Cycles: Cleanup, wipe obviously outdated parts of split kernel comments

12 files changed, 114 insertions, 336 deletions

diff --git a/intern/cycles/kernel/split/kernel_buffer_update.h b/intern/cycles/kernel/split/kernel_buffer_update.h
index e42605c88e7..e8f574c5546 100644
--- a/intern/cycles/kernel/split/kernel_buffer_update.h
+++ b/intern/cycles/kernel/split/kernel_buffer_update.h
@@ -16,58 +16,27 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_background_buffer_update kernel.
- * This is the fourth kernel in the ray tracing logic, and the third
- * of the path iteration kernels. This kernel takes care of rays that hit
- * the background (sceneintersect kernel), and for the rays of
- * state RAY_UPDATE_BUFFER it updates the ray's accumulated radiance in
- * the output buffer. This kernel also takes care of rays that have been determined
- * to-be-regenerated.
+/* This kernel takes care of rays that hit the background (sceneintersect
+ * kernel), and for the rays of state RAY_UPDATE_BUFFER it updates the ray's
+ * accumulated radiance in the output buffer. This kernel also takes care of
+ * rays that have been determined to-be-regenerated.
  *
- * We will empty QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue in this kernel
+ * We will empty QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue in this kernel.
  *
  * Typically all rays that are in state RAY_HIT_BACKGROUND, RAY_UPDATE_BUFFER
- * will be eventually set to RAY_TO_REGENERATE state in this kernel. Finally all rays of ray_state
- * RAY_TO_REGENERATE will be regenerated and put in queue QUEUE_ACTIVE_AND_REGENERATED_RAYS.
+ * will be eventually set to RAY_TO_REGENERATE state in this kernel.
+ * Finally all rays of ray_state RAY_TO_REGENERATE will be regenerated and put
+ * in queue QUEUE_ACTIVE_AND_REGENERATED_RAYS.
  *
- * The input and output are as follows,
- *
- * rng_coop ---------------------------------------------|--- kernel_background_buffer_update --|--- PathRadiance_coop
- * throughput_coop --------------------------------------|                                      |--- L_transparent_coop
- * per_sample_output_buffers ----------------------------|                                      |--- per_sample_output_buffers
- * Ray_coop ---------------------------------------------|                                      |--- ray_state
- * PathState_coop ---------------------------------------|                                      |--- Queue_data (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * L_transparent_coop -----------------------------------|                                      |--- Queue_data (QUEUE_ACTIVE_AND_REGENERATED_RAYS)
- * ray_state --------------------------------------------|                                      |--- Queue_index (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * Queue_data (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS) ----|                                      |--- Queue_index (QUEUE_ACTIVE_AND_REGENERATED_RAYS)
- * Queue_index (QUEUE_ACTIVE_AND_REGENERATED_RAYS) ------|                                      |--- work_array
- * parallel_samples -------------------------------------|                                      |--- PathState_coop
- * end_sample -------------------------------------------|                                      |--- throughput_coop
- * kg (globals) -----------------------------------------|                                      |--- rng_coop
- * rng_state --------------------------------------------|                                      |--- Ray
- * PathRadiance_coop ------------------------------------|                                      |
- * sw ---------------------------------------------------|                                      |
- * sh ---------------------------------------------------|                                      |
- * sx ---------------------------------------------------|                                      |
- * sy ---------------------------------------------------|                                      |
- * stride -----------------------------------------------|                                      |
- * work_array -------------------------------------------|                                      |--- work_array
- * queuesize --------------------------------------------|                                      |
- * start_sample -----------------------------------------|                                      |--- work_pool_wgs
- * work_pool_wgs ----------------------------------------|                                      |
- * num_samples ------------------------------------------|                                      |
- *
- * note on sd : sd argument is neither an input nor an output for this kernel. It is just filled and consumed here itself.
- * Note on Queues :
- * This kernel fetches rays from QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue.
- *
- * State of queues when this kernel is called :
+ * State of queues when this kernel is called:
  * At entry,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE rays
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_UPDATE_BUFFER, RAY_HIT_BACKGROUND, RAY_TO_REGENERATE rays
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE rays.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with
+ *     RAY_UPDATE_BUFFER, RAY_HIT_BACKGROUND, RAY_TO_REGENERATE rays.
  * At exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE and RAY_REGENERATED rays
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be empty
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE and
+ *     RAY_REGENERATED rays.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be empty.
