/*
 * ***** 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) 2004 Blender Foundation.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): Joshua Leung
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/editors/space_outliner/outliner_draw.c
 *  \ingroup spoutliner
 */

#include "DNA_anim_types.h"
#include "DNA_armature_types.h"
#include "DNA_collection_types.h"
#include "DNA_gpencil_types.h"
#include "DNA_gpencil_modifier_types.h"
#include "DNA_lamp_types.h"
#include "DNA_lightprobe_types.h"
#include "DNA_object_types.h"
#include "DNA_scene_types.h"
#include "DNA_sequence_types.h"

#include "BLI_math.h"
#include "BLI_blenlib.h"
#include "BLI_string_utils.h"
#include "BLI_utildefines.h"
#include "BLI_mempool.h"

#include "BLT_translation.h"

#include "BKE_context.h"
#include "BKE_deform.h"
#include "BKE_fcurve.h"
#include "BKE_gpencil.h"
#include "BKE_global.h"
#include "BKE_idcode.h"
#include "BKE_layer.h"
#include "BKE_library.h"
#include "BKE_main.h"
#include "BKE_modifier.h"
#include "BKE_report.h"
#include "BKE_scene.h"
#include "BKE_object.h"

#include "DEG_depsgraph.h"
#include "DEG_depsgraph_build.h"

#include "ED_armature.h"
#include "ED_keyframing.h"
#include "ED_object.h"
#include "ED_screen.h"

#include "WM_api.h"
#include "WM_types.h"

#include "GPU_immediate.h"
#include "GPU_state.h"

#include "UI_interface.h"
#include "UI_interface_icons.h"
#include "UI_resources.h"
#include "UI_view2d.h"

#include "RNA_access.h"

#include "outliner_intern.h"

/* disable - this is far too slow - campbell */
// #define USE_GROUP_SELECT

/* ****************************************************** */
/* Tree Size Functions */

static void outliner_height(SpaceOops *soops, ListBase *lb, int *h)
{
	TreeElement *te = lb->first;
	while (te) {
		TreeStoreElem *tselem = TREESTORE(te);
		if (TSELEM_OPEN(tselem, soops)) {
			outliner_height(soops, &te->subtree, h);
		}
		(*h) += UI_UNIT_Y;
		te = te->next;
	}
}

#if 0  // XXX this is currently disabled until te->xend is set correctly
static void outliner_width(SpaceOops *soops, ListBase *lb, int *w)
{
	TreeElement *te = lb->first;
	while (te) {
//		TreeStoreElem *tselem = TREESTORE(te);

		// XXX fixme... te->xend is not set yet
		if (!TSELEM_OPEN(tselem, soops)) {
			if (te->xend > *w)
				*w = te->xend;
		}
		outliner_width(soops, &te->subtree, w);
		te = te->next;
	}
}
#endif

static void outliner_rna_width(SpaceOops *soops, ListBase *lb, int *w, int startx)
{
	TreeElement *te = lb->first;
	while (te) {
		TreeStoreElem *tselem = TREESTORE(te);
		// XXX fixme... (currently, we're using a fixed length of 100)!
#if 0
		if (te->xend) {
			if (te->xend > *w)
				*w = te->xend;
		}
#endif
		if (startx + 100 > *w)
			*w = startx + 100;

		if (TSELEM_OPEN(tselem, soops)) {
			outliner_rna_width(soops, &te->subtree, w, startx + UI_UNIT_X);
		}
		te = te->next;
	}
}

/**
 * The active object is only needed for reference.
 */
static bool is_object_data_in_editmode(const ID *id, const Object *obact)
{
	const short id_type = GS(id->name);
	return (
	        (obact && (obact->mode & OB_MODE_EDIT)) &&
	        (id && OB_DATA_SUPPORT_EDITMODE(id_type)) &&
	        (GS(((ID *)obact->data)->name) == id_type) &&
	        BKE_object_data_is_in_editmode(id)
	);
}

/* ****************************************************** */

static void restrictbutton_recursive_ebone(bContext *C, EditBone *ebone_parent, int flag, bool set_flag)
{
	Object *obedit = CTX_data_edit_object(C);
	bArmature *arm = obedit->data;
	EditBone *ebone;

	for (ebone = arm->edbo->first; ebone; ebone = ebone->next) {
		if (ED_armature_ebone_is_child_recursive(ebone_parent, ebone)) {
			if (set_flag) {
				ebone->flag &= ~(BONE_TIPSEL | BONE_SELECTED | BONE_ROOTSEL);
				ebone->flag |= flag;
			}
			else {
				ebone->flag &= ~flag;
			}
		}
	}
}

static void restrictbutton_recursive_bone(Bone *bone_parent, int flag, bool set_flag)
{
	Bone *bone;
	for (bone = bone_parent->childbase.first; bone; bone = bone->next) {
		if (set_flag) {
			bone->flag &= ~(BONE_TIPSEL | BONE_SELECTED | BONE_ROOTSEL);
			bone->flag |= flag;
		}
		else {
			bone->flag &= ~flag;
		}
		restrictbutton_recursive_bone(bone, flag, set_flag);
	}

}

static void restrictbutton_r_lay_cb(bContext *C, void *poin, void *UNUSED(poin2))
{
	WM_event_add_notifier(C, NC_SCENE | ND_RENDER_OPTIONS, poin);
}

static void restrictbutton_modifier_cb(bContext *C, void *UNUSED(poin), void *poin2)
{
	Object *ob = (Object *)poin2;

	DEG_id_tag_update(&ob->id, OB_RECALC_DATA);
	WM_event_add_notifier(C, NC_OBJECT | ND_MODIFIER, ob);
}

static void restrictbutton_bone_visibility_cb(bContext *C, void *UNUSED(poin), void *poin2)
{
	Bone *bone = (Bone *)poin2;
	if (bone->flag & BONE_HIDDEN_P)
		bone->flag &= ~(BONE_SELECTED | BONE_TIPSEL | BONE_ROOTSEL);

	if (CTX_wm_window(C)->eventstate->ctrl) {
		restrictbutton_recursive_bone(bone, BONE_HIDDEN_P, (bone->flag & BONE_HIDDEN_P) != 0);
	}

	WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
}

static void restrictbutton_bone_select_cb(bContext *C, void *UNUSED(poin), void *poin2)
{
	Bone *bone = (Bone *)poin2;
	if (bone->flag & BONE_UNSELECTABLE)
		bone->flag &= ~(BONE_SELECTED | BONE_TIPSEL | BONE_ROOTSEL);

	if (CTX_wm_window(C)->eventstate->ctrl) {
		restrictbutton_recursive_bone(bone, BONE_UNSELECTABLE, (bone->flag & BONE_UNSELECTABLE) != 0);
	}

	WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
}

static void restrictbutton_ebone_select_cb(bContext *C, void *UNUSED(poin), void *poin2)
{
	EditBone *ebone = (EditBone *)poin2;

	if (ebone->flag & BONE_UNSELECTABLE) {
		ebone->flag &= ~(BONE_SELECTED | BONE_TIPSEL | BONE_ROOTSEL);
	}

	if (CTX_wm_window(C)->eventstate->ctrl) {
		restrictbutton_recursive_ebone(C, ebone, BONE_UNSELECTABLE, (ebone->flag & BONE_UNSELECTABLE) != 0);
	}

	WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
}

static void restrictbutton_ebone_visibility_cb(bContext *C, void *UNUSED(poin), void *poin2)
{
	EditBone *ebone = (EditBone *)poin2;
	if (ebone->flag & BONE_HIDDEN_A) {
		ebone->flag &= ~(BONE_SELECTED | BONE_TIPSEL | BONE_ROOTSEL);
	}

	if (CTX_wm_window(C)->eventstate->ctrl) {
		restrictbutton_recursive_ebone(C, ebone, BONE_HIDDEN_A, (ebone->flag & BONE_HIDDEN_A) != 0);
	}

	WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
}

static void restrictbutton_gp_layer_flag_cb(bContext *C, void *UNUSED(poin), void *UNUSED(poin2))
{
	WM_event_add_notifier(C, NC_GPENCIL | ND_DATA | NA_EDITED, NULL);
}

static void restrictbutton_id_user_toggle(bContext *UNUSED(C), void *poin, void *UNUSED(poin2))
{
	ID *id = (ID *)poin;

	BLI_assert(id != NULL);

	if (id->flag & LIB_FAKEUSER) {
		id_us_plus(id);
	}
	else {
		id_us_min(id);
	}
}

static void hidebutton_base_flag_cb(bContext *C, void *poin, void *poin2)
{
	Scene *scene = CTX_data_scene(C);
	ViewLayer *view_layer = poin;
	Base *base = poin2;
	bool extend = (CTX_wm_window(C)->eventstate->ctrl == 0);

	/* Undo button toggle, let function do it. */
	base->flag ^= BASE_HIDDEN;

	BKE_base_set_visible(scene, view_layer, base, extend);

	if (!extend && (base->flag & BASE_VISIBLE)) {
		/* Auto select solo-ed object. */
		ED_object_base_select(base, BA_SELECT);
		view_layer->basact = base;
	}

	DEG_id_tag_update(&scene->id, DEG_TAG_BASE_FLAGS_UPDATE);
	WM_event_add_notifier(C, NC_SCENE | ND_OB_SELECT, scene);
}

static void hidebutton_layer_collection_flag_cb(bContext *C, void *poin, void *poin2)
{
	Scene *scene = CTX_data_scene(C);
	ViewLayer *view_layer = poin;
	LayerCollection *lc = poin2;
	bool extend = (CTX_wm_window(C)->eventstate->ctrl == 0);

	/* Undo button toggle, let function do it. */
	lc->runtime_flag ^= LAYER_COLLECTION_HAS_VISIBLE_OBJECTS;

	BKE_layer_collection_set_visible(scene, view_layer, lc, extend);

	DEG_id_tag_update(&scene->id, DEG_TAG_BASE_FLAGS_UPDATE);
	WM_event_add_notifier(C, NC_SCENE | ND_OB_SELECT, scene);
}

static void namebutton_cb(bContext *C, void *tsep, char *oldname)
{
	Main *bmain = CTX_data_main(C);
	SpaceOops *soops = CTX_wm_space_outliner(C);
	Object *obedit = CTX_data_edit_object(C);
	BLI_mempool *ts = soops->treestore;
	TreeStoreElem *tselem = tsep;

	if (ts && tselem) {
		TreeElement *te = outliner_find_tree_element(&soops->tree, tselem);

		if (tselem->type == 0) {
			BLI_libblock_ensure_unique_name(bmain, tselem->id->name);

			switch (GS(tselem->id->name)) {
				case ID_MA:
					WM_event_add_notifier(C, NC_MATERIAL, NULL); break;
				case ID_TE:
					WM_event_add_notifier(C, NC_TEXTURE, NULL); break;
				case ID_IM:
					WM_event_add_notifier(C, NC_IMAGE, NULL); break;
				case ID_SCE:
					WM_event_add_notifier(C, NC_SCENE, NULL); break;
				default:
					WM_event_add_notifier(C, NC_ID | NA_RENAME, NULL); break;
			}
			/* Check the library target exists */
			if (te->idcode == ID_LI) {
				Library *lib = (Library *)tselem->id;
				char expanded[FILE_MAX];

