Beispiel #1
0
void calPowerPara(double * power, fftw_complex * fft, int nPower, double dk, double * kk, double * dir, int * n)
{

  for (int iPower = 0; iPower < nPower; iPower++)
  {
    power[iPower] = 0; 
  }

  double kPara;
  int kBin;
  fftw_complex * p; 
  fftw_complex coefFFT;
  p = fft;
  int i, j, k;
  for (int k2 = 0; k2 < n[2]; k2++) 
  for (int j2 = 0; j2 < n[1]; j2++) 
  for (int i2 = 0; i2 < n[0]; i2++) 
  {
    i = PU(i2, n[0]); 
    j = PU(j2, n[1]); 
    k = PU(k2, n[2]); 
    kPara = fabs(i*kk[0]*dir[0] + j*kk[1]*dir[1] + k*kk[2]*dir[2]); 
    kBin = ceil(kPara/dk - 0.5); 
    if (kBin < 0) kBin = 0;
    if (kBin >= nPower) kBin = nPower;
    coefFFT = *p++; 
    power[kBin] += cabs(coefFFT) * cabs(coefFFT); 
  }
}
Beispiel #2
0
void calPowerPerp(double * power, fftw_complex * fft, int nPower, double dk, double * kk, double * dir, int * n)
{
  fftw_complex * p; 
  fftw_complex coefFFT;
  p = fft;

  for (int iPower = 0; iPower < nPower; iPower++)
  {
    power[iPower] = 0; 
  }

  double kPerp; 
  int kBin;
  double xPara, yPara, zPara;
  double xRemn, yRemn, zRemn;
  int i, j, k;
  for (int k2 = 0; k2 < n[2]; k2++) 
  for (int j2 = 0; j2 < n[1]; j2++) 
  for (int i2 = 0; i2 < n[0]; i2++) 
  {
    i = PU(i2, n[0]); 
    j = PU(j2, n[1]); 
    k = PU(k2, n[2]); 
    xPara = i*kk[0]*dir[0]; 
    yPara = j*kk[1]*dir[1]; 
    zPara = k*kk[2]*dir[2]; 
    xRemn = i*kk[0] - xPara;
    yRemn = j*kk[1] - yPara;
    zRemn = k*kk[2] - zPara;
    kPerp = sqrt(xRemn*xRemn + yRemn*yRemn + zRemn*zRemn); 

    kBin = ceil(kPerp/dk - 0.5); 
    if (kBin >= nPower) kBin = nPower;
    coefFFT = *p++; 
    power[kBin] += cabs(coefFFT) * cabs(coefFFT); 
  }
}
void ParametricSurface<Real>::GetFrame (Real u, Real v,
                                        Vector3<Real>& position, Vector3<Real>& tangent0,
                                        Vector3<Real>& tangent1, Vector3<Real>& normal) const
{
	position = P(u, v);

	tangent0 = PU(u, v);
	tangent1 = PV(u, v);
	tangent0.Normalize();  // T0
	tangent1.Normalize();  // temporary T1 just to compute N
	normal = tangent0.UnitCross(tangent1);  // N

