public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
if (samples <= 0)
return Color.BLACK;
// compute new sample
Color irr = Color.black();
OrthoNormalBasis onb = state.getBasis();
Vector3 w = new Vector3();
int n = state.getDiffuseDepth() == 0 ? samples : 1;
for (int i = 0; i < n; i++)
{
float xi = (float)state.getRandom(i, 0, n);
float xj = (float)state.getRandom(i, 1, n);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
onb.transform(w);
ShadingState temp = state.traceFinalGather(new Ray(state.getPoint(), w), i);
if (temp != null)
{
temp.getInstance().prepareShadingState(temp);
if (temp.getShader() != null)
irr.add(temp.getShader().getRadiance(temp));
}
}
irr.mul((float)Math.PI / n);
return irr;
}
public void getSamples(ShadingState state)
{
if (samples == null)
{
int n = state.getDiffuseDepth() > 0 ? 1 : numSamples;
for (int i = 0; i < n; i++)
{
// random offset on unit square, we use the infinite version of
// getRandom because the light sampling is adaptive
double randX = state.getRandom(i, 0, n);
double randY = state.getRandom(i, 1, n);
int x = 0;
while (randX >= colHistogram[x] && x < colHistogram.Length - 1)
x++;
float[] rowHistogram = imageHistogram[x];
int y = 0;
while (randY >= rowHistogram[y] && y < rowHistogram.Length - 1)
y++;
// sample from (x, y)
float u = (float)((x == 0) ? (randX / colHistogram[0]) : ((randX - colHistogram[x - 1]) / (colHistogram[x] - colHistogram[x - 1])));
float v = (float)((y == 0) ? (randY / rowHistogram[0]) : ((randY - rowHistogram[y - 1]) / (rowHistogram[y] - rowHistogram[y - 1])));
float px = ((x == 0) ? colHistogram[0] : (colHistogram[x] - colHistogram[x - 1]));
float py = ((y == 0) ? rowHistogram[0] : (rowHistogram[y] - rowHistogram[y - 1]));
float su = (x + u) / colHistogram.Length;
float sv = (y + v) / rowHistogram.Length;
float invP = (float)Math.Sin(sv * Math.PI) * jacobian / (n * px * py);
Vector3 dir = getDirection(su, sv);
basis.transform(dir);
if (Vector3.dot(dir, state.getGeoNormal()) > 0)
{
LightSample dest = new LightSample();
dest.setShadowRay(new Ray(state.getPoint(), dir));
dest.getShadowRay().setMax(float.MaxValue);
Color radiance = texture.getPixel(su, sv);
dest.setRadiance(radiance, radiance);
dest.getDiffuseRadiance().mul(invP);
dest.getSpecularRadiance().mul(invP);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
else
{
for (int i = 0; i < numSamples; i++)
{
if (Vector3.dot(samples[i], state.getGeoNormal()) > 0 && Vector3.dot(samples[i], state.getNormal()) > 0)
{
LightSample dest = new LightSample();
dest.setShadowRay(new Ray(state.getPoint(), samples[i]));
dest.getShadowRay().setMax(float.MaxValue);
dest.setRadiance(colors[i], colors[i]);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
}
public void getSamples(ShadingState state)
{
if (Vector3.dot(sunDirWorld, state.getGeoNormal()) > 0 && Vector3.dot(sunDirWorld, state.getNormal()) > 0)
{
LightSample dest = new LightSample();
dest.setShadowRay(new Ray(state.getPoint(), sunDirWorld));
dest.getShadowRay().setMax(float.MaxValue);
dest.setRadiance(sunColor, sunColor);
dest.traceShadow(state);
state.addSample(dest);
}
int n = state.getDiffuseDepth() > 0 ? 1 : numSkySamples;
for (int i = 0; i < n; i++)
{
// random offset on unit square, we use the infinite version of
// getRandom because the light sampling is adaptive
double randX = state.getRandom(i, 0, n);
double randY = state.getRandom(i, 1, n);
int x = 0;
while (randX >= colHistogram[x] && x < colHistogram.Length - 1)
{
x++;
}
float[] rowHistogram = imageHistogram[x];
int y = 0;
while (randY >= rowHistogram[y] && y < rowHistogram.Length - 1)
{
y++;
}
// sample from (x, y)
float u = (float)((x == 0) ? (randX / colHistogram[0]) : ((randX - colHistogram[x - 1]) / (colHistogram[x] - colHistogram[x - 1])));
float v = (float)((y == 0) ? (randY / rowHistogram[0]) : ((randY - rowHistogram[y - 1]) / (rowHistogram[y] - rowHistogram[y - 1])));
float px = ((x == 0) ? colHistogram[0] : (colHistogram[x] - colHistogram[x - 1]));
float py = ((y == 0) ? rowHistogram[0] : (rowHistogram[y] - rowHistogram[y - 1]));
float su = (x + u) / colHistogram.Length;
float sv = (y + v) / rowHistogram.Length;
float invP = (float)Math.Sin(sv * Math.PI) * jacobian / (n * px * py);
Vector3 localDir = getDirection(su, sv);
Vector3 dir = basis.transform(localDir, new Vector3());
