UI: Initial persistent floating redo panel

This is the first step to moving redo out of the top-bar, see: T55039

- Support for floating panels in the ScrArea has been added.
- A new region type RGN_TYPE_HUD is used for floating settings input.
- Only one HUD should be visible at a time.
- Currently HUD regions are only visible
  for 3D view and image space types.
- There are currently some remaining glitches with hide/show
  that need further investigation.

1 files changed, 276 insertions, 0 deletions

diff --git a/source/blender/editors/interface/interface_region_hud.c b/source/blender/editors/interface/interface_region_hud.c
new file mode 100644
index 00000000000..ad779d2580f
--- /dev/null
+++ b/source/blender/editors/interface/interface_region_hud.c
@@ -0,0 +1,276 @@
+/*
+ * ***** 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_hud.c
+ *  \ingroup edinterface
+ *
+ * Floating Persistent Region
+ */
+
+#include <string.h>
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_userdef_types.h"
+
+#include "BLI_string.h"
+#include "BLI_rect.h"
+#include "BLI_listbase.h"
+#include "BLI_utildefines.h"
+
+#include "BKE_context.h"
+#include "BKE_screen.h"
+#include "BKE_main.h"
+
+#include "WM_api.h"
+#include "WM_types.h"
+
+#include "RNA_access.h"
+
+#include "BIF_gl.h"
+
+#include "UI_interface.h"
+#include "UI_view2d.h"
+
+#include "BLT_translation.h"
+
+#include "ED_screen.h"
+#include "ED_undo.h"
+
+#include "interface_intern.h"
+
+
+/* -------------------------------------------------------------------- */
+/** \name Utilities
+ * \{ */
+
+static bool last_redo_poll(const bContext *C)
+{
+	wmOperator *op = WM_operator_last_redo(C);
+	if (op == NULL) {
+		return false;
+	}
+	bool success = false;
+	if (!WM_operator_check_ui_empty(op->type)) {
+		success = WM_operator_poll((bContext *)C, op->type);
+	}
+	return success;
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Redo Panel
+ * \{ */
+
+static int hud_panel_operator_redo_poll(const bContext *C, PanelType *UNUSED(pt))
+{
+	return last_redo_poll(C);
+}
+
+static void hud_panel_operator_redo_draw_header(const bContext *C, Panel *pa)
+{
+	wmOperator *op = WM_operator_last_redo(C);
+	BLI_strncpy(pa->drawname, RNA_struct_ui_name(op->type->srna), sizeof(pa->drawname));
+}
+
+static void hud_panel_operator_redo_draw(const bContext *C, Panel *pa)
+{
+	wmOperator *op = WM_operator_last_redo(C);
+	if (op == NULL) {
+		return;
+	}
+	if (!WM_operator_check_ui_enabled(C, op->type->name)) {
+		uiLayoutSetEnabled(pa->layout, false);
+	}
+	uiLayout *col = uiLayoutColumn(pa->layout, false);
+	uiTemplateOperatorRedoProperties(col, C);
+}
+
+static void hud_panels_register(ARegionType *art, int space_type, int region_type)
+{
+	PanelType *pt;
+
+	pt = MEM_callocN(sizeof(PanelType), __func__);
+	strcpy(pt->idname, "OPERATOR_PT_redo");
+	strcpy(pt->label, N_("Redo"));
+	strcpy(pt->translation_context, BLT_I18NCONTEXT_DEFAULT_BPYRNA);
+	pt->draw_header = hud_panel_operator_redo_draw_header;
+	pt->draw = hud_panel_operator_redo_draw;
+	pt->poll = hud_panel_operator_redo_poll;
+	pt->space_type = space_type;
+	pt->region_type = region_type;
+	BLI_addtail(&art->paneltypes, pt);
+}
+
+/** \} */
+
+/* -------------------------------------------------------------------- */
+/** \name Callbacks for Floating Region
+ * \{ */
+
+static void hud_region_init(wmWindowManager *wm, ARegion *ar)
+{
+	ED_region_panels_init(wm, ar);
+	UI_region_handlers_add(&ar->handlers);
+}
+
+static void hud_region_layout(const bContext *C, ARegion *ar)
+{