	// The normalized first derivatives are not necessarily orthogonal.
	// Recompute T1 so that {T0,T1,N} is an orthonormal set.
	tangent1 = normal.Cross(tangent0);
}
Beispiel #4
0
static void FUNC(intra_pred)(HEVCContext *s, int x0, int y0, int log2_size, int c_idx)
{
#define PU(x) \
    ((x) >> s->sps->log2_min_pu_size)
#define MVF(x, y) \
    (s->ref->tab_mvf[(x) + (y) * min_pu_width])
#define MVF_PU(x, y) \
    MVF(PU(x0 + ((x) << hshift)), PU(y0 + ((y) << vshift)))
#define IS_INTRA(x, y) \
    (MVF_PU(x, y).pred_flag == PF_INTRA)
#define MIN_TB_ADDR_ZS(x, y) \
    s->pps->min_tb_addr_zs[(y) * s->sps->min_tb_width + (x)]
#define EXTEND_LEFT(ptr, start, length) \
        for (i = (start); i > (start) - (length); i--) \
            ptr[i - 1] = ptr[i]
#define EXTEND_RIGHT(ptr, start, length) \
        for (i = (start); i < (start) + (length); i++) \
            ptr[i] = ptr[i - 1]
#define EXTEND_UP(ptr, start, length)   EXTEND_LEFT(ptr, start, length)
#define EXTEND_DOWN(ptr, start, length) EXTEND_RIGHT(ptr, start, length)
#define EXTEND_LEFT_CIP(ptr, start, length) \
        for (i = (start); i > (start) - (length); i--) \
            if (!IS_INTRA(i - 1, -1)) \
                ptr[i - 1] = ptr[i]
#define EXTEND_RIGHT_CIP(ptr, start, length) \
        for (i = (start); i < (start) + (length); i++) \
            if (!IS_INTRA(i, -1)) \
                ptr[i] = ptr[i - 1]
#define EXTEND_UP_CIP(ptr, start, length) \
        for (i = (start); i > (start) - (length); i--) \
            if (!IS_INTRA(-1, i - 1)) \
                ptr[i - 1] = ptr[i]
#define EXTEND_UP_CIP_0(ptr, start, length) \
        for (i = (start); i > (start) - (length); i--) \
            ptr[i - 1] = ptr[i]
#define EXTEND_DOWN_CIP(ptr, start, length) \
        for (i = (start); i < (start) + (length); i++) \
            if (!IS_INTRA(-1, i)) \
                ptr[i] = ptr[i - 1]
    HEVCLocalContext *lc = s->HEVClc;
    int i;
    int hshift = s->sps->hshift[c_idx];
    int vshift = s->sps->vshift[c_idx];
    int size = (1 << log2_size);
    int size_in_luma = size << hshift;
    int size_in_tbs = size_in_luma >> s->sps->log2_min_tb_size;
    int x = x0 >> hshift;
    int y = y0 >> vshift;
    int x_tb = x0 >> s->sps->log2_min_tb_size;
    int y_tb = y0 >> s->sps->log2_min_tb_size;
    int cur_tb_addr = MIN_TB_ADDR_ZS(x_tb, y_tb);

    ptrdiff_t stride = s->frame->linesize[c_idx] / sizeof(pixel);
    pixel *src = (pixel*)s->frame->data[c_idx] + x + y * stride;

    int min_pu_width = s->sps->min_pu_width;

    enum IntraPredMode mode = c_idx ? lc->pu.intra_pred_mode_c :
                              lc->tu.cur_intra_pred_mode;

    pixel left_array[2 * MAX_TB_SIZE + 1];
    pixel filtered_left_array[2 * MAX_TB_SIZE + 1];
    pixel top_array[2 * MAX_TB_SIZE + 1];
    pixel filtered_top_array[2 * MAX_TB_SIZE + 1];

    pixel *left          = left_array + 1;
    pixel *top           = top_array  + 1;
    pixel *filtered_left = filtered_left_array + 1;
    pixel *filtered_top  = filtered_top_array  + 1;

    int cand_bottom_left = lc->na.cand_bottom_left && cur_tb_addr > MIN_TB_ADDR_ZS(x_tb - 1, y_tb + size_in_tbs);
    int cand_left        = lc->na.cand_left;
    int cand_up_left     = lc->na.cand_up_left;
    int cand_up          = lc->na.cand_up;
    int cand_up_right    = lc->na.cand_up_right && cur_tb_addr > MIN_TB_ADDR_ZS(x_tb + size_in_tbs, y_tb - 1);

    int bottom_left_size = (FFMIN(y0 + 2 * size_in_luma, s->sps->height) -
                            (y0 + size_in_luma)) >> vshift;
    int top_right_size   = (FFMIN(x0 + 2 * size_in_luma, s->sps->width) -
                            (x0 + size_in_luma)) >> hshift;