if (Vector3.dot(dir, state.getGeoNormal()) > 0 && Vector3.dot(dir, state.getNormal()) > 0)
{
LightSample dest = new LightSample();
dest.setShadowRay(new Ray(state.getPoint(), dir));
dest.getShadowRay().setMax(float.MaxValue);
Color radiance = getSkyRGB(localDir);
dest.setRadiance(radiance, radiance);
dest.getDiffuseRadiance().mul(invP);
dest.getSpecularRadiance().mul(invP);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
public void getSamples(ShadingState state)
{
if (lightBounds.contains(state.getPoint()) && state.getPoint().z < maxZ)
{
int n = state.getDiffuseDepth() > 0 ? 1 : samples;
float a = area / n;
for (int i = 0; i < n; i++)
{
// random offset on unit square, we use the infinite version of
// getRandom
// because the light sampling is adaptive
double randX = state.getRandom(i, 0);
double randY = state.getRandom(i, 1);
Point3 p = new Point3();
p.x = (float)(lxmin * (1 - randX) + lxmax * randX);
p.y = (float)(lymin * (1 - randY) + lymax * randY);
p.z = maxZ - 0.001f;
LightSample dest = new LightSample();
// prepare shadow ray to sampled point
dest.setShadowRay(new Ray(state.getPoint(), p));
// check that the direction of the sample is the same as the
// normal
float cosNx = dest.dot(state.getNormal());
if (cosNx <= 0)
{
return;
}
// light source facing point ?
// (need to check with light source's normal)
float cosNy = dest.getShadowRay().dz;
if (cosNy > 0)
{
// compute geometric attenuation and probability scale
// factor
float r = dest.getShadowRay().getMax();
float g = cosNy / (r * r);
float scale = g * a;
// set sample radiance
dest.setRadiance(radiance, radiance);
dest.getDiffuseRadiance().mul(scale);
dest.getSpecularRadiance().mul(scale);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
}
public void store(ShadingState state, Vector3 dir, Color power, Color diffuse)
{
if (((state.getDiffuseDepth() == 0) && (state.getReflectionDepth() > 0 || state.getRefractionDepth() > 0)))
{
// this is a caustic photon
Photon p = new Photon(state.getPoint(), dir, power);
lock (lockObj)
{
storedPhotons++;
photonList.Add(p);
bounds.include(new Point3(p.x, p.y, p.z));
maxPower = Math.Max(maxPower, power.getMax());
}
}
}
public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
if (samples <= 0)
{
return(Color.BLACK);
}
// compute new sample
Color irr = Color.black();
OrthoNormalBasis onb = state.getBasis();
Vector3 w = new Vector3();
int n = state.getDiffuseDepth() == 0 ? samples : 1;
for (int i = 0; i < n; i++)
{
float xi = (float)state.getRandom(i, 0, n);
float xj = (float)state.getRandom(i, 1, n);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
onb.transform(w);
ShadingState temp = state.traceFinalGather(new Ray(state.getPoint(), w), i);
if (temp != null)
{
temp.getInstance().prepareShadingState(temp);
if (temp.getShader() != null)
{
irr.add(temp.getShader().getRadiance(temp));
}
}
}
irr.mul((float)Math.PI / n);
return(irr);
}
public Color traceRefraction(ShadingState previous, Ray r, int i)
{
// limit path depth and disable caustic paths
if (previous.getRefractionDepth() >= maxRefractionDepth || previous.getDiffuseDepth() > 0)
return Color.BLACK;
IntersectionState istate = previous.getIntersectionState();
istate.numRefractionRays++;
scene.trace(r, istate);
return istate.hit() ? shadeHit(ShadingState.createRefractionBounceState(previous, r, i)) : Color.BLACK;
}
public void traceDiffusePhoton(ShadingState previous, Ray r, Color power)
{
if (previous.getDiffuseDepth() >= maxDiffuseDepth)
return;
IntersectionState istate = previous.getIntersectionState();
scene.trace(r, istate);
if (previous.getIntersectionState().hit())
{
// create a new shading context
ShadingState state = ShadingState.createDiffuseBounceState(previous, r, 0);
shadePhoton(state, power);
}
}
public ShadingState traceFinalGather(ShadingState previous, Ray r, int i)
{
if (previous.getDiffuseDepth() >= maxDiffuseDepth)
return null;
IntersectionState istate = previous.getIntersectionState();
scene.trace(r, istate);
return istate.hit() ? ShadingState.createFinalGatherState(previous, r, i) : null;
}
public void getSamples(ShadingState state)
{
if (getNumSamples() <= 0)
{
return;
}
Vector3 wc = Point3.sub(center, state.getPoint(), new Vector3());
float l2 = wc.LengthSquared();
if (l2 <= r2)
{
return; // inside the sphere?
