static void
trace_pixel(ri_vector_t *radiance, int x, int y)
{
unsigned char type;
double bsdf[3];
ri_ray_t ray;
ri_intersection_state_t state;
pathnode_t node;
ri_vector_t Le;
/* first check a ray hits scene object through pixel (x, y) */
ri_vector_copy(&ray.org, cam_pos);
sample_pixel(&ray.dir, x, y);
ray.thread_num = 0;
if (!ri_raytrace(ri_render_get(), &ray, &state)) {
/* hits background */
ri_texture_ibl_fetch(radiance, light->texture, ray.dir);
return;
}
node.depth = 2;
node.G[0] = 1.0; node.G[1] = 1.0; node.G[2] = 1.0;
ri_mem_copy(&node.state, &state, sizeof(ri_intersection_state_t));
ri_vector_copy(&node.indir, ray.dir);
// assume that the camera is not located in the transparent object
node.interior = 0;
trace_path(&node);
/* connect the path to the IBL light source */
type = sample_reflection_type(node.state.geom->material);
//if (node.interior) printf("???\n");
sample_outdir(&ray.dir, &type,
node.interior,
node.state.geom->material,
node.indir, node.state.Ng);
brdf(bsdf,
type, &node.state,
node.indir, ray.dir, node.state.Ng);
node.G[0] *= bsdf[0];
node.G[1] *= bsdf[1];
node.G[2] *= bsdf[2];
ri_vector_copy(&ray.org, node.state.P);
light_sample(&Le, ray.org, ray.dir);
radiance->f[0] = Le.f[0] * node.G[0];
radiance->f[1] = Le.f[1] * node.G[1];
radiance->f[2] = Le.f[2] * node.G[2];
}
void do_lum(t_obj *obc, t_cod *cor, t_sph *obj_hit, double omeg)
{
obc->bounce -= 80;
if (obc->bri)
{
normalize(cor->n);
normalize(cor->l_x);
brdf(cor, obj_hit, obc, omeg);
}
}
void alsIrradiateSample(
VR::VRayContext &rc,
DirectionalMessageData *dmd,
const VR::Color &diffuse
)
{
if (dmd->sss_depth >= SSS_MAX_SAMPLES)
return;
//void *orig_op;
//AiStateGetMsgPtr("als_sss_op", &orig_op);
//
//int als_context = ALS_CONTEXT_NONE;
//AiStateGetMsgInt("als_context", &als_context);
//AtRay ray;
//AtScrSample scrs;
// There are a few contexts in which we can be called here:
// 1) Intersecting same object with same shader
// 2) Intersecting same object with different shader
// 3) Intersecting different object with same shader
// 4) Intersecting different object with different shader
// 5) Called from an indirect ray from another shader while tracing for SSS
// 2 and 4 could possibly be because we're running from a layer shader. if we try to evaluate in that context we will simply crash
// 5 will cause fireflies so we need to detect this and return
// just return if this is a different object.
// More elaborate checks may be needed; see VRayFastSSS2 source, considerPointForSSS().
if (rc.parent && rc.rayresult.sb != rc.parent->rayresult.sb)
{
return;
}
// if we're in a layered context and running a different shader from the one that's tracing for sss, just return to let the other shader handle it
//if (als_context == ALS_CONTEXT_LAYER && (dmd->shader_orig != sg->shader))
//{
// return;
//}
DiffusionSample& samp = dmd->samples[dmd->sss_depth];
samp.S = (rc.rayresult.wpoint - dmd->Po);
samp.r = VR::length(samp.S);
samp.Rd.set(0.0f, 0.0f, 0.0f);
// The original alSurface line below seems wrong, but looks like has no effect on Arnold;
// we probably only want to subtract just the distance from the previous SSS hit to this one.
// In the V-Ray version, I'm using the fact that the direction along the SSS ray is a unit
// one, so I can just use the hit ray coefficient.
// dmd->maxdist -= samp.r;
dmd->maxdist -= float(rc.rayresult.wpointCoeff-rc.rayparams.mint);
// if we're not using trace sets to explicitly define what objects we want to trace against, then assume we only want to trace against ourselves
// or if we're not doing sss in this shader, just continue the ray
/*
if ((!trace_set_enabled && orig_op != sg->Op) || sssMix == 0.0f)
{
if (dmd->sss_depth < SSS_MAX_SAMPLES && dmd->maxdist > 0.0f)
{
AiMakeRay(&ray, AI_RAY_SUBSURFACE, &sg->P, &sg->Rd, dmd->maxdist, sg);
AiTrace(&ray, &scrs);
}
return;
}*/
// AiStateSetMsgInt("als_raytype", ALS_RAY_UNDEFINED);
// assert(sg->P != dmd->Po);
// put normals the right way round
VR::Vector Nref = rc.rayresult.normal;
matchNormals(Nref, rc.rayresult.gnormal);
matchNormals(Nref, rc.rayresult.origNormal);
// void* brdf_data = AiOrenNayarMISCreateData(sg, 0.0f);
// AiLightsPrepare(sg);
VR::Color result_direct(0.0f, 0.0f, 0.0f);
VR::Color Rnond(0.0f, 0.0f, 0.0f);
bool directional = dmd->directional;
// In V-Ray, always compute dipole diffuse reflectance; we use this as approximation
// when V-Ray needs to know the diffuse surface color.
for (int c = 0; c < dmd->numComponents; ++c)
{
Rnond += directionalDipole(rc.rayresult.wpoint, rc.rayresult.normal, dmd->Po, dmd->No, rc.rayresult.normal, dmd->No, dmd->sp[c]) * dmd->weights[c];
}
// Calculate the direct lighting.
