Playback slow with large static Text Object
Closed, ResolvedPublic


System Information
Windows7 x64, GTX 1070

Blender Version

When adding a Text object with 100+ words, the animation playback speed goes down to <10fps
It the only value it seems to be related is the 'Preview U' Resolution.

Looks like the Dependency Graph rebuilds the whole Text-Mesh on every frame, even if there is nothing animated.

ronan ducluzeau (zeauro) triaged this task as Confirmed priority.EditedTue, Nov 28, 4:36 PM

Confirmed on ubuntu with master 7c64e33 and official 2.79

In attached .blend file, I used Lyapunov Texture Template to create a long 3D text object.
At default Preview resolution of 12, it corresponds to 254 193 tris interpolated. At Preview U resolution set at 1, it correspond to 33 973 tris. Of course playback is a little bit better but not great.

And it becomes really unacceptable when draw type is set to Bounds to reduce display of text to a wire of 4 lines : there is no improvement of fps.

Edit; Oops. It looks like problem does not exist when blender is launched with new depsgraph.
By typing in commandline blender --enable-new-depsgraph, there is no more problem.
Is it something that should be supported by legacy depsgraph in 2.79a ?

Damjan (Atair) added a comment.EditedWed, Nov 29, 1:39 AM

With the new depsgraph the playback lag is gone, but a new problem is introduced:
Transforming (Moving) The Textobject is now very slow / choppy.
Easily noticeable with 250+ Words
Should this go into a separate task?