    if (s->pps->constrained_intra_pred_flag == 1) {
        int size_in_luma_pu = PU(size_in_luma);
        int on_pu_edge_x    = !(x0 & ((1 << s->sps->log2_min_pu_size) - 1));
        int on_pu_edge_y    = !(y0 & ((1 << s->sps->log2_min_pu_size) - 1));
        if (!size_in_luma_pu)
            size_in_luma_pu++;
        if (cand_bottom_left == 1 && on_pu_edge_x) {
            int x_left_pu   = PU(x0 - 1);
            int y_bottom_pu = PU(y0 + size_in_luma);
            int max = FFMIN(size_in_luma_pu, s->sps->min_pu_height - y_bottom_pu);
            cand_bottom_left = 0;
            for (i = 0; i < max; i++)
                cand_bottom_left |= (MVF(x_left_pu, y_bottom_pu + i).pred_flag == PF_INTRA);
        }
        if (cand_left == 1 && on_pu_edge_x) {
            int x_left_pu   = PU(x0 - 1);
            int y_left_pu   = PU(y0);
            int max = FFMIN(size_in_luma_pu, s->sps->min_pu_height - y_left_pu);
            cand_left = 0;
            for (i = 0; i < max; i++)
                cand_left |= (MVF(x_left_pu, y_left_pu + i).pred_flag == PF_INTRA);
        }
        if (cand_up_left == 1) {
            int x_left_pu   = PU(x0 - 1);
            int y_top_pu    = PU(y0 - 1);
            cand_up_left = MVF(x_left_pu, y_top_pu).pred_flag == PF_INTRA;
        }
        if (cand_up == 1 && on_pu_edge_y) {
            int x_top_pu    = PU(x0);
            int y_top_pu    = PU(y0 - 1);
            int max = FFMIN(size_in_luma_pu, s->sps->min_pu_width - x_top_pu);
            cand_up = 0;
            for (i = 0; i < max; i++)
                cand_up |= (MVF(x_top_pu + i, y_top_pu).pred_flag == PF_INTRA);
        }
        if (cand_up_right == 1 && on_pu_edge_y) {
            int y_top_pu    = PU(y0 - 1);
            int x_right_pu  = PU(x0 + size_in_luma);
            int max = FFMIN(size_in_luma_pu, s->sps->min_pu_width - x_right_pu);
            cand_up_right = 0;
            for (i = 0; i < max; i++)
                cand_up_right |= (MVF(x_right_pu + i, y_top_pu).pred_flag == PF_INTRA);
        }
        for (i = 0; i < 2 * MAX_TB_SIZE; i++) {
            left[i] = 128;
            top[i]  = 128;
        }
        top[-1] = 128;
    }
    if (cand_bottom_left) {
        for (i = size + bottom_left_size; i < (size << 1); i++)
            if (IS_INTRA(-1, size + bottom_left_size - 1) ||
                !s->pps->constrained_intra_pred_flag)
                left[i] = POS(-1, size + bottom_left_size - 1);
        for (i = size + bottom_left_size - 1; i >= size; i--)
            if (IS_INTRA(-1, i) || !s->pps->constrained_intra_pred_flag)
                left[i] = POS(-1, i);
    }
    if (cand_left)
        for (i = size - 1; i >= 0; i--)
            if (IS_INTRA(-1, i) || !s->pps->constrained_intra_pred_flag)
                left[i] = POS(-1, i);
    if (cand_up_left)
        if (IS_INTRA(-1, -1) || !s->pps->constrained_intra_pred_flag) {
            left[-1] = POS(-1, -1);
            top[-1]  = left[-1];
        }
    if (cand_up)
        for (i = size - 1; i >= 0; i--)
            if (IS_INTRA(i, -1) || !s->pps->constrained_intra_pred_flag)
                top[i] = POS(i, -1);
    if (cand_up_right) {
        for (i = size + top_right_size; i < (size << 1); i++)
            if (IS_INTRA(size + top_right_size - 1, -1) ||
                !s->pps->constrained_intra_pred_flag)
                top[i] = POS(size + top_right_size - 1, -1);
        for (i = size + top_right_size - 1; i >= size; i--)
            if (IS_INTRA(i, -1) || !s->pps->constrained_intra_pred_flag)
                top[i] = POS(i, -1);
    }

