Cycles: Restructure kernel files organization

Since the kernel split work we're now having quite a few of new files, majority
of which are related on the kernel entry points. Keeping those files in the
root kernel folder will eventually make it really hard to follow which files are
actual implementation of Cycles kernel.

Those files are now moved to kernel/kernels/<device_type>. This way adding extra
entry points will be less noisy. It is also nice to have all device-specific
files grouped together.

Another change is in the way how split kernel invokes logic. Previously all the
logic was implemented directly in the .cl files, which makes it a bit tricky to
re-use the logic across other devices. Since we'll likely be looking into doing
same split work for CUDA devices eventually it makes sense to move logic from
.cl files to header files. Those files are stored in kernel/split. This does not
mean the header files will not give error messages when tried to be included
from other devices and their arguments will likely be changed, but having such
separation is a good start anyway.

There should be no functional changes.

Reviewers: juicyfruit, dingto

Differential Revision: https://developer.blender.org/D1314

1 files changed, 400 insertions, 0 deletions

diff --git a/intern/cycles/kernel/split/kernel_data_init.h b/intern/cycles/kernel/split/kernel_data_init.h
new file mode 100644
index 00000000000..b7a4d847d03
--- /dev/null
+++ b/intern/cycles/kernel/split/kernel_data_init.h
@@ -0,0 +1,400 @@
+/*
+ * Copyright 2011-2015 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.
+ */
+
+#include "kernel_split_common.h"
+
+/*
+ * Note on kernel_data_initialization kernel
+ * This kernel Initializes structures needed in path-iteration kernels.
+ * This is the first kernel in ray-tracing logic.
+ *
+ * Ray state of rays outside the tile-boundary will be marked RAY_INACTIVE
+ *
+ * Its input and output are as follows,
+ *
+ * Un-initialized rng---------------|--- kernel_data_initialization ---|--- Initialized rng
+ * Un-initialized throughput -------|                                  |--- Initialized throughput
+ * Un-initialized L_transparent ----|                                  |--- Initialized L_transparent
+ * Un-initialized PathRadiance -----|                                  |--- Initialized PathRadiance
+ * Un-initialized Ray --------------|                                  |--- Initialized Ray
+ * Un-initialized PathState --------|                                  |--- Initialized PathState
+ * Un-initialized QueueData --------|                                  |--- Initialized QueueData (to QUEUE_EMPTY_SLOT)
+ * Un-initilaized QueueIndex -------|                                  |--- Initialized QueueIndex (to 0)
+ * Un-initialized use_queues_flag---|                                  |--- Initialized use_queues_flag (to false)
+ * Un-initialized ray_state --------|                                  |--- Initialized ray_state
+ * parallel_samples --------------- |                                  |--- Initialized per_sample_output_buffers
+ * rng_state -----------------------|                                  |--- Initialized work_array
+ * data ----------------------------|                                  |--- Initialized work_pool_wgs
+ * start_sample --------------------|                                  |
+ * sx ------------------------------|                                  |
+ * sy ------------------------------|                                  |
+ * sw ------------------------------|                                  |
+ * sh ------------------------------|                                  |
+ * stride --------------------------|                                  |
+ * queuesize -----------------------|                                  |
+ * num_samples ---------------------|                                  |
+ *
+ * Note on Queues :
