Cycles: Refactor Progress system to provide better estimates

The Progress system in Cycles had two limitations so far:
 - It just counted tiles, but ignored their size. For example, when rendering a 600x500 image with 512x512 tiles, the right 88x500 tile would count for 50% of the progress, although it only covers 15% of the image.
 - Scene update time was incorrectly counted as rendering time - therefore, the remaining time started very long and gradually decreased.

This patch fixes both problems:
First of all, the Progress now has a function to ignore time spans, and that is used to ignore scene update time.
The larger change is the tile size: Instead of counting samples per tile, so that the final value is num_samples*num_tiles, the code now counts every sample for every pixel, so that the final value is num_samples*num_pixels.

Along with that, some unused variables were removed from the Progress and Session classes.

Reviewers: brecht, sergey, #cycles

Subscribers: brecht, candreacchio, sergey

Differential Revision: https://developer.blender.org/D2214

1 files changed, 2 insertions, 2 deletions

diff --git a/intern/cycles/device/device_task.h b/intern/cycles/device/device_task.h
index 8423e83bdfd..8bd54c3d2b0 100644
--- a/intern/cycles/device/device_task.h
+++ b/intern/cycles/device/device_task.h
@@ -56,10 +56,10 @@ public:
 	int get_subtask_count(int num, int max_size = 0);
 	void split(list<DeviceTask>& tasks, int num, int max_size = 0);
 
-	void update_progress(RenderTile *rtile);
+	void update_progress(RenderTile *rtile, int pixel_samples = -1);
 
 	function<bool(Device *device, RenderTile&)> acquire_tile;
-	function<void(void)> update_progress_sample;
+	function<void(long, int)> update_progress_sample;
 	function<void(RenderTile&)> update_tile_sample;
 	function<void(RenderTile&)> release_tile;
 	function<bool(void)> get_cancel;