/*
 * 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 bke
 */

#ifndef __CCGSUBSURF_INLINE_H__
#define __CCGSUBSURF_INLINE_H__

BLI_INLINE int ccg_gridsize(int level)
{
	BLI_assert(level > 0);
	BLI_assert(level <= CCGSUBSURF_LEVEL_MAX + 1);
	return (1 << (level - 1)) + 1;
}

BLI_INLINE int ccg_edgesize(int level)
{
	BLI_assert(level > 0);
	BLI_assert(level <= CCGSUBSURF_LEVEL_MAX + 1);
	return 1 + (1 << level);
}

BLI_INLINE int ccg_spacing(int high_level, int low_level)
{
	BLI_assert(high_level > 0 && low_level > 0);
	BLI_assert(high_level >= low_level);
	BLI_assert((high_level - low_level) <= CCGSUBSURF_LEVEL_MAX);
	return 1 << (high_level - low_level);
}

BLI_INLINE int ccg_edgebase(int level)
{
	BLI_assert(level > 0);
	BLI_assert(level <= CCGSUBSURF_LEVEL_MAX + 1);
	return level + (1 << level) - 1;
}

/* **** */

BLI_INLINE byte *VERT_getLevelData(CCGVert *v)
{
    return (byte *)(&(v)[1]);
}

BLI_INLINE byte *EDGE_getLevelData(CCGEdge *e)
{
    return (byte *)(&(e)[1]);
}

BLI_INLINE CCGVert **FACE_getVerts(CCGFace *f)
{
    return (CCGVert **)(&f[1]);
}

BLI_INLINE CCGEdge **FACE_getEdges(CCGFace *f)
{
    return (CCGEdge **)(&(FACE_getVerts(f)[f->numVerts]));
}

BLI_INLINE byte *FACE_getCenterData(CCGFace *f)
{
    return (byte *)(&(FACE_getEdges(f)[(f)->numVerts]));
}

/* **** */

BLI_INLINE void *ccg_vert_getCo(CCGVert *v, int lvl, int dataSize)
{
	return &VERT_getLevelData(v)[lvl * dataSize];
}

BLI_INLINE float *ccg_vert_getNo(CCGVert *v,
                                 int lvl,
                                 int dataSize,
                                 int normalDataOffset)
{
    return (float *) &VERT_getLevelData(v)[lvl * dataSize + normalDataOffset];
}

BLI_INLINE void *ccg_edge_getCo(CCGEdge *e, int lvl, int x, int dataSize)
{
	int levelBase = ccg_edgebase(lvl);
	return &EDGE_getLevelData(e)[dataSize * (levelBase + x)];
}

BLI_INLINE float *ccg_edge_getNo(CCGEdge *e,
                                 int lvl,
                                 int x,
                                 int dataSize,
                                 int normalDataOffset)
{
	int levelBase = ccg_edgebase(lvl);
	return (float *) &EDGE_getLevelData(e)[dataSize * (levelBase + x) + normalDataOffset];
}

BLI_INLINE void *ccg_face_getIECo(CCGFace *f, int lvl, int S, int x, int levels, int dataSize)
{
	int maxGridSize = ccg_gridsize(levels);
	int spacing = ccg_spacing(levels, lvl);
	byte *gridBase = FACE_getCenterData(f) + dataSize * (1 + S * (maxGridSize + maxGridSize * maxGridSize));
	return &gridBase[dataSize * x * spacing];
}

BLI_INLINE void *ccg_face_getIENo(CCGFace *f, int lvl, int S, int x, int levels, int dataSize, int normalDataOffset)
{
	int maxGridSize = ccg_gridsize(levels);
	int spacing = ccg_spacing(levels, lvl);
	byte *gridBase = FACE_getCenterData(f) + dataSize * (1 + S * (maxGridSize + maxGridSize * maxGridSize));
	return &gridBase[dataSize * x * spacing + normalDataOffset];
}

BLI_INLINE void *ccg_face_getIFCo(CCGFace *f, int lvl, int S, int x, int y, int levels, int dataSize)
{
	int maxGridSize = ccg_gridsize(levels);
	int spacing = ccg_spacing(levels, lvl);
	byte *gridBase = FACE_getCenterData(f) + dataSize * (1 + S * (maxGridSize + maxGridSize * maxGridSize));
	return &gridBase[dataSize * (maxGridSize + (y * maxGridSize + x) * spacing)];
}