+ * All slots in queues are initialized to queue empty slot;
+ * The number of elements in the queues is initialized to 0;
+ */
+ccl_device void kernel_data_init(
+	ccl_global char *globals,
+	ccl_global char *shader_data_sd,                  /* Arguments related to ShaderData */
+	ccl_global char *shader_data_sd_DL_shadow,     /* Arguments related to ShaderData */
+
+	ccl_global float3 *P_sd,
+	ccl_global float3 *P_sd_DL_shadow,
+
+	ccl_global float3 *N_sd,
+	ccl_global float3 *N_sd_DL_shadow,
+
+	ccl_global float3 *Ng_sd,
+	ccl_global float3 *Ng_sd_DL_shadow,
+
+	ccl_global float3 *I_sd,
+	ccl_global float3 *I_sd_DL_shadow,
+
+	ccl_global int *shader_sd,
+	ccl_global int *shader_sd_DL_shadow,
+
+	ccl_global int *flag_sd,
+	ccl_global int *flag_sd_DL_shadow,
+
+	ccl_global int *prim_sd,
+	ccl_global int *prim_sd_DL_shadow,
+
+	ccl_global int *type_sd,
+	ccl_global int *type_sd_DL_shadow,
+
+	ccl_global float *u_sd,
+	ccl_global float *u_sd_DL_shadow,
+
+	ccl_global float *v_sd,
+	ccl_global float *v_sd_DL_shadow,
+
+	ccl_global int *object_sd,
+	ccl_global int *object_sd_DL_shadow,
+
+	ccl_global float *time_sd,
+	ccl_global float *time_sd_DL_shadow,
+
+	ccl_global float *ray_length_sd,
+	ccl_global float *ray_length_sd_DL_shadow,
+
+	ccl_global int *ray_depth_sd,
+	ccl_global int *ray_depth_sd_DL_shadow,
+
+	ccl_global int *transparent_depth_sd,
+	ccl_global int *transparent_depth_sd_DL_shadow,
+
+	/* Ray differentials. */
+	ccl_global differential3 *dP_sd,
+	ccl_global differential3 *dP_sd_DL_shadow,
+
+	ccl_global differential3 *dI_sd,
+	ccl_global differential3 *dI_sd_DL_shadow,
+
+	ccl_global differential *du_sd,
+	ccl_global differential *du_sd_DL_shadow,
+
+	ccl_global differential *dv_sd,
+	ccl_global differential *dv_sd_DL_shadow,
+
+	/* Dp/Du */
+	ccl_global float3 *dPdu_sd,
+	ccl_global float3 *dPdu_sd_DL_shadow,
+
+	ccl_global float3 *dPdv_sd,
+	ccl_global float3 *dPdv_sd_DL_shadow,
+
+	/* Object motion. */
+	ccl_global Transform *ob_tfm_sd,
+	ccl_global Transform *ob_tfm_sd_DL_shadow,
+
+	ccl_global Transform *ob_itfm_sd,
+	ccl_global Transform *ob_itfm_sd_DL_shadow,
+
+	ShaderClosure *closure_sd,
+	ShaderClosure *closure_sd_DL_shadow,
+
+	ccl_global int *num_closure_sd,
+	ccl_global int *num_closure_sd_DL_shadow,
+
+	ccl_global float *randb_closure_sd,
+	ccl_global float *randb_closure_sd_DL_shadow,
+
+	ccl_global float3 *ray_P_sd,
+	ccl_global float3 *ray_P_sd_DL_shadow,
+
+	ccl_global differential3 *ray_dP_sd,
+	ccl_global differential3 *ray_dP_sd_DL_shadow,
+
+	ccl_constant KernelData *data,
+	ccl_global float *per_sample_output_buffers,
+	ccl_global uint *rng_state,
+	ccl_global uint *rng_coop,                   /* rng array to store rng values for all rays */
+	ccl_global float3 *throughput_coop,          /* throughput array to store throughput values for all rays */
+	ccl_global float *L_transparent_coop,        /* L_transparent array to store L_transparent values for all rays */
+	PathRadiance *PathRadiance_coop,  /* PathRadiance array to store PathRadiance values for all rays */
+	ccl_global Ray *Ray_coop,                    /* Ray array to store Ray information for all rays */
+	ccl_global PathState *PathState_coop,        /* PathState array to store PathState information for all rays */
+	ccl_global char *ray_state,                  /* Stores information on current state of a ray */
+
+#define KERNEL_TEX(type, ttype, name) \
+	ccl_global type *name,
+#include "../kernel_textures.h"
+
+	int start_sample, int sx, int sy, int sw, int sh, int offset, int stride,
+	int rng_state_offset_x,
+	int rng_state_offset_y,
+	int rng_state_stride,
+	ccl_global int *Queue_data,                  /* Memory for queues */
+	ccl_global int *Queue_index,                 /* Tracks the number of elements in queues */
+	int queuesize,                               /* size (capacity) of the queue */
+	ccl_global char *use_queues_flag,            /* flag to decide if scene-intersect kernel should use queues to fetch ray index */