}
// top of the sphere as viewed from the current shading point
float topX = wc.x + state.getNormal().x *radius;
float topY = wc.y + state.getNormal().y *radius;
float topZ = wc.z + state.getNormal().z *radius;
if (state.getNormal().dot(topX, topY, topZ) <= 0)
{
return; // top of the sphere is below the horizon
}
float cosThetaMax = (float)Math.Sqrt(Math.Max(0, 1 - r2 / Vector3.dot(wc, wc)));
OrthoNormalBasis basis = OrthoNormalBasis.makeFromW(wc);
int samples = state.getDiffuseDepth() > 0 ? 1 : getNumSamples();
float scale = (float)(2 * Math.PI * (1 - cosThetaMax));
Color c = Color.mul(scale / samples, radiance);
for (int i = 0; i < samples; i++)
{
// random offset on unit square
double randX = state.getRandom(i, 0, samples);
double randY = state.getRandom(i, 1, samples);
// cone sampling
double cosTheta = (1 - randX) * cosThetaMax + randX;
double sinTheta = Math.Sqrt(1 - cosTheta * cosTheta);
double phi = randY * 2 * Math.PI;
Vector3 dir = new Vector3((float)(Math.Cos(phi) * sinTheta), (float)(Math.Sin(phi) * sinTheta), (float)cosTheta);
basis.transform(dir);
// check that the direction of the sample is the same as the
// normal
float cosNx = Vector3.dot(dir, state.getNormal());
if (cosNx <= 0)
{
continue;
}
float ocx = state.getPoint().x - center.x;
float ocy = state.getPoint().y - center.y;
float ocz = state.getPoint().z - center.z;
float qa = Vector3.dot(dir, dir);
float qb = 2 * ((dir.x * ocx) + (dir.y * ocy) + (dir.z * ocz));
float qc = ((ocx * ocx) + (ocy * ocy) + (ocz * ocz)) - r2;
double[] t = Solvers.solveQuadric(qa, qb, qc);
if (t == null)
{
continue;
}
LightSample dest = new LightSample();
// compute shadow ray to the sampled point
dest.setShadowRay(new Ray(state.getPoint(), dir));
// FIXME: arbitrary bias, should handle as in other places
dest.getShadowRay().setMax((float)t[0] - 1e-3f);
// prepare sample
dest.setRadiance(c, c);
dest.traceShadow(state);
state.addSample(dest);
}
}
public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
// no gi engine, or we have already exceeded number of available bounces
if (giEngine == null || state.getDiffuseDepth() >= maxDiffuseDepth)
return Color.BLACK;
return giEngine.getIrradiance(state, diffuseReflectance);
}
public void getSamples(ShadingState state)
{
if (meshlight.numSamples == 0)
{
return;
}
Vector3 n = state.getNormal();
Point3 p = state.getPoint();
// vector towards each vertex of the light source
Vector3 p0 = Point3.sub(meshlight.getPoint(meshlight.triangles[tri3 + 0]), p, new Vector3());
// cull triangle if it is facing the wrong way
if (Vector3.dot(p0, ng) >= 0)
{
return;
}
Vector3 p1 = Point3.sub(meshlight.getPoint(meshlight.triangles[tri3 + 1]), p, new Vector3());
Vector3 p2 = Point3.sub(meshlight.getPoint(meshlight.triangles[tri3 + 2]), p, new Vector3());
// if all three vertices are below the hemisphere, stop
if (Vector3.dot(p0, n) <= 0 && Vector3.dot(p1, n) <= 0 && Vector3.dot(p2, n) <= 0)
{
return;
}
p0.normalize();
p1.normalize();
p2.normalize();
float dot = Vector3.dot(p2, p0);
Vector3 h = new Vector3();
h.x = p2.x - dot * p0.x;
h.y = p2.y - dot * p0.y;
h.z = p2.z - dot * p0.z;
float hlen = h.Length();
if (hlen > 1e-6f)
{
h.div(hlen);
}
else
{
return;
