void APerlinNoise2D::GetValue(float x, float y, float * pvValue, int nNumValue)
{
int i, k;
float vx, sx, vy, sy;
int x1, x2, y1, y2;
float value1[3], value2[3];
float valueX1[3], valueX2[3];
float value[3];
float vFinal[3];
memset(vFinal, 0, sizeof(float) * nNumValue);
for(i=0; i<m_nOctaveNum; i++)
{
if( m_nActiveOctave != -1 && m_nActiveOctave != i )
continue;
// Get Horizon interpolated value;
vx = m_nStartPos[i] % m_nBufferWidth + x / m_nWaveLength[i];
x1 = int(vx);
sx = vx - x1;
sx = S_CURVE(sx);
x2 = x1 + 1;
vy = m_nStartPos[i] / m_nBufferWidth + y / m_nWaveLength[i];
y1 = int(vy);
sy = vy - y1;
sy = S_CURVE(sy);
y2 = y1 + 1;
GetRandValues(x1, y1, value1, nNumValue);
GetRandValues(x2, y1, value2, nNumValue);
for(k=0; k<nNumValue; k++)
valueX1[k] = LERP(sx, value1[k], value2[k]);
GetRandValues(x1, y2, value1, nNumValue);
GetRandValues(x2, y2, value2, nNumValue);
for(k=0; k<nNumValue; k++)
valueX2[k] = LERP(sx, value1[k], value2[k]);
if( m_bTurbulence )
{
for(k=0; k<nNumValue; k++)
{
value[k] = (float)fabs(LERP(sy, valueX1[k], valueX2[k]));
vFinal[k] += m_vAmplitude[i] * value[k];
}
}
else
{
for(k=0; k<nNumValue; k++)
{
value[k] = LERP(sy, valueX1[k], valueX2[k]);
vFinal[k] += m_vAmplitude[i] * value[k];
}
}
}
for(k=0; k<nNumValue; k++)
pvValue[k] = vFinal[k];
}
fastf_t
texture_perlin_omega(struct texture_perlin_s *P, vect_t V)
{
vect_t q;
fastf_t r0[3], r1[3], sy, sz, a, b, c, d, t, u, v;
int b0[3], b1[3], b00, b10, b01, b11;
int i, j;
for (i = 0; i < 3; i++) {
t = V[i] + N;
b0[i] = ((int)t) & BM;
b1[i] = (b0[i]+1) & BM;
r0[i] = t - (int)t;
r1[i] = r0[i] - 1.0;
}
i = P->PV[b0[0]];
j = P->PV[b1[0]];
b00 = P->PV[i + b0[1]];
b10 = P->PV[j + b0[1]];
b01 = P->PV[i + b1[1]];
b11 = P->PV[j + b1[1]];
t = S_CURVE(r0[0]);
sy = S_CURVE(r0[1]);
sz = S_CURVE(r0[2]);
VMOVE(q, P->RV[b00 + b0[2]]);
u = AT3(r0[0], r0[1], r0[2]);
VMOVE(q, P->RV[b10 + b0[2]]);
v = AT3(r1[0], r0[1], r0[2]);
a = LERP(t, u, v);
VMOVE(q, P->RV[b01 + b0[2]]);
u = AT3(r0[0], r1[1], r0[2]);
VMOVE(q, P->RV[b11 + b0[2]]);
v = AT3(r1[0], r1[1], r0[2]);
b = LERP(t, u, v);
c = LERP(sy, a, b);
VMOVE(q, P->RV[b00 + b1[2]]);
u = AT3(r0[0], r0[1], r1[2]);
VMOVE(q, P->RV[b10 + b1[2]]);
v = AT3(r1[0], r0[1], r1[2]);
a = LERP(t, u, v);
VMOVE(q, P->RV[b01 + b1[2]]);
u = AT3(r0[0], r1[1], r1[2]);
VMOVE(q, P->RV[b11 + b1[2]]);
v = AT3(r1[0], r1[1], r1[2]);
b = LERP(t, u, v);
d = LERP(sy, a, b);
return LERP(sz, c, d);
}
double
SVGFETurbulenceElement::Noise2(int aColorChannel, double aVec[2],
StitchInfo *aStitchInfo)
{
int bx0, bx1, by0, by1, b00, b10, b01, b11;
double rx0, rx1, ry0, ry1, *q, sx, sy, a, b, t, u, v;
long i, j;
t = aVec[0] + sPerlinN;
bx0 = (int) t;
bx1 = bx0 + 1;
rx0 = t - (int) t;
rx1 = rx0 - 1.0f;
t = aVec[1] + sPerlinN;
by0 = (int) t;
by1 = by0 + 1;
ry0 = t - (int) t;
ry1 = ry0 - 1.0f;
// If stitching, adjust lattice points accordingly.
if (aStitchInfo != NULL) {
if (bx0 >= aStitchInfo->mWrapX)
bx0 -= aStitchInfo->mWidth;
if (bx1 >= aStitchInfo->mWrapX)
bx1 -= aStitchInfo->mWidth;
if (by0 >= aStitchInfo->mWrapY)
by0 -= aStitchInfo->mHeight;
if (by1 >= aStitchInfo->mWrapY)
by1 -= aStitchInfo->mHeight;
}
bx0 &= sBM;
bx1 &= sBM;
by0 &= sBM;
by1 &= sBM;
i = mLatticeSelector[bx0];
j = mLatticeSelector[bx1];
b00 = mLatticeSelector[i + by0];
b10 = mLatticeSelector[j + by0];
b01 = mLatticeSelector[i + by1];
b11 = mLatticeSelector[j + by1];
sx = double (S_CURVE(rx0));
sy = double (S_CURVE(ry0));
q = mGradient[aColorChannel][b00];
u = rx0 * q[0] + ry0 * q[1];
q = mGradient[aColorChannel][b10];
v = rx1 * q[0] + ry0 * q[1];
a = LERP(sx, u, v);
q = mGradient[aColorChannel][b01];
u = rx0 * q[0] + ry1 * q[1];
q = mGradient[aColorChannel][b11];
v = rx1 * q[0] + ry1 * q[1];
b = LERP(sx, u, v);
return LERP(sy, a, b);
}