    if (s->pps->constrained_intra_pred_flag == 1) {
        if (cand_bottom_left || cand_left || cand_up_left || cand_up || cand_up_right) {
            int size_max_x = x0 + ((2 * size) << hshift) < s->sps->width ?
                                    2 * size : (s->sps->width - x0) >> hshift;
            int size_max_y = y0 + ((2 * size) << vshift) < s->sps->height ?
                                    2 * size : (s->sps->height - y0) >> vshift;
            int j = size + (cand_bottom_left? bottom_left_size: 0) -1;
            if (!cand_up_right) {
                size_max_x = x0 + ((size) << hshift) < s->sps->width ?
                                                    size : (s->sps->width - x0) >> hshift;
            }
            if (!cand_bottom_left) {
                size_max_y = y0 + (( size) << vshift) < s->sps->height ?
                                                     size : (s->sps->height - y0) >> vshift;
            }
Beispiel #5
0
static av_always_inline void FUNC(intra_pred)(HEVCContext *s, int x0, int y0,
                                              int log2_size, int c_idx)
{
#define PU(x) \
    ((x) >> s->sps->log2_min_pu_size)
#define MVF(x, y) \
    (s->ref->tab_mvf[(x) + (y) * min_pu_width])
#define MVF_PU(x, y) \
    MVF(PU(x0 + ((x) << hshift)), PU(y0 + ((y) << vshift)))
#define IS_INTRA(x, y) \
    (MVF_PU(x, y).pred_flag == PF_INTRA)
#define MIN_TB_ADDR_ZS(x, y) \
    s->pps->min_tb_addr_zs[(y) * s->sps->min_tb_width + (x)]

#define EXTEND(ptr, val, len)         \
do {                                  \
    pixel4 pix = PIXEL_SPLAT_X4(val); \
    for (i = 0; i < (len); i += 4)    \
        AV_WN4P(ptr + i, pix);        \
} while (0)

#define EXTEND_RIGHT_CIP(ptr, start, length)                                   \
        for (i = start; i < (start) + (length); i += 4)                        \
            if (!IS_INTRA(i, -1))                                              \
                AV_WN4P(&ptr[i], a);                                           \
            else                                                               \
                a = PIXEL_SPLAT_X4(ptr[i+3])
#define EXTEND_LEFT_CIP(ptr, start, length) \
        for (i = start; i > (start) - (length); i--) \
            if (!IS_INTRA(i - 1, -1)) \
                ptr[i - 1] = ptr[i]
#define EXTEND_UP_CIP(ptr, start, length)                                      \
        for (i = (start); i > (start) - (length); i -= 4)                      \
            if (!IS_INTRA(-1, i - 3))                                          \
                AV_WN4P(&ptr[i - 3], a);                                       \
            else                                                               \
                a = PIXEL_SPLAT_X4(ptr[i - 3])
#define EXTEND_DOWN_CIP(ptr, start, length)                                    \
        for (i = start; i < (start) + (length); i += 4)                        \
            if (!IS_INTRA(-1, i))                                              \
                AV_WN4P(&ptr[i], a);                                           \
            else                                                               \
                a = PIXEL_SPLAT_X4(ptr[i + 3])