  */
 ccl_device void kernel_buffer_update(KernelGlobals *kg)
 {
@@ -225,4 +194,3 @@ ccl_device void kernel_buffer_update(KernelGlobals *kg)
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_data_init.h b/intern/cycles/kernel/split/kernel_data_init.h
index 9b62d65ffd9..ed447049e48 100644
--- a/intern/cycles/kernel/split/kernel_data_init.h
+++ b/intern/cycles/kernel/split/kernel_data_init.h
@@ -16,16 +16,16 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_data_initialization kernel
- * This kernel Initializes structures needed in path-iteration kernels.
+/* This kernel Initializes structures needed in path-iteration kernels.
  *
- * Note on Queues :
+ * Note on Queues:
  * All slots in queues are initialized to queue empty slot;
  * The number of elements in the queues is initialized to 0;
  */
 
-/* distributes an amount of work across all threads
- * note: work done inside the loop may not show up to all threads till after the current kernel has completed
+/* Distributes an amount of work across all threads
+ * note: work done inside the loop may not show up to all threads till after
+ * the current kernel has completed
  */
 #define parallel_for(kg, iter_name, work_size) \
 	for(size_t _size = (work_size), \
@@ -151,4 +151,3 @@ void KERNEL_FUNCTION_FULL_NAME(data_init)(
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_direct_lighting.h b/intern/cycles/kernel/split/kernel_direct_lighting.h
index 5163b8edc04..dfe461fb357 100644
--- a/intern/cycles/kernel/split/kernel_direct_lighting.h
+++ b/intern/cycles/kernel/split/kernel_direct_lighting.h
@@ -16,36 +16,29 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_direct_lighting kernel.
- * This is the eighth kernel in the ray tracing logic. This is the seventh
- * of the path iteration kernels. This kernel takes care of direct lighting
- * logic. However, the "shadow ray cast" part of direct lighting is handled
+/* This kernel takes care of direct lighting logic.
+ * However, the "shadow ray cast" part of direct lighting is handled
  * in the next kernel.
  *
- * This kernels determines the rays for which a shadow_blocked() function associated with direct lighting should be executed.
- * Those rays for which a shadow_blocked() function for direct-lighting must be executed, are marked with flag RAY_SHADOW_RAY_CAST_DL and
- * enqueued into the queue QUEUE_SHADOW_RAY_CAST_DL_RAYS
+ * This kernels determines the rays for which a shadow_blocked() function
+ * associated with direct lighting should be executed. Those rays for which
+ * a shadow_blocked() function for direct-lighting must be executed, are
+ * marked with flag RAY_SHADOW_RAY_CAST_DL and enqueued into the queue
+ * QUEUE_SHADOW_RAY_CAST_DL_RAYS
  *
- * The input and output are as follows,
+ * Note on Queues:
+ * This kernel only reads from the QUEUE_ACTIVE_AND_REGENERATED_RAYS queue
+ * and processes only the rays of state RAY_ACTIVE; If a ray needs to execute
+ * the corresponding shadow_blocked part, after direct lighting, the ray is
+ * marked with RAY_SHADOW_RAY_CAST_DL flag.
  *
- * rng_coop -----------------------------------------|--- kernel_direct_lighting --|--- BSDFEval_coop
- * PathState_coop -----------------------------------|                             |--- ISLamp_coop
- * sd -----------------------------------------------|                             |--- LightRay_coop
- * ray_state ----------------------------------------|                             |--- ray_state
- * Queue_data (QUEUE_ACTIVE_AND_REGENERATED_RAYS) ---|                             |
- * kg (globals) -------------------------------------|                             |
- * queuesize ----------------------------------------|                             |
- *
- * Note on Queues :
- * This kernel only reads from the QUEUE_ACTIVE_AND_REGENERATED_RAYS queue and processes
- * only the rays of state RAY_ACTIVE; If a ray needs to execute the corresponding shadow_blocked
- * part, after direct lighting, the ray is marked with RAY_SHADOW_RAY_CAST_DL flag.
- *
- * State of queues when this kernel is called :
- * state of queues QUEUE_ACTIVE_AND_REGENERATED_RAYS and QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be same
- * before and after this kernel call.
- * QUEUE_SHADOW_RAY_CAST_DL_RAYS queue will be filled with rays for which a shadow_blocked function must be executed, after this
- * kernel call. Before this kernel call the QUEUE_SHADOW_RAY_CAST_DL_RAYS will be empty.
+ * State of queues when this kernel is called:
+ * - State of queues QUEUE_ACTIVE_AND_REGENERATED_RAYS and
+ *   QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be same before and after this
+ *   kernel call.