				BKE_library_filepath_set(bmain, lib, lib->name);

				BLI_strncpy(expanded, lib->name, sizeof(expanded));
				BLI_path_abs(expanded, BKE_main_blendfile_path(bmain));
				if (!BLI_exists(expanded)) {
					BKE_reportf(CTX_wm_reports(C), RPT_ERROR,
					            "Library path '%s' does not exist, correct this before saving", expanded);
				}
				else if (lib->id.tag & LIB_TAG_MISSING) {
					BKE_reportf(CTX_wm_reports(C), RPT_INFO,
					            "Library path '%s' is now valid, please reload the library", expanded);
					lib->id.tag &= ~LIB_TAG_MISSING;
				}
			}
		}
		else {
			switch (tselem->type) {
				case TSE_DEFGROUP:
					defgroup_unique_name(te->directdata, (Object *)tselem->id); //	id = object
					break;
				case TSE_NLA_ACTION:
					BLI_libblock_ensure_unique_name(bmain, tselem->id->name);
					break;
				case TSE_EBONE:
				{
					bArmature *arm = (bArmature *)tselem->id;
					if (arm->edbo) {
						EditBone *ebone = te->directdata;
						char newname[sizeof(ebone->name)];

						/* restore bone name */
						BLI_strncpy(newname, ebone->name, sizeof(ebone->name));
						BLI_strncpy(ebone->name, oldname, sizeof(ebone->name));
						ED_armature_bone_rename(bmain, obedit->data, oldname, newname);
						WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
					}
					break;
				}

				case TSE_BONE:
				{
					ViewLayer *view_layer = CTX_data_view_layer(C);
					Scene *scene = CTX_data_scene(C);
					bArmature *arm = (bArmature *)tselem->id;
					Bone *bone = te->directdata;
					char newname[sizeof(bone->name)];

					/* always make current object active */
					tree_element_active(C, scene, view_layer, soops, te, OL_SETSEL_NORMAL, true);

					/* restore bone name */
					BLI_strncpy(newname, bone->name, sizeof(bone->name));
					BLI_strncpy(bone->name, oldname, sizeof(bone->name));
					ED_armature_bone_rename(bmain, arm, oldname, newname);
					WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
					break;
				}
				case TSE_POSE_CHANNEL:
				{
					Scene *scene = CTX_data_scene(C);
					ViewLayer *view_layer = CTX_data_view_layer(C);
					Object *ob = (Object *)tselem->id;
					bPoseChannel *pchan = te->directdata;
					char newname[sizeof(pchan->name)];

					/* always make current pose-bone active */
					tree_element_active(C, scene, view_layer, soops, te, OL_SETSEL_NORMAL, true);

					BLI_assert(ob->type == OB_ARMATURE);

					/* restore bone name */
					BLI_strncpy(newname, pchan->name, sizeof(pchan->name));
					BLI_strncpy(pchan->name, oldname, sizeof(pchan->name));
					ED_armature_bone_rename(bmain, ob->data, oldname, newname);
					WM_event_add_notifier(C, NC_OBJECT | ND_POSE, NULL);
					break;
				}
				case TSE_POSEGRP:
				{
					Object *ob = (Object *)tselem->id; // id = object
					bActionGroup *grp = te->directdata;

					BLI_uniquename(&ob->pose->agroups, grp, CTX_DATA_(BLT_I18NCONTEXT_ID_ACTION, "Group"), '.',
					               offsetof(bActionGroup, name), sizeof(grp->name));
					WM_event_add_notifier(C, NC_OBJECT | ND_POSE, ob);
					break;
				}
				case TSE_GP_LAYER:
				{
					bGPdata *gpd = (bGPdata *)tselem->id; /* id = GP Datablock */
					bGPDlayer *gpl = te->directdata;

					/* always make layer active */
					BKE_gpencil_layer_setactive(gpd, gpl);

					// XXX: name needs translation stuff
					BLI_uniquename(&gpd->layers, gpl, "GP Layer", '.',
					               offsetof(bGPDlayer, info), sizeof(gpl->info));

					WM_event_add_notifier(C, NC_GPENCIL | ND_DATA, gpd);
					break;
				}
				case TSE_R_LAYER:
				{
					Scene *scene = (Scene *)tselem->id;
					ViewLayer *view_layer = te->directdata;

					/* Restore old name. */
					char newname[sizeof(view_layer->name)];
					BLI_strncpy(newname, view_layer->name, sizeof(view_layer->name));
					BLI_strncpy(view_layer->name, oldname, sizeof(view_layer->name));

					/* Rename, preserving animation and compositing data. */
					BKE_view_layer_rename(bmain, scene, view_layer, newname);
					WM_event_add_notifier(C, NC_ID | NA_RENAME, NULL);
					break;
				}
				case TSE_LAYER_COLLECTION:
				{
					BLI_libblock_ensure_unique_name(bmain, tselem->id->name);
					WM_event_add_notifier(C, NC_ID | NA_RENAME, NULL);
					break;
				}
			}
		}
		tselem->flag &= ~TSE_TEXTBUT;
	}
}

static void outliner_draw_restrictbuts(
        uiBlock *block, Scene *scene, ViewLayer *view_layer, ARegion *ar, SpaceOops *soops, ListBase *lb)
{
	uiBut *bt;

	/* get RNA properties (once for speed) */
	PropertyRNA *object_prop_hide_viewport, *object_prop_hide_select, *object_prop_hide_render;
	PropertyRNA *collection_prop_hide_viewport, *collection_prop_hide_select, *collection_prop_hide_render;

	object_prop_hide_viewport = RNA_struct_type_find_property(&RNA_Object, "hide_viewport");
	object_prop_hide_select = RNA_struct_type_find_property(&RNA_Object, "hide_select");
	object_prop_hide_render = RNA_struct_type_find_property(&RNA_Object, "hide_render");
	collection_prop_hide_select = RNA_struct_type_find_property(&RNA_Collection, "hide_select");
	collection_prop_hide_viewport = RNA_struct_type_find_property(&RNA_Collection, "hide_viewport");
	collection_prop_hide_render = RNA_struct_type_find_property(&RNA_Collection, "hide_render");

	BLI_assert(object_prop_hide_viewport &&
	           object_prop_hide_select &&
	           object_prop_hide_render &&
	           collection_prop_hide_viewport &&
	           collection_prop_hide_select &&
	           collection_prop_hide_render);

	for (TreeElement *te = lb->first; te; te = te->next) {
		TreeStoreElem *tselem = TREESTORE(te);
		if (te->ys + 2 * UI_UNIT_Y >= ar->v2d.cur.ymin && te->ys <= ar->v2d.cur.ymax) {
			if (tselem->type == TSE_R_LAYER && (soops->outlinevis == SO_SCENES)) {
				/* View layer render toggle. */
				ViewLayer *layer = te->directdata;

				bt = uiDefIconButBitS(
				        block, UI_BTYPE_ICON_TOGGLE_N, VIEW_LAYER_RENDER, 0, ICON_RESTRICT_RENDER_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &layer->flag, 0, 0, 0, 0, TIP_("Use view layer for rendering"));
				UI_but_func_set(bt, restrictbutton_r_lay_cb, tselem->id, NULL);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
			}
			else if (tselem->type == 0 && te->idcode == ID_OB) {
				Object *ob = (Object *)tselem->id;
				Base *base = BKE_view_layer_base_find(view_layer, ob);

				if (base) {
					bt = uiDefIconButBitS(
					        block, UI_BTYPE_ICON_TOGGLE, BASE_HIDDEN, 0, ICON_HIDE_OFF,
					        (int)(ar->v2d.cur.xmax - OL_TOG_HIDEX), te->ys, UI_UNIT_X,
					        UI_UNIT_Y, &base->flag, 0, 0, 0, 0,
					        TIP_("Hide object in viewport (Ctrl to isolate)"));
					UI_but_func_set(bt, hidebutton_base_flag_cb, view_layer, base);
					UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
				}

				PointerRNA ptr;
				RNA_pointer_create((ID *)ob, &RNA_Object, ob, &ptr);

				bt = uiDefIconButR_prop(block, UI_BTYPE_ICON_TOGGLE, 0, ICON_RESTRICT_VIEW_OFF,
				                        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X, UI_UNIT_Y,
				                        &ptr, object_prop_hide_viewport, -1, 0, 0, -1, -1,
				                        TIP_("Restrict viewport visibility"));
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				bt = uiDefIconButR_prop(block, UI_BTYPE_ICON_TOGGLE, 0, ICON_RESTRICT_SELECT_OFF,
				                        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), te->ys, UI_UNIT_X, UI_UNIT_Y,
				                        &ptr, object_prop_hide_select, -1, 0, 0, -1, -1,
				                        TIP_("Restrict viewport selection"));
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				bt = uiDefIconButR_prop(block, UI_BTYPE_ICON_TOGGLE, 0, ICON_RESTRICT_RENDER_OFF,
				                        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), te->ys, UI_UNIT_X, UI_UNIT_Y,
				                        &ptr, object_prop_hide_render, -1, 0, 0, -1, -1,
				                        TIP_("Restrict render visibility"));
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

