1 files changed, 111 insertions, 0 deletions
diff --git a/intern/cycles/kernel/svm/svm_ao.h b/intern/cycles/kernel/svm/svm_ao.h
new file mode 100644
index 00000000000..3f761627e2c
--- /dev/null
+++ b/intern/cycles/kernel/svm/svm_ao.h
@@ -0,0 +1,111 @@
+/*
+* Copyright 2011-2018 Blender Foundation
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+CCL_NAMESPACE_BEGIN
+
+ccl_device_noinline float svm_ao(KernelGlobals *kg,
+                                 ShaderData *sd,
+                                 float3 N,
+                                 ccl_addr_space PathState *state,
+                                 float max_dist,
+                                 int num_samples,
+                                 int flags)
+{
+	if(flags & NODE_AO_GLOBAL_RADIUS) {
+		max_dist = kernel_data.background.ao_distance;
+	}
+
+	/* Early out if no sampling needed. */
+	if(max_dist <= 0.0f || num_samples < 1 || sd->object == OBJECT_NONE) {
+		return 0.0f;
+	}
+
+	if(flags & NODE_AO_INSIDE) {
+		N = -N;
+	}
+
+	float3 T, B;
+	make_orthonormals(N, &T, &B);
+
+	int unoccluded = 0;
+	for(int sample = 0; sample < num_samples; sample++) {
+		float disk_u, disk_v;
+		path_branched_rng_2D(kg, state->rng_hash, state, sample, num_samples,
+		                     PRNG_BEVEL_U, &disk_u, &disk_v);
+
+		float2 d = concentric_sample_disk(disk_u, disk_v);
+		float3 D = make_float3(d.x, d.y, safe_sqrtf(1.0f - dot(d, d)));
+
+		/* Create ray. */
+		Ray ray;
+		ray.P = ray_offset(sd->P, N);
+		ray.D = D.x*T + D.y*B + D.z*N;
+		ray.t = max_dist;
+		ray.time = sd->time;
+
+		if(flags & NODE_AO_ONLY_LOCAL) {
+			if(!scene_intersect_local(kg,
+			                          ray,
+			                          NULL,
+			                          sd->object,
+			                          NULL,
+			                          0)) {
+				unoccluded++;
+			}
+		}
+		else {
+			Intersection isect;
+			if(!scene_intersect(kg,
+			                    ray,
+			                    PATH_RAY_SHADOW_OPAQUE,
+			                    &isect,
+			                    NULL,
+			                    0.0f, 0.0f)) {
+				unoccluded++;
+			}
+		}
+	}
+
+	return ((float) unoccluded) / num_samples;
+}
+
+ccl_device void svm_node_ao(KernelGlobals *kg,
+                            ShaderData *sd,
+                            ccl_addr_space PathState *state,
+                            float *stack,
+                            uint4 node)
+{
+	uint flags, dist_offset, normal_offset, out_ao_offset;
+	decode_node_uchar4(node.y, &flags, &dist_offset, &normal_offset, &out_ao_offset);
+
+	uint color_offset, out_color_offset, samples;
+	decode_node_uchar4(node.z, &color_offset, &out_color_offset, &samples, NULL);
+
+	float dist = stack_load_float_default(stack, dist_offset, node.w);
+	float3 normal = stack_valid(normal_offset)? stack_load_float3(stack, normal_offset): sd->N;
+	float ao = svm_ao(kg, sd, normal, state, dist, samples, flags);
+
+	if (stack_valid(out_ao_offset)) {
+		stack_store_float(stack, out_ao_offset, ao);
+	}
+
+	if (stack_valid(out_color_offset)) {
+		float3 color = stack_load_float3(stack, color_offset);
+		stack_store_float3(stack, out_color_offset, ao * color);
+	}
+}
+
+CCL_NAMESPACE_END