diff options
Diffstat (limited to 'intern/cycles/kernel/closure/volume.h')
| -rw-r--r-- | intern/cycles/kernel/closure/volume.h | 84 |
1 files changed, 31 insertions, 53 deletions
diff --git a/intern/cycles/kernel/closure/volume.h b/intern/cycles/kernel/closure/volume.h index 6e24b60af39..9dbb5154457 100644 --- a/intern/cycles/kernel/closure/volume.h +++ b/intern/cycles/kernel/closure/volume.h @@ -7,7 +7,7 @@ CCL_NAMESPACE_BEGIN /* VOLUME EXTINCTION */ -ccl_device void volume_extinction_setup(ccl_private ShaderData *sd, float3 weight) +ccl_device void volume_extinction_setup(ccl_private ShaderData *sd, Spectrum weight) { if (sd->flag & SD_EXTINCTION) { sd->closure_transparent_extinction += weight; @@ -48,10 +48,10 @@ ccl_device int volume_henyey_greenstein_setup(ccl_private HenyeyGreensteinVolume return SD_SCATTER; } -ccl_device float3 volume_henyey_greenstein_eval_phase(ccl_private const ShaderVolumeClosure *svc, - const float3 I, - float3 omega_in, - ccl_private float *pdf) +ccl_device Spectrum volume_henyey_greenstein_eval_phase(ccl_private const ShaderVolumeClosure *svc, + const float3 I, + float3 omega_in, + ccl_private float *pdf) { float g = svc->g; @@ -64,7 +64,7 @@ ccl_device float3 volume_henyey_greenstein_eval_phase(ccl_private const ShaderVo *pdf = single_peaked_henyey_greenstein(cos_theta, g); } - return make_float3(*pdf, *pdf, *pdf); + return make_spectrum(*pdf); } ccl_device float3 @@ -101,37 +101,27 @@ henyey_greenstrein_sample(float3 D, float g, float randu, float randv, ccl_priva ccl_device int volume_henyey_greenstein_sample(ccl_private const ShaderVolumeClosure *svc, float3 I, - float3 dIdx, - float3 dIdy, float randu, float randv, - ccl_private float3 *eval, + ccl_private Spectrum *eval, ccl_private float3 *omega_in, - ccl_private float3 *domega_in_dx, - ccl_private float3 *domega_in_dy, ccl_private float *pdf) { float g = svc->g; /* note that I points towards the viewer and so is used negated */ *omega_in = henyey_greenstrein_sample(-I, g, randu, randv, pdf); - *eval = make_float3(*pdf, *pdf, *pdf); /* perfect importance sampling */ - -#ifdef __RAY_DIFFERENTIALS__ - /* todo: implement ray differential estimation */ - *domega_in_dx = make_float3(0.0f, 0.0f, 0.0f); - *domega_in_dy = make_float3(0.0f, 0.0f, 0.0f); -#endif + *eval = make_spectrum(*pdf); /* perfect importance sampling */ return LABEL_VOLUME_SCATTER; } /* VOLUME CLOSURE */ -ccl_device float3 volume_phase_eval(ccl_private const ShaderData *sd, - ccl_private const ShaderVolumeClosure *svc, - float3 omega_in, - ccl_private float *pdf) +ccl_device Spectrum volume_phase_eval(ccl_private const ShaderData *sd, + ccl_private const ShaderVolumeClosure *svc, + float3 omega_in, + ccl_private float *pdf) { return volume_henyey_greenstein_eval_phase(svc, sd->I, omega_in, pdf); } @@ -140,22 +130,11 @@ ccl_device int volume_phase_sample(ccl_private const ShaderData *sd, ccl_private const ShaderVolumeClosure *svc, float randu, float randv, - ccl_private float3 *eval, + ccl_private Spectrum *eval, ccl_private float3 *omega_in, - ccl_private differential3 *domega_in, ccl_private float *pdf) { - return volume_henyey_greenstein_sample(svc, - sd->I, - sd->dI.dx, - sd->dI.dy, - randu, - randv, - eval, - omega_in, - &domega_in->dx, - &domega_in->dy, - pdf); + return volume_henyey_greenstein_sample(svc, sd->I, randu, randv, eval, omega_in, pdf); } /* Volume sampling utilities. */ @@ -164,45 +143,44 @@ ccl_device int volume_phase_sample(ccl_private const ShaderData *sd, * unnecessary work in volumes and subsurface scattering. */ #define VOLUME_THROUGHPUT_EPSILON 1e-6f -ccl_device float3 volume_color_transmittance(float3 sigma, float t) +ccl_device Spectrum volume_color_transmittance(Spectrum sigma, float t) { - return exp3(-sigma * t); + return exp(-sigma * t); } -ccl_device float volume_channel_get(float3 value, int channel) +ccl_device float volume_channel_get(Spectrum value, int channel) { - return (channel == 0) ? value.x : ((channel == 1) ? value.y : value.z); + return GET_SPECTRUM_CHANNEL(value, channel); } -ccl_device int volume_sample_channel(float3 albedo, - float3 throughput, +ccl_device int volume_sample_channel(Spectrum albedo, + Spectrum throughput, float rand, - ccl_private float3 *pdf) + ccl_private Spectrum *pdf) { /* Sample color channel proportional to throughput and single scattering * albedo, to significantly reduce noise with many bounce, following: * * "Practical and Controllable Subsurface Scattering for Production Path * Tracing". Matt Jen-Yuan Chiang, Peter Kutz, Brent Burley. SIGGRAPH 2016. */ - float3 weights = fabs(throughput * albedo); - float sum_weights = weights.x + weights.y + weights.z; + Spectrum weights = fabs(throughput * albedo); + float sum_weights = reduce_add(weights); if (sum_weights > 0.0f) { *pdf = weights / sum_weights; } else { - *pdf = make_float3(1.0f / 3.0f, 1.0f / 3.0f, 1.0f / 3.0f); + *pdf = make_spectrum(1.0f / SPECTRUM_CHANNELS); } - if (rand < pdf->x) { - return 0; - } - else if (rand < pdf->x + pdf->y) { - return 1; - } - else { - return 2; + float pdf_sum = 0.0f; + FOREACH_SPECTRUM_CHANNEL (i) { + pdf_sum += GET_SPECTRUM_CHANNEL(*pdf, i); + if (rand < pdf_sum) { + return i; + } } + return SPECTRUM_CHANNELS - 1; } CCL_NAMESPACE_END |