+	ccl_global unsigned int *work_array,         /* work array to store which work each ray belongs to */
+#ifdef __WORK_STEALING__
+	ccl_global unsigned int *work_pool_wgs,      /* Work pool for each work group */
+	unsigned int num_samples,                    /* Total number of samples per pixel */
+#endif
+#ifdef __KERNEL_DEBUG__
+	DebugData *debugdata_coop,
+#endif
+	int parallel_samples                         /* Number of samples to be processed in parallel */
+	)
+{
+
+	/* Load kernel globals structure */
+	KernelGlobals *kg = (KernelGlobals *)globals;
+
+	kg->data = data;
+#define KERNEL_TEX(type, ttype, name) \
+	kg->name = name;
+#include "../kernel_textures.h"
+
+	/* Load ShaderData structure */
+	ShaderData *sd = (ShaderData *)shader_data_sd;
+	ShaderData *sd_DL_shadow = (ShaderData *)shader_data_sd_DL_shadow;
+
+	sd->P = P_sd;
+	sd_DL_shadow->P = P_sd_DL_shadow;
+
+	sd->N = N_sd;
+	sd_DL_shadow->N = N_sd_DL_shadow;
+
+	sd->Ng = Ng_sd;
+	sd_DL_shadow->Ng = Ng_sd_DL_shadow;
+
+	sd->I = I_sd;
+	sd_DL_shadow->I = I_sd_DL_shadow;
+
+	sd->shader = shader_sd;
+	sd_DL_shadow->shader = shader_sd_DL_shadow;
+
+	sd->flag = flag_sd;
+	sd_DL_shadow->flag = flag_sd_DL_shadow;
+
+	sd->prim = prim_sd;
+	sd_DL_shadow->prim = prim_sd_DL_shadow;
+
+	sd->type = type_sd;
+	sd_DL_shadow->type = type_sd_DL_shadow;
+
+	sd->u = u_sd;
+	sd_DL_shadow->u = u_sd_DL_shadow;
+
+	sd->v = v_sd;
+	sd_DL_shadow->v = v_sd_DL_shadow;
+
+	sd->object = object_sd;
+	sd_DL_shadow->object = object_sd_DL_shadow;
+
+	sd->time = time_sd;
+	sd_DL_shadow->time = time_sd_DL_shadow;
+
+	sd->ray_length = ray_length_sd;
+	sd_DL_shadow->ray_length = ray_length_sd_DL_shadow;
+
+	sd->ray_depth = ray_depth_sd;
+	sd_DL_shadow->ray_depth = ray_depth_sd_DL_shadow;
+
+	sd->transparent_depth = transparent_depth_sd;
+	sd_DL_shadow->transparent_depth = transparent_depth_sd_DL_shadow;
+
+#ifdef __RAY_DIFFERENTIALS__
+	sd->dP = dP_sd;
+	sd_DL_shadow->dP = dP_sd_DL_shadow;
+
+	sd->dI = dI_sd;
+	sd_DL_shadow->dI = dI_sd_DL_shadow;
+
+	sd->du = du_sd;
+	sd_DL_shadow->du = du_sd_DL_shadow;
+
+	sd->dv = dv_sd;
+	sd_DL_shadow->dv = dv_sd_DL_shadow;
+#ifdef __DPDU__
+	sd->dPdu = dPdu_sd;
+	sd_DL_shadow->dPdu = dPdu_sd_DL_shadow;
+
+	sd->dPdv = dPdv_sd;
+	sd_DL_shadow->dPdv = dPdv_sd_DL_shadow;
+#endif
+#endif
+
+#ifdef __OBJECT_MOTION__
+	sd->ob_tfm = ob_tfm_sd;
+	sd_DL_shadow->ob_tfm = ob_tfm_sd_DL_shadow;
+
+	sd->ob_itfm = ob_itfm_sd;
+	sd_DL_shadow->ob_itfm = ob_itfm_sd_DL_shadow;
+#endif
+
+	sd->closure = closure_sd;
+	sd_DL_shadow->closure = closure_sd_DL_shadow;
+
+	sd->num_closure = num_closure_sd;
+	sd_DL_shadow->num_closure = num_closure_sd_DL_shadow;
+
+	sd->randb_closure = randb_closure_sd;
+	sd_DL_shadow->randb_closure = randb_closure_sd_DL_shadow;
+
+	sd->ray_P = ray_P_sd;
+	sd_DL_shadow->ray_P = ray_P_sd_DL_shadow;
+
+	sd->ray_dP = ray_dP_sd;
+	sd_DL_shadow->ray_dP = ray_dP_sd_DL_shadow;
+
+	int thread_index = get_global_id(1) * get_global_size(0) + get_global_id(0);
+
+#ifdef __WORK_STEALING__
+	int lid = get_local_id(1) * get_local_size(0) + get_local_id(0);
+	/* Initialize work_pool_wgs */
+	if(lid == 0) {
+		int group_index = get_group_id(1) * get_num_groups(0) + get_group_id(0);
+		work_pool_wgs[group_index] = 0;
+	}
+	barrier(CLK_LOCAL_MEM_FENCE);
+#endif // __WORK_STEALING__
+
+	/* Initialize queue data and queue index */
+	if(thread_index < queuesize) {
+		/* Initialize active ray queue */
+		Queue_data[QUEUE_ACTIVE_AND_REGENERATED_RAYS * queuesize + thread_index] = QUEUE_EMPTY_SLOT;
+		/* Initialize background and buffer update queue */
+		Queue_data[QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS * queuesize + thread_index] = QUEUE_EMPTY_SLOT;
+		/* Initialize shadow ray cast of AO queue */
+		Queue_data[QUEUE_SHADOW_RAY_CAST_AO_RAYS * queuesize + thread_index] = QUEUE_EMPTY_SLOT;
+		/* Initialize shadow ray cast of direct lighting queue */