+	if (!last_redo_poll(C)) {
+		ED_region_tag_redraw(ar);
+		ar->flag |= RGN_FLAG_HIDDEN;
+		return;
+	}
+
+	int size_y = ar->sizey;
+
+	ED_region_panels_layout_ex(C, ar, NULL, -1, true);
+
+	if (ar->panels.first && (ar->sizey != size_y)) {
+		View2D *v2d = &ar->v2d;
+		ar->winx = ar->sizex;
+		ar->winy = ar->sizey;
+
+		ar->winrct.xmax = (ar->winrct.xmin + ar->winx) - 1;
+		ar->winrct.ymax = (ar->winrct.ymin + ar->winy) - 1;
+
+		UI_view2d_region_reinit(v2d, V2D_COMMONVIEW_PANELS_UI, ar->winx, ar->winy);
+	}
+
+	/* restore view matrix */
+	UI_view2d_view_restore(C);
+}
+
+static void hud_region_draw(const bContext *C, ARegion *ar)
+{
+	UI_view2d_view_ortho(&ar->v2d);
+	wmOrtho2_region_pixelspace(ar);
+	glClearColor(0, 0, 0, 0.0f);
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	if ((ar->flag & RGN_FLAG_HIDDEN) == 0) {
+		ui_draw_widget_back(UI_WTYPE_BOX, false, &(rcti){.xmax = ar->winx, .ymax = ar->winy});
+		ED_region_panels_draw(C, ar);
+	}
+}
+
+ARegionType *ED_area_type_hud(int space_type)
+{
+	ARegionType *art = MEM_callocN(sizeof(ARegionType), __func__);
+	art->regionid = RGN_TYPE_HUD;
+	art->keymapflag = ED_KEYMAP_UI | ED_KEYMAP_VIEW2D;
+	art->layout = hud_region_layout;
+	art->draw = hud_region_draw;
+	art->init = hud_region_init;
+
+	hud_panels_register(art, space_type, art->regionid);
+
+	art->lock = 1;   /* can become flag, see BKE_spacedata_draw_locks */
+	return art;
+}
+
+static ARegion *hud_region_add(ScrArea *sa)
+{
+	ARegion *ar = MEM_callocN(sizeof(ARegion), "area region");
+	ARegion *ar_win = BKE_area_find_region_type(sa, RGN_TYPE_WINDOW);
+	if (ar_win) {
+		BLI_insertlinkbefore(&sa->regionbase, ar_win, ar);
+	}
+	else {
+		BLI_addtail(&sa->regionbase, ar);
+	}
+	ar->regiontype = RGN_TYPE_HUD;
+	ar->alignment = RGN_ALIGN_FLOAT;
+	ar->overlap = true;
+	ar->flag |= RGN_FLAG_DYNAMIC_SIZE;
+
+	return ar;
+}
+
+void ED_area_type_hud_ensure(bContext *C, ScrArea *sa)
+{
+	/* We only want one at a time. */
+	Main *bmain = CTX_data_main(C);
+	for (wmWindowManager *wm = bmain->wm.first; wm; wm = wm->id.next) {
+		for (wmWindow *win = wm->windows.first; win; win = win->next) {
+			bScreen *screen = WM_window_get_active_screen(win);
+			for (ScrArea *sa_iter = screen->areabase.first; sa_iter; sa_iter = sa_iter->next) {
+				if (sa != sa_iter) {
+					for (ARegion *ar = sa_iter->regionbase.first; ar; ar = ar->next) {
+						if (ar->regiontype == RGN_TYPE_HUD) {
+							if ((ar->flag & RGN_FLAG_HIDDEN) == 0) {
+								ar->flag |= RGN_FLAG_HIDDEN;
+								ED_region_tag_redraw(ar);
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+
+	ARegionType *art = BKE_regiontype_from_id(sa->type, RGN_TYPE_HUD);
+	if (art == NULL) {
+		return;
+	}
+
+	bool init = false;
+	ARegion *ar = BKE_area_find_region_type(sa, RGN_TYPE_HUD);
+	if (!last_redo_poll(C)) {
+		if (ar) {
+			ar->flag |= RGN_FLAG_HIDDEN;
+		}
+		return;
+	}
+
+	if (ar == NULL) {
+		init = true;
+		ar = hud_region_add(sa);
+		ar->type = art;
+	}
+
+	ED_region_init(ar);
+	ED_region_tag_redraw(ar);
+
+	/* Let 'ED_area_update_region_sizes' do the work of placing the region.
+	 * Otherwise we could set the 'ar->winrct' & 'ar->winx/winy' here. */
+	if (init) {
+		sa->flag |= AREA_FLAG_REGION_SIZE_UPDATE;
+	}
+	else {
+		if (ar->flag & RGN_FLAG_HIDDEN) {
+			sa->flag |= AREA_FLAG_REGION_SIZE_UPDATE;
+		}
+		ar->flag &= ~RGN_FLAG_HIDDEN;
+
+	}
+
+	/* We shouldn't need to do this every time :S */
+	/* XXX, this is evil! - it also makes the menu show on first draw. :( */
+	hud_region_layout(C, ar);
+}
+
+/** \} */