			}
			else if (tselem->type == TSE_MODIFIER) {
				ModifierData *md = (ModifierData *)te->directdata;
				Object *ob = (Object *)tselem->id;

				bt = uiDefIconButBitI(
				        block, UI_BTYPE_ICON_TOGGLE_N, eModifierMode_Realtime, 0, ICON_RESTRICT_VIEW_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &(md->mode), 0, 0, 0, 0,
				        TIP_("Restrict/Allow visibility in the 3D View"));
				UI_but_func_set(bt, restrictbutton_modifier_cb, scene, ob);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				bt = uiDefIconButBitI(
				        block, UI_BTYPE_ICON_TOGGLE_N, eModifierMode_Render, 0, ICON_RESTRICT_RENDER_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &(md->mode), 0, 0, 0, 0, TIP_("Restrict/Allow renderability"));
				UI_but_func_set(bt, restrictbutton_modifier_cb, scene, ob);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
			}
			else if (tselem->type == TSE_POSE_CHANNEL) {
				bPoseChannel *pchan = (bPoseChannel *)te->directdata;
				Bone *bone = pchan->bone;
				Object *ob = (Object *)tselem->id;

				bt = uiDefIconButBitI(
				        block, UI_BTYPE_ICON_TOGGLE, BONE_HIDDEN_P, 0, ICON_HIDE_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &(bone->flag), 0, 0, 0, 0,
				        TIP_("Restrict/Allow visibility in the 3D View"));
				UI_but_func_set(bt, restrictbutton_bone_visibility_cb, ob->data, bone);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				bt = uiDefIconButBitI(
				        block, UI_BTYPE_ICON_TOGGLE, BONE_UNSELECTABLE, 0, ICON_RESTRICT_SELECT_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &(bone->flag), 0, 0, 0, 0,
				        TIP_("Restrict/Allow selection in the 3D View"));
				UI_but_func_set(bt, restrictbutton_bone_select_cb, ob->data, bone);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
			}
			else if (tselem->type == TSE_EBONE) {
				EditBone *ebone = (EditBone *)te->directdata;

				bt = uiDefIconButBitI(
				        block, UI_BTYPE_ICON_TOGGLE, BONE_HIDDEN_A, 0, ICON_RESTRICT_VIEW_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &(ebone->flag), 0, 0, 0, 0,
				        TIP_("Restrict/Allow visibility in the 3D View"));
				UI_but_func_set(bt, restrictbutton_ebone_visibility_cb, NULL, ebone);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				bt = uiDefIconButBitI(
				        block, UI_BTYPE_ICON_TOGGLE, BONE_UNSELECTABLE, 0, ICON_RESTRICT_SELECT_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &(ebone->flag), 0, 0, 0, 0,
				        TIP_("Restrict/Allow selection in the 3D View"));
				UI_but_func_set(bt, restrictbutton_ebone_select_cb, NULL, ebone);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
			}
			else if (tselem->type == TSE_GP_LAYER) {
				bGPDlayer *gpl = (bGPDlayer *)te->directdata;

				bt = uiDefIconButBitS(
				        block, UI_BTYPE_ICON_TOGGLE, GP_LAYER_HIDE, 0, ICON_HIDE_OFF,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &gpl->flag, 0, 0, 0, 0,
				        TIP_("Restrict/Allow visibility in the 3D View"));
				UI_but_func_set(bt, restrictbutton_gp_layer_flag_cb, NULL, gpl);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				bt = uiDefIconButBitS(
				        block, UI_BTYPE_ICON_TOGGLE, GP_LAYER_LOCKED, 0, ICON_UNLOCKED,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), te->ys, UI_UNIT_X,
				        UI_UNIT_Y, &gpl->flag, 0, 0, 0, 0,
				        TIP_("Restrict/Allow editing of strokes and keyframes in this layer"));
				UI_but_func_set(bt, restrictbutton_gp_layer_flag_cb, NULL, gpl);
				UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

				/* TODO: visibility in renders */
			}
			else if (outliner_is_collection_tree_element(te)) {
				LayerCollection *lc = (tselem->type == TSE_LAYER_COLLECTION) ? te->directdata : NULL;
				Collection *collection = outliner_collection_from_tree_element(te);

				if ((!lc || !(lc->flag & LAYER_COLLECTION_EXCLUDE)) &&
				    !(collection->flag & COLLECTION_IS_MASTER))
				{
					if (lc && (lc->runtime_flag & LAYER_COLLECTION_HAS_ENABLED_OBJECTS)) {
						bt = uiDefIconButBitS(
						        block, UI_BTYPE_ICON_TOGGLE_N, LAYER_COLLECTION_HAS_VISIBLE_OBJECTS, 0, ICON_HIDE_OFF,
						        (int)(ar->v2d.cur.xmax - OL_TOG_HIDEX), te->ys, UI_UNIT_X,
						        UI_UNIT_Y, &lc->runtime_flag, 0, 0, 0, 0,
						        TIP_("Hide collection in viewport (Ctrl to isolate)"));
						UI_but_func_set(bt, hidebutton_layer_collection_flag_cb, view_layer, lc);
						UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
					}

					PointerRNA collection_ptr;
					RNA_id_pointer_create(&collection->id, &collection_ptr);

					bt = uiDefIconButR_prop(
					        block, UI_BTYPE_ICON_TOGGLE, 0, ICON_RESTRICT_VIEW_OFF,
					        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X,
					        UI_UNIT_Y, &collection_ptr, collection_prop_hide_viewport, -1, 0, 0, 0, 0, NULL);
					UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

					bt = uiDefIconButR_prop(
					        block, UI_BTYPE_ICON_TOGGLE, 0, ICON_RESTRICT_RENDER_OFF,
					        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), te->ys, UI_UNIT_X,
					        UI_UNIT_Y, &collection_ptr, collection_prop_hide_render, -1, 0, 0, 0, 0, NULL);
					UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);

					bt = uiDefIconButR_prop(
					        block, UI_BTYPE_ICON_TOGGLE, 0, ICON_RESTRICT_SELECT_OFF,
					        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), te->ys, UI_UNIT_X,
					        UI_UNIT_Y, &collection_ptr, collection_prop_hide_select, -1, 0, 0, 0, 0, NULL);
					UI_but_flag_enable(bt, UI_BUT_DRAG_LOCK);
				}
			}
		}

		if (TSELEM_OPEN(tselem, soops)) {
			outliner_draw_restrictbuts(block, scene, view_layer, ar, soops, &te->subtree);
		}
	}
}

static void outliner_draw_userbuts(uiBlock *block, ARegion *ar, SpaceOops *soops, ListBase *lb)
{

	for (TreeElement *te = lb->first; te; te = te->next) {
		TreeStoreElem *tselem = TREESTORE(te);
		if (te->ys + 2 * UI_UNIT_Y >= ar->v2d.cur.ymin && te->ys <= ar->v2d.cur.ymax) {
			if (tselem->type == 0) {
				uiBut *bt;
				ID *id = tselem->id;
				const char *tip = NULL;
				int icon = ICON_NONE;
				char buf[16] = "";
				int but_flag = UI_BUT_DRAG_LOCK;

				if (ID_IS_LINKED(id))
					but_flag |= UI_BUT_DISABLED;

				if (id->flag & LIB_FAKEUSER) {
					icon = ICON_FILE_TICK;
					tip  = TIP_("Data-block will be retained using a fake user");
				}
				else {
					icon = ICON_X;
					tip  = TIP_("Data-block has no users and will be deleted");
				}
				bt = uiDefIconButBitS(
				        block, UI_BTYPE_TOGGLE, LIB_FAKEUSER, 1, icon,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), te->ys, UI_UNIT_X, UI_UNIT_Y,
				        &id->flag, 0, 0, 0, 0, tip);
				UI_but_func_set(bt, restrictbutton_id_user_toggle, id, NULL);
				UI_but_flag_enable(bt, but_flag);


				BLI_str_format_int_grouped(buf, id->us);
				bt = uiDefBut(
				        block, UI_BTYPE_BUT, 1, buf,
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), te->ys,
				        UI_UNIT_X, UI_UNIT_Y, NULL, 0.0, 0.0, 0, 0,
				        TIP_("Number of users of this data-block"));
				UI_but_flag_enable(bt, but_flag);


				bt = uiDefButBitS(
				        block, UI_BTYPE_TOGGLE, LIB_FAKEUSER, 1, (id->flag & LIB_FAKEUSER) ? "F" : " ",
				        (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), te->ys, UI_UNIT_X, UI_UNIT_Y,
				        &id->flag, 0, 0, 0, 0,
				        TIP_("Data-block has a 'fake' user which will keep it in the file "
				             "even if nothing else uses it"));
				UI_but_func_set(bt, restrictbutton_id_user_toggle, id, NULL);
				UI_but_flag_enable(bt, but_flag);
			}
		}

		if (TSELEM_OPEN(tselem, soops)) {
			outliner_draw_userbuts(block, ar, soops, &te->subtree);
		}
	}
}

static void outliner_draw_rnacols(ARegion *ar, int sizex)
{
	View2D *v2d = &ar->v2d;

	float miny = v2d->cur.ymin;
	if (miny < v2d->tot.ymin) miny = v2d->tot.ymin;

	GPU_line_width(1.0f);

	uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
	immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
	immUniformThemeColorShadeAlpha(TH_BACK, -15, -200);

	immBegin(GPU_PRIM_LINES, 4);

	immVertex2f(pos, sizex, v2d->cur.ymax);
	immVertex2f(pos, sizex, miny);

	immVertex2f(pos, sizex + OL_RNA_COL_SIZEX, v2d->cur.ymax);
	immVertex2f(pos, sizex + OL_RNA_COL_SIZEX, miny);

	immEnd();

	immUnbindProgram();
}

static void outliner_draw_rnabuts(uiBlock *block, ARegion *ar, SpaceOops *soops, int sizex, ListBase *lb)
{
	PointerRNA *ptr;
	PropertyRNA *prop;

	for (TreeElement *te = lb->first; te; te = te->next) {
		TreeStoreElem *tselem = TREESTORE(te);
		if (te->ys + 2 * UI_UNIT_Y >= ar->v2d.cur.ymin && te->ys <= ar->v2d.cur.ymax) {
			if (tselem->type == TSE_RNA_PROPERTY) {
				ptr = &te->rnaptr;
				prop = te->directdata;

				if (!TSELEM_OPEN(tselem, soops)) {
					if (RNA_property_type(prop) == PROP_POINTER) {
						uiBut *but = uiDefAutoButR(
						        block, ptr, prop, -1, "", ICON_NONE, sizex, te->ys,
						        OL_RNA_COL_SIZEX, UI_UNIT_Y - 1);
						UI_but_flag_enable(but, UI_BUT_DISABLED);
					}
					else if (RNA_property_type(prop) == PROP_ENUM) {
						uiDefAutoButR(
						        block, ptr, prop, -1, NULL, ICON_NONE, sizex, te->ys, OL_RNA_COL_SIZEX,
						        UI_UNIT_Y - 1);
					}
					else {
						uiDefAutoButR(
						        block, ptr, prop, -1, "", ICON_NONE, sizex, te->ys, OL_RNA_COL_SIZEX,
						        UI_UNIT_Y - 1);
					}
				}
			}
			else if (tselem->type == TSE_RNA_ARRAY_ELEM) {
				ptr = &te->rnaptr;
				prop = te->directdata;

				uiDefAutoButR(
				        block, ptr, prop, te->index, "", ICON_NONE, sizex, te->ys, OL_RNA_COL_SIZEX,
				        UI_UNIT_Y - 1);
			}
		}

		if (TSELEM_OPEN(tselem, soops)) {
			outliner_draw_rnabuts(block, ar, soops, sizex, &te->subtree);
		}
	}
}

static void outliner_buttons(const bContext *C, uiBlock *block, ARegion *ar, TreeElement *te)
{
	uiBut *bt;
	TreeStoreElem *tselem;
	int spx, dx, len;

	tselem = TREESTORE(te);

