bool LightScheme::GetLightIter(TracingInstance* pLocalData, const KVec2& samplePos, UINT32 lightIdx, const ShadingContext* shadingCtx, const IntersectContext* hit_ctx, LightIterator& out_iter) const
{
const ILightObject* pLightObj = GetLightPtr(lightIdx);
KVec3 lightPos_f;
KVec3d lightPos;
KColor litClr;
if (pLightObj->EvaluateLighting(samplePos, shadingCtx->position, lightPos_f, out_iter)) {
lightPos = ToVec3d(lightPos_f);
bool isOccluded = false;
KColor transmission(out_iter.intensity);
{
KVec3d adjustedPos = ToVec3d(shadingCtx->position);
KVec3d lightDir = lightPos - adjustedPos;
float l_n = ToVec3f(lightDir) * shadingCtx->normal;
float l_fn = ToVec3f(lightDir) * shadingCtx->face_normal;
if (l_n > 0 && l_fn < 0)
AdjustHitPos(pLocalData, *hit_ctx, *shadingCtx, adjustedPos);
KVec3d temp_light_pos(lightPos);
lightDir = adjustedPos - temp_light_pos;
KRay ray;
lightDir = temp_light_pos - adjustedPos;
ray.Init(adjustedPos, lightDir, NULL);
ray.mExcludeBBoxNode = hit_ctx->bbox_node_idx;
ray.mExcludeTriID = hit_ctx->tri_id;
KColor trans_coefficent;
pLocalData->ComputeLightTransimission(ray, 1.0f, trans_coefficent);
transmission.Modulate(trans_coefficent);
}
if (transmission.Luminance() > 0) {
out_iter.intensity = transmission;
return true;
}
}
return false;
}
bool LightScheme::GetLightIter(TracingInstance* pLocalData, const KVec2& samplePos, UINT32 lightIdx, const ShadingContext* shadingCtx, const IntersectContext* hit_ctx, LightIterator& out_iter) const
{
const ILightObject* pLightObj = GetLightPtr(lightIdx);
KVec3 lightPos_f;
KVec3d lightPos;
KColor litClr;
if (pLightObj->EvaluateLighting(samplePos, shadingCtx->position, lightPos_f, out_iter)) {
lightPos = ToVec3d(lightPos_f);
bool isOccluded = false;
KColor transmission(out_iter.intensity);
{
KVec3d adjustedPos = ToVec3d(shadingCtx->position);
KVec3d lightDir = lightPos - adjustedPos;
float l_n = ToVec3f(lightDir) * shadingCtx->normal;
float l_fn = ToVec3f(lightDir) * shadingCtx->face_normal;
if (l_n > 0) {
if (l_fn < 0)
AdjustHitPos(pLocalData, *hit_ctx, *shadingCtx, adjustedPos);
KVec3d temp_light_pos(lightPos);
lightDir = adjustedPos - temp_light_pos;
// Clamp the shadow ray if the light source is out of the scene's bounding box.
// Doing so can improve the floating point precision.
const KBBox& sceneBBox = pLocalData->GetScenePtr()->GetSceneBBox();
bool needClampRay = !sceneBBox.IsInside(ToVec3f(temp_light_pos));
if (needClampRay) {
KRay ray;
ray.Init(temp_light_pos, lightDir, NULL);
double t0, t1;
if (IntersectBBox(ray, sceneBBox, t0, t1)) {
temp_light_pos = ray.GetOrg() + ray.GetDir() * t0;
}
}
KRay ray;
lightDir = adjustedPos - temp_light_pos;
ray.Init(temp_light_pos, lightDir, NULL);
ray.mExcludeBBoxNode = INVALID_INDEX;
ray.mExcludeTriID = INVALID_INDEX;
float lum = 1.0f;
while (lum > 0) {
IntersectContext test_ctx;
test_ctx.ray_t = 1.0;
isOccluded = pLocalData->CastRay(ray, test_ctx);
if (isOccluded) {
if (test_ctx.bbox_node_idx == hit_ctx->bbox_node_idx && test_ctx.tri_id == hit_ctx->tri_id)
break;
// Calculate how much light can pass through the hit surface
KColor temp_trans;
ShadingContext shading_context;
pLocalData->CalcuShadingContext(ray, test_ctx, shading_context);
TransContext& transCtx = pLocalData->GetCurrentTransCtxStorage();
pLocalData->ConvertToTransContext(test_ctx, shading_context, transCtx);
shading_context.surface_shader->ShaderTransmission(transCtx, temp_trans);
transmission.Modulate(temp_trans);
lum = transmission.Luminance();
if (lum > 0.001f) {
KVec3d go_dis = lightDir*test_ctx.ray_t;
temp_light_pos += (go_dis * 1.00001);
lightDir -= (go_dis * 0.9999);
ray.Init(temp_light_pos, lightDir, NULL);
ray.mExcludeBBoxNode = test_ctx.bbox_node_idx;
ray.mExcludeTriID = test_ctx.tri_id;
}
else {
transmission.Clear();
break;
}
}
else
break;
}
}
else
transmission.Clear();
}
if (transmission.Luminance() > 0) {
out_iter.intensity = transmission;
return true;
}
}
return false;
}