Cycles: Implement denoising option for reducing noise in the rendered image

This commit contains the first part of the new Cycles denoising option,
which filters the resulting image using information gathered during rendering
to get rid of noise while preserving visual features as well as possible.

To use the option, enable it in the render layer options. The default settings
fit a wide range of scenes, but the user can tweak individual settings to
control the tradeoff between a noise-free image, image details, and calculation
time.

Note that the denoiser may still change in the future and that some features
are not implemented yet. The most important missing feature is animation
denoising, which uses information from multiple frames at once to produce a
flicker-free and smoother result. These features will be added in the future.

Finally, thanks to all the people who supported this project:

- Google (through the GSoC) and Theory Studios for sponsoring the development
- The authors of the papers I used for implementing the denoiser (more details
  on them will be included in the technical docs)
- The other Cycles devs for feedback on the code, especially Sergey for
  mentoring the GSoC project and Brecht for the code review!
- And of course the users who helped with testing, reported bugs and things
  that could and/or should work better!

1 files changed, 3 insertions, 3 deletions

diff --git a/intern/cycles/device/device_split_kernel.h b/intern/cycles/device/device_split_kernel.h
index 58c2fdbb077..68c2ba974a5 100644
--- a/intern/cycles/device/device_split_kernel.h
+++ b/intern/cycles/device/device_split_kernel.h
@@ -80,16 +80,16 @@ private:
 	 */
 	device_memory split_data;
 	device_vector<uchar> ray_state;
-	device_memory queue_index; /* Array of size num_queues * sizeof(int) that tracks the size of each queue. */
+	device_only_memory<int> queue_index; /* Array of size num_queues that tracks the size of each queue. */
 
 	/* Flag to make sceneintersect and lampemission kernel use queues. */
-	device_memory use_queues_flag;
+	device_only_memory<char> use_queues_flag;
 
 	/* Approximate time it takes to complete one sample */
 	double avg_time_per_sample;
 
 	/* Work pool with respect to each work group. */
-	device_memory work_pool_wgs;
+	device_only_memory<unsigned int> work_pool_wgs;
 
 	/* clos_max value for which the kernels have been loaded currently. */
 	int current_max_closure;