BLI_INLINE float *ccg_face_getIFNo(CCGFace *f, int lvl, int S, int x, int y, int levels, int dataSize, int normalDataOffset)
{
	int maxGridSize = ccg_gridsize(levels);
	int spacing = ccg_spacing(levels, lvl);
	byte *gridBase = FACE_getCenterData(f) + dataSize * (1 + S * (maxGridSize + maxGridSize * maxGridSize));
	return (float *) &gridBase[dataSize * (maxGridSize + (y * maxGridSize + x) * spacing) + normalDataOffset];
}


BLI_INLINE int ccg_face_getVertIndex(CCGFace *f, CCGVert *v)
{
	int i;
	for (i = 0; i < f->numVerts; i++)
		if (FACE_getVerts(f)[i] == v)
			return i;
	return -1;
}

BLI_INLINE int ccg_face_getEdgeIndex(CCGFace *f, CCGEdge *e)
{
	int i;
	for (i = 0; i < f->numVerts; i++)
		if (FACE_getEdges(f)[i] == e)
			return i;
	return -1;
}

BLI_INLINE void *ccg_face_getIFCoEdge(CCGFace *f, CCGEdge *e, int f_ed_idx, int lvl, int eX, int eY, int levels, int dataSize)
{
	int maxGridSize = ccg_gridsize(levels);
	int spacing = ccg_spacing(levels, lvl);
	int x, y, cx, cy;

	BLI_assert(f_ed_idx == ccg_face_getEdgeIndex(f, e));

	eX = eX * spacing;
	eY = eY * spacing;
	if (e->v0 != FACE_getVerts(f)[f_ed_idx]) {
		eX = (maxGridSize * 2 - 1) - 1 - eX;
	}
	y = maxGridSize - 1 - eX;
	x = maxGridSize - 1 - eY;
	if (x < 0) {
		f_ed_idx = (f_ed_idx + f->numVerts - 1) % f->numVerts;
		cx = y;
		cy = -x;
	}
	else if (y < 0) {
		f_ed_idx = (f_ed_idx + 1) % f->numVerts;
		cx = -y;
		cy = x;
	}
	else {
		cx = x;
		cy = y;
	}
	return ccg_face_getIFCo(f, levels, f_ed_idx, cx, cy, levels, dataSize);
}

BLI_INLINE void Normalize(float no[3])
{
	const float length = sqrtf(no[0] * no[0] + no[1] * no[1] + no[2] * no[2]);

	if (length > EPSILON) {
		const float length_inv = 1.0f / length;

		no[0] *= length_inv;
		no[1] *= length_inv;
		no[2] *= length_inv;
	}
	else {
		NormZero(no);
	}
}

/* Data layers mathematics. */

BLI_INLINE int VertDataEqual(const float a[], const float b[], const CCGSubSurf *ss)
{
	int i;
	for (i = 0; i < ss->meshIFC.numLayers; i++) {
		if (a[i] != b[i])
			return 0;
	}
	return 1;
}

BLI_INLINE void VertDataZero(float v[], const CCGSubSurf *ss)
{
	memset(v, 0, sizeof(float) * ss->meshIFC.numLayers);
}

BLI_INLINE void VertDataCopy(float dst[], const float src[], const CCGSubSurf *ss)
{
	int i;
	for (i = 0; i < ss->meshIFC.numLayers; i++)
		dst[i] = src[i];
}

BLI_INLINE void VertDataAdd(float a[], const float b[], const CCGSubSurf *ss)
{
	int i;
	for (i = 0; i < ss->meshIFC.numLayers; i++)
		a[i] += b[i];
}

BLI_INLINE void VertDataSub(float a[], const float b[], const CCGSubSurf *ss)
{
	int i;
	for (i = 0; i < ss->meshIFC.numLayers; i++)
		a[i] -= b[i];
}

BLI_INLINE void VertDataMulN(float v[], float f, const CCGSubSurf *ss)
{
	int i;
	for (i = 0; i < ss->meshIFC.numLayers; i++)
		v[i] *= f;
}

BLI_INLINE void VertDataAvg4(float v[],
                             const float a[], const float b[],
                             const float c[], const float d[],
                             const CCGSubSurf *ss)
{
	int i;
	for (i = 0; i < ss->meshIFC.numLayers; i++)
		v[i] = (a[i] + b[i] + c[i] + d[i]) * 0.25f;
}

#endif  /* __CCGSUBSURF_INLINE_H__ */