	BLI_assert(tselem->flag & TSE_TEXTBUT);
	/* If we add support to rename Sequence.
	 * need change this.
	 */

	if (tselem->type == TSE_EBONE) len = sizeof(((EditBone *) 0)->name);
	else if (tselem->type == TSE_MODIFIER) len = sizeof(((ModifierData *) 0)->name);
	else if (tselem->id && GS(tselem->id->name) == ID_LI) len = sizeof(((Library *) 0)->name);
	else len = MAX_ID_NAME - 2;

	spx = te->xs + 1.8f * UI_UNIT_X;
	dx = ar->v2d.cur.xmax - (spx + 3.2f * UI_UNIT_X);

	bt = uiDefBut(
	        block, UI_BTYPE_TEXT, OL_NAMEBUTTON, "", spx, te->ys, dx, UI_UNIT_Y - 1, (void *)te->name,
	        1.0, (float)len, 0, 0, "");
	UI_but_func_rename_set(bt, namebutton_cb, tselem);

	/* returns false if button got removed */
	if (false == UI_but_active_only(C, ar, block, bt)) {
		tselem->flag &= ~TSE_TEXTBUT;

		/* bad! (notifier within draw) without this, we don't get a refresh */
		WM_event_add_notifier(C, NC_SPACE | ND_SPACE_OUTLINER, NULL);
	}
}

/* ****************************************************** */
/* Normal Drawing... */

TreeElementIcon tree_element_get_icon(TreeStoreElem *tselem, TreeElement *te)
{
	TreeElementIcon data = {0};

	if (tselem->type) {
		switch (tselem->type) {
			case TSE_ANIM_DATA:
				data.icon = ICON_ANIM_DATA; /* XXX */
				break;
			case TSE_NLA:
				data.icon = ICON_NLA;
				break;
			case TSE_NLA_TRACK:
				data.icon = ICON_NLA; /* XXX */
				break;
			case TSE_NLA_ACTION:
				data.icon = ICON_ACTION;
				break;
			case TSE_DRIVER_BASE:
				data.icon = ICON_DRIVER;
				break;
			case TSE_DEFGROUP_BASE:
				data.icon = ICON_GROUP_VERTEX;
				break;
			case TSE_BONE:
			case TSE_EBONE:
				data.icon = ICON_BONE_DATA;
				break;
			case TSE_CONSTRAINT_BASE:
				data.icon = ICON_CONSTRAINT;
				break;
			case TSE_MODIFIER_BASE:
				data.icon = ICON_MODIFIER;
				break;
			case TSE_LINKED_OB:
				data.icon = ICON_OBJECT_DATA;
				break;
			case TSE_LINKED_PSYS:
				data.icon = ICON_PARTICLES;
				break;
			case TSE_MODIFIER:
			{
				Object *ob = (Object *)tselem->id;
				if (ob->type != OB_GPENCIL) {
					ModifierData *md = BLI_findlink(&ob->modifiers, tselem->nr);
					switch ((ModifierType)md->type) {
						case eModifierType_Subsurf:
							data.icon = ICON_MOD_SUBSURF;
							break;
						case eModifierType_Armature:
							data.icon = ICON_MOD_ARMATURE;
							break;
						case eModifierType_Lattice:
							data.icon = ICON_MOD_LATTICE;
							break;
						case eModifierType_Curve:
							data.icon = ICON_MOD_CURVE;
							break;
						case eModifierType_Build:
							data.icon = ICON_MOD_BUILD;
							break;
						case eModifierType_Mirror:
							data.icon = ICON_MOD_MIRROR;
							break;
						case eModifierType_Decimate:
							data.icon = ICON_MOD_DECIM;
							break;
						case eModifierType_Wave:
							data.icon = ICON_MOD_WAVE;
							break;
						case eModifierType_Hook:
							data.icon = ICON_HOOK;
							break;
						case eModifierType_Softbody:
							data.icon = ICON_MOD_SOFT;
							break;
						case eModifierType_Boolean:
							data.icon = ICON_MOD_BOOLEAN;
							break;
						case eModifierType_ParticleSystem:
							data.icon = ICON_MOD_PARTICLES;
							break;
						case eModifierType_ParticleInstance:
							data.icon = ICON_MOD_PARTICLES;
							break;
						case eModifierType_EdgeSplit:
							data.icon = ICON_MOD_EDGESPLIT;
							break;
						case eModifierType_Array:
							data.icon = ICON_MOD_ARRAY;
							break;
						case eModifierType_UVProject:
						case eModifierType_UVWarp:  /* TODO, get own icon */
							data.icon = ICON_MOD_UVPROJECT;
							break;
						case eModifierType_Displace:
							data.icon = ICON_MOD_DISPLACE;
							break;
						case eModifierType_Shrinkwrap:
							data.icon = ICON_MOD_SHRINKWRAP;
							break;
						case eModifierType_Cast:
							data.icon = ICON_MOD_CAST;
							break;
						case eModifierType_MeshDeform:
						case eModifierType_SurfaceDeform:
							data.icon = ICON_MOD_MESHDEFORM;
							break;
						case eModifierType_Bevel:
							data.icon = ICON_MOD_BEVEL;
							break;
						case eModifierType_Smooth:
						case eModifierType_LaplacianSmooth:
						case eModifierType_CorrectiveSmooth:
							data.icon = ICON_MOD_SMOOTH;
							break;
						case eModifierType_SimpleDeform:
							data.icon = ICON_MOD_SIMPLEDEFORM;
							break;
						case eModifierType_Mask:
							data.icon = ICON_MOD_MASK;
							break;
						case eModifierType_Cloth:
							data.icon = ICON_MOD_CLOTH;
							break;
						case eModifierType_Explode:
							data.icon = ICON_MOD_EXPLODE;
							break;
						case eModifierType_Collision:
						case eModifierType_Surface:
							data.icon = ICON_MOD_PHYSICS;
							break;
						case eModifierType_Fluidsim:
							data.icon = ICON_MOD_FLUIDSIM;
							break;
						case eModifierType_Multires:
							data.icon = ICON_MOD_MULTIRES;
							break;
						case eModifierType_Smoke:
							data.icon = ICON_MOD_SMOKE;
							break;
						case eModifierType_Solidify:
							data.icon = ICON_MOD_SOLIDIFY;
							break;
						case eModifierType_Screw:
							data.icon = ICON_MOD_SCREW;
							break;
						case eModifierType_Remesh:
							data.icon = ICON_MOD_REMESH;
							break;
						case eModifierType_WeightVGEdit:
						case eModifierType_WeightVGMix:
						case eModifierType_WeightVGProximity:
							data.icon = ICON_MOD_VERTEX_WEIGHT;
							break;
						case eModifierType_DynamicPaint:
							data.icon = ICON_MOD_DYNAMICPAINT;
							break;
						case eModifierType_Ocean:
							data.icon = ICON_MOD_OCEAN;
							break;
						case eModifierType_Warp:
							data.icon = ICON_MOD_WARP;
							break;
						case eModifierType_Skin:
							data.icon = ICON_MOD_SKIN;
							break;
						case eModifierType_Triangulate:
							data.icon = ICON_MOD_TRIANGULATE;
							break;
						case eModifierType_MeshCache:
							data.icon = ICON_MOD_MESHDEFORM; /* XXX, needs own icon */
							break;
						case eModifierType_MeshSequenceCache:
							data.icon = ICON_MOD_MESHDEFORM; /* XXX, needs own icon */
							break;
						case eModifierType_Wireframe:
							data.icon = ICON_MOD_WIREFRAME;
							break;
						case eModifierType_LaplacianDeform:
							data.icon = ICON_MOD_MESHDEFORM; /* XXX, needs own icon */
							break;
						case eModifierType_DataTransfer:
							data.icon = ICON_MOD_DATA_TRANSFER;
							break;
						case eModifierType_NormalEdit:
						case eModifierType_WeightedNormal:
							data.icon = ICON_MOD_NORMALEDIT;
							break;
							/* Default */
						case eModifierType_None:
						case eModifierType_ShapeKey:

						case NUM_MODIFIER_TYPES:
							data.icon = ICON_DOT;
							break;
					}
				}
				else {
					/* grease pencil modifiers */
					GpencilModifierData *md = BLI_findlink(&ob->greasepencil_modifiers, tselem->nr);
					switch ((GpencilModifierType)md->type) {
						case eGpencilModifierType_Noise:
							data.icon = ICON_RNDCURVE;
							break;
						case eGpencilModifierType_Subdiv:
							data.icon = ICON_MOD_SUBSURF;
							break;
						case eGpencilModifierType_Thick:
							data.icon = ICON_MAN_ROT;
							break;
						case eGpencilModifierType_Tint:
							data.icon = ICON_COLOR;
							break;
						case eGpencilModifierType_Instance:
							data.icon = ICON_MOD_ARRAY;
							break;
						case eGpencilModifierType_Build:
							data.icon = ICON_MOD_BUILD;
							break;
						case eGpencilModifierType_Opacity:
							data.icon = ICON_MOD_MASK;
							break;
						case eGpencilModifierType_Color:
							data.icon = ICON_GROUP_VCOL;
							break;
						case eGpencilModifierType_Lattice:
							data.icon = ICON_MOD_LATTICE;
							break;
						case eGpencilModifierType_Mirror:
							data.icon = ICON_MOD_MIRROR;
							break;
						case eGpencilModifierType_Simplify:
							data.icon = ICON_MOD_DECIM;
							break;
						case eGpencilModifierType_Smooth:
							data.icon = ICON_MOD_SMOOTH;
							break;
						case eGpencilModifierType_Hook:
							data.icon = ICON_HOOK;
							break;
						case eGpencilModifierType_Offset:
							data.icon = ICON_MOD_DISPLACE;
							break;
						case eGpencilModifierType_Armature:
							data.icon = ICON_MOD_ARMATURE;
							break;