    HEVCLocalContext *lc = s->HEVClc;
    int i;
    int hshift = s->sps->hshift[c_idx];
    int vshift = s->sps->vshift[c_idx];
    int size = (1 << log2_size);
    int size_in_luma_h = size << hshift;
    int size_in_tbs_h  = size_in_luma_h >> s->sps->log2_min_tb_size;
    int size_in_luma_v = size << vshift;
    int size_in_tbs_v  = size_in_luma_v >> s->sps->log2_min_tb_size;
    int x = x0 >> hshift;
    int y = y0 >> vshift;
    int x_tb = x0 >> s->sps->log2_min_tb_size;
    int y_tb = y0 >> s->sps->log2_min_tb_size;
    int cur_tb_addr = MIN_TB_ADDR_ZS(x_tb, y_tb);

    ptrdiff_t stride = s->frame->linesize[c_idx] / sizeof(pixel);
    pixel *src = (pixel*)s->frame->data[c_idx] + x + y * stride;

    int min_pu_width = s->sps->min_pu_width;

    enum IntraPredMode mode = c_idx ? lc->tu.cur_intra_pred_mode_c :
                              lc->tu.cur_intra_pred_mode;
    pixel4 a;
    pixel  left_array[2 * MAX_TB_SIZE + 1];
    pixel  filtered_left_array[2 * MAX_TB_SIZE + 1];
    pixel  top_array[2 * MAX_TB_SIZE + 1];
    pixel  filtered_top_array[2 * MAX_TB_SIZE + 1];

    pixel  *left          = left_array + 1;
    pixel  *top           = top_array  + 1;
    pixel  *filtered_left = filtered_left_array + 1;
    pixel  *filtered_top  = filtered_top_array  + 1;
    int cand_bottom_left = lc->na.cand_bottom_left && cur_tb_addr > MIN_TB_ADDR_ZS(x_tb - 1, y_tb + size_in_tbs_v);
    int cand_left        = lc->na.cand_left;
    int cand_up_left     = lc->na.cand_up_left;
    int cand_up          = lc->na.cand_up;
    int cand_up_right    = lc->na.cand_up_right && cur_tb_addr > MIN_TB_ADDR_ZS(x_tb + size_in_tbs_h, y_tb - 1);

    int bottom_left_size = (FFMIN(y0 + 2 * size_in_luma_v, s->sps->height) -
                           (y0 + size_in_luma_v)) >> vshift;
    int top_right_size   = (FFMIN(x0 + 2 * size_in_luma_h, s->sps->width) -
                           (x0 + size_in_luma_h)) >> hshift;