+ * - QUEUE_SHADOW_RAY_CAST_DL_RAYS queue will be filled with rays for which a
+ *   shadow_blocked function must be executed, after this kernel call
+ *    Before this kernel call the QUEUE_SHADOW_RAY_CAST_DL_RAYS will be empty.
  */
 ccl_device void kernel_direct_lighting(KernelGlobals *kg)
 {
diff --git a/intern/cycles/kernel/split/kernel_holdout_emission_blurring_pathtermination_ao.h b/intern/cycles/kernel/split/kernel_holdout_emission_blurring_pathtermination_ao.h
index 7168efa59ae..bb948ad24b0 100644
--- a/intern/cycles/kernel/split/kernel_holdout_emission_blurring_pathtermination_ao.h
+++ b/intern/cycles/kernel/split/kernel_holdout_emission_blurring_pathtermination_ao.h
@@ -16,59 +16,41 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_holdout_emission_blurring_pathtermination_ao kernel.
- * This is the sixth kernel in the ray tracing logic. This is the fifth
- * of the path iteration kernels. This kernel takes care of the logic to process
- * "material of type holdout", indirect primitive emission, bsdf blurring,
- * probabilistic path termination and AO.
+/* This kernel takes care of the logic to process "material of type holdout",
+ * indirect primitive emission, bsdf blurring, probabilistic path termination
+ * and AO.
  *
- * This kernels determines the rays for which a shadow_blocked() function associated with AO should be executed.
- * Those rays for which a shadow_blocked() function for AO must be executed are marked with flag RAY_SHADOW_RAY_CAST_ao and
- * enqueued into the queue QUEUE_SHADOW_RAY_CAST_AO_RAYS
+ * This kernels determines the rays for which a shadow_blocked() function
+ * associated with AO should be executed. Those rays for which a
+ * shadow_blocked() function for AO must be executed are marked with flag
+ * RAY_SHADOW_RAY_CAST_ao and enqueued into the queue
+ * QUEUE_SHADOW_RAY_CAST_AO_RAYS
  *
  * Ray state of rays that are terminated in this kernel are changed to RAY_UPDATE_BUFFER
  *
- * The input and output are as follows,
+ * Note on Queues:
+ * This kernel fetches rays from the queue QUEUE_ACTIVE_AND_REGENERATED_RAYS
+ * and processes only the rays of state RAY_ACTIVE.
+ * There are different points in this kernel where a ray may terminate and
+ * reach RAY_UPDATE_BUFFER state. These rays are enqueued into
+ * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue. These rays will still be present
+ * in QUEUE_ACTIVE_AND_REGENERATED_RAYS queue, but since their ray-state has
+ * been changed to RAY_UPDATE_BUFFER, there is no problem.
  *
- * rng_coop ---------------------------------------------|--- kernel_holdout_emission_blurring_pathtermination_ao ---|--- Queue_index (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * throughput_coop --------------------------------------|                                                           |--- PathState_coop
- * PathRadiance_coop ------------------------------------|                                                           |--- throughput_coop
- * Intersection_coop ------------------------------------|                                                           |--- L_transparent_coop
- * PathState_coop ---------------------------------------|                                                           |--- per_sample_output_buffers
- * L_transparent_coop -----------------------------------|                                                           |--- PathRadiance_coop
- * sd ---------------------------------------------------|                                                           |--- ShaderData
- * ray_state --------------------------------------------|                                                           |--- ray_state
- * Queue_data (QUEUE_ACTIVE_AND_REGENERATED_RAYS) -------|                                                           |--- Queue_data (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * Queue_index (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS) ---|                                                           |--- AOAlpha_coop
- * kg (globals) -----------------------------------------|                                                           |--- AOBSDF_coop
- * parallel_samples -------------------------------------|                                                           |--- AOLightRay_coop
- * per_sample_output_buffers ----------------------------|                                                           |
- * sw ---------------------------------------------------|                                                           |
- * sh ---------------------------------------------------|                                                           |
- * sx ---------------------------------------------------|                                                           |
- * sy ---------------------------------------------------|                                                           |
- * stride -----------------------------------------------|                                                           |
- * work_array -------------------------------------------|                                                           |
- * queuesize --------------------------------------------|                                                           |
- * start_sample -----------------------------------------|                                                           |
- *
- * Note on Queues :
- * This kernel fetches rays from the queue QUEUE_ACTIVE_AND_REGENERATED_RAYS and processes only
- * the rays of state RAY_ACTIVE.
- * There are different points in this kernel where a ray may terminate and reach RAY_UPDATE_BUFFER
- * state. These rays are enqueued into QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue. These rays will
- * still be present in QUEUE_ACTIVE_AND_REGENERATED_RAYS queue, but since their ray-state has been
- * changed to RAY_UPDATE_BUFFER, there is no problem.
