Cycles: Fix triangle ribbons hair in viewport and ortho camera

There were several issues involved into triangle ribbons hair:

- Even for the viewport rendering the blender scene camera was
  used for orientation. This made hair triangles oriented to
  the scene camera, not to the viewport camera.

- Triangle orientation was actually supposing the camera is
  perspective. Triangles weren't oriented properly for the
  orthographic camera resulting in different hair width across
  it's length.

This issues are solved now, but there are some related TODOs:

- Rotating viewport doesn't re-orient the triangles, so after
  viewport navigation hair might not look correct. However,
  with this fix toggling viewport render (to force hair sync)
  makes viewport render correct.

  This isn't so much trivial fix, would require making BVH
  aware of the dynamic triangle orientation, so they get
  properly oriented without full hair re-sync.

- Panorama camera behavior didn't change but looks like it
  should, however not really sure atm what's the right thing
  to do here.

1 files changed, 1 insertions, 1 deletions

diff --git a/intern/cycles/blender/blender_session.cpp b/intern/cycles/blender/blender_session.cpp
index 3e84110c335..4ff3d89f9f1 100644
--- a/intern/cycles/blender/blender_session.cpp
+++ b/intern/cycles/blender/blender_session.cpp
@@ -116,8 +116,8 @@ void BlenderSession::create_session()
 	if(b_v3d) {
 		if(session_pause == false) {
 			/* full data sync */
-			sync->sync_data(b_v3d, b_engine.camera_override(), &python_thread_state);
 			sync->sync_view(b_v3d, b_rv3d, width, height);
+			sync->sync_data(b_v3d, b_engine.camera_override(), &python_thread_state);
 		}
 	}
 	else {