UI: Initial popover support for panels

- UILayout.popover(.. panel_type ..)
  A single panel
- UILayout.popover_group(.. panel categories ..)
  Expands all panels matching args.

Currently used in the topbar for redo and paint options.

1 files changed, 283 insertions, 0 deletions

diff --git a/source/blender/editors/interface/interface_region_popover.c b/source/blender/editors/interface/interface_region_popover.c
new file mode 100644
index 00000000000..035efb368a6
--- /dev/null
+++ b/source/blender/editors/interface/interface_region_popover.c
@@ -0,0 +1,283 @@
+/*
+ * ***** 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.
+ *
+ * The Original Code is Copyright (C) 2008 Blender Foundation.
+ * All rights reserved.
+ *
+ * Contributor(s): Blender Foundation
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/editors/interface/interface_region_popover.c
+ *  \ingroup edinterface
+ *
+ * Pop-Over Region
+ *
+ * \note This is very close to 'interface_region_menu_popup.c'
+ *
+ * We could even merge them, however menu logic is already over-loaded.
+ * PopOver's have the following differences.
+ *
+ * - UI is not constrained to a list.
+ * - Pressing a button won't close the pop-over.
+ * - Different draw style (to show this is has different behavior from a menu).
+ * - #PanelType are used insetead of #MenuType.
+ * - No menu flipping support.
+ * - No moving the menu to fit the mouse cursor.
+ * - No key accelerators to access menu items
+ *   (if we add support they would work differently).
+ * - No arrow key navigation.
+ * - No menu memory.
+ * - No title.
+ */
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_userdef_types.h"
+
+#include "BLI_math.h"
+#include "BLI_listbase.h"
+
+#include "BLI_string.h"
+#include "BLI_rect.h"
+#include "BLI_utildefines.h"
+#include "BLI_ghash.h"
+
+#include "BKE_context.h"
+#include "BKE_screen.h"
+#include "BKE_report.h"
+
+#include "WM_api.h"
+#include "WM_types.h"
+
+#include "RNA_access.h"
+
+#include "UI_interface.h"
+
+#include "BLT_translation.h"
+
+#include "ED_screen.h"
+
+#include "interface_intern.h"
+#include "interface_regions_intern.h"
+
+/* -------------------------------------------------------------------- */
+/** \name Popup Menu with Callback or String
+ * \{ */
+
+struct uiPopover {
+	uiBlock *block;
+	uiLayout *layout;
+	uiBut *but;
+	ARegion *butregion;
+
+	int mx, my;
+	bool popover, slideout;
+
+	uiMenuCreateFunc menu_func;
+	void *menu_arg;
+};
+
+static uiBlock *ui_block_func_POPOVER(bContext *C, uiPopupBlockHandle *handle, void *arg_pup)
+{
+	uiBlock *block;
+	uiPopover *pup = arg_pup;
+	int offset[2], minwidth, width, height;
+
+	if (pup->menu_func) {
+		pup->block->handle = handle;
+		pup->menu_func(C, pup->layout, pup->menu_arg);
+		pup->block->handle = NULL;
+	}
+
+	if (pup->but) {
+		/* minimum width to enforece */
+		minwidth = BLI_rctf_size_x(&pup->but->rect);
+	}
+	else {
+		minwidth = 50;
+	}
+
+	block = pup->block;
+
+	/* in some cases we create the block before the region,
+	 * so we set it delayed here if necessary */
+	if (BLI_findindex(&handle->region->uiblocks, block) == -1)
+		UI_block_region_set(block, handle->region);
+
+	block->direction = UI_DIR_DOWN;
+
+	UI_block_layout_resolve(block, &width, &height);
+
+	UI_block_flag_enable(block, UI_BLOCK_MOVEMOUSE_QUIT | UI_BLOCK_KEEP_OPEN);
+
+	if (pup->popover) {
+		UI_block_flag_enable(block, UI_BLOCK_LOOP);
+		UI_block_direction_set(block, block->direction);
+		block->minbounds = minwidth;
+		UI_block_bounds_set_popup(block, 1, offset[0], offset[1]);
+	}
+	else {
+		/* for a header menu we set the direction automatic */
+		block->minbounds = minwidth;
+		UI_block_bounds_set_normal(block, 1);
+	}
+
+	/* if menu slides out of other menu, override direction */
+	if (pup->slideout)