- *
- * State of queues when this kernel is called :
+ * State of queues when this kernel is called:
  * At entry,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE and RAY_REGENERATED rays
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE rays.
- * QUEUE_SHADOW_RAY_CAST_AO_RAYS will be empty.
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE and
+ *     RAY_REGENERATED rays
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with
+ *     RAY_TO_REGENERATE rays.
+ *   - QUEUE_SHADOW_RAY_CAST_AO_RAYS will be empty.
  * At exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE, RAY_REGENERATED and RAY_UPDATE_BUFFER rays
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE and RAY_UPDATE_BUFFER rays
- * QUEUE_SHADOW_RAY_CAST_AO_RAYS will be filled with rays marked with flag RAY_SHADOW_RAY_CAST_AO
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE,
+ *     RAY_REGENERATED and RAY_UPDATE_BUFFER rays.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with
+ *     RAY_TO_REGENERATE and RAY_UPDATE_BUFFER rays.
+ *   - QUEUE_SHADOW_RAY_CAST_AO_RAYS will be filled with rays marked with
+ *     flag RAY_SHADOW_RAY_CAST_AO
  */
 ccl_device void kernel_holdout_emission_blurring_pathtermination_ao(KernelGlobals *kg)
 {
@@ -288,4 +270,3 @@ ccl_device void kernel_holdout_emission_blurring_pathtermination_ao(KernelGlobal
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_lamp_emission.h b/intern/cycles/kernel/split/kernel_lamp_emission.h
index 84de231b78c..f61643cceef 100644
--- a/intern/cycles/kernel/split/kernel_lamp_emission.h
+++ b/intern/cycles/kernel/split/kernel_lamp_emission.h
@@ -16,25 +16,9 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_lamp_emission
- * This is the 3rd kernel in the ray-tracing logic. This is the second of the
- * path-iteration kernels. This kernel takes care of the indirect lamp emission logic.
- * This kernel operates on QUEUE_ACTIVE_AND_REGENERATED_RAYS. It processes rays of state RAY_ACTIVE
- * and RAY_HIT_BACKGROUND.
+/* This kernel operates on QUEUE_ACTIVE_AND_REGENERATED_RAYS.
+ * It processes rays of state RAY_ACTIVE and RAY_HIT_BACKGROUND.
  * We will empty QUEUE_ACTIVE_AND_REGENERATED_RAYS queue in this kernel.
- * The input/output of the kernel is as follows,
- * Throughput_coop ------------------------------------|--- kernel_lamp_emission --|--- PathRadiance_coop
- * Ray_coop -------------------------------------------|                           |--- Queue_data(QUEUE_ACTIVE_AND_REGENERATED_RAYS)
- * PathState_coop -------------------------------------|                           |--- Queue_index(QUEUE_ACTIVE_AND_REGENERATED_RAYS)
- * kg (globals) ---------------------------------------|                           |
- * Intersection_coop ----------------------------------|                           |
- * ray_state ------------------------------------------|                           |
- * Queue_data (QUEUE_ACTIVE_AND_REGENERATED_RAYS) -----|                           |
- * Queue_index (QUEUE_ACTIVE_AND_REGENERATED_RAYS) ----|                           |
- * queuesize ------------------------------------------|                           |
- * use_queues_flag ------------------------------------|                           |
- * sw -------------------------------------------------|                           |
- * sh -------------------------------------------------|                           |
  */
 ccl_device void kernel_lamp_emission(KernelGlobals *kg)
 {
diff --git a/intern/cycles/kernel/split/kernel_next_iteration_setup.h b/intern/cycles/kernel/split/kernel_next_iteration_setup.h
index a6f26278116..ad1f6c78e8f 100644
--- a/intern/cycles/kernel/split/kernel_next_iteration_setup.h
+++ b/intern/cycles/kernel/split/kernel_next_iteration_setup.h
@@ -16,48 +16,33 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_setup_next_iteration kernel.
- * This is the tenth kernel in the ray tracing logic. This is the ninth
- * of the path iteration kernels. This kernel takes care of setting up
- * Ray for the next iteration of path-iteration and accumulating radiance
- * corresponding to AO and direct-lighting
+/*This kernel takes care of setting up ray for the next iteration of
+ * path-iteration and accumulating radiance corresponding to AO and
+ * direct-lighting
  *
- * Ray state of rays that are terminated in this kernel are changed to RAY_UPDATE_BUFFER
+ * Ray state of rays that are terminated in this kernel are changed
+ * to RAY_UPDATE_BUFFER.
