/**
 *	
 * $Id$ 
 *
 * ***** BEGIN GPL/BL DUAL 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. The Blender
 * Foundation also sells licenses for use in proprietary software under
 * the Blender License.  See http://www.blender.org/BL/ for information
 * about this.
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL/BL DUAL LICENSE BLOCK *****
 */
#ifndef BKE_MODIFIER_H
#define BKE_MODIFIER_H

struct DerivedMesh;
struct ModifierData;
struct DagForest;
struct DagNode;
struct Object;

typedef enum {
		/* Should not be used, only for None modifier type */
	eModifierTypeType_None,

		/* Modifier only does deformation, implies that modifier
		 * type should have a valid deformVerts function. OnlyDeform
		 * style modifiers implicitly accept either mesh or CV
		 * input but should still declare flags appropriately.
		 */
	eModifierTypeType_OnlyDeform,

	eModifierTypeType_Constructive,
	eModifierTypeType_Nonconstructive,
} ModifierTypeType;

typedef enum {
	eModifierTypeFlag_AcceptsMesh = (1<<0),
	eModifierTypeFlag_AcceptsCVs = (1<<1),
	eModifierTypeFlag_SupportsMapping = (1<<2),
	eModifierTypeFlag_SupportsEditmode = (1<<3),
} ModifierTypeFlag;

typedef struct ModifierTypeInfo {
		/* The user visible name for this modifier */
	char name[32];

		/* The DNA struct name for the modifier data type, used to
		 * write the DNA data out.
		 */
	char structName[32];

		/* The size of the modifier data type, used by allocation. */
	int structSize;

	ModifierTypeType type;
	ModifierTypeFlag flags;

		/* Initialize new instance data for this modifier type, this function
		 * should set modifier variables to their default values.
		 * 
		 * This function is optional.
		 */
	void (*initData)(struct ModifierData *md);

		/* Free internal modifier data variables, this function should
		 * not free the _md_ variable itself.
		 *
		 * This function is optional.
		 */
	void (*freeData)(struct ModifierData *md);

		/* Return a boolean value indicating if this modifier is able to be calculated
		 * based on the modifier data. This is *not* regarding the md->flag, that is
		 * tested by the system, this is just if the data validates (for example, a
		 * lattice will return false if the lattice object is not defined).
		 *
		 * This function is optional (assumes never disabled if not present).
		 */
	int (*isDisabled)(struct ModifierData *md);

		/* Add the appropriate relations to the DEP graph depending on the modifier
		 * data. 
		 *
		 * This function is optional.
		 */
	void (*updateDepgraph)(struct ModifierData *md, struct DagForest *forest, struct Object *ob, struct DagNode *obNode);

		/* Should return true if the modifier needs to be recalculated on time changes.
		 *
		 * This function is optional (assumes false if not present).
		 */
	int (*dependsOnTime)(struct ModifierData *md);

		/* Only for deform types, should apply the deformation
		 * to the given vertex array. If the deformer requires information from
		 * the object it can obtain it from the _derivedData_ argument if non-NULL,
		 * and otherwise the _ob_ argument.
		 */
	void (*deformVerts)(struct ModifierData *md, struct Object *ob, void *derivedData, float (*vertexCos)[3], int numVerts);

		/* Like deformVerts but called during editmode (for supporting modifiers) */
	void (*deformVertsEM)(struct ModifierData *md, struct Object *ob, void *editData, void *derivedData, float (*vertexCos)[3], int numVerts);

		/* For non-deform types: apply the modifier and return a new derived
		 * data object (type is dependent on object type). If the _derivedData_
		 * argument is non-NULL then the modifier should read the object data 
		 * from the derived object instead of the actual object data. 
		 *
		 * If the _vertexCos_ argument is non-NULL then the modifier should read 
		 * the vertex coordinates from that (even if _derivedData_ is non-NULL).
		 * The length of the _vertexCos_ array is either the number of verts in
		 * the derived object (if non-NULL) or otherwise the number of verts in
		 * the original object.
		 *
		 * The _useRenderParams_ indicates if the modifier is being applied in
		 * the service of the renderer which may alter quality settings.
		 *
		 * The _isFinalCalc_ parameter indicates if the modifier is being calculated
		 * for a final result or for something temporary (like orcos). This is a hack
		 * at the moment, it is meant so subsurf can know if it is safe to reuse its
		 * internal cache.
		 *
		 * The modifier is expected to release (or reuse) the _derivedData_ argument
		 * if non-NULL. The modifier *MAY NOT* share the _vertexCos_ argument.
		 */
	void *(*applyModifier)(struct ModifierData *md, struct Object *ob, void *derivedData, float (*vertexCos)[3], int useRenderParams, int isFinalCalc);

		/* Like applyModifier but called during editmode (for supporting modifiers).
		 * 
		 * The derived object that is returned must support the operations that are expected
		 * from editmode objects. The same qualifications regarding _derivedData_ and _vertexCos_
		 * apply as for applyModifier.
		 */
	void *(*applyModifierEM)(struct ModifierData *md, struct Object *ob, void *editData, void *derivedData, float (*vertexCos)[3]);
} ModifierTypeInfo;

ModifierTypeInfo *modifierType_get_info(ModifierType type);

	/* Modifier utility calls, do call through type pointer and return
	 * default values if pointer is optional.
	 */
struct ModifierData*	modifier_new			(int type);
void					modifier_free			(struct ModifierData *md);

int						modifier_dependsOnTime	(struct ModifierData *md);

#endif