ALSIrradiateBRDF brdf(dmd, Rnond, samp, diffuse);
result_direct=rc.vray->getSequenceData().directLightManager->eval(rc, brdf);
/*
while (AiLightsGetSample(sg))
{
// get the group assigned to this light from the hash table using the light's pointer
int lightGroup = lightGroupMap[sg->Lp];
float diffuse_strength = AiLightGetDiffuse(sg->Lp);
// Does not using MIS here get us anything?
// AtRGB L = AiEvaluateLightSample(sg, brdf_data, AiOrenNayarMISSample, AiOrenNayarMISBRDF, AiOrenNayarMISPDF);
VR::Color L = sg->Li * VR::Max(VR::dotf(sg->Ld, sg->N), 0.0f) * (1.0f/VR::pi()) * sg->we * diffuse_strength;
if (L.isBlack()) continue;
if (directional)
{
VR::Color R(0.0f, 0.0f, 0.0f);
for (int c=0; c < dmd->numComponents; ++c)
{
if (samp.r < dmd->sp[c].safe_radius)
R += directionalDipole(sg->P, sg->N, dmd->Po, dmd->No, sg->N, dmd->No, dmd->sp[c]) * dmd->weights[c];
else
R += directionalDipole(sg->P, sg->N, dmd->Po, dmd->No, sg->Ld, dmd->wo, dmd->sp[c]) * dmd->weights[c];
}
L *= R;
result_direct += L;
vassert(VR::fastfinite(result_direct.sum()));
}
else
{
L *= Rnond;
result_direct += L;
vassert(VR::fastfinite(result_direct.sum()));
}
}*/
// Calculate the indirect lighting if GI in V-Ray is enabled.
VR::Color result_indirect(0.0f, 0.0f, 0.0f);
if (rc.vray->getSequenceData().params.gi.indirectOn) {
VR::Vector U, V;
VR::computeTangentVectors(rc.rayresult.normal, U, V);
VR::VRayContext &nrc=rc.newSpawnContext(0, VR::Color(1.0f, 1.0f, 1.0f), VR::RT_INDIRECT | VR::RT_ENVIRONMENT, rc.rayresult.gnormal);
for (int i=0; i<1; i++)
{
float samples[2];
samples[0]=nrc.getDMCValue();
samples[1]=nrc.getDMCValue();
float stheta = sqrtf(float(samples[0]));
float phi = float(VR::pi()*2.0f * samples[1]);
VR::Vector dir;
dir.x = stheta * cosf(phi);
dir.y = stheta * sinf(phi);
float cs=sqrtf(VR::Max(0.0f, 1.0f - float(samples[0])));
dir.z = cs;
dir=dir.x*U+dir.y*V+dir.z*rc.rayresult.normal;
nrc.setTracedDir(dir);
nrc.rayparams.rayProbability=2.0f*cs;
VR::Color giColor=nrc.traceCurrentRay();
VR::Color f;
if (directional)
{
VR::Color R(0.0f, 0.0f, 0.0f);
for (int c = 0; c < dmd->numComponents; ++c)
{
R += directionalDipole(rc.rayresult.wpoint, rc.rayresult.normal, dmd->Po, dmd->No, dir, dmd->wo, dmd->sp[c]) * dmd->weights[c];
}
f = R;
result_indirect += giColor * R;
vassert(VR::fastfinite(result_indirect.sum()));
}
else
{
f = Rnond;
result_indirect += giColor * Rnond;
vassert(VR::fastfinite(result_indirect.sum()));
}
}
nrc.releaseContext();
}
// TODO: this is guaranteed to be 1 in every case, right?
// result_indirect *= AiSamplerGetSampleInvCount(sampit);
samp.Rd = result_direct + result_indirect;
vassert(VR::fastfinite(samp.Rd.sum()));
samp.N = rc.rayresult.normal;
samp.Ng = rc.rayresult.gnormal;
samp.P = rc.rayresult.wpoint;
dmd->sss_depth++;
//AiStateSetMsgInt("als_raytype", ALS_RAY_SSS);
//
//if (dmd->sss_depth < SSS_MAX_SAMPLES && dmd->maxdist > 0.0f)
//{
//
// AiMakeRay(&ray, AI_RAY_SUBSURFACE, &sg->P, &sg->Rd, dmd->maxdist, sg);
// AiTrace(&ray, &scrs);
//}
}
static int
trace_path(pathnode_t *path)
{
unsigned char type; /* type of reflection */
int hit;
int prev_interior;
double bsdf[3];
ri_vector_t outdir;
ri_ray_t ray;
ri_intersection_state_t next_state;
ri_material_t *material;
if (path->depth >= MAX_PATH_VERTICES) {
return 0;
}
material = path->state.geom->material;
if (!russian_roulette(material)) {
return 0;
}
type = sample_reflection_type(material);
prev_interior = path->interior;
if (path->interior && !floateq(material->ior, 1.0f)) {
/* ray exits from a transparent object */
path->interior = 0;
}
sample_outdir(&outdir, &type,
path->interior, material,
path->indir, path->state.Ng);
if (type == 'T' && prev_interior) {
/* ray enters into a transparent object */
path->interior = 1;
}
/* find next surface point where ray hits */
ri_vector_copy(&ray.org, path->state.P);
ri_vector_copy(&ray.dir, outdir);
ray.thread_num = 0;
hit = ri_raytrace(ri_render_get(), &ray, &next_state);
if (!hit) {
return 0;
}
brdf(bsdf,
type, &path->state,
path->indir, outdir, path->state.Ng);
path->G[0] *= bsdf[0];
path->G[1] *= bsdf[1];
path->G[2] *= bsdf[2];
path->depth++;
ri_vector_copy(&path->indir, outdir);
//ri_vector_neg(&path->indir);
ri_mem_copy(&path->state, &next_state, sizeof(ri_intersection_state_t));
return trace_path(path);
}