    if (s->pps->constrained_intra_pred_flag == 1) {
        int size_in_luma_pu_v = PU(size_in_luma_v);
        int size_in_luma_pu_h = PU(size_in_luma_h);
        int on_pu_edge_x    = !(x0 & ((1 << s->sps->log2_min_pu_size) - 1));
        int on_pu_edge_y    = !(y0 & ((1 << s->sps->log2_min_pu_size) - 1));
        if (!size_in_luma_pu_h)
            size_in_luma_pu_h++;
        if (cand_bottom_left == 1 && on_pu_edge_x) {
            int x_left_pu   = PU(x0 - 1);
            int y_bottom_pu = PU(y0 + size_in_luma_v);
            int max = FFMIN(size_in_luma_pu_v, s->sps->min_pu_height - y_bottom_pu);
            cand_bottom_left = 0;
            for (i = 0; i < max; i += 2)
                cand_bottom_left |= (MVF(x_left_pu, y_bottom_pu + i).pred_flag == PF_INTRA);
        }
        if (cand_left == 1 && on_pu_edge_x) {
            int x_left_pu   = PU(x0 - 1);
            int y_left_pu   = PU(y0);
            int max = FFMIN(size_in_luma_pu_v, s->sps->min_pu_height - y_left_pu);
            cand_left = 0;
            for (i = 0; i < max; i += 2)
                cand_left |= (MVF(x_left_pu, y_left_pu + i).pred_flag == PF_INTRA);
        }
        if (cand_up_left == 1) {
            int x_left_pu   = PU(x0 - 1);
            int y_top_pu    = PU(y0 - 1);
            cand_up_left = MVF(x_left_pu, y_top_pu).pred_flag == PF_INTRA;
        }
        if (cand_up == 1 && on_pu_edge_y) {
            int x_top_pu    = PU(x0);
            int y_top_pu    = PU(y0 - 1);
            int max = FFMIN(size_in_luma_pu_h, s->sps->min_pu_width - x_top_pu);
            cand_up = 0;
            for (i = 0; i < max; i += 2)
                cand_up |= (MVF(x_top_pu + i, y_top_pu).pred_flag == PF_INTRA);
        }
        if (cand_up_right == 1 && on_pu_edge_y) {
            int y_top_pu    = PU(y0 - 1);
            int x_right_pu  = PU(x0 + size_in_luma_h);
            int max = FFMIN(size_in_luma_pu_h, s->sps->min_pu_width - x_right_pu);
            cand_up_right = 0;
            for (i = 0; i < max; i += 2)
                cand_up_right |= (MVF(x_right_pu + i, y_top_pu).pred_flag == PF_INTRA);
        }
        memset(left, 128, 2 * MAX_TB_SIZE*sizeof(pixel));
        memset(top , 128, 2 * MAX_TB_SIZE*sizeof(pixel));
        top[-1] = 128;
    }
    if (cand_up_left) {
        left[-1] = POS(-1, -1);
        top[-1]  = left[-1];
    }
    if (cand_up)
        memcpy(top, src - stride, size * sizeof(pixel));
    if (cand_up_right) {
        memcpy(top + size, src - stride + size, size * sizeof(pixel));
        EXTEND(top + size + top_right_size, POS(size + top_right_size - 1, -1),
               size - top_right_size);
    }
    if (cand_left)
        for (i = 0; i < size; i++)
            left[i] = POS(-1, i);
    if (cand_bottom_left) {
        for (i = size; i < size + bottom_left_size; i++)
            left[i] = POS(-1, i);
        EXTEND(left + size + bottom_left_size, POS(-1, size + bottom_left_size - 1),
               size - bottom_left_size);
    }

    if (s->pps->constrained_intra_pred_flag == 1) {
        if (cand_bottom_left || cand_left || cand_up_left || cand_up || cand_up_right) {
            int size_max_x = x0 + ((2 * size) << hshift) < s->sps->width ?
                                    2 * size : (s->sps->width - x0) >> hshift;
            int size_max_y = y0 + ((2 * size) << vshift) < s->sps->height ?
                                    2 * size : (s->sps->height - y0) >> vshift;
            int j = size + (cand_bottom_left? bottom_left_size: 0) -1;
            if (!cand_up_right) {
                size_max_x = x0 + ((size) << hshift) < s->sps->width ?
                                                    size : (s->sps->width - x0) >> hshift;
            }
            if (!cand_bottom_left) {
                size_max_y = y0 + (( size) << vshift) < s->sps->height ?
                                                     size : (s->sps->height - y0) >> vshift;
            }
void ParametricSurface<Real>::ComputePrincipalCurvatureInfo (Real u, Real v,
        Real& curv0, Real& curv1, Vector3<Real>& dir0,
        Vector3<Real>& dir1)
{
	// Tangents:  T0 = (x_u,y_u,z_u), T1 = (x_v,y_v,z_v)
	// Normal:    N = Cross(T0,T1)/Length(Cross(T0,T1))
	// Metric Tensor:    G = +-                      -+
	//                       | Dot(T0,T0)  Dot(T0,T1) |
	//                       | Dot(T1,T0)  Dot(T1,T1) |
	//                       +-                      -+
	//
	// Curvature Tensor:  B = +-                          -+
	//                        | -Dot(N,T0_u)  -Dot(N,T0_v) |
	//                        | -Dot(N,T1_u)  -Dot(N,T1_v) |
	//                        +-                          -+
	//
	// Principal curvatures k are the generalized eigenvalues of
	//
	//     Bw = kGw
	//
	// If k is a curvature and w=(a,b) is the corresponding solution to
	// Bw = kGw, then the principal direction as a 3D vector is d = a*U+b*V.
	//
	// Let k1 and k2 be the principal curvatures.  The mean curvature
	// is (k1+k2)/2 and the Gaussian curvature is k1*k2.