+		UI_block_direction_set(block, UI_DIR_RIGHT);
+
+	return pup->block;
+}
+
+uiPopupBlockHandle *ui_popover_panel_create(
+        bContext *C, ARegion *butregion, uiBut *but,
+        uiMenuCreateFunc menu_func, void *arg)
+{
+	wmWindow *window = CTX_wm_window(C);
+	uiStyle *style = UI_style_get_dpi();
+	uiPopupBlockHandle *handle;
+	uiPopover *pup;
+
+	pup = MEM_callocN(sizeof(uiPopover), __func__);
+	pup->block = UI_block_begin(C, NULL, __func__, UI_EMBOSS);
+	UI_block_emboss_set(pup->block, UI_EMBOSS);
+	pup->layout = UI_block_layout(pup->block, UI_LAYOUT_VERTICAL, UI_LAYOUT_PANEL, 0, 0, 200, 0, MENU_PADDING, style);
+	pup->slideout = false; // but ? ui_block_is_menu(but->block) : false;
+	pup->but = but;
+	uiLayoutSetOperatorContext(pup->layout, WM_OP_INVOKE_REGION_WIN);
+
+	if (!but) {
+		/* no button to start from, means we are a popover */
+		pup->mx = window->eventstate->x;
+		pup->my = window->eventstate->y;
+		pup->popover = true;
+		pup->block->flag |= UI_BLOCK_NO_FLIP;
+	}
+	/* some enums reversing is strange, currently we have no good way to
+	 * reverse some enum's but not others, so reverse all so the first menu
+	 * items are always close to the mouse cursor */
+	else {
+		if (but->context)
+			uiLayoutContextCopy(pup->layout, but->context);
+	}
+
+	/* menu is created from a callback */
+	pup->menu_func = menu_func;
+	pup->menu_arg = arg;
+
+	handle = ui_popup_block_create(C, butregion, but, NULL, ui_block_func_POPOVER, pup);
+
+	if (!but) {
+		handle->popup = true;
+
+		UI_popup_handlers_add(C, &window->modalhandlers, handle, 0);
+		WM_event_add_mousemove(C);
+	}
+
+	handle->can_refresh = false;
+	MEM_freeN(pup);
+
+	return handle;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Popup Menu API with begin & end
+ * \{ */
+
+/**
+ * Only return handler, and set optional title.
+ * \param block_name: Assigned to uiBlock.name (useful info for debugging).
+ */
+uiPopover *UI_popover_begin_ex(bContext *C, const char *block_name)
+{
+	uiStyle *style = UI_style_get_dpi();
+	uiPopover *pup = MEM_callocN(sizeof(uiPopover), "popover menu");
+
+	pup->block = UI_block_begin(C, NULL, block_name, UI_EMBOSS);
+	pup->layout = UI_block_layout(pup->block, UI_LAYOUT_VERTICAL, UI_LAYOUT_PANEL, 0, 0, 200, 0, MENU_PADDING, style);
+
+	/* Copied from menus, change if needed. */
+	uiLayoutSetOperatorContext(pup->layout, WM_OP_EXEC_REGION_WIN);
+
+	/* create in advance so we can let buttons point to retval already */
+	pup->block->handle = MEM_callocN(sizeof(uiPopupBlockHandle), "uiPopupBlockHandle");
+
+	return pup;
+}
+
+uiPopover *UI_popover_begin(bContext *C)
+{
+	return UI_popover_begin_ex(C, __func__);
+}
+
+/**
+ * Setting the button makes the popover open from the button instead of the cursor.
+ */
+#if 0
+void UI_popover_panel_but_set(uiPopover *pup, struct ARegion *butregion, uiBut *but)
+{
+	pup->but = but;
+	pup->butregion = butregion;
+}
+#endif
+
+/* set the whole structure to work */
+void UI_popover_end(bContext *C, uiPopover *pup)
+{
+	wmWindow *window = CTX_wm_window(C);
+	uiPopupBlockHandle *menu;
+	uiBut *but = NULL;
+	ARegion *butregion = NULL;
+
+	pup->popover = true;
+	pup->mx = window->eventstate->x;
+	pup->my = window->eventstate->y;
+
+	if (pup->but) {
+		but = pup->but;
+		butregion = pup->butregion;
+	}
+
+	menu = ui_popup_block_create(C, butregion, but, NULL, ui_block_func_POPOVER, pup);
+	menu->popup = true;
+
+	UI_popup_handlers_add(C, &window->modalhandlers, menu, 0);
+	WM_event_add_mousemove(C);
+
+	menu->can_refresh = false;
+	MEM_freeN(pup);
+}
+
+uiLayout *UI_popover_layout(uiPopover *pup)
+{
+	return pup->layout;
+}
+
+/** \} */
+
+/* We may want to support this in futurew */
+/* Similar to UI_popup_menu_invoke */
+// int UI_popover_panel_invoke(bContext *C, const char *idname, ReportList *reports);