diff options
author | Brecht Van Lommel <brecht@blender.org> | 2022-02-24 21:40:42 +0300 |
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committer | Brecht Van Lommel <brecht@blender.org> | 2022-02-24 21:40:42 +0300 |
commit | 9de720f31aaa5081dcdd62eee29e67f865d340fc (patch) | |
tree | fea7b16a8f830de116aa9dc67cdf94e1f2df0a27 /intern/cycles | |
parent | 8fb7c50aabdf79d7c0f72a43c624cbbabbe146a7 (diff) | |
parent | 0781c22ceedc6700a073c620723270d32b2f2852 (diff) |
Merge branch 'blender-v3.1-release'
Diffstat (limited to 'intern/cycles')
-rw-r--r-- | intern/cycles/kernel/bvh/util.h | 21 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/init_from_bake.h | 54 | ||||
-rw-r--r-- | intern/cycles/kernel/integrator/shade_surface.h | 6 |
3 files changed, 54 insertions, 27 deletions
diff --git a/intern/cycles/kernel/bvh/util.h b/intern/cycles/kernel/bvh/util.h index 1fd3a3f2850..71045157372 100644 --- a/intern/cycles/kernel/bvh/util.h +++ b/intern/cycles/kernel/bvh/util.h @@ -5,27 +5,6 @@ CCL_NAMESPACE_BEGIN -/* Ray offset to avoid self intersection. - * - * This function should be used to compute a modified ray start position for - * rays leaving from a surface. This is from "A Fast and Robust Method for Avoiding - * Self-Intersection" see https://research.nvidia.com/publication/2019-03_A-Fast-and - */ -ccl_device_inline float3 ray_offset(float3 P, float3 Ng) -{ - const float int_scale = 256.0f; - int3 of_i = make_int3((int)(int_scale * Ng.x), (int)(int_scale * Ng.y), (int)(int_scale * Ng.z)); - - float3 p_i = make_float3(__int_as_float(__float_as_int(P.x) + ((P.x < 0) ? -of_i.x : of_i.x)), - __int_as_float(__float_as_int(P.y) + ((P.y < 0) ? -of_i.y : of_i.y)), - __int_as_float(__float_as_int(P.z) + ((P.z < 0) ? -of_i.z : of_i.z))); - const float origin = 1.0f / 32.0f; - const float float_scale = 1.0f / 65536.0f; - return make_float3(fabsf(P.x) < origin ? P.x + float_scale * Ng.x : p_i.x, - fabsf(P.y) < origin ? P.y + float_scale * Ng.y : p_i.y, - fabsf(P.z) < origin ? P.z + float_scale * Ng.z : p_i.z); -} - #if defined(__KERNEL_CPU__) ccl_device int intersections_compare(const void *a, const void *b) { diff --git a/intern/cycles/kernel/integrator/init_from_bake.h b/intern/cycles/kernel/integrator/init_from_bake.h index e616123e9e7..b84059d6676 100644 --- a/intern/cycles/kernel/integrator/init_from_bake.h +++ b/intern/cycles/kernel/integrator/init_from_bake.h @@ -30,6 +30,50 @@ ccl_device_inline float bake_clamp_mirror_repeat(float u, float max) return ((((int)fu) & 1) ? 1.0f - u : u) * max; } +/* Offset towards center of triangle to avoid ray-tracing precision issues. */ +ccl_device const float2 bake_offset_towards_center(KernelGlobals kg, + const int prim, + const float u, + const float v) +{ + float3 tri_verts[3]; + triangle_vertices(kg, prim, tri_verts); + + /* Empirically determined values, by no means perfect. */ + const float position_offset = 1e-4f; + const float uv_offset = 1e-5f; + + /* Offset position towards center, amount relative to absolute size of position coordinates. */ + const float3 P = u * tri_verts[0] + v * tri_verts[1] + (1.0f - u - v) * tri_verts[2]; + const float3 center = (tri_verts[0] + tri_verts[1] + tri_verts[2]) / 3.0f; + const float3 to_center = center - P; + + const float3 offset_P = P + normalize(to_center) * + min(len(to_center), max(max3(fabs(P)), 1.0f) * position_offset); + + /* Compute barycentric coordinates at new position. */ + const float3 v1 = tri_verts[1] - tri_verts[0]; + const float3 v2 = tri_verts[2] - tri_verts[0]; + const float3 vP = offset_P - tri_verts[0]; + + const float d11 = dot(v1, v1); + const float d12 = dot(v1, v2); + const float d22 = dot(v2, v2); + const float dP1 = dot(vP, v1); + const float dP2 = dot(vP, v2); + + const float denom = d11 * d22 - d12 * d12; + if (denom == 0.0f) { + return make_float2(0.0f, 0.0f); + } + + const float offset_v = clamp((d22 * dP1 - d12 * dP2) / denom, uv_offset, 1.0f - uv_offset); + const float offset_w = clamp((d11 * dP2 - d12 * dP1) / denom, uv_offset, 1.0f - uv_offset); + const float offset_u = clamp(1.0f - offset_v - offset_w, uv_offset, 1.0f - uv_offset); + + return make_float2(offset_u, offset_v); +} + /* Return false to indicate that this pixel is finished. * Used by CPU implementation to not attempt to sample pixel for multiple samples once its known * that the pixel did converge. */ @@ -87,7 +131,7 @@ ccl_device bool integrator_init_from_bake(KernelGlobals kg, /* Initialize path state for path integration. */ path_state_init_integrator(kg, state, sample, rng_hash); - /* Barycentric UV with sub-pixel offset. */ + /* Barycentric UV. */ float u = primitive[2]; float v = primitive[3]; @@ -96,6 +140,14 @@ ccl_device bool integrator_init_from_bake(KernelGlobals kg, float dvdx = differential[2]; float dvdy = differential[3]; + /* Exactly at vertex? Nudge inwards to avoid self-intersection. */ + if ((u == 0.0f || u == 1.0f) && (v == 0.0f || v == 1.0f)) { + const float2 uv = bake_offset_towards_center(kg, prim, u, v); + u = uv.x; + v = uv.y; + } + + /* Sub-pixel offset. */ if (sample > 0) { u = bake_clamp_mirror_repeat(u + dudx * (filter_x - 0.5f) + dudy * (filter_y - 0.5f), 1.0f); v = bake_clamp_mirror_repeat(v + dvdx * (filter_x - 0.5f) + dvdy * (filter_y - 0.5f), diff --git a/intern/cycles/kernel/integrator/shade_surface.h b/intern/cycles/kernel/integrator/shade_surface.h index f548d91031d..d2442755646 100644 --- a/intern/cycles/kernel/integrator/shade_surface.h +++ b/intern/cycles/kernel/integrator/shade_surface.h @@ -352,12 +352,8 @@ ccl_device_forceinline void integrate_surface_ao(KernelGlobals kg, float ao_pdf; sample_cos_hemisphere(ao_N, bsdf_u, bsdf_v, &ao_D, &ao_pdf); - if (!(dot(sd->Ng, ao_D) > 0.0f && ao_pdf != 0.0f)) { - return; - } - Ray ray ccl_optional_struct_init; - ray.P = sd->P; + ray.P = shadow_ray_offset(kg, sd, ao_D); ray.D = ao_D; ray.t = kernel_data.integrator.ao_bounces_distance; ray.time = sd->time; |