/*
 * ***** 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) 2011 by Nicholas Bishop.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/modifiers/intern/MOD_remesh.c
 *  \ingroup modifiers
 */

#include "MEM_guardedalloc.h"

#include "BLI_math_base.h"
#include "BLI_math_vector.h"
#include "BLI_utildefines.h"

#include "BKE_cdderivedmesh.h"
#include "BKE_DerivedMesh.h"

#include "DNA_meshdata_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"

#include "MOD_modifiertypes.h"

#include <assert.h>
#include <stdlib.h>
#include <string.h>

#ifdef WITH_MOD_REMESH
#  include "dualcon.h"
#endif

static void initData(ModifierData *md)
{
	RemeshModifierData *rmd = (RemeshModifierData *) md;

	rmd->scale = 0.9;
	rmd->depth = 4;
	rmd->hermite_num = 1;
	rmd->flag = MOD_REMESH_FLOOD_FILL;
	rmd->mode = MOD_REMESH_SHARP_FEATURES;
	rmd->threshold = 1;
}

static void copyData(ModifierData *md, ModifierData *target)
{
#if 0
	RemeshModifierData *rmd = (RemeshModifierData *) md;
	RemeshModifierData *trmd = (RemeshModifierData *) target;
#endif
	modifier_copyData_generic(md, target);
}

#ifdef WITH_MOD_REMESH

static void init_dualcon_mesh(DualConInput *mesh, DerivedMesh *dm)
{
	memset(mesh, 0, sizeof(DualConInput));

	mesh->co = (void *)dm->getVertArray(dm);
	mesh->co_stride = sizeof(MVert);
	mesh->totco = dm->getNumVerts(dm);

	mesh->mloop = (void *)dm->getLoopArray(dm);
	mesh->loop_stride = sizeof(MLoop);
	mesh->looptri = (void *)dm->getLoopTriArray(dm);
	mesh->tri_stride = sizeof(MLoopTri);
	mesh->tottri = dm->getNumLoopTri(dm);

	INIT_MINMAX(mesh->min, mesh->max);
	dm->getMinMax(dm, mesh->min, mesh->max);
}

/* simple structure to hold the output: a CDDM and two counters to
 * keep track of the current elements */
typedef struct {
	DerivedMesh *dm;
	int curvert, curface;
} DualConOutput;

/* allocate and initialize a DualConOutput */
static void *dualcon_alloc_output(int totvert, int totquad)
{
	DualConOutput *output;

	if (!(output = MEM_callocN(sizeof(DualConOutput),
	                           "DualConOutput")))
	{
		return NULL;
	}
	
	output->dm = CDDM_new(totvert, 0, 0, 4 * totquad, totquad);
	return output;
}

static void dualcon_add_vert(void *output_v, const float co[3])
{
	DualConOutput *output = output_v;
	DerivedMesh *dm = output->dm;
	
	assert(output->curvert < dm->getNumVerts(dm));
	
	copy_v3_v3(CDDM_get_verts(dm)[output->curvert].co, co);
	output->curvert++;
}

static void dualcon_add_quad(void *output_v, const int vert_indices[4])
{
	DualConOutput *output = output_v;
	DerivedMesh *dm = output->dm;
	MLoop *mloop;
	MPoly *cur_poly;
	int i;
	
	assert(output->curface < dm->getNumPolys(dm));

	mloop = CDDM_get_loops(dm);
	cur_poly = CDDM_get_poly(dm, output->curface);
	
	cur_poly->loopstart = output->curface * 4;
	cur_poly->totloop = 4;
	for (i = 0; i < 4; i++)
		mloop[output->curface * 4 + i].v = vert_indices[i];
	
	output->curface++;
}

static DerivedMesh *applyModifier(ModifierData *md,
                                  Object *UNUSED(ob),
                                  DerivedMesh *dm,
                                  ModifierApplyFlag UNUSED(flag))
{
	RemeshModifierData *rmd;
	DualConOutput *output;
	DualConInput input;
	DerivedMesh *result;
	DualConFlags flags = 0;
	DualConMode mode = 0;

	rmd = (RemeshModifierData *)md;

	init_dualcon_mesh(&input, dm);

	if (rmd->flag & MOD_REMESH_FLOOD_FILL)
		flags |= DUALCON_FLOOD_FILL;

	switch (rmd->mode) {
		case MOD_REMESH_CENTROID:
			mode = DUALCON_CENTROID;
			break;
		case MOD_REMESH_MASS_POINT:
			mode = DUALCON_MASS_POINT;
			break;
		case MOD_REMESH_SHARP_FEATURES:
			mode = DUALCON_SHARP_FEATURES;
			break;
	}
	
	output = dualcon(&input,
	                 dualcon_alloc_output,
	                 dualcon_add_vert,
	                 dualcon_add_quad,
	                 flags,
	                 mode,
	                 rmd->threshold,
	                 rmd->hermite_num,
	                 rmd->scale,
	                 rmd->depth);
	result = output->dm;
	MEM_freeN(output);

	if (rmd->flag & MOD_REMESH_SMOOTH_SHADING) {
		MPoly *mpoly = CDDM_get_polys(result);
		int i, totpoly = result->getNumPolys(result);
		
		/* Apply smooth shading to output faces */
		for (i = 0; i < totpoly; i++) {
			mpoly[i].flag |= ME_SMOOTH;
		}
	}

	CDDM_calc_edges(result);
	result->dirty |= DM_DIRTY_NORMALS;
	return result;
}

#else /* !WITH_MOD_REMESH */

static DerivedMesh *applyModifier(ModifierData *UNUSED(md), Object *UNUSED(ob),
                                  DerivedMesh *derivedData,
                                  ModifierApplyFlag UNUSED(flag))
{
	return derivedData;
}

#endif /* !WITH_MOD_REMESH */

ModifierTypeInfo modifierType_Remesh = {
	/* name */              "Remesh",
	/* structName */        "RemeshModifierData",
	/* structSize */        sizeof(RemeshModifierData),
	/* type */              eModifierTypeType_Nonconstructive,
	/* flags */             eModifierTypeFlag_AcceptsMesh |
	                        eModifierTypeFlag_AcceptsCVs |
	                        eModifierTypeFlag_SupportsEditmode,
	/* copyData */          copyData,
	/* deformVerts */       NULL,
	/* deformMatrices */    NULL,
	/* deformVertsEM */     NULL,
	/* deformMatricesEM */  NULL,
	/* applyModifier */     applyModifier,
	/* applyModifierEM */   NULL,
	/* initData */          initData,
	/* requiredDataMask */  NULL,
	/* freeData */          NULL,
	/* isDisabled */        NULL,
	/* updateDepsgraph */   NULL,
	/* dependsOnTime */     NULL,
	/* dependsOnNormals */	NULL,
	/* foreachObjectLink */ NULL,
	/* foreachIDLink */     NULL,
};