							/* Default */
						default:
							data.icon = ICON_DOT;
							break;
					}
				}
				break;
			}
			case TSE_POSE_BASE:
				data.icon = ICON_ARMATURE_DATA;
				break;
			case TSE_POSE_CHANNEL:
				data.icon = ICON_BONE_DATA;
				break;
			case TSE_PROXY:
				data.icon = ICON_GHOST;
				break;
			case TSE_R_LAYER_BASE:
				data.icon = ICON_RENDERLAYERS;
				break;
			case TSE_SCENE_OBJECTS_BASE:
				data.icon = ICON_OUTLINER_OB_GROUP_INSTANCE;
				break;
			case TSE_R_LAYER:
				data.icon = ICON_RENDER_RESULT;
				break;
			case TSE_LINKED_LAMP:
				data.icon = ICON_LIGHT_DATA;
				break;
			case TSE_LINKED_MAT:
				data.icon = ICON_MATERIAL_DATA;
				break;
			case TSE_POSEGRP_BASE:
				data.icon = ICON_GROUP_BONE;
				break;
			case TSE_SEQUENCE:
				if (te->idcode == SEQ_TYPE_MOVIE)
					data.icon = ICON_SEQUENCE;
				else if (te->idcode == SEQ_TYPE_META)
					data.icon = ICON_DOT;
				else if (te->idcode == SEQ_TYPE_SCENE)
					data.icon = ICON_SCENE;
				else if (te->idcode == SEQ_TYPE_SOUND_RAM)
					data.icon = ICON_SOUND;
				else if (te->idcode == SEQ_TYPE_IMAGE)
					data.icon = ICON_IMAGE;
				else
					data.icon = ICON_PARTICLES;
				break;
			case TSE_SEQ_STRIP:
				data.icon = ICON_LIBRARY_DATA_DIRECT;
				break;
			case TSE_SEQUENCE_DUP:
				data.icon = ICON_OBJECT_DATA;
				break;
			case TSE_RNA_STRUCT:
				if (RNA_struct_is_ID(te->rnaptr.type)) {
					data.drag_id = (ID *)te->rnaptr.data;
					data.icon = RNA_struct_ui_icon(te->rnaptr.type);
				}
				else {
					data.icon = RNA_struct_ui_icon(te->rnaptr.type);
				}
				break;
			case TSE_LAYER_COLLECTION:
			case TSE_SCENE_COLLECTION_BASE:
			case TSE_VIEW_COLLECTION_BASE:
			{
				Collection *collection = outliner_collection_from_tree_element(te);
				if (collection && !(collection->flag & COLLECTION_IS_MASTER)) {
					data.drag_id = tselem->id;
					data.drag_parent = (data.drag_id && te->parent) ? TREESTORE(te->parent)->id : NULL;
				}

				data.icon = ICON_GROUP;
				break;
			}
			/* Removed the icons from outliner. Need a better structure with Layers, Palettes and Colors */
			case TSE_GP_LAYER:
			{
				/* indicate whether layer is active */
				bGPDlayer *gpl = te->directdata;
				if (gpl->flag & GP_LAYER_ACTIVE) {
					data.icon = ICON_GREASEPENCIL;
				}
				else {
					data.icon = ICON_DOT;
				}
				break;
			}
			default:
				data.icon = ICON_DOT;
				break;
		}
	}
	else if (tselem->id) {
		data.drag_id = tselem->id;
		data.drag_parent = (data.drag_id && te->parent) ? TREESTORE(te->parent)->id : NULL;

		if (GS(tselem->id->name) == ID_OB) {
			Object *ob = (Object *)tselem->id;
			switch (ob->type) {
				case OB_LAMP:
					data.icon = ICON_OUTLINER_OB_LIGHT; break;
				case OB_MESH:
					data.icon = ICON_OUTLINER_OB_MESH; break;
				case OB_CAMERA:
					data.icon = ICON_OUTLINER_OB_CAMERA; break;
				case OB_CURVE:
					data.icon = ICON_OUTLINER_OB_CURVE; break;
				case OB_MBALL:
					data.icon = ICON_OUTLINER_OB_META; break;
				case OB_LATTICE:
					data.icon = ICON_OUTLINER_OB_LATTICE; break;
				case OB_ARMATURE:
					data.icon = ICON_OUTLINER_OB_ARMATURE; break;
				case OB_FONT:
					data.icon = ICON_OUTLINER_OB_FONT; break;
				case OB_SURF:
					data.icon = ICON_OUTLINER_OB_SURFACE; break;
				case OB_SPEAKER:
					data.icon = ICON_OUTLINER_OB_SPEAKER; break;
				case OB_LIGHTPROBE:
					data.icon = ICON_OUTLINER_OB_LIGHTPROBE; break;
				case OB_EMPTY:
					if (ob->dup_group) {
						data.icon = ICON_OUTLINER_OB_GROUP_INSTANCE;
					}
					else if (ob->empty_drawtype == OB_EMPTY_IMAGE) {
						data.icon = ICON_OUTLINER_OB_IMAGE;
					}
					else {
						data.icon = ICON_OUTLINER_OB_EMPTY;
					}
					break;
				case OB_GPENCIL:
					data.icon = ICON_OUTLINER_OB_GREASEPENCIL; break;
					break;
			}
		}
		else {
			/* TODO(sergey): Casting to short here just to handle ID_NLA which is
			 * NOT inside of IDType enum.
			 */
			switch ((short)GS(tselem->id->name)) {
				case ID_SCE:
					data.icon = ICON_SCENE_DATA; break;
				case ID_ME:
					data.icon = ICON_OUTLINER_DATA_MESH; break;
				case ID_CU:
					data.icon = ICON_OUTLINER_DATA_CURVE; break;
				case ID_MB:
					data.icon = ICON_OUTLINER_DATA_META; break;
				case ID_LT:
					data.icon = ICON_OUTLINER_DATA_LATTICE; break;
				case ID_LA:
				{
					Lamp *la = (Lamp *)tselem->id;
					switch (la->type) {
						case LA_LOCAL:
							data.icon = ICON_LIGHT_POINT; break;
						case LA_SUN:
							data.icon = ICON_LIGHT_SUN; break;
						case LA_SPOT:
							data.icon = ICON_LIGHT_SPOT; break;
						case LA_HEMI:
							data.icon = ICON_LIGHT_HEMI; break;
						case LA_AREA:
							data.icon = ICON_LIGHT_AREA; break;
						default:
							data.icon = ICON_OUTLINER_DATA_LIGHT; break;
					}
					break;
				}
				case ID_MA:
					data.icon = ICON_MATERIAL_DATA; break;
				case ID_TE:
					data.icon = ICON_TEXTURE_DATA; break;
				case ID_IM:
					data.icon = ICON_IMAGE_DATA; break;
				case ID_SPK:
				case ID_SO:
					data.icon = ICON_OUTLINER_DATA_SPEAKER; break;
				case ID_AR:
					data.icon = ICON_OUTLINER_DATA_ARMATURE; break;
				case ID_CA:
					data.icon = ICON_OUTLINER_DATA_CAMERA; break;
				case ID_KE:
					data.icon = ICON_SHAPEKEY_DATA; break;
				case ID_WO:
					data.icon = ICON_WORLD_DATA; break;
				case ID_AC:
					data.icon = ICON_ACTION; break;
				case ID_NLA:
					data.icon = ICON_NLA; break;
				case ID_TXT:
					data.icon = ICON_SCRIPT; break;
				case ID_GR:
					data.icon = ICON_GROUP; break;
				case ID_LI:
					if (tselem->id->tag & LIB_TAG_MISSING) {
						data.icon = ICON_LIBRARY_DATA_BROKEN;
					}
					else if (((Library *)tselem->id)->parent) {
						data.icon = ICON_LIBRARY_DATA_INDIRECT;
					}
					else {
						data.icon = ICON_LIBRARY_DATA_DIRECT;
					}
					break;
				case ID_LS:
					data.icon = ICON_LINE_DATA; break;
				case ID_GD:
					data.icon = ICON_OUTLINER_DATA_GREASEPENCIL; break;
				case ID_LP:
				{
					LightProbe *lp = (LightProbe *)tselem->id;
					switch (lp->type) {
						case LIGHTPROBE_TYPE_CUBE:
							data.icon = ICON_LIGHTPROBE_CUBEMAP; break;
						case LIGHTPROBE_TYPE_PLANAR:
							data.icon = ICON_LIGHTPROBE_PLANAR; break;
						case LIGHTPROBE_TYPE_GRID:
							data.icon = ICON_LIGHTPROBE_GRID; break;
						default:
							data.icon = ICON_LIGHTPROBE_CUBEMAP; break;
					}
					break;
				}
				case ID_BR:
					data.icon = ICON_BRUSH_DATA; break;
				case ID_SCR:
				case ID_WS:
					data.icon = ICON_WORKSPACE; break;
				default:
					break;
			}
		}
	}

	return data;
}

static void tselem_draw_icon(
        uiBlock *block, int xmax, float x, float y, TreeStoreElem *tselem, TreeElement *te,
        float alpha, const bool is_clickable)
{
	TreeElementIcon data = tree_element_get_icon(tselem, te);

	if (data.icon == 0) {
		return;
	}

	if (!is_clickable || x >= xmax) {
		/* placement of icons, copied from interface_widgets.c */
		float aspect = (0.8f * UI_UNIT_Y) / ICON_DEFAULT_HEIGHT;
		x += 2.0f * aspect;
		y += 2.0f * aspect;

		/* restrict column clip... it has been coded by simply overdrawing,
		 * doesn't work for buttons */
		UI_icon_draw_alpha(x, y, data.icon, alpha);
	}
	else {
		uiDefIconBut(
		        block, UI_BTYPE_LABEL, 0, data.icon, x, y, UI_UNIT_X, UI_UNIT_Y, NULL,
		        0.0, 0.0, 1.0, alpha,
		        (data.drag_id && ID_IS_LINKED(data.drag_id)) ? data.drag_id->lib->name : "");
	}
}

/**
 * For icon-only children of a collapsed tree,
 * Draw small number over the icon to show how many items of this type are displayed.
 */
static void outliner_draw_iconrow_number(
        const uiFontStyle *fstyle,
        int offsx, int ys,
        const int num_elements)
{
	float color[4] = {0.0f, 0.0f, 0.0f, 1.0f};
	float ufac = 0.25f * UI_UNIT_X;
	float offset_x = (float) offsx + UI_UNIT_X * 0.35f;

	UI_draw_roundbox_corner_set(UI_CNR_ALL);
	UI_draw_roundbox_aa(true,
	                    offset_x + ufac,
	                    (float)ys - UI_UNIT_Y * 0.2f + ufac,
	                    offset_x + UI_UNIT_X - ufac,
	                    (float)ys - UI_UNIT_Y * 0.2f + UI_UNIT_Y - ufac,
	                    (float)UI_UNIT_Y / 2.0f - ufac,
	                    color);

	/* Now the numbers. */
	unsigned char text_col[4];

	UI_GetThemeColor4ubv(TH_TEXT_HI, text_col);
	text_col[3] = 255;

	uiFontStyle fstyle_small = *fstyle;
	fstyle_small.points *= 0.8f;