  *
- * The input and output are as follows,
+ * Note on queues:
+ * This kernel fetches rays from the queue QUEUE_ACTIVE_AND_REGENERATED_RAYS
+ * and processes only the rays of state RAY_ACTIVE.
+ * There are different points in this kernel where a ray may terminate and
+ * reach RAY_UPDATE_BUFF state. These rays are enqueued into
+ * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue. These rays will still be present
+ * in QUEUE_ACTIVE_AND_REGENERATED_RAYS queue, but since their ray-state has
+ * been changed to RAY_UPDATE_BUFF, there is no problem.
  *
- * rng_coop ---------------------------------------------|--- kernel_next_iteration_setup -|--- Queue_index (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * throughput_coop --------------------------------------|                                 |--- Queue_data (QUEUE_HITBF_BUFF_UPDATE_TOREGEN_RAYS)
- * PathRadiance_coop ------------------------------------|                                 |--- throughput_coop
- * PathState_coop ---------------------------------------|                                 |--- PathRadiance_coop
- * sd ---------------------------------------------------|                                 |--- PathState_coop
- * ray_state --------------------------------------------|                                 |--- ray_state
- * Queue_data (QUEUE_ACTIVE_AND_REGENERATD_RAYS) --------|                                 |--- Ray_coop
- * Queue_index (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS) ---|                                 |--- use_queues_flag
- * Ray_coop ---------------------------------------------|                                 |
- * kg (globals) -----------------------------------------|                                 |
- * LightRay_dl_coop -------------------------------------|
- * ISLamp_coop ------------------------------------------|
- * BSDFEval_coop ----------------------------------------|
- * LightRay_ao_coop -------------------------------------|
- * AOBSDF_coop ------------------------------------------|
- * AOAlpha_coop -----------------------------------------|
- *
- * Note on queues,
- * This kernel fetches rays from the queue QUEUE_ACTIVE_AND_REGENERATED_RAYS and processes only
- * the rays of state RAY_ACTIVE.
- * There are different points in this kernel where a ray may terminate and reach RAY_UPDATE_BUFF
- * state. These rays are enqueued into QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue. These rays will
- * still be present in QUEUE_ACTIVE_AND_REGENERATED_RAYS queue, but since their ray-state has been
- * changed to RAY_UPDATE_BUFF, there is no problem.
- *
- * State of queues when this kernel is called :
+ * State of queues when this kernel is called:
  * At entry,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE, RAY_REGENERATED, RAY_UPDATE_BUFFER rays.
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE and RAY_UPDATE_BUFFER rays
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE,
+ *     RAY_REGENERATED, RAY_UPDATE_BUFFER rays.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with
+ *     RAY_TO_REGENERATE and RAY_UPDATE_BUFFER rays.
  * At exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE, RAY_REGENERATED and more RAY_UPDATE_BUFFER rays.
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE and more RAY_UPDATE_BUFFER rays
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE,
+ *     RAY_REGENERATED and more RAY_UPDATE_BUFFER rays.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with
+ *     RAY_TO_REGENERATE and more RAY_UPDATE_BUFFER rays.
  */
 ccl_device void kernel_next_iteration_setup(KernelGlobals *kg)
 {
@@ -182,4 +167,3 @@ ccl_device void kernel_next_iteration_setup(KernelGlobals *kg)
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_path_init.h b/intern/cycles/kernel/split/kernel_path_init.h
index f44aff30fa9..f879fca5009 100644
--- a/intern/cycles/kernel/split/kernel_path_init.h
+++ b/intern/cycles/kernel/split/kernel_path_init.h
@@ -21,7 +21,6 @@ CCL_NAMESPACE_BEGIN
  *
  * Ray state of rays outside the tile-boundary will be marked RAY_INACTIVE
  */
-
 ccl_device void kernel_path_init(KernelGlobals *kg) {
 	int ray_index = ccl_global_id(0) + ccl_global_id(1) * ccl_global_size(0);
 
@@ -101,4 +100,3 @@ ccl_device void kernel_path_init(KernelGlobals *kg) {
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_queue_enqueue.h b/intern/cycles/kernel/split/kernel_queue_enqueue.h
index 70ec92b394b..f4a4657d23f 100644
--- a/intern/cycles/kernel/split/kernel_queue_enqueue.h
+++ b/intern/cycles/kernel/split/kernel_queue_enqueue.h
@@ -16,36 +16,24 @@
 
 CCL_NAMESPACE_BEGIN
 
-/*
- * The kernel "kernel_queue_enqueue" enqueues rays of
- * different ray state into their appropriate Queues;
- * 1. Rays that have been determined to hit the background from the
- * "kernel_scene_intersect" kernel
- * are enqueued in QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS;
- * 2. Rays that have been determined to be actively participating in path-iteration will be enqueued into QUEUE_ACTIVE_AND_REGENERATED_RAYS.