}
Vector3 n0 = Vector3.cross(p0, p1, new Vector3());
float len0 = n0.Length();
if (len0 > 1e-6f)
{
n0.div(len0);
}
else
{
return;
}
Vector3 n1 = Vector3.cross(p1, p2, new Vector3());
float len1 = n1.Length();
if (len1 > 1e-6f)
{
n1.div(len1);
}
else
{
return;
}
Vector3 n2 = Vector3.cross(p2, p0, new Vector3());
float len2 = n2.Length();
if (len2 > 1e-6f)
{
n2.div(len2);
}
else
{
return;
}
float cosAlpha = MathUtils.clamp(-Vector3.dot(n2, n0), -1.0f, 1.0f);
float cosBeta = MathUtils.clamp(-Vector3.dot(n0, n1), -1.0f, 1.0f);
float cosGamma = MathUtils.clamp(-Vector3.dot(n1, n2), -1.0f, 1.0f);
float alpha = (float)Math.Acos(cosAlpha);
float beta = (float)Math.Acos(cosBeta);
float gamma = (float)Math.Acos(cosGamma);
float area = alpha + beta + gamma - (float)Math.PI;
float cosC = MathUtils.clamp(Vector3.dot(p0, p1), -1.0f, 1.0f);
float salpha = (float)Math.Sin(alpha);
float product = salpha * cosC;
// use lower sampling depth for diffuse bounces
int samples = state.getDiffuseDepth() > 0 ? 1 : meshlight.numSamples;
Color c = Color.mul(area / samples, meshlight.radiance);
for (int i = 0; i < samples; i++)
{
// random offset on unit square
double randX = state.getRandom(i, 0, samples);
double randY = state.getRandom(i, 1, samples);
float phi = (float)randX * area - alpha + (float)Math.PI;
float sinPhi = (float)Math.Sin(phi);
float cosPhi = (float)Math.Cos(phi);
float u = cosPhi + cosAlpha;
float v = sinPhi - product;
float q = (-v + cosAlpha * (cosPhi * -v + sinPhi * u)) / (salpha * (sinPhi * -v - cosPhi * u));
float q1 = 1.0f - q * q;
if (q1 < 0.0f)
{
q1 = 0.0f;
}
float sqrtq1 = (float)Math.Sqrt(q1);
float ncx = q * p0.x + sqrtq1 * h.x;
float ncy = q * p0.y + sqrtq1 * h.y;
float ncz = q * p0.z + sqrtq1 * h.z;
dot = p1.dot(ncx, ncy, ncz);
float z = 1.0f - (float)randY * (1.0f - dot);
float z1 = 1.0f - z * z;
if (z1 < 0.0f)
{
z1 = 0.0f;
}
Vector3 nd = new Vector3();
nd.x = ncx - dot * p1.x;
nd.y = ncy - dot * p1.y;
nd.z = ncz - dot * p1.z;
nd.normalize();
float sqrtz1 = (float)Math.Sqrt(z1);
Vector3 result = new Vector3();
result.x = z * p1.x + sqrtz1 * nd.x;
result.y = z * p1.y + sqrtz1 * nd.y;
result.z = z * p1.z + sqrtz1 * nd.z;
// make sure the sample is in the right hemisphere - facing in
// the right direction
if (Vector3.dot(result, n) > 0 && Vector3.dot(result, state.getGeoNormal()) > 0 && Vector3.dot(result, ng) < 0)
{
// compute intersection with triangle (if any)
Ray shadowRay = new Ray(state.getPoint(), result);
if (!intersectTriangleKensler(shadowRay))
{
continue;
}
LightSample dest = new LightSample();
dest.setShadowRay(shadowRay);
// prepare sample
dest.setRadiance(c, c);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
public void store(ShadingState state, Vector3 dir, Color power, Color diffuse)
{
if (((state.getDiffuseDepth() == 0) && (state.getReflectionDepth() > 0 || state.getRefractionDepth() > 0)))
{
// this is a caustic photon
Photon p = new Photon(state.getPoint(), dir, power);
lock (lockObj)
{
storedPhotons++;
photonList.Add(p);
bounds.include(new Point3(p.x, p.y, p.z));
maxPower = Math.Max(maxPower, power.getMax());
}
}
}
public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
if (samples <= 0)