	// Compute derivatives.
	Vector3<Real> derU = PU(u,v);
	Vector3<Real> derV = PV(u,v);
	Vector3<Real> derUU = PUU(u,v);
	Vector3<Real> derUV = PUV(u,v);
	Vector3<Real> derVV = PVV(u,v);

	// Compute the metric tensor.
	Matrix2<Real> metricTensor;
	metricTensor[0][0] = derU.Dot(derU);
	metricTensor[0][1] = derU.Dot(derV);
	metricTensor[1][0] = metricTensor[0][1];
	metricTensor[1][1] = derV.Dot(derV);

	// Compute the curvature tensor.
	Vector3<Real> normal = derU.UnitCross(derV);
	Matrix2<Real> curvatureTensor;
	curvatureTensor[0][0] = -normal.Dot(derUU);
	curvatureTensor[0][1] = -normal.Dot(derUV);
	curvatureTensor[1][0] = curvatureTensor[0][1];
	curvatureTensor[1][1] = -normal.Dot(derVV);

	// Characteristic polynomial is 0 = det(B-kG) = c2*k^2+c1*k+c0.
	Real c0 = curvatureTensor.Determinant();
	Real c1 = ((Real)2)*curvatureTensor[0][1]* metricTensor[0][1] -
	          curvatureTensor[0][0]*metricTensor[1][1] -
	          curvatureTensor[1][1]*metricTensor[0][0];
	Real c2 = metricTensor.Determinant();

	// Principal curvatures are roots of characteristic polynomial.
	Real temp = Math<Real>::Sqrt(Math<Real>::FAbs(c1*c1 - ((Real)4)*c0*c2));
	Real mult = ((Real)0.5)/c2;
	curv0 = -mult*(c1+temp);
	curv1 = mult*(-c1+temp);

	// Principal directions are solutions to (B-kG)w = 0,
	// w1 = (b12-k1*g12,-(b11-k1*g11)) OR (b22-k1*g22,-(b12-k1*g12)).
	Real a0 = curvatureTensor[0][1] - curv0*metricTensor[0][1];
	Real a1 = curv0*metricTensor[0][0] - curvatureTensor[0][0];
	Real length = Math<Real>::Sqrt(a0*a0 + a1*a1);
	if (length >= Math<Real>::ZERO_TOLERANCE)
	{
		dir0 = a0*derU + a1*derV;
	}
	else
	{
		a0 = curvatureTensor[1][1] - curv0*metricTensor[1][1];
		a1 = curv0*metricTensor[0][1] - curvatureTensor[0][1];
		length = Math<Real>::Sqrt(a0*a0 + a1*a1);
		if (length >= Math<Real>::ZERO_TOLERANCE)
		{
			dir0 = a0*derU + a1*derV;
		}
		else
		{
			// Umbilic (surface is locally sphere, any direction principal).
			dir0 = derU;
		}
	}
	dir0.Normalize();

	// Second tangent is cross product of first tangent and normal.
	dir1 = dir0.Cross(normal);
}
Beispiel #7
0
// WARNING: you must ensure that bins_count is big enough
inline static void histogram_helper_cs_RAW_helper_process_pixel_uint16(
    const dt_dev_histogram_collection_params_t *const histogram_params, const uint16_t *pixel, uint32_t *histogram)
{
  const uint16_t i = PU(*pixel, histogram_params);
  histogram[4 * i]++;
}