- *
- * The input and output of the kernel is as follows,
- *
- * ray_state -------------------------------------------|--- kernel_queue_enqueue --|--- Queue_data (QUEUE_ACTIVE_AND_REGENERATED_RAYS & QUEUE_HITBF_BUFF_UPDATE_TOREGEN_RAYS)
- * Queue_index(QUEUE_ACTIVE_AND_REGENERATED_RAYS) ------|                           |--- Queue_index (QUEUE_ACTIVE_AND_REGENERATED_RAYS & QUEUE_HITBF_BUFF_UPDATE_TOREGEN_RAYS)
- * Queue_index(QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS) ---|                           |
- * queuesize -------------------------------------------|                           |
+/* This kernel enqueues rays of different ray state into their
+ * appropriate queues:
  *
- * Note on Queues :
- * State of queues during the first time this kernel is called :
- * At entry,
- * Both QUEUE_ACTIVE_AND_REGENERATED_RAYS and QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be empty.
- * At exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE rays
- * QUEUE_HITBF_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_HIT_BACKGROUND rays.
+ * 1. Rays that have been determined to hit the background from the
+ *    "kernel_scene_intersect" kernel are enqueued in
+ *    QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS;
+ * 2. Rays that have been determined to be actively participating in pat
+ *    -iteration will be enqueued into QUEUE_ACTIVE_AND_REGENERATED_RAYS.
  *
- * State of queue during other times this kernel is called :
+ * State of queue during other times this kernel is called:
  * At entry,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be empty.
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will contain RAY_TO_REGENERATE and RAY_UPDATE_BUFFER rays.
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be empty.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will contain RAY_TO_REGENERATE
+ *     and RAY_UPDATE_BUFFER rays.
  * At exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE rays.
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE, RAY_UPDATE_BUFFER, RAY_HIT_BACKGROUND rays.
+ *   - QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE rays.
+ *   - QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with
+ *     RAY_TO_REGENERATE, RAY_UPDATE_BUFFER, RAY_HIT_BACKGROUND rays.
  */
 ccl_device void kernel_queue_enqueue(KernelGlobals *kg)
 {
@@ -101,4 +89,3 @@ ccl_device void kernel_queue_enqueue(KernelGlobals *kg)
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_scene_intersect.h b/intern/cycles/kernel/split/kernel_scene_intersect.h
index f6fc370060e..33d0df7a2cb 100644
--- a/intern/cycles/kernel/split/kernel_scene_intersect.h
+++ b/intern/cycles/kernel/split/kernel_scene_intersect.h
@@ -16,51 +16,13 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_scene_intersect kernel.
- * This is the second kernel in the ray tracing logic. This is the first
- * of the path iteration kernels. This kernel takes care of scene_intersect function.
+/* This kernel takes care of scene_intersect function.
  *
  * This kernel changes the ray_state of RAY_REGENERATED rays to RAY_ACTIVE.
  * This kernel processes rays of ray state RAY_ACTIVE
- * This kernel determines the rays that have hit the background and changes their ray state to RAY_HIT_BACKGROUND.
- *
- * The input and output are as follows,
- *
- * Ray_coop ---------------------------------------|--------- kernel_scene_intersect----------|--- PathState
- * PathState_coop ---------------------------------|                                          |--- Intersection
- * ray_state --------------------------------------|                                          |--- ray_state
- * use_queues_flag --------------------------------|                                          |
- * QueueData(QUEUE_ACTIVE_AND_REGENERATED_RAYS) ---|                                          |
- * kg (globals) -----------------------------------|                                          |
- * rng_coop ---------------------------------------|                                          |
- * sw ---------------------------------------------|                                          |
- * sh ---------------------------------------------|                                          |
- * queuesize --------------------------------------|                                          |
- *
- * Note on Queues :
- * Ideally we would want kernel_scene_intersect to work on queues.
- * But during the very first time, the queues will be empty and hence we perform a direct mapping
- * between ray-index and thread-index; From the next time onward, the queue will be filled and
- * we may start operating on queues.