return Color.BLACK;
if (state.getDiffuseDepth() > 0)
{
// do simple path tracing for additional bounces (single ray)
float xi = (float)state.getRandom(0, 0, 1);
float xj = (float)state.getRandom(0, 1, 1);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
Vector3 w = new Vector3();
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
OrthoNormalBasis onb = state.getBasis();
onb.transform(w);
Ray r = new Ray(state.getPoint(), w);
ShadingState temp = state.traceFinalGather(r, 0);
return temp != null ? getGlobalRadiance(temp).copy().mul((float)Math.PI) : Color.BLACK;
}
//rwl.readLock().lockwoot();//fixme
Color irr;
lock(lockObj)
irr = getIrradiance(state.getPoint(), state.getNormal());
//rwl.readLock().unlock();
if (irr == null)
{
// compute new sample
irr = Color.black();
OrthoNormalBasis onb = state.getBasis();
float invR = 0;
float minR = float.PositiveInfinity;
Vector3 w = new Vector3();
for (int i = 0; i < samples; i++)
{
float xi = (float)state.getRandom(i, 0, samples);
float xj = (float)state.getRandom(i, 1, samples);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
onb.transform(w);
Ray r = new Ray(state.getPoint(), w);
ShadingState temp = state.traceFinalGather(r, i);
if (temp != null)
{
minR = Math.Min(r.getMax(), minR);
invR += 1.0f / r.getMax();
temp.getInstance().prepareShadingState(temp);
irr.add(getGlobalRadiance(temp));
}
}
irr.mul((float)Math.PI / samples);
invR = samples / invR;
//rwl.writeLock().lockwoot();//fixme
lock(lockObj)
insert(state.getPoint(), state.getNormal(), invR, irr);
//rwl.writeLock().unlock();
// view irr-cache points
// irr = Color.YELLOW.copy().mul(1e6f);
}
return irr;
}
public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
float b = (float)Math.PI * c / diffuseReflectance.getMax();
Color irr = Color.black();
Point3 p = state.getPoint();
Vector3 n = state.getNormal();
int set = (int)(state.getRandom(0, 1, 1) * numSets);
foreach (PointLight vpl in virtualLights[set])
{
Ray r = new Ray(p, vpl.p);
float dotNlD = -(r.dx * vpl.n.x + r.dy * vpl.n.y + r.dz * vpl.n.z);
float dotND = r.dx * n.x + r.dy * n.y + r.dz * n.z;
if (dotNlD > 0 && dotND > 0)
{
float r2 = r.getMax() * r.getMax();
Color opacity = state.traceShadow(r);
Color power = Color.blend(vpl.power, Color.BLACK, opacity);
float g = (dotND * dotNlD) / r2;
irr.madd(0.25f * Math.Min(g, b), power);
}
}
// bias compensation
int nb = (state.getDiffuseDepth() == 0 || numBias <= 0) ? numBias : 1;
if (nb <= 0)
{
return(irr);
}
OrthoNormalBasis onb = state.getBasis();
Vector3 w = new Vector3();
float scale = (float)Math.PI / nb;
for (int i = 0; i < nb; i++)
{
float xi = (float)state.getRandom(i, 0, nb);
float xj = (float)state.getRandom(i, 1, nb);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
onb.transform(w);
Ray r = new Ray(state.getPoint(), w);
r.setMax((float)Math.Sqrt(cosTheta / b));
ShadingState temp = state.traceFinalGather(r, i);
if (temp != null)
{
temp.getInstance().prepareShadingState(temp);
if (temp.getShader() != null)
{
float dist = temp.getRay().getMax();
float r2 = dist * dist;
float cosThetaY = -Vector3.dot(w, temp.getNormal());
if (cosThetaY > 0)
{
float g = (cosTheta * cosThetaY) / r2;
// was this path accounted for yet?
