diff options
Diffstat (limited to 'intern/cycles/kernel/kernel_light.h')
| -rw-r--r-- | intern/cycles/kernel/kernel_light.h | 508 |
1 files changed, 7 insertions, 501 deletions
diff --git a/intern/cycles/kernel/kernel_light.h b/intern/cycles/kernel/kernel_light.h index 04472212d0c..138b90373a6 100644 --- a/intern/cycles/kernel/kernel_light.h +++ b/intern/cycles/kernel/kernel_light.h @@ -14,6 +14,8 @@ * limitations under the License. */ +#include "kernel_light_background.h" + CCL_NAMESPACE_BEGIN /* Light Sample result */ @@ -33,500 +35,6 @@ typedef struct LightSample { LightType type; /* type of light */ } LightSample; -/* Area light sampling */ - -/* Uses the following paper: - * - * Carlos Urena et al. - * An Area-Preserving Parametrization for Spherical Rectangles. - * - * https://www.solidangle.com/research/egsr2013_spherical_rectangle.pdf - * - * Note: light_p is modified when sample_coord is true. - */ -ccl_device_inline float rect_light_sample(float3 P, - float3 *light_p, - float3 axisu, - float3 axisv, - float randu, - float randv, - bool sample_coord) -{ - /* In our name system we're using P for the center, - * which is o in the paper. - */ - - float3 corner = *light_p - axisu * 0.5f - axisv * 0.5f; - float axisu_len, axisv_len; - /* Compute local reference system R. */ - float3 x = normalize_len(axisu, &axisu_len); - float3 y = normalize_len(axisv, &axisv_len); - float3 z = cross(x, y); - /* Compute rectangle coords in local reference system. */ - float3 dir = corner - P; - float z0 = dot(dir, z); - /* Flip 'z' to make it point against Q. */ - if (z0 > 0.0f) { - z *= -1.0f; - z0 *= -1.0f; - } - float x0 = dot(dir, x); - float y0 = dot(dir, y); - float x1 = x0 + axisu_len; - float y1 = y0 + axisv_len; - /* Compute internal angles (gamma_i). */ - float4 diff = make_float4(x0, y1, x1, y0) - make_float4(x1, y0, x0, y1); - float4 nz = make_float4(y0, x1, y1, x0) * diff; - nz = nz / sqrt(z0 * z0 * diff * diff + nz * nz); - float g0 = safe_acosf(-nz.x * nz.y); - float g1 = safe_acosf(-nz.y * nz.z); - float g2 = safe_acosf(-nz.z * nz.w); - float g3 = safe_acosf(-nz.w * nz.x); - /* Compute predefined constants. */ - float b0 = nz.x; - float b1 = nz.z; - float b0sq = b0 * b0; - float k = M_2PI_F - g2 - g3; - /* Compute solid angle from internal angles. */ - float S = g0 + g1 - k; - - if (sample_coord) { - /* Compute cu. */ - float au = randu * S + k; - float fu = (cosf(au) * b0 - b1) / sinf(au); - float cu = 1.0f / sqrtf(fu * fu + b0sq) * (fu > 0.0f ? 1.0f : -1.0f); - cu = clamp(cu, -1.0f, 1.0f); - /* Compute xu. */ - float xu = -(cu * z0) / max(sqrtf(1.0f - cu * cu), 1e-7f); - xu = clamp(xu, x0, x1); - /* Compute yv. */ - float z0sq = z0 * z0; - float y0sq = y0 * y0; - float y1sq = y1 * y1; - float d = sqrtf(xu * xu + z0sq); - float h0 = y0 / sqrtf(d * d + y0sq); - float h1 = y1 / sqrtf(d * d + y1sq); - float hv = h0 + randv * (h1 - h0), hv2 = hv * hv; - float yv = (hv2 < 1.0f - 1e-6f) ? (hv * d) / sqrtf(1.0f - hv2) : y1; - - /* Transform (xu, yv, z0) to world coords. */ - *light_p = P + xu * x + yv * y + z0 * z; - } - - /* return pdf */ - if (S != 0.0f) - return 1.0f / S; - else - return 0.0f; -} - -ccl_device_inline float3 ellipse_sample(float3 ru, float3 rv, float randu, float randv) -{ - to_unit_disk(&randu, &randv); - return ru * randu + rv * randv; -} - -ccl_device