- *
- * State of queue during the first time this kernel is called :
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS and QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be empty.before and after this kernel
- *
- * State of queues during other times this kernel is called :
- * At entry,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will have a mix of RAY_ACTIVE, RAY_UPDATE_BUFFER and RAY_REGENERATED rays;
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE and RAY_UPDATE_BUFFER rays ;
- * (The rays that are in the state RAY_UPDATE_BUFFER in both the queues are actually the same rays; These
- * are the rays that were in RAY_ACTIVE state during the initial enqueue but on further processing
- * , by different kernels, have turned into RAY_UPDATE_BUFFER rays. Since all kernel, even after fetching from
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS, proceed further based on ray state information, RAY_UPDATE_BUFFER rays
- * being present in QUEUE_ACTIVE_AND_REGENERATED_RAYS does not cause any logical issues)
- * At exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS - All RAY_REGENERATED rays will have been converted to RAY_ACTIVE and
- * Some rays in QUEUE_ACTIVE_AND_REGENERATED_RAYS queue will move to state RAY_HIT_BACKGROUND
- * QUEUE_HITBF_BUFF_UPDATE_TOREGEN_RAYS - no change
+ * This kernel determines the rays that have hit the background and changes
+ * their ray state to RAY_HIT_BACKGROUND.
  */
-
 ccl_device void kernel_scene_intersect(KernelGlobals *kg)
 {
 	/* Fetch use_queues_flag */
@@ -146,4 +108,3 @@ ccl_device void kernel_scene_intersect(KernelGlobals *kg)
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_shader_eval.h b/intern/cycles/kernel/split/kernel_shader_eval.h
index 4bd5c8b6eb0..43872c6f388 100644
--- a/intern/cycles/kernel/split/kernel_shader_eval.h
+++ b/intern/cycles/kernel/split/kernel_shader_eval.h
@@ -16,35 +16,12 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_shader_eval kernel
- * This kernel is the 5th kernel in the ray tracing logic. This is
- * the 4rd kernel in path iteration. This kernel sets up the ShaderData
- * structure from the values computed by the previous kernels. It also identifies
- * the rays of state RAY_TO_REGENERATE and enqueues them in QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue.
+/* This kernel sets up the ShaderData structure from the values computed
+ * by the previous kernels.
  *
- * The input and output of the kernel is as follows,
- * rng_coop -------------------------------------------|--- kernel_shader_eval --|--- sd
- * Ray_coop -------------------------------------------|                         |--- Queue_data (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * PathState_coop -------------------------------------|                         |--- Queue_index (QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)
- * Intersection_coop ----------------------------------|                         |
- * Queue_data (QUEUE_ACTIVE_AND_REGENERATD_RAYS)-------|                         |
- * Queue_index(QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS)---|                         |
- * ray_state ------------------------------------------|                         |
- * kg (globals) ---------------------------------------|                         |
- * queuesize ------------------------------------------|                         |
- *
- * Note on Queues :
- * This kernel reads from the QUEUE_ACTIVE_AND_REGENERATED_RAYS queue and processes
- * only the rays of state RAY_ACTIVE;
- * State of queues when this kernel is called,
- * at entry,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE and RAY_REGENERATED rays
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be empty.
- * at exit,
- * QUEUE_ACTIVE_AND_REGENERATED_RAYS will be filled with RAY_ACTIVE and RAY_REGENERATED rays
- * QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be filled with RAY_TO_REGENERATE rays
+ * It also identifies the rays of state RAY_TO_REGENERATE and enqueues them
+ * in QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue.
  */
-
 ccl_device void kernel_shader_eval(KernelGlobals *kg)
 {
 	/* Enqeueue RAY_TO_REGENERATE rays into QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS queue. */
@@ -91,4 +68,3 @@ ccl_device void kernel_shader_eval(KernelGlobals *kg)
 }
 
 CCL_NAMESPACE_END
-
diff --git a/intern/cycles/kernel/split/kernel_shadow_blocked_ao.h b/intern/cycles/kernel/split/kernel_shadow_blocked_ao.h
index e153c16bd68..a1eb0d1eccd 100644
--- a/intern/cycles/kernel/split/kernel_shadow_blocked_ao.h
+++ b/intern/cycles/kernel/split/kernel_shadow_blocked_ao.h
@@ -16,33 +16,7 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_shadow_blocked kernel.
- * This is the ninth kernel in the ray tracing logic. This is the eighth
- * of the path iteration kernels. This kernel takes care of "shadow ray cast"
- * logic of the direct lighting and AO  part of ray tracing.