if (g > b)
{
irr.madd(scale * (g - b) / g, temp.getShader().GetRadiance(temp));
}
}
}
}
}
return(irr);
}
public void getSamples(ShadingState state)
{
if (lightBounds.contains(state.getPoint()) && state.getPoint().z < maxZ)
{
int n = state.getDiffuseDepth() > 0 ? 1 : samples;
float a = area / n;
for (int i = 0; i < n; i++)
{
// random offset on unit square
double randX = state.getRandom(i, 0, n);
double randY = state.getRandom(i, 1, n);
Point3 p = new Point3();
p.x = (float)(lxmin * (1 - randX) + lxmax * randX);
p.y = (float)(lymin * (1 - randY) + lymax * randY);
p.z = maxZ - 0.001f;
LightSample dest = new LightSample();
// prepare shadow ray to sampled point
dest.setShadowRay(new Ray(state.getPoint(), p));
// check that the direction of the sample is the same as the
// normal
float cosNx = dest.dot(state.getNormal());
if (cosNx <= 0)
return;
// light source facing point ?
// (need to check with light source's normal)
float cosNy = dest.getShadowRay().dz;
if (cosNy > 0)
{
// compute geometric attenuation and probability scale
// factor
float r = dest.getShadowRay().getMax();
float g = cosNy / (r * r);
float scale = g * a;
// set sample radiance
dest.setRadiance(radiance, radiance);
dest.getDiffuseRadiance().mul(scale);
dest.getSpecularRadiance().mul(scale);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
}
public void getSamples(ShadingState state)
{
if (meshlight.numSamples == 0)
return;
Vector3 n = state.getNormal();
Point3 p = state.getPoint();
// vector towards each vertex of the light source
Vector3 p0 = Point3.sub(meshlight.getPoint(meshlight.triangles[tri3 + 0]), p, new Vector3());
// cull triangle if it is facing the wrong way
if (Vector3.dot(p0, ng) >= 0)
return;
Vector3 p1 = Point3.sub(meshlight.getPoint(meshlight.triangles[tri3 + 1]), p, new Vector3());
Vector3 p2 = Point3.sub(meshlight.getPoint(meshlight.triangles[tri3 + 2]), p, new Vector3());
// if all three vertices are below the hemisphere, stop
if (Vector3.dot(p0, n) <= 0 && Vector3.dot(p1, n) <= 0 && Vector3.dot(p2, n) <= 0)
return;
p0.normalize();
p1.normalize();
p2.normalize();
float dot = Vector3.dot(p2, p0);
Vector3 h = new Vector3();
h.x = p2.x - dot * p0.x;
h.y = p2.y - dot * p0.y;
h.z = p2.z - dot * p0.z;
float hlen = h.Length();
if (hlen > 1e-6f)
h.div(hlen);
else
return;
Vector3 n0 = Vector3.cross(p0, p1, new Vector3());
float len0 = n0.Length();
if (len0 > 1e-6f)
n0.div(len0);
else
return;
Vector3 n1 = Vector3.cross(p1, p2, new Vector3());
float len1 = n1.Length();
if (len1 > 1e-6f)
n1.div(len1);
else
return;
Vector3 n2 = Vector3.cross(p2, p0, new Vector3());
float len2 = n2.Length();
if (len2 > 1e-6f)
n2.div(len2);
else
return;
float cosAlpha = MathUtils.clamp(-Vector3.dot(n2, n0), -1.0f, 1.0f);
float cosBeta = MathUtils.clamp(-Vector3.dot(n0, n1), -1.0f, 1.0f);
float cosGamma = MathUtils.clamp(-Vector3.dot(n1, n2), -1.0f, 1.0f);
float alpha = (float)Math.Acos(cosAlpha);
float beta = (float)Math.Acos(cosBeta);
float gamma = (float)Math.Acos(cosGamma);
float area = alpha + beta + gamma - (float)Math.PI;
float cosC = MathUtils.clamp(Vector3.dot(p0, p1), -1.0f, 1.0f);
float salpha = (float)Math.Sin(alpha);
float product = salpha * cosC;
// use lower sampling depth for diffuse bounces
int samples = state.getDiffuseDepth() > 0 ? 1 : meshlight.numSamples;
Color c = Color.mul(area / samples, meshlight.radiance);
for (int i = 0; i < samples; i++)
{
// random offset on unit square
double randX = state.getRandom(i, 0, samples);
double randY = state.getRandom(i, 1, samples);
float phi = (float)randX * area - alpha + (float)Math.PI;