float3 disk_light_sample(float3 v, float randu, float randv) -{ - float3 ru, rv; - - make_orthonormals(v, &ru, &rv); - - return ellipse_sample(ru, rv, randu, randv); -} - -ccl_device float3 distant_light_sample(float3 D, float radius, float randu, float randv) -{ - return normalize(D + disk_light_sample(D, randu, randv) * radius); -} - -ccl_device float3 -sphere_light_sample(float3 P, float3 center, float radius, float randu, float randv) -{ - return disk_light_sample(normalize(P - center), randu, randv) * radius; -} - -ccl_device float spot_light_attenuation(float3 dir, - float spot_angle, - float spot_smooth, - LightSample *ls) -{ - float3 I = ls->Ng; - - float attenuation = dot(dir, I); - - if (attenuation <= spot_angle) { - attenuation = 0.0f; - } - else { - float t = attenuation - spot_angle; - - if (t < spot_smooth && spot_smooth != 0.0f) - attenuation *= smoothstepf(t / spot_smooth); - } - - return attenuation; -} - -ccl_device float lamp_light_pdf(KernelGlobals *kg, const float3 Ng, const float3 I, float t) -{ - float cos_pi = dot(Ng, I); - - if (cos_pi <= 0.0f) - return 0.0f; - - return t * t / cos_pi; -} - -/* Background Light */ - -#ifdef __BACKGROUND_MIS__ - -ccl_device float3 background_map_sample(KernelGlobals *kg, float randu, float randv, float *pdf) -{ - /* for the following, the CDF values are actually a pair of floats, with the - * function value as X and the actual CDF as Y. The last entry's function - * value is the CDF total. */ - int res_x = kernel_data.integrator.pdf_background_res_x; - int res_y = kernel_data.integrator.pdf_background_res_y; - int cdf_width = res_x + 1; - - /* this is basically std::lower_bound as used by pbrt */ - int first = 0; - int count = res_y; - - while (count > 0) { - int step = count >> 1; - int middle = first + step; - - if (kernel_tex_fetch(__light_background_marginal_cdf, middle).y < randv) { - first = middle + 1; - count -= step + 1; - } - else - count = step; - } - - int index_v = max(0, first - 1); - kernel_assert(index_v >= 0 && index_v < res_y); - - float2 cdf_v = kernel_tex_fetch(__light_background_marginal_cdf, index_v); - float2 cdf_next_v = kernel_tex_fetch(__light_background_marginal_cdf, index_v + 1); - float2 cdf_last_v = kernel_tex_fetch(__light_background_marginal_cdf, res_y); - - /* importance-sampled V direction */ - float dv = inverse_lerp(cdf_v.y, cdf_next_v.y, randv); - float v = (index_v + dv) / res_y; - - /* this is basically std::lower_bound as used by pbrt */ - first = 0; - count = res_x; - while (count > 0) { - int step = count >> 1; - int middle = first + step; - - if (kernel_tex_fetch(__light_background_conditional_cdf, index_v * cdf_width + middle).y < - randu) { - first = middle + 1; - count -= step + 1; - } - else - count = step; - } - - int index_u = max(0, first - 1); - kernel_assert(index_u >= 0 && index_u < res_x); - - float2 cdf_u = kernel_tex_fetch(__light_background_conditional_cdf, - index_v * cdf_width + index_u); - float2 cdf_next_u = kernel_tex_fetch(__light_background_conditional_cdf, - index_v * cdf_width + index_u + 1); - float2 cdf_last_u = kernel_tex_fetch(__light_background_conditional_cdf, - index_v * cdf_width + res_x); - - /* importance-sampled U direction */ - float du = inverse_lerp(cdf_u.y, cdf_next_u.y, randu); - float u = (index_u + du) / res_x; - - /* compute