- *
- * The input and output are as follows,
- *
- * PathState_coop ----------------------------------|--- kernel_shadow_blocked --|
- * LightRay_dl_coop --------------------------------|                            |--- LightRay_dl_coop
- * LightRay_ao_coop --------------------------------|                            |--- LightRay_ao_coop
- * ray_state ---------------------------------------|                            |--- ray_state
- * Queue_data(QUEUE_SHADOW_RAY_CAST_AO_RAYS &       |                            |--- Queue_data (QUEUE_SHADOW_RAY_CAST_AO_RAYS & QUEUE_SHADOW_RAY_CAST_AO_RAYS)
-              QUEUE_SHADOW_RAY_CAST_DL_RAYS) -------|                            |
- * Queue_index(QUEUE_SHADOW_RAY_CAST_AO_RAYS&
-              QUEUE_SHADOW_RAY_CAST_DL_RAYS) -------|                            |
- * kg (globals) ------------------------------------|                            |
- * queuesize ---------------------------------------|                            |
- *
- * Note on sd_shadow : sd_shadow is neither input nor output to this kernel. sd_shadow is filled and consumed in this kernel itself.
- * Note on queues :
- * The kernel fetches from QUEUE_SHADOW_RAY_CAST_AO_RAYS queue. We will empty this queues in this kernel.
- * State of queues when this kernel is called :
- * state of queues QUEUE_ACTIVE_AND_REGENERATED_RAYS and QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be same
- * before and after this kernel call.
- * QUEUE_SHADOW_RAY_CAST_AO_RAYS will be filled with rays marked with flags RAY_SHADOW_RAY_CAST_AO during kernel entry.
- * QUEUE_SHADOW_RAY_CAST_AO_RAYS will be empty at kernel exit.
- */
+/* Shadow ray cast for AO. */
 ccl_device void kernel_shadow_blocked_ao(KernelGlobals *kg)
 {
 	int lidx = ccl_local_id(1) * ccl_local_id(0) + ccl_local_id(0);
diff --git a/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h b/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h
index cfd8d78c2de..2e5629944dc 100644
--- a/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h
+++ b/intern/cycles/kernel/split/kernel_shadow_blocked_dl.h
@@ -16,33 +16,7 @@
 
 CCL_NAMESPACE_BEGIN
 
-/* Note on kernel_shadow_blocked kernel.
- * This is the ninth kernel in the ray tracing logic. This is the eighth
- * of the path iteration kernels. This kernel takes care of "shadow ray cast"
- * logic of the direct lighting and AO  part of ray tracing.
- *
- * The input and output are as follows,
- *
- * PathState_coop ----------------------------------|--- kernel_shadow_blocked --|
- * LightRay_dl_coop --------------------------------|                            |--- LightRay_dl_coop
- * LightRay_ao_coop --------------------------------|                            |--- LightRay_ao_coop
- * ray_state ---------------------------------------|                            |--- ray_state
- * Queue_data(QUEUE_SHADOW_RAY_CAST_AO_RAYS &       |                            |--- Queue_data (QUEUE_SHADOW_RAY_CAST_AO_RAYS & QUEUE_SHADOW_RAY_CAST_AO_RAYS)
-              QUEUE_SHADOW_RAY_CAST_DL_RAYS) -------|                            |
- * Queue_index(QUEUE_SHADOW_RAY_CAST_AO_RAYS&
-              QUEUE_SHADOW_RAY_CAST_DL_RAYS) -------|                            |
- * kg (globals) ------------------------------------|                            |
- * queuesize ---------------------------------------|                            |
- *
- * Note on sd_shadow : sd_shadow is neither input nor output to this kernel. sd_shadow is filled and consumed in this kernel itself.
- * Note on queues :
- * The kernel fetches from QUEUE_SHADOW_RAY_CAST_DL_RAYS queue. We will empty this queue in this kernel.
- * State of queues when this kernel is called :
- * state of queues QUEUE_ACTIVE_AND_REGENERATED_RAYS and QUEUE_HITBG_BUFF_UPDATE_TOREGEN_RAYS will be same
- * before and after this kernel call.
- * QUEUE_SHADOW_RAY_CAST_DL_RAYS will be filled with rays marked with flags RAY_SHADOW_RAY_CAST_DL, during kernel entry.
- * QUEUE_SHADOW_RAY_CAST_DL_RAYS will be empty at kernel exit.
- */
+/* Shadow ray cast for direct visible light. */
 ccl_device void kernel_shadow_blocked_dl(KernelGlobals *kg)
 {
 	int lidx = ccl_local_id(1) * ccl_local_id(0) + ccl_local_id(0);
@@ -88,4 +62,3 @@ ccl_device void kernel_shadow_blocked_dl(KernelGlobals *kg)
 }
 
 CCL_NAMESPACE_END
-