	/* We treat +99 as 4 digits to make sure the (eyeballed) alignment looks nice. */
	int num_digits = 4;
	char number_text[4] = "+99\0";
	if (num_elements < 100) {
		BLI_snprintf(number_text, sizeof(number_text), "%d", num_elements);
		num_digits = num_elements < 10 ? 1 : 2;
	}
	UI_fontstyle_draw_simple(&fstyle_small,
	                         (offset_x + ufac + UI_UNIT_X * (2 - num_digits) * 0.12f),
	                         (float)ys - UI_UNIT_Y * 0.095f + ufac,
	                         number_text, text_col);
	UI_fontstyle_set(fstyle);
	GPU_blend(true); /* Roundbox and text drawing disables. */
}

static void outliner_draw_iconrow_doit(
        uiBlock *block, TreeElement *te,
        const uiFontStyle *fstyle,
        int xmax, int *offsx, int ys, float alpha_fac,
        const eOLDrawState active,
        const int num_elements)
{
	TreeStoreElem *tselem = TREESTORE(te);

	if (active != OL_DRAWSEL_NONE) {
		float ufac = UI_UNIT_X / 20.0f;
		float color[4] = {1.0f, 1.0f, 1.0f, 0.2f};

		UI_draw_roundbox_corner_set(UI_CNR_ALL);
		color[3] *= alpha_fac;

		UI_draw_roundbox_aa(true,
		                    (float) *offsx + 1.0f * ufac,
		                    (float)ys + 1.0f * ufac,
		                    (float)*offsx + UI_UNIT_X - 1.0f * ufac,
		                    (float)ys + UI_UNIT_Y - ufac,
		                    (float)UI_UNIT_Y / 2.0f - ufac,
		                    color);
		GPU_blend(true); /* Roundbox disables. */
	}

	/* No inlined icon should be clickable. */
	tselem_draw_icon(block, xmax, (float)*offsx, (float)ys, tselem, te, 0.8f * alpha_fac, false);
	te->xs = *offsx;
	te->ys = ys;
	te->xend = (short)*offsx + UI_UNIT_X;

	if (num_elements > 1) {
		outliner_draw_iconrow_number(fstyle, *offsx, ys, num_elements);
	}
	(*offsx) += UI_UNIT_X;
}

/**
 * Return the index to use based on the TreeElement ID and object type
 *
 * We use a continuum of indices until we get to the object datablocks
 * and we then make room for the object types.
 */
static int tree_element_id_type_to_index(TreeElement *te)
{
	TreeStoreElem *tselem = TREESTORE(te);

	const int id_index = tselem->type == 0 ? BKE_idcode_to_index(te->idcode) : INDEX_ID_GR;
	if (id_index < INDEX_ID_OB) {
		return id_index;
	}
	else if (id_index == INDEX_ID_OB) {
		const Object *ob = (Object *)tselem->id;
		return INDEX_ID_OB + ob->type;
	}
	else {
		return id_index + OB_TYPE_MAX;
	}
}

typedef struct MergedIconRow {
	eOLDrawState active[INDEX_ID_MAX + OB_TYPE_MAX];
	int num_elements[INDEX_ID_MAX + OB_TYPE_MAX];
	TreeElement *tree_element[INDEX_ID_MAX + OB_TYPE_MAX];
} MergedIconRow;

static void outliner_draw_iconrow(
        bContext *C, uiBlock *block, const uiFontStyle *fstyle, Scene *scene, ViewLayer *view_layer, SpaceOops *soops,
        ListBase *lb, int level, int xmax, int *offsx, int ys, float alpha_fac, MergedIconRow *merged)
{
	eOLDrawState active;
	const Object *obact = OBACT(view_layer);

	for (TreeElement *te = lb->first; te; te = te->next) {
		/* exit drawing early */
		if ((*offsx) - UI_UNIT_X > xmax)
			break;

		TreeStoreElem *tselem = TREESTORE(te);

		/* object hierarchy always, further constrained on level */
		if (level < 1 || (tselem->type == 0 && te->idcode == ID_OB)) {
			/* active blocks get white circle */
			if (tselem->type == 0) {
				if (te->idcode == ID_OB) {
					active = (OBACT(view_layer) == (Object *)tselem->id) ? OL_DRAWSEL_NORMAL : OL_DRAWSEL_NONE;
				}
				else if (is_object_data_in_editmode(tselem->id, obact)) {
					active = OL_DRAWSEL_NORMAL;
				}
				else {
					active = tree_element_active(C, scene, view_layer, soops, te, OL_SETSEL_NONE, false);
				}
			}
			else {
				active = tree_element_type_active(C, scene, view_layer, soops, te, tselem, OL_SETSEL_NONE, false);
			}

			if (!ELEM(tselem->type, 0, TSE_LAYER_COLLECTION)) {
				outliner_draw_iconrow_doit(block, te, fstyle, xmax, offsx, ys, alpha_fac, active, 1);
			}
			else {
				const int index = tree_element_id_type_to_index(te);
				merged->num_elements[index]++;
				if ((merged->tree_element[index] == NULL) ||
				    (active > merged->active[index]))
				{
					merged->tree_element[index] = te;
				}
				merged->active[index] = MAX2(active, merged->active[index]);
			}
		}

		/* this tree element always has same amount of branches, so don't draw */
		if (tselem->type != TSE_R_LAYER) {
			outliner_draw_iconrow(
			        C, block, fstyle, scene, view_layer, soops,
			        &te->subtree, level + 1, xmax, offsx, ys, alpha_fac, merged);
		}
	}

	if (level == 0) {
		for (int i = 0; i < INDEX_ID_MAX; i++) {
			const int num_subtypes = (i == INDEX_ID_OB) ? OB_TYPE_MAX : 1;
			/* See tree_element_id_type_to_index for the index logic. */
			int index_base = i;
			if (i > INDEX_ID_OB) {
				index_base += OB_TYPE_MAX;
			}
			for (int j = 0; j < num_subtypes; j++) {
				const int index = index_base + j;
				if (merged->num_elements[index] != 0) {
					outliner_draw_iconrow_doit(block,
					                           merged->tree_element[index],
					                           fstyle,
					                           xmax, offsx, ys, alpha_fac,
					                           merged->active[index],
					                           merged->num_elements[index]);
				}
			}
		}
	}
}

/* closed tree element */
static void outliner_set_coord_tree_element(TreeElement *te, int startx, int starty)
{
	TreeElement *ten;

	/* closed items may be displayed in row of parent, don't change their coordinate! */
	if ((te->flag & TE_ICONROW) == 0) {
		/* store coord and continue, we need coordinates for elements outside view too */
		te->xs = startx;
		te->ys = starty;
	}

	for (ten = te->subtree.first; ten; ten = ten->next) {
		outliner_set_coord_tree_element(ten, startx + UI_UNIT_X, starty);
	}
}


static void outliner_draw_tree_element(
        bContext *C, uiBlock *block, const uiFontStyle *fstyle, Scene *scene, ViewLayer *view_layer,
        ARegion *ar, SpaceOops *soops, TreeElement *te, bool draw_grayed_out,
        int startx, int *starty, TreeElement **te_edit)
{
	TreeStoreElem *tselem;
	float ufac = UI_UNIT_X / 20.0f;
	int offsx = 0;
	eOLDrawState active = OL_DRAWSEL_NONE;
	float color[4];
	tselem = TREESTORE(te);

	if (*starty + 2 * UI_UNIT_Y >= ar->v2d.cur.ymin && *starty <= ar->v2d.cur.ymax) {
		const float alpha_fac = ((te->flag & TE_DISABLED) || draw_grayed_out) ? 0.5f : 1.0f;
		const float alpha = 0.5f * alpha_fac;
		int xmax = ar->v2d.cur.xmax;

		if ((tselem->flag & TSE_TEXTBUT) && (*te_edit == NULL)) {
			*te_edit = te;
		}

		/* icons can be ui buts, we don't want it to overlap with restrict */
		if ((soops->flag & SO_HIDE_RESTRICTCOLS) == 0)
			xmax -= OL_TOGW + UI_UNIT_X;

		GPU_blend(true);

		/* colors for active/selected data */
		if (tselem->type == 0) {
			const Object *obact = OBACT(view_layer);
			if (te->idcode == ID_SCE) {
				if (tselem->id == (ID *)scene) {
					rgba_float_args_set(color, 1.0f, 1.0f, 1.0f, alpha);
					active = OL_DRAWSEL_ACTIVE;
				}
			}
			else if (te->idcode == ID_OB) {
				Object *ob = (Object *)tselem->id;
				Base *base = (Base *)te->directdata;
				const bool is_selected = (base != NULL) && ((base->flag & BASE_SELECTED) != 0);

				if (ob == obact || is_selected) {
					char col[4] = {0, 0, 0, 0};

					/* outliner active ob: always white text, circle color now similar to view3d */

					active = OL_DRAWSEL_ACTIVE;
					if (ob == obact) {
						if (is_selected) {
							UI_GetThemeColorType4ubv(TH_ACTIVE, SPACE_VIEW3D, col);
							col[3] = alpha;
						}

						active = OL_DRAWSEL_NORMAL;
					}
					else if (is_selected) {
						UI_GetThemeColorType4ubv(TH_SELECT, SPACE_VIEW3D, col);
						col[3] = alpha;
					}
					rgba_float_args_set(color, (float)col[0] / 255, (float)col[1] / 255, (float)col[2] / 255, alpha);
				}
			}
			else if (is_object_data_in_editmode(tselem->id, obact)) {
				rgba_float_args_set(color, 1.0f, 1.0f, 1.0f, alpha);
				active = OL_DRAWSEL_ACTIVE;
			}
			else {
				if (tree_element_active(C, scene, view_layer, soops, te, OL_SETSEL_NONE, false)) {
					rgba_float_args_set(color, 0.85f, 0.85f, 1.0f, alpha);
					active = OL_DRAWSEL_ACTIVE;
				}
			}
		}
		else {
			active = tree_element_type_active(C, scene, view_layer, soops, te, tselem, OL_SETSEL_NONE, false);
			rgba_float_args_set(color, 0.85f, 0.85f, 1.0f, alpha);
		}

		/* active circle */
		if (active != OL_DRAWSEL_NONE) {
			UI_draw_roundbox_corner_set(UI_CNR_ALL);
			UI_draw_roundbox_aa(
			        true,
			        (float)startx + UI_UNIT_X + 1.0f * ufac,
			        (float)*starty + 1.0f * ufac,
			        (float)startx + 2.0f * UI_UNIT_X - 1.0f * ufac,
			        (float)*starty + UI_UNIT_Y - 1.0f * ufac,
			        UI_UNIT_Y / 2.0f - 1.0f * ufac, color);
			GPU_blend(true); /* roundbox disables it */

			te->flag |= TE_ACTIVE; // for lookup in display hierarchies
		}

		if (tselem->type == TSE_VIEW_COLLECTION_BASE) {
			/* Scene collection in view layer can't expand/collapse. */
		}
		else if (te->subtree.first || (tselem->type == 0 && te->idcode == ID_SCE) || (te->flag & TE_LAZY_CLOSED)) {
			/* open/close icon, only when sublevels, except for scene */
			int icon_x = startx;