float sinPhi = (float)Math.Sin(phi);
float cosPhi = (float)Math.Cos(phi);
float u = cosPhi + cosAlpha;
float v = sinPhi - product;
float q = (-v + cosAlpha * (cosPhi * -v + sinPhi * u)) / (salpha * (sinPhi * -v - cosPhi * u));
float q1 = 1.0f - q * q;
if (q1 < 0.0f)
q1 = 0.0f;
float sqrtq1 = (float)Math.Sqrt(q1);
float ncx = q * p0.x + sqrtq1 * h.x;
float ncy = q * p0.y + sqrtq1 * h.y;
float ncz = q * p0.z + sqrtq1 * h.z;
dot = p1.dot(ncx, ncy, ncz);
float z = 1.0f - (float)randY * (1.0f - dot);
float z1 = 1.0f - z * z;
if (z1 < 0.0f)
z1 = 0.0f;
Vector3 nd = new Vector3();
nd.x = ncx - dot * p1.x;
nd.y = ncy - dot * p1.y;
nd.z = ncz - dot * p1.z;
nd.normalize();
float sqrtz1 = (float)Math.Sqrt(z1);
Vector3 result = new Vector3();
result.x = z * p1.x + sqrtz1 * nd.x;
result.y = z * p1.y + sqrtz1 * nd.y;
result.z = z * p1.z + sqrtz1 * nd.z;
// make sure the sample is in the right hemisphere - facing in
// the right direction
if (Vector3.dot(result, n) > 0 && Vector3.dot(result, state.getGeoNormal()) > 0 && Vector3.dot(result, ng) < 0)
{
// compute intersection with triangle (if any)
Ray shadowRay = new Ray(state.getPoint(), result);
if (!intersectTriangleKensler(shadowRay))
continue;
LightSample dest = new LightSample();
dest.setShadowRay(shadowRay);
// prepare sample
dest.setRadiance(c, c);
dest.traceShadow(state);
state.addSample(dest);
}
}
}
public void getSamples(ShadingState state)
{
if (getNumSamples() <= 0)
return;
Vector3 wc = Point3.sub(center, state.getPoint(), new Vector3());
float l2 = wc.LengthSquared();
if (l2 <= r2)
return; // inside the sphere?
// top of the sphere as viewed from the current shading point
float topX = wc.x + state.getNormal().x * radius;
float topY = wc.y + state.getNormal().y * radius;
float topZ = wc.z + state.getNormal().z * radius;
if (state.getNormal().dot(topX, topY, topZ) <= 0)
return; // top of the sphere is below the horizon
float cosThetaMax = (float)Math.Sqrt(Math.Max(0, 1 - r2 / Vector3.dot(wc, wc)));
OrthoNormalBasis basis = OrthoNormalBasis.makeFromW(wc);
int samples = state.getDiffuseDepth() > 0 ? 1 : getNumSamples();
float scale = (float)(2 * Math.PI * (1 - cosThetaMax));
Color c = Color.mul(scale / samples, radiance);
for (int i = 0; i < samples; i++)
{
// random offset on unit square
double randX = state.getRandom(i, 0, samples);
double randY = state.getRandom(i, 1, samples);
// cone sampling
double cosTheta = (1 - randX) * cosThetaMax + randX;
double sinTheta = Math.Sqrt(1 - cosTheta * cosTheta);
double phi = randY * 2 * Math.PI;
Vector3 dir = new Vector3((float)(Math.Cos(phi) * sinTheta), (float)(Math.Sin(phi) * sinTheta), (float)cosTheta);
basis.transform(dir);
// check that the direction of the sample is the same as the
// normal
float cosNx = Vector3.dot(dir, state.getNormal());
if (cosNx <= 0)
continue;
float ocx = state.getPoint().x - center.x;
float ocy = state.getPoint().y - center.y;
float ocz = state.getPoint().z - center.z;
float qa = Vector3.dot(dir, dir);
float qb = 2 * ((dir.x * ocx) + (dir.y * ocy) + (dir.z * ocz));
float qc = ((ocx * ocx) + (ocy * ocy) + (ocz * ocz)) - r2;
double[] t = Solvers.solveQuadric(qa, qb, qc);
if (t == null)
continue;
LightSample dest = new LightSample();
// compute shadow ray to the sampled point
dest.setShadowRay(new Ray(state.getPoint(), dir));
// FIXME: arbitrary bias, should handle as in other places
dest.getShadowRay().setMax((float)t[0] - 1e-3f);
// prepare sample
dest.setRadiance(c, c);
dest.traceShadow(state);
state.addSample(dest);
}
}
public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