+		Queue_data[QUEUE_SHADOW_RAY_CAST_DL_RAYS * queuesize + thread_index] = QUEUE_EMPTY_SLOT;
+	}
+
+	if(thread_index == 0) {
+		Queue_index[QUEUE_ACTIVE_AND_REGENERATED_RAYS] = 0;
+		Queue_index[QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS] = 0;
+		Queue_index[QUEUE_SHADOW_RAY_CAST_AO_RAYS] = 0;
+		Queue_index[QUEUE_SHADOW_RAY_CAST_DL_RAYS] = 0;
+		/* The scene-intersect kernel should not use the queues very first time.
+		 * since the queue would be empty.
+		 */
+		use_queues_flag[0] = 0;
+	}
+
+	int x = get_global_id(0);
+	int y = get_global_id(1);
+
+	if(x < (sw * parallel_samples) && y < sh) {
+
+		int ray_index = x + y * (sw * parallel_samples);
+
+		/* This is the first assignment to ray_state; So we dont use ASSIGN_RAY_STATE macro */
+		ray_state[ray_index] = RAY_ACTIVE;
+
+		unsigned int my_sample;
+		unsigned int pixel_x;
+		unsigned int pixel_y;
+		unsigned int tile_x;
+		unsigned int tile_y;
+		unsigned int my_sample_tile;
+
+#ifdef __WORK_STEALING__
+		unsigned int my_work = 0;
+		/* get work */
+		get_next_work(work_pool_wgs, &my_work, sw, sh, num_samples, parallel_samples, ray_index);
+		/* Get the sample associated with the work */
+		my_sample = get_my_sample(my_work, sw, sh, parallel_samples, ray_index) + start_sample;
+
+		my_sample_tile = 0;
+
+		/* Get pixel and tile position associated with the work */
+		get_pixel_tile_position(&pixel_x, &pixel_y, &tile_x, &tile_y, my_work, sw, sh, sx, sy, parallel_samples, ray_index);
+		work_array[ray_index] = my_work;
+#else // __WORK_STEALING__
+
+		unsigned int tile_index = ray_index / parallel_samples;
+		tile_x = tile_index % sw;
+		tile_y = tile_index / sw;
+		my_sample_tile = ray_index - (tile_index * parallel_samples);
+		my_sample = my_sample_tile + start_sample;
+
+		/* Initialize work array */
+		work_array[ray_index] = my_sample ;
+
+		/* Calculate pixel position of this ray */
+		pixel_x = sx + tile_x;
+		pixel_y = sy + tile_y;
+#endif // __WORK_STEALING__
+
+		rng_state += (rng_state_offset_x + tile_x) + (rng_state_offset_y + tile_y) * rng_state_stride;
+
+		/* Initialise per_sample_output_buffers to all zeros */
+		per_sample_output_buffers += (((tile_x + (tile_y * stride)) * parallel_samples) + (my_sample_tile)) * kernel_data.film.pass_stride;
+		int per_sample_output_buffers_iterator = 0;
+		for(per_sample_output_buffers_iterator = 0; per_sample_output_buffers_iterator < kernel_data.film.pass_stride; per_sample_output_buffers_iterator++) {
+			per_sample_output_buffers[per_sample_output_buffers_iterator] = 0.0f;
+		}
+
+		/* initialize random numbers and ray */
+		kernel_path_trace_setup(kg, rng_state, my_sample, pixel_x, pixel_y, &rng_coop[ray_index], &Ray_coop[ray_index]);
+
+		if(Ray_coop[ray_index].t != 0.0f) {
+			/* Initialize throuput, L_transparent, Ray, PathState; These rays proceed with path-iteration*/
+			throughput_coop[ray_index] = make_float3(1.0f, 1.0f, 1.0f);
+			L_transparent_coop[ray_index] = 0.0f;
+			path_radiance_init(&PathRadiance_coop[ray_index], kernel_data.film.use_light_pass);
+			path_state_init(kg, &PathState_coop[ray_index], &rng_coop[ray_index], my_sample, &Ray_coop[ray_index]);
+#ifdef __KERNEL_DEBUG__
+			debug_data_init(&debugdata_coop[ray_index]);
+#endif
+		} else {
+			/*These rays do not participate in path-iteration */
+
+			float4 L_rad = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
+			/* accumulate result in output buffer */
+			kernel_write_pass_float4(per_sample_output_buffers, my_sample, L_rad);
+			path_rng_end(kg, rng_state, rng_coop[ray_index]);
+
+			ASSIGN_RAY_STATE(ray_state, ray_index, RAY_TO_REGENERATE);
+		}
+	}
+
+	/* Mark rest of the ray-state indices as RAY_INACTIVE */
+	if(thread_index < (get_global_size(0) * get_global_size(1)) - (sh * (sw * parallel_samples))) {
+		/* First assignment, hence we dont use ASSIGN_RAY_STATE macro */
+		ray_state[((sw * parallel_samples) * sh) + thread_index] = RAY_INACTIVE;
+	}
+}