			// icons a bit higher
			if (TSELEM_OPEN(tselem, soops)) {
				UI_icon_draw_alpha(
				        (float)icon_x + 2 * ufac, (float)*starty + 1 * ufac, ICON_DISCLOSURE_TRI_DOWN,
				        alpha_fac);
			}
			else {
				UI_icon_draw_alpha(
				        (float)icon_x + 2 * ufac, (float)*starty + 1 * ufac, ICON_DISCLOSURE_TRI_RIGHT,
				        alpha_fac);
			}
		}
		offsx += UI_UNIT_X;

		/* datatype icon */

		if (!(ELEM(tselem->type, TSE_RNA_PROPERTY, TSE_RNA_ARRAY_ELEM, TSE_ID_BASE))) {
			tselem_draw_icon(block, xmax, (float)startx + offsx, (float)*starty, tselem, te, alpha_fac, true);
			offsx += UI_UNIT_X + 4 * ufac;
		}
		else
			offsx += 2 * ufac;

		if (ELEM(tselem->type, 0, TSE_LAYER_COLLECTION) && ID_IS_LINKED(tselem->id)) {
			if (tselem->id->tag & LIB_TAG_MISSING) {
				UI_icon_draw_alpha(
				        (float)startx + offsx + 2 * ufac, (float)*starty + 2 * ufac, ICON_LIBRARY_DATA_BROKEN,
				        alpha_fac);
			}
			else if (tselem->id->tag & LIB_TAG_INDIRECT) {
				UI_icon_draw_alpha(
				        (float)startx + offsx + 2 * ufac, (float)*starty + 2 * ufac, ICON_LIBRARY_DATA_INDIRECT,
				        alpha_fac);
			}
			else {
				UI_icon_draw_alpha(
				        (float)startx + offsx + 2 * ufac, (float)*starty + 2 * ufac, ICON_LIBRARY_DATA_DIRECT,
				        alpha_fac);
			}
			offsx += UI_UNIT_X + 4 * ufac;
		}
		else if (ELEM(tselem->type, 0, TSE_LAYER_COLLECTION) && ID_IS_STATIC_OVERRIDE(tselem->id)) {
			UI_icon_draw_alpha(
			        (float)startx + offsx + 2 * ufac, (float)*starty + 2 * ufac, ICON_LIBRARY_DATA_OVERRIDE,
			        alpha_fac);
			offsx += UI_UNIT_X + 4 * ufac;
		}
		GPU_blend(false);

		/* name */
		if ((tselem->flag & TSE_TEXTBUT) == 0) {
			unsigned char text_col[4];

			if (active == OL_DRAWSEL_NORMAL) {
				UI_GetThemeColor4ubv(TH_TEXT_HI, text_col);
			}
			else if (ELEM(tselem->type, TSE_RNA_PROPERTY, TSE_RNA_ARRAY_ELEM)) {
				UI_GetThemeColorBlend3ubv(TH_BACK, TH_TEXT, 0.75f, text_col);
				text_col[3] = 255;
			}
			else {
				UI_GetThemeColor4ubv(TH_TEXT, text_col);
			}
			text_col[3] *= alpha_fac;

			UI_fontstyle_draw_simple(fstyle, startx + offsx, *starty + 5 * ufac, te->name, text_col);
		}

		offsx += (int)(UI_UNIT_X + UI_fontstyle_string_width(fstyle, te->name));

		/* closed item, we draw the icons, not when it's a scene, or master-server list though */
		if (!TSELEM_OPEN(tselem, soops)) {
			if (te->subtree.first) {
				if (tselem->type == 0 && te->idcode == ID_SCE) {
					/* pass */
				}
				/* this tree element always has same amount of branches, so don't draw */
				else if (tselem->type != TSE_R_LAYER) {
					int tempx = startx + offsx;

					GPU_blend(true);

					/* divider */
					{
						GPUVertFormat *format = immVertexFormat();
						uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
						unsigned char col[4];

						immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
						UI_GetThemeColorShade4ubv(TH_BACK, -40, col);
						col[3] *= alpha_fac;

						immUniformColor4ubv(col);
						immRecti(pos, tempx   - 10.0f * ufac,
						         *starty +  4.0f * ufac,
						         tempx   -  8.0f * ufac,
						         *starty + UI_UNIT_Y - 4.0f * ufac);
						immUnbindProgram();
					}

					MergedIconRow merged = {{0}};
					outliner_draw_iconrow(
					        C, block, fstyle, scene, view_layer, soops, &te->subtree, 0, xmax, &tempx,
					        *starty, alpha_fac, &merged);

					GPU_blend(false);
				}
			}
		}
	}
	/* store coord and continue, we need coordinates for elements outside view too */
	te->xs = startx;
	te->ys = *starty;
	te->xend = startx + offsx;

	if (TSELEM_OPEN(tselem, soops)) {
		*starty -= UI_UNIT_Y;

		for (TreeElement *ten = te->subtree.first; ten; ten = ten->next) {
			/* check if element needs to be drawn grayed out, but also gray out
			 * childs of a grayed out parent (pass on draw_grayed_out to childs) */
			bool draw_childs_grayed_out = draw_grayed_out || (ten->flag & TE_DRAGGING);
			outliner_draw_tree_element(
			        C, block, fstyle, scene, view_layer,
			        ar, soops, ten, draw_childs_grayed_out,
			        startx + UI_UNIT_X, starty, te_edit);
		}
	}
	else {
		for (TreeElement *ten = te->subtree.first; ten; ten = ten->next) {
			outliner_set_coord_tree_element(ten, startx, *starty);
		}

		*starty -= UI_UNIT_Y;
	}
}

static void outliner_draw_hierarchy_lines_recursive(
        unsigned pos, SpaceOops *soops, ListBase *lb, int startx,
        const unsigned char col[4], bool draw_grayed_out,
        int *starty)
{
	TreeElement *te, *te_vertical_line_last = NULL;
	int y1, y2;

	if (BLI_listbase_is_empty(lb)) {
		return;
	}

	const unsigned char grayed_alpha = col[3] / 2;

	/* For vertical lines between objects. */
	y1 = y2 = *starty;
	for (te = lb->first; te; te = te->next) {
		bool draw_childs_grayed_out = draw_grayed_out || (te->flag & TE_DRAGGING);
		TreeStoreElem *tselem = TREESTORE(te);

		if (draw_childs_grayed_out) {
			immUniformColor3ubvAlpha(col, grayed_alpha);
		}
		else {
			immUniformColor4ubv(col);
		}

		/* Horizontal Line? */
		if (tselem->type == 0 && (te->idcode == ID_OB || te->idcode == ID_SCE)) {
			immRecti(pos, startx, *starty, startx + UI_UNIT_X, *starty - 1);

			/* Vertical Line? */
			if (te->idcode == ID_OB) {
				te_vertical_line_last = te;
				y2 = *starty;
			}
		}

		*starty -= UI_UNIT_Y;

		if (TSELEM_OPEN(tselem, soops))
			outliner_draw_hierarchy_lines_recursive(
			        pos, soops, &te->subtree, startx + UI_UNIT_X,
			        col, draw_childs_grayed_out, starty);
	}

	if (draw_grayed_out) {
		immUniformColor3ubvAlpha(col, grayed_alpha);
	}
	else {
		immUniformColor4ubv(col);
	}

	/* Vertical line. */
	te = te_vertical_line_last;
	if ((te != NULL) && (te->parent || lb->first != lb->last)) {
		immRecti(pos, startx, y1 + UI_UNIT_Y, startx + 1, y2);
	}
}

static void outliner_draw_hierarchy_lines(SpaceOops *soops, ListBase *lb, int startx, int *starty)
{
	GPUVertFormat *format = immVertexFormat();
	uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
	unsigned char col[4];

	immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
	UI_GetThemeColorBlend3ubv(TH_BACK, TH_TEXT, 0.4f, col);
	col[3] = 255;

	GPU_blend(true);
	outliner_draw_hierarchy_lines_recursive(pos, soops, lb, startx, col, false, starty);
	GPU_blend(false);

	immUnbindProgram();
}

static void outliner_draw_struct_marks(ARegion *ar, SpaceOops *soops, ListBase *lb, int *starty)
{
	for (TreeElement *te = lb->first; te; te = te->next) {
		TreeStoreElem *tselem = TREESTORE(te);

		/* selection status */
		if (TSELEM_OPEN(tselem, soops)) {
			if (tselem->type == TSE_RNA_STRUCT) {
				GPUVertFormat *format = immVertexFormat();
				uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
				immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
				immThemeColorShadeAlpha(TH_BACK, -15, -200);
				immRecti(pos, 0, *starty + 1, (int)ar->v2d.cur.xmax, *starty + UI_UNIT_Y - 1);
				immUnbindProgram();
			}
		}

		*starty -= UI_UNIT_Y;
		if (TSELEM_OPEN(tselem, soops)) {
			outliner_draw_struct_marks(ar, soops, &te->subtree, starty);
			if (tselem->type == TSE_RNA_STRUCT) {
				GPUVertFormat *format = immVertexFormat();
				uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
				immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
				immThemeColorShadeAlpha(TH_BACK, -15, -200);

				immBegin(GPU_PRIM_LINES, 2);
				immVertex2f(pos, 0, (float)*starty + UI_UNIT_Y);
				immVertex2f(pos, ar->v2d.cur.xmax, (float)*starty + UI_UNIT_Y);
				immEnd();

				immUnbindProgram();
			}
		}
	}
}

static void outliner_draw_highlights_recursive(
        unsigned pos, const ARegion *ar, const SpaceOops *soops, const ListBase *lb,
        const float col_selection[4], const float col_highlight[4], const float col_searchmatch[4],
        int start_x, int *io_start_y)
{
	const bool is_searching = (
	        SEARCHING_OUTLINER(soops) ||
	        (soops->outlinevis == SO_DATA_API &&
	         soops->search_string[0] != 0));

	for (TreeElement *te = lb->first; te; te = te->next) {
		const TreeStoreElem *tselem = TREESTORE(te);
		const int start_y = *io_start_y;

		/* selection status */
		if (tselem->flag & TSE_SELECTED) {
			immUniformColor4fv(col_selection);
			immRecti(pos, 0, start_y + 1, (int)ar->v2d.cur.xmax, start_y + UI_UNIT_Y - 1);
		}

