("wm.console_toggle", icon='CONSOLE')
+
+        if context.scene.render.use_multiview:
+            layout.separator()
+            layout.operator("wm.set_stereo_3d", icon='CAMERA_STEREO')
+
+
+class TOPBAR_MT_help(Menu):
+    bl_label = "Help"
+
+    def draw(self, context):
+        layout = self.layout
+
+        layout.operator(
+                "wm.url_open", text="Manual", icon='HELP',
+                ).url = "https://docs.blender.org/manual/en/dev/"
+        layout.operator(
+                "wm.url_open", text="Release Log", icon='URL',
+                ).url = "http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/%d.%d" % bpy.app.version[:2]
+        layout.separator()
+
+        layout.operator(
+                "wm.url_open", text="Blender Website", icon='URL',
+                ).url = "https://www.blender.org"
+        layout.operator(
+                "wm.url_open", text="Blender Store", icon='URL',
+                ).url = "https://store.blender.org"
+        layout.operator(
+                "wm.url_open", text="Developer Community", icon='URL',
+                ).url = "https://www.blender.org/get-involved/"
+        layout.operator(
+                "wm.url_open", text="User Community", icon='URL',
+                ).url = "https://www.blender.org/support/user-community"
+        layout.separator()
+        layout.operator(
+                "wm.url_open", text="Report a Bug", icon='URL',
+                ).url = "https://developer.blender.org/maniphest/task/edit/form/1"
+        layout.separator()
+
+        layout.operator(
+                "wm.url_open", text="Python API Reference", icon='URL',
+                ).url = bpy.types.WM_OT_doc_view._prefix
+
+        layout.operator("wm.operator_cheat_sheet", icon='TEXT')
+        layout.operator("wm.sysinfo", icon='TEXT')
+        layout.separator()
+
+        layout.operator("wm.splash", icon='BLENDER')
+
+
+classes = (
+    TOPBAR_HT_upper_bar,
+    TOPBAR_HT_lower_bar,
+    TOPBAR_MT_editor_menus,
+    TOPBAR_MT_file,
+    TOPBAR_MT_file_import,
+    TOPBAR_MT_file_export,
+    TOPBAR_MT_file_external_data,
+    TOPBAR_MT_file_previews,
+    TOPBAR_MT_game,
+    TOPBAR_MT_render,
+    TOPBAR_MT_opengl_render,
+    TOPBAR_MT_window,
+    TOPBAR_MT_help,
+)
+
+if __name__ == "__main__":  # only for live edit.
+    from bpy.utils import register_class
+    for cls in classes:
+        register_class(cls)
diff --git a/release/scripts/startup/bl_ui/space_userpref.py b/release/scripts/startup/bl_ui/space_userpref.py
index 953ebba54ca..9afda6b77bf 100644
--- a/release/scripts/startup/bl_ui/space_userpref.py
+++ b/release/scripts/startup/bl_ui/space_userpref.py
@@ -853,6 +853,9 @@ class USERPREF_PT_theme(Panel):
             col.label(text="List Item:")
             self._theme_widget_style(col, ui.wcol_list_item)
 
+            col.label(text="Tab:")
+            self._theme_widget_style(col, ui.wcol_tab)
+
             ui_state = theme.user_interface.wcol_state
             col.label(text="State:")