pdf */ - float sin_theta = sinf(M_PI_F * v); - float denom = (M_2PI_F * M_PI_F * sin_theta) * cdf_last_u.x * cdf_last_v.x; - - if (sin_theta == 0.0f || denom == 0.0f) - *pdf = 0.0f; - else - *pdf = (cdf_u.x * cdf_v.x) / denom; - - /* compute direction */ - return equirectangular_to_direction(u, v); -} - -/* TODO(sergey): Same as above, after the release we should consider using - * 'noinline' for all devices. - */ -ccl_device float background_map_pdf(KernelGlobals *kg, float3 direction) -{ - float2 uv = direction_to_equirectangular(direction); - int res_x = kernel_data.integrator.pdf_background_res_x; - int res_y = kernel_data.integrator.pdf_background_res_y; - int cdf_width = res_x + 1; - - float sin_theta = sinf(uv.y * M_PI_F); - - if (sin_theta == 0.0f) - return 0.0f; - - int index_u = clamp(float_to_int(uv.x * res_x), 0, res_x - 1); - int index_v = clamp(float_to_int(uv.y * res_y), 0, res_y - 1); - - /* pdfs in V direction */ - float2 cdf_last_u = kernel_tex_fetch(__light_background_conditional_cdf, - index_v * cdf_width + res_x); - float2 cdf_last_v = kernel_tex_fetch(__light_background_marginal_cdf, res_y); - - float denom = (M_2PI_F * M_PI_F * sin_theta) * cdf_last_u.x * cdf_last_v.x; - - if (denom == 0.0f) - return 0.0f; - - /* pdfs in U direction */ - float2 cdf_u = kernel_tex_fetch(__light_background_conditional_cdf, - index_v * cdf_width + index_u); - float2 cdf_v = kernel_tex_fetch(__light_background_marginal_cdf, index_v); - - return (cdf_u.x * cdf_v.x) / denom; -} - -ccl_device_inline bool background_portal_data_fetch_and_check_side( - KernelGlobals *kg, float3 P, int index, float3 *lightpos, float3 *dir) -{ - int portal = kernel_data.integrator.portal_offset + index; - const ccl_global KernelLight *klight = &kernel_tex_fetch(__lights, portal); - - *lightpos = make_float3(klight->co[0], klight->co[1], klight->co[2]); - *dir = make_float3(klight->area.dir[0], klight->area.dir[1], klight->area.dir[2]); - - /* Check whether portal is on the right side. */ - if (dot(*dir, P - *lightpos) > 1e-4f) - return true; - - return false; -} - -ccl_device_inline float background_portal_pdf( - KernelGlobals *kg, float3 P, float3 direction, int ignore_portal, bool *is_possible) -{ - float portal_pdf = 0.0f; - - int num_possible = 0; - for (int p = 0; p < kernel_data.integrator.num_portals; p++) { - if (p == ignore_portal) - continue; - - float3 lightpos, dir; - if (!background_portal_data_fetch_and_check_side(kg, P, p, &lightpos, &dir)) - continue; - - /* There's a portal that could be sampled from this position. */ - if (is_possible) { - *is_possible = true; - } - num_possible++; - - int portal = kernel_data.integrator.portal_offset + p; - const ccl_global KernelLight *klight = &kernel_tex_fetch(__lights, portal); - float3 axisu = make_float3( - klight->area.axisu[0], klight->area.axisu[1], klight->area.axisu[2]); - float3 axisv = make_float3( - klight->area.axisv[0], klight->area.axisv[1], klight->area.axisv[2]); - bool is_round = (klight->area.invarea < 0.0f); - - if (!ray_quad_intersect(P, - direction, - 1e-4f, - FLT_MAX, - lightpos, - axisu, - axisv, - dir, - NULL, - NULL, - NULL, - NULL, - is_round)) - continue; - - if (is_round) { - float t; - float3 D = normalize_len(lightpos - P, &t); - portal_pdf += fabsf(klight->area.invarea) * lamp_light_pdf(kg, dir, -D, t); - } - else { - portal_pdf += rect_light_sample(P, &lightpos, axisu, axisv, 0.0f, 0.0f, false); - } - } - - if (ignore_portal >= 0) { - /* We have skipped a portal that could be sampled as well. */ - num_possible++; - } - - return (num_possible > 0) ? portal_pdf / num_possible : 0.0f; -} - -ccl_device int background_num_possible_portals(KernelGlobals *kg, float3 P) -{ - int num_possible_portals = 0; - for (int p = 0; p < kernel_data.integrator.num_portals; p++) { - float3 lightpos, dir; - if (background_portal_data_fetch_and_check_side(kg, P, p, &lightpos, &dir)) - num_possible_portals++; - } - return num_possible_portals; -} - -ccl_device float3 background_portal_sample(KernelGlobals *kg, - float3 P, - float randu, - float randv, - int num_possible, - int *sampled_portal, - float *pdf) -{ - /* Pick a portal, then re-normalize randv. */ - randv *= num_possible; - int portal = (int)randv; - randv -= portal; - - /* TODO(sergey): Some smarter way of finding portal to sample - * is welcome. - */ - for (int p = 0; p < kernel_data.integrator.num_portals; p++) { - /* Search for the sampled portal. */ - float3 lightpos, dir; - if (!background_portal_data_fetch_and_check_side(kg, P, p, &lightpos, &dir)) - continue; - - if (portal == 0) { - /* p is the portal to be sampled. */ - int portal = kernel_data.integrator.portal_offset + p; - const ccl_global KernelLight *klight = &kernel_tex_fetch(__lights, portal); - float3 axisu = make_float3( - klight->area.axisu[0], klight->area.axisu[1], klight->area.axisu[2]); - float3 axisv = make_float3( - klight->area.axisv[0], klight->area.axisv[1], klight->area.axisv[2]); - bool is_round = (klight->area.invarea < 0.0f); - - float3 D; - if (is_round) { - lightpos += ellipse_sample(axisu * 0.5f, axisv * 0.5f, randu, randv); - float t; - D = normalize_len(lightpos - P, &t); - *pdf = fabsf(klight->area.invarea) * lamp_light_pdf(kg, dir, -D, t); - } - else { - *pdf = rect_light_sample(P, &lightpos, axisu, axisv, randu, randv, true); - D = normalize(lightpos - P); - } - - *pdf /= num_possible; - *sampled_portal = p; - return D; - } - - portal--; - } - - return make_float3(0.0f, 0.0f, 0.0f); -} - -ccl_device_inline float3 -background_light_sample(KernelGlobals *kg, float3 P, float randu, float randv, float *pdf) -{ - /* Probability of sampling portals instead of the map. */ - float portal_sampling_pdf = kernel_data.integrator.portal_pdf; - - /* Check if there are portals in the scene which we can sample. */ - if (portal_sampling_pdf > 0.0f) { - int num_portals = background_num_possible_portals(kg, P); - if (num_portals > 0) { - if (portal_sampling_pdf == 1.0f || randu < portal_sampling_pdf) { - if (portal_sampling_pdf < 1.0f) { - randu /= portal_sampling_pdf; - } - int portal; - float3 D = background_portal_sample(kg, P, randu, randv, num_portals, &portal, pdf); - if (num_portals > 1) { - /* Ignore the chosen portal, its pdf is already included. */ - *pdf += background_portal_pdf(kg, P, D, portal, NULL); - } - /* We could also have sampled the map, so combine with MIS. */ - if (portal_sampling_pdf < 1.0f) { - float cdf_pdf = background_map_pdf(kg, D); - *pdf = (portal_sampling_pdf * (*pdf) + (1.0f - portal_sampling_pdf) * cdf_pdf); - } - return D; - } - else { - /* Sample map, but with nonzero portal_sampling_pdf for MIS. */ - randu = (randu - portal_sampling_pdf) / (1.0f - portal_sampling_pdf); - } - } - else { - /* We can't sample a portal. - * Check if we can sample the map instead. - */ - if (portal_sampling_pdf == 1.0f) { - /* Use uniform as a fallback if we can't sample the map. */ - *pdf = 1.0f / M_4PI_F; - return sample_uniform_sphere(randu, randv); - } - else { - portal_sampling_pdf = 0.0f; - } - } - } - - float3 D = background_map_sample(kg, randu, randv, pdf); - /* Use MIS if portals could be sampled as well. */ - if (portal_sampling_pdf > 0.0f) { - float portal_pdf = background_portal_pdf(kg, P, D, -1, NULL); - *pdf = (portal_sampling_pdf * portal_pdf + (1.0f - portal_sampling_pdf) * (*pdf)); - } - return D; -} - -ccl_device float background_light_pdf(KernelGlobals *kg, float3 P, float3 direction) -{ - /* Probability of sampling portals instead of the map. */ - float portal_sampling_pdf = kernel_data.integrator.portal_pdf; - - float portal_pdf = 0.0f, map_pdf = 0.0f; - if (portal_sampling_pdf > 0.0f) { - /* Evaluate PDF of sampling this direction by portal sampling. */ - bool is_possible = false; - portal_pdf = background_portal_pdf(kg, P, direction, -1, &is_possible) * portal_sampling_pdf; - if (!is_possible) { - /* Portal sampling is not possible here because all portals point to the wrong side. - * If map sampling is possible, it would be used instead, - * otherwise fallback sampling is used. */ - if (portal_sampling_pdf == 1.0f) { - return kernel_data.integrator.pdf_lights / M_4PI_F; - } - else { - /* Force map sampling. */ - portal_sampling_pdf = 0.0f; - } - } - } - if (portal_sampling_pdf < 1.0f) { - /* Evaluate PDF of sampling this direction by map sampling. */ - map_pdf = background_map_pdf(kg, direction) * (1.0f - portal_sampling_pdf); - } - return (portal_pdf + map_pdf) * kernel_data.integrator.pdf_lights; -} -#endif - /* Regular Light */ ccl_device_inline bool lamp_light_sample( @@ -594,7 +102,7 @@ ccl_device_inline bool lamp_light_sample( /* spot light attenuation */ float3 dir = make_float3(klight->spot.dir[0], klight->spot.dir[1], klight->spot.dir[2]); ls->eval_fac *= spot_light_attenuation( - dir, klight->spot.spot_angle, klight->spot.spot_smooth, ls); + dir, klight->spot.spot_angle, klight->spot.spot_smooth, ls->Ng); if (ls->eval_fac == 0.0f) { return false; } @@ -732,7 +240,7 @@ ccl_device bool lamp_light_eval( /* spot light attenuation */ float3 dir = make_float3(klight->spot.dir[0], klight->spot.dir[1], klight->spot.dir[2]); ls->eval_fac *= spot_light_attenuation( - dir, klight->spot.spot_angle, klight->spot.spot_smooth, ls); + dir, klight->spot.spot_angle, klight->spot.spot_smooth, ls->Ng); if (ls->eval_fac == 0.0f) return false; @@ -805,20 +313,18 @@ ccl_device_inline bool triangle_world_space_vertices( triangle_vertices(kg, prim, V); } -#ifdef __INSTANCING__ if (!(object_flag & SD_OBJECT_TRANSFORM_APPLIED)) { -# ifdef __OBJECT_MOTION__ +#ifdef __OBJECT_MOTION__ float object_time = (time >= 0.0f) ? time : 0.5f; Transform tfm = object_fetch_transform_motion_test(kg, object, object_time, NULL); -# else +#else Transform tfm = object_fetch_transform(kg, object, OBJECT_TRANSFORM); -# endif +#endif V[0] = transform_point(&tfm, V[0]); V[1] = transform_point(&tfm, V[1]); V[2] = transform_point(&tfm, V[2]); has_motion = true; } -#endif return has_motion; } |