def UniformSampleOneLight(scene: Scene, renderer: Renderer, p: Point3d, n: Normal, wo: Vector3d,
time: float, bsdf: BSDF, sample: Sample,
lightSampleOffsets: [LightSampleOffsets]=None, bsdfSampleOffsets: [BSDFSampleOffsets]=None,
lightNumOffset: int=-1) -> Spectrum:
L = Spectrum(0.0)
nLights = int(len(scene.lights))
if nLights == 0:
return Spectrum(0.0)
if lightNumOffset != -1:
lightNum = int((sample.values_array_1d[lightNumOffset][0] * nLights)) # todo floor to int
else:
lightNum = int((random() * nLights)) # todo floor to int
lightNum = min(lightNum, nLights - 1)
light = scene.lights[lightNum]
# Initialize light and bsdf samples for single light sample
if lightSampleOffsets is not None and bsdfSampleOffsets is not None:
lightSample = LightSample.create_from_sample(sample, lightSampleOffsets, 0)
bsdfSample = BSDFSample.create_from_sample(sample, bsdfSampleOffsets, 0)
else:
lightSample = LightSample.create_from_random()
bsdfSample = BSDFSample.create_from_random()
Ld = EstimateDirect(scene, renderer, light, p, n, wo, time, bsdf, lightSample, bsdfSample,
BxDFType.BSDF_ALL & ~BxDFType.BSDF_SPECULAR)
return Ld * float(nLights)
def UniformSampleAllLights(scene: Scene, renderer: Renderer, p: Point3d, n: Normal, wo: Vector3d,
time: float, bsdf: BSDF, sample: Sample,
lightSampleOffsets: [LightSampleOffsets],
bsdfSampleOffsets: [BSDFSampleOffsets]) -> Spectrum:
L = Spectrum(0.0)
for i in range(len(scene.lights)):
light = scene.lights[i]
if lightSampleOffsets is None:
nSamples = 1
else:
nSamples = lightSampleOffsets[i].nSamples
# Estimate direct lighting from _light_ samples
Ld = Spectrum(0.0)
for j in range(nSamples):
# Find light and BSDF sample values for direct lighting estimate
if lightSampleOffsets is not None and bsdfSampleOffsets is not None:
lightSample = LightSample.create_from_sample(sample, lightSampleOffsets[i], j)
bsdfSample = BSDFSample.create_from_sample(sample, bsdfSampleOffsets[i], j)
else:
lightSample = LightSample.create_from_random()
bsdfSample = BSDFSample.create_from_random()
Ld += EstimateDirect(scene, renderer, light, p, n, wo, time, bsdf, lightSample, bsdfSample,
BxDFType.BSDF_ALL & ~BxDFType.BSDF_SPECULAR)
L += Ld / nSamples
return L
