blender-archive/source/blender/editors/metaball/editmball_undo.c

/*
 * 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.
 */

/** \file
 * \ingroup edmeta
 */

#include <math.h>
#include <string.h>

#include "MEM_guardedalloc.h"

#include "CLG_log.h"

#include "BLI_utildefines.h"
#include "BLI_listbase.h"
#include "BLI_array_utils.h"

#include "DNA_defs.h"
#include "DNA_meta_types.h"
#include "DNA_object_types.h"

#include "BKE_context.h"
#include "BKE_layer.h"
#include "BKE_undo_system.h"

#include "DEG_depsgraph.h"

#include "ED_object.h"
#include "ED_mball.h"
#include "ED_undo.h"
#include "ED_util.h"

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

/** We only need this locally. */
static CLG_LogRef LOG = {"ed.undo.mball"};

/* -------------------------------------------------------------------- */
/** \name Undo Conversion
 * \{ */

typedef struct UndoMBall {
	ListBase editelems;
	int lastelem_index;
	size_t undo_size;
} UndoMBall;

/* free all MetaElems from ListBase */
static void freeMetaElemlist(ListBase *lb)
{
	MetaElem *ml;

	if (lb == NULL) {
		return;
	}

	while ((ml = BLI_pophead(lb))) {
		MEM_freeN(ml);
	}
}

static void undomball_to_editmball(UndoMBall *umb, MetaBall *mb)
{
	freeMetaElemlist(mb->editelems);
	mb->lastelem = NULL;

	/* copy 'undo' MetaElems to 'edit' MetaElems */
	int index = 0;
	for (MetaElem *ml_undo = umb->editelems.first; ml_undo; ml_undo = ml_undo->next, index += 1) {
		MetaElem *ml_edit = MEM_dupallocN(ml_undo);
		BLI_addtail(mb->editelems, ml_edit);
		if (index == umb->lastelem_index) {
			mb->lastelem = ml_edit;
		}
	}
}

static void *editmball_from_undomball(UndoMBall *umb, MetaBall *mb)
{
	BLI_assert(BLI_array_is_zeroed(umb, 1));

	/* allocate memory for undo ListBase */
	umb->lastelem_index = -1;

	/* copy contents of current ListBase to the undo ListBase */
	int index = 0;
	for (MetaElem *ml_edit = mb->editelems->first; ml_edit; ml_edit = ml_edit->next, index += 1) {
		MetaElem *ml_undo = MEM_dupallocN(ml_edit);
		BLI_addtail(&umb->editelems, ml_undo);
		if (ml_edit == mb->lastelem) {
			umb->lastelem_index = index;
		}
		umb->undo_size += sizeof(MetaElem);
	}

	return umb;
}

/* free undo ListBase of MetaElems */
static void undomball_free_data(UndoMBall *umb)
{
	freeMetaElemlist(&umb->editelems);
}

static Object *editmball_object_from_context(bContext *C)
{
	Object *obedit = CTX_data_edit_object(C);
	if (obedit && obedit->type == OB_MBALL) {
		MetaBall *mb = obedit->data;
		if (mb->editelems != NULL) {
			return obedit;
		}
	}
	return NULL;
}

/** \} */

/* -------------------------------------------------------------------- */
/** \name Implements ED Undo System
 *
 * \note This is similar for all edit-mode types.
 * \{ */

typedef struct MBallUndoStep_Elem {
	UndoRefID_Object obedit_ref;
	UndoMBall data;
} MBallUndoStep_Elem;

typedef struct MBallUndoStep {
	UndoStep step;
	MBallUndoStep_Elem *elems;
	uint                elems_len;
} MBallUndoStep;

static bool mball_undosys_poll(bContext *C)
{
	return editmball_object_from_context(C) != NULL;
}

static bool mball_undosys_step_encode(struct bContext *C, struct Main *UNUSED(bmain), UndoStep *us_p)
{
	MBallUndoStep *us = (MBallUndoStep *)us_p;

	/* Important not to use the 3D view when getting objects because all objects
	 * outside of this list will be moved out of edit-mode when reading back undo steps. */
	ViewLayer *view_layer = CTX_data_view_layer(C);
	uint objects_len = 0;
	Object **objects = BKE_view_layer_array_from_objects_in_edit_mode_unique_data(view_layer, NULL, &objects_len);

	us->elems = MEM_callocN(sizeof(*us->elems) * objects_len, __func__);
	us->elems_len = objects_len;

	for (uint i = 0; i < objects_len; i++) {
		Object *ob = objects[i];
		MBallUndoStep_Elem *elem = &us->elems[i];

		elem->obedit_ref.ptr = ob;
		MetaBall *mb = ob->data;
		editmball_from_undomball(&elem->data, mb);
		us->step.data_size += elem->data.undo_size;
	}
	MEM_freeN(objects);
	return true;
}

static void mball_undosys_step_decode(struct bContext *C, struct Main *UNUSED(bmain), UndoStep *us_p, int UNUSED(dir))
{
	MBallUndoStep *us = (MBallUndoStep *)us_p;

	/* Load all our objects  into edit-mode, clear everything else. */
	ED_undo_object_editmode_restore_helper(C, &us->elems[0].obedit_ref.ptr, us->elems_len, sizeof(*us->elems));

	BLI_assert(mball_undosys_poll(C));

	for (uint i = 0; i < us->elems_len; i++) {
		MBallUndoStep_Elem *elem = &us->elems[i];
		Object *obedit = elem->obedit_ref.ptr;
		MetaBall *mb = obedit->data;
		if (mb->editelems == NULL) {
			/* Should never fail, may not crash but can give odd behavior. */
			CLOG_ERROR(&LOG, "name='%s', failed to enter edit-mode for object '%s', undo state invalid", us_p->name, obedit->id.name);
			continue;
		}
		undomball_to_editmball(&elem->data, mb);
		DEG_id_tag_update(&obedit->id, ID_RECALC_GEOMETRY);
	}

	/* The first element is always active */
	ED_undo_object_set_active_or_warn(CTX_data_view_layer(C), us->elems[0].obedit_ref.ptr, us_p->name, &LOG);

	WM_event_add_notifier(C, NC_GEOM | ND_DATA, NULL);
}

static void mball_undosys_step_free(UndoStep *us_p)
{
	MBallUndoStep *us = (MBallUndoStep *)us_p;

	for (uint i = 0; i < us->elems_len; i++) {
		MBallUndoStep_Elem *elem = &us->elems[i];
		undomball_free_data(&elem->data);
	}
	MEM_freeN(us->elems);
}

static void mball_undosys_foreach_ID_ref(
        UndoStep *us_p, UndoTypeForEachIDRefFn foreach_ID_ref_fn, void *user_data)
{
	MBallUndoStep *us = (MBallUndoStep *)us_p;

	for (uint i = 0; i < us->elems_len; i++) {
		MBallUndoStep_Elem *elem = &us->elems[i];
		foreach_ID_ref_fn(user_data, ((UndoRefID *)&elem->obedit_ref));
	}
}

/* Export for ED_undo_sys. */
void ED_mball_undosys_type(UndoType *ut)
{
	ut->name = "Edit MBall";
	ut->poll = mball_undosys_poll;
	ut->step_encode = mball_undosys_step_encode;
	ut->step_decode = mball_undosys_step_decode;
	ut->step_free = mball_undosys_step_free;

	ut->step_foreach_ID_ref = mball_undosys_foreach_ID_ref;

	ut->use_context = true;

	ut->step_size = sizeof(MBallUndoStep);

}

/** \} */