		/* highlights */
		if (tselem->flag & (TSE_DRAG_ANY | TSE_HIGHLIGHTED | TSE_SEARCHMATCH)) {
			const int end_x = (int)ar->v2d.cur.xmax;

			if (tselem->flag & TSE_DRAG_ANY) {
				/* drag and drop highlight */
				float col[4];
				UI_GetThemeColorShade4fv(TH_BACK, -40, col);

				if (tselem->flag & TSE_DRAG_BEFORE) {
					immUniformColor4fv(col);
					immRecti(pos, start_x, start_y + UI_UNIT_Y - 1, end_x, start_y + UI_UNIT_Y + 1);
				}
				else if (tselem->flag & TSE_DRAG_AFTER) {
					immUniformColor4fv(col);
					immRecti(pos, start_x, start_y - 1, end_x, start_y + 1);
				}
				else {
					immUniformColor3fvAlpha(col, col[3] * 0.5f);
					immRecti(pos, start_x, start_y + 1, end_x, start_y + UI_UNIT_Y - 1);
				}
			}
			else {
				if (is_searching && (tselem->flag & TSE_SEARCHMATCH)) {
					/* search match highlights
					 *   we don't expand items when searching in the datablocks but we
					 *   still want to highlight any filter matches. */
					immUniformColor4fv(col_searchmatch);
					immRecti(pos, start_x, start_y + 1, end_x, start_y + UI_UNIT_Y - 1);
				}
				else if (tselem->flag & TSE_HIGHLIGHTED) {
					/* mouse hover highlight */
					immUniformColor4fv(col_highlight);
					immRecti(pos, 0, start_y + 1, end_x, start_y + UI_UNIT_Y - 1);
				}
			}
		}

		*io_start_y -= UI_UNIT_Y;
		if (TSELEM_OPEN(tselem, soops)) {
			outliner_draw_highlights_recursive(
			        pos, ar, soops, &te->subtree, col_selection, col_highlight, col_searchmatch,
			        start_x + UI_UNIT_X, io_start_y);
		}
	}
}

static void outliner_draw_highlights(ARegion *ar, SpaceOops *soops, int startx, int *starty)
{
	const float col_highlight[4] = {1.0f, 1.0f, 1.0f, 0.13f};
	float col_selection[4], col_searchmatch[4];

	UI_GetThemeColor3fv(TH_SELECT_HIGHLIGHT, col_selection);
	col_selection[3] = 1.0f; /* no alpha */
	UI_GetThemeColor4fv(TH_MATCH, col_searchmatch);
	col_searchmatch[3] = 0.5f;

	GPU_blend(true);
	GPUVertFormat *format = immVertexFormat();
	uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
	immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
	outliner_draw_highlights_recursive(
	        pos, ar, soops, &soops->tree, col_selection, col_highlight, col_searchmatch,
	        startx, starty);
	immUnbindProgram();
	GPU_blend(false);
}

static void outliner_draw_tree(
        bContext *C, uiBlock *block, Scene *scene, ViewLayer *view_layer,
        ARegion *ar, SpaceOops *soops, const bool has_restrict_icons,
        TreeElement **te_edit)
{
	const uiFontStyle *fstyle = UI_FSTYLE_WIDGET;
	int starty, startx;

	GPU_blend_set_func_separate(GPU_SRC_ALPHA, GPU_ONE_MINUS_SRC_ALPHA, GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA); // only once

	if (soops->outlinevis == SO_DATA_API) {
		/* struct marks */
		starty = (int)ar->v2d.tot.ymax - UI_UNIT_Y - OL_Y_OFFSET;
		outliner_draw_struct_marks(ar, soops, &soops->tree, &starty);
	}

	/* draw highlights before hierarchy */
	starty = (int)ar->v2d.tot.ymax - UI_UNIT_Y - OL_Y_OFFSET;
	startx = 0;
	outliner_draw_highlights(ar, soops, startx, &starty);

	/* set scissor so tree elements or lines can't overlap restriction icons */
	float scissor[4] = {0};
	if (has_restrict_icons) {
		int mask_x = BLI_rcti_size_x(&ar->v2d.mask) - (int)OL_TOGW + 1;
		CLAMP_MIN(mask_x, 0);

		GPU_scissor_get_f(scissor);
		GPU_scissor(0, 0, mask_x, ar->winy);
	}

	// gray hierarchy lines

	starty = (int)ar->v2d.tot.ymax - UI_UNIT_Y / 2 - OL_Y_OFFSET;
	startx = UI_UNIT_X / 2 - 1.0f;
	outliner_draw_hierarchy_lines(soops, &soops->tree, startx, &starty);

	// items themselves
	starty = (int)ar->v2d.tot.ymax - UI_UNIT_Y - OL_Y_OFFSET;
	startx = 0;
	for (TreeElement *te = soops->tree.first; te; te = te->next) {
		outliner_draw_tree_element(
		        C, block, fstyle, scene, view_layer,
		        ar, soops, te, (te->flag & TE_DRAGGING) != 0,
		        startx, &starty, te_edit);
	}

	if (has_restrict_icons) {
		/* reset scissor */
		GPU_scissor(UNPACK4(scissor));
	}
}


static void outliner_back(ARegion *ar)
{
	int ystart;

	ystart = (int)ar->v2d.tot.ymax;
	ystart = UI_UNIT_Y * (ystart / (UI_UNIT_Y)) - OL_Y_OFFSET;

	GPUVertFormat *format = immVertexFormat();
	uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);

	immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
	immUniformThemeColorShade(TH_BACK, 6);

	const float x1 = 0.0f, x2 = ar->v2d.cur.xmax;
	float y1 = ystart, y2;
	int tot = (int)floor(ystart - ar->v2d.cur.ymin + 2 * UI_UNIT_Y) / (2 * UI_UNIT_Y);

	if (tot > 0) {
		immBegin(GPU_PRIM_TRIS, 6 * tot);
		while (tot--) {
			y1 -= 2 * UI_UNIT_Y;
			y2 = y1 + UI_UNIT_Y;
			immVertex2f(pos, x1, y1);
			immVertex2f(pos, x2, y1);
			immVertex2f(pos, x2, y2);

			immVertex2f(pos, x1, y1);
			immVertex2f(pos, x2, y2);
			immVertex2f(pos, x1, y2);
		}
		immEnd();
	}
	immUnbindProgram();
}

static void outliner_draw_restrictcols(ARegion *ar)
{
	GPU_line_width(1.0f);

	uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_I32, 2, GPU_FETCH_INT_TO_FLOAT);
	immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);
	immUniformThemeColorShadeAlpha(TH_BACK, -15, -200);
	immBegin(GPU_PRIM_LINES, 8);

	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_HIDEX), (int)ar->v2d.cur.ymax);
	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_HIDEX), (int)ar->v2d.cur.ymin);

	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), (int)ar->v2d.cur.ymax);
	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_VIEWX), (int)ar->v2d.cur.ymin);

	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), (int)ar->v2d.cur.ymax);
	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_SELECTX), (int)ar->v2d.cur.ymin);

	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), (int)ar->v2d.cur.ymax);
	immVertex2i(pos, (int)(ar->v2d.cur.xmax - OL_TOG_RESTRICT_RENDERX), (int)ar->v2d.cur.ymin);

	immEnd();
	immUnbindProgram();
}

/* ****************************************************** */
/* Main Entrypoint - Draw contents of Outliner editor */

void draw_outliner(const bContext *C)
{
	Main *mainvar = CTX_data_main(C);
	Scene *scene = CTX_data_scene(C);
	ViewLayer *view_layer = CTX_data_view_layer(C);
	ARegion *ar = CTX_wm_region(C);
	View2D *v2d = &ar->v2d;
	SpaceOops *soops = CTX_wm_space_outliner(C);
	uiBlock *block;
	int sizey = 0, sizex = 0, sizex_rna = 0;
	TreeElement *te_edit = NULL;
	bool has_restrict_icons;

	outliner_build_tree(mainvar, scene, view_layer, soops, ar); // always

	/* get extents of data */
	outliner_height(soops, &soops->tree, &sizey);

	if (soops->outlinevis == SO_DATA_API) {
		/* RNA has two columns:
		 *  - column 1 is (max_width + OL_RNA_COL_SPACEX) or
		 *				 (OL_RNA_COL_X), whichever is wider...
		 *	- column 2 is fixed at OL_RNA_COL_SIZEX
		 *
		 *  (*) XXX max width for now is a fixed factor of (UI_UNIT_X * (max_indention + 100))
		 */

		/* get actual width of column 1 */
		outliner_rna_width(soops, &soops->tree, &sizex_rna, 0);
		sizex_rna = max_ii(OL_RNA_COLX, sizex_rna + OL_RNA_COL_SPACEX);

		/* get width of data (for setting 'tot' rect, this is column 1 + column 2 + a bit extra) */
		sizex = sizex_rna + OL_RNA_COL_SIZEX + 50;
		has_restrict_icons = false;
	}
	else {
		/* width must take into account restriction columns (if visible) so that entries will still be visible */
		//outliner_width(soops, &soops->tree, &sizex);
		// XXX should use outliner_width instead when te->xend will be set correctly...
		outliner_rna_width(soops, &soops->tree, &sizex, 0);

		/* constant offset for restriction columns */
		// XXX this isn't that great yet...
		if ((soops->flag & SO_HIDE_RESTRICTCOLS) == 0) {
			sizex += OL_TOGW * 3;
		}

		has_restrict_icons = !(soops->flag & SO_HIDE_RESTRICTCOLS);
	}

	/* adds vertical offset */
	sizey += OL_Y_OFFSET;

	/* update size of tot-rect (extents of data/viewable area) */
	UI_view2d_totRect_set(v2d, sizex, sizey);

	/* force display to pixel coords */
	v2d->flag |= (V2D_PIXELOFS_X | V2D_PIXELOFS_Y);
	/* set matrix for 2d-view controls */
	UI_view2d_view_ortho(v2d);

	/* draw outliner stuff (background, hierarchy lines and names) */
	outliner_back(ar);
	block = UI_block_begin(C, ar, __func__, UI_EMBOSS);
	outliner_draw_tree(
	        (bContext *)C, block, scene, view_layer,
	        ar, soops, has_restrict_icons, &te_edit);

	/* Default to no emboss for outliner UI. */
	UI_block_emboss_set(block, UI_EMBOSS_NONE);

	if (soops->outlinevis == SO_DATA_API) {
		/* draw rna buttons */
		outliner_draw_rnacols(ar, sizex_rna);

		UI_block_emboss_set(block, UI_EMBOSS);
		outliner_draw_rnabuts(block, ar, soops, sizex_rna, &soops->tree);
		UI_block_emboss_set(block, UI_EMBOSS_NONE);
	}
	else if ((soops->outlinevis == SO_ID_ORPHANS) && has_restrict_icons) {
		/* draw user toggle columns */
		outliner_draw_restrictcols(ar);
		outliner_draw_userbuts(block, ar, soops, &soops->tree);
	}
	else if (has_restrict_icons) {
		/* draw restriction columns */
		outliner_draw_restrictcols(ar);

		outliner_draw_restrictbuts(block, scene, view_layer, ar, soops, &soops->tree);
	}

	UI_block_emboss_set(block, UI_EMBOSS);

	/* draw edit buttons if nessecery */
	if (te_edit) {
		outliner_buttons(C, block, ar, te_edit);
	}

	UI_block_end(C, block);
	UI_block_draw(C, block);
}