if (samples <= 0)
{
return(Color.BLACK);
}
if (state.getDiffuseDepth() > 0)
{
// do simple path tracing for additional bounces (single ray)
float xi = (float)state.getRandom(0, 0, 1);
float xj = (float)state.getRandom(0, 1, 1);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
Vector3 w = new Vector3();
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
OrthoNormalBasis onb = state.getBasis();
onb.transform(w);
Ray r = new Ray(state.getPoint(), w);
ShadingState temp = state.traceFinalGather(r, 0);
return(temp != null?getGlobalRadiance(temp).copy().mul((float)Math.PI) : Color.BLACK);
}
//rwl.readLock().lockwoot();//fixme
Color irr;
lock (lockObj)
irr = getIrradiance(state.getPoint(), state.getNormal());
//rwl.readLock().unlock();
if (irr == null)
{
// compute new sample
irr = Color.black();
OrthoNormalBasis onb = state.getBasis();
float invR = 0;
float minR = float.PositiveInfinity;
Vector3 w = new Vector3();
for (int i = 0; i < samples; i++)
{
float xi = (float)state.getRandom(i, 0, samples);
float xj = (float)state.getRandom(i, 1, samples);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
onb.transform(w);
Ray r = new Ray(state.getPoint(), w);
ShadingState temp = state.traceFinalGather(r, i);
if (temp != null)
{
minR = Math.Min(r.getMax(), minR);
invR += 1.0f / r.getMax();
temp.getInstance().prepareShadingState(temp);
irr.add(getGlobalRadiance(temp));
}
}
irr.mul((float)Math.PI / samples);
invR = samples / invR;
//rwl.writeLock().lockwoot();//fixme
lock (lockObj)
insert(state.getPoint(), state.getNormal(), invR, irr);
//rwl.writeLock().unlock();
// view irr-cache points
// irr = Color.YELLOW.copy().mul(1e6f);
}
return(irr);
}
public Color getIrradiance(ShadingState state, Color diffuseReflectance)
{
float b = (float)Math.PI * c / diffuseReflectance.getMax();
Color irr = Color.black();
Point3 p = state.getPoint();
Vector3 n = state.getNormal();
int set = (int)(state.getRandom(0, 1, 1) * numSets);
foreach (PointLight vpl in virtualLights[set])
{
Ray r = new Ray(p, vpl.p);
float dotNlD = -(r.dx * vpl.n.x + r.dy * vpl.n.y + r.dz * vpl.n.z);
float dotND = r.dx * n.x + r.dy * n.y + r.dz * n.z;
if (dotNlD > 0 && dotND > 0)
{
float r2 = r.getMax() * r.getMax();
Color opacity = state.traceShadow(r);
Color power = Color.blend(vpl.power, Color.BLACK, opacity);
float g = (dotND * dotNlD) / r2;
irr.madd(0.25f * Math.Min(g, b), power);
}
}
// bias compensation
int nb = (state.getDiffuseDepth() == 0 || numBias <= 0) ? numBias : 1;
if (nb <= 0)
return irr;
OrthoNormalBasis onb = state.getBasis();
Vector3 w = new Vector3();
float scale = (float)Math.PI / nb;
for (int i = 0; i < nb; i++)
{
float xi = (float)state.getRandom(i, 0, nb);
float xj = (float)state.getRandom(i, 1, nb);
float phi = (float)(xi * 2 * Math.PI);
float cosPhi = (float)Math.Cos(phi);
float sinPhi = (float)Math.Sin(phi);
float sinTheta = (float)Math.Sqrt(xj);
float cosTheta = (float)Math.Sqrt(1.0f - xj);
w.x = cosPhi * sinTheta;
w.y = sinPhi * sinTheta;
w.z = cosTheta;
onb.transform(w);
Ray r = new Ray(state.getPoint(), w);
r.setMax((float)Math.Sqrt(cosTheta / b));
ShadingState temp = state.traceFinalGather(r, i);
if (temp != null)
{
temp.getInstance().prepareShadingState(temp);
if (temp.getShader() != null)
{
float dist = temp.getRay().getMax();
float r2 = dist * dist;
float cosThetaY = -Vector3.dot(w, temp.getNormal());
if (cosThetaY > 0)
{
float g = (cosTheta * cosThetaY) / r2;
// was this path accounted for yet?
if (g > b)
irr.madd(scale * (g - b) / g, temp.getShader().getRadiance(temp));
}
}
}
}
return irr;
}
