Weekly Development Notes #35 – Override Frame Feature and Bug Fixes

Covering the week of October 5th – October 9th, 2020.

Hello! It’s our 35th development update for the FLIP Fluids liquid simulation addon for Blender! Just a small update as it was a short development week. I was away for a four day weekend during Canadian Thanksgiving.

I didn’t expect on having enough changes in the addon this week to warrant a new experimental release ready for this week, but I ended up finding some time to add a small, but well-needed and convenient _Override Frame_ feature to the addon.

Override Frame

This has been a common request. When importing an Alembic cache into Blender, the modifier has an Override Frame setting that allows the user to set or keyframe the current loaded frame of the Alembic cache (screenshot). This would be a useful setting to add to the FLIP Fluids Helper Menu.

We have had users ask how to create an animations like these:

  • Playback the simulation normally, then freeze frames while the camera rotates around the fluid, and then resume playback normally.
  • Playback the simulation in reverse.
  • Playback only every second or third frame for a claymation/stopmotion type effect.

At the moment, the workaround to render an animation like this is to export the simulation to Alembic and then keyframe the override frame setting. Another workaround is to render out multiple animation sequences and stich them together for the complete animation. These workarounds are both inconvenient.

Last week I had a chance to implement an Override Frame feature for the FLIP Fluids Helper Menu (Documentation) and this can be tested in today’s experimental release (v9.0.9.07):

Some settings in the Helper Menu have been re-arranged and there is now an option to select different playback modes

  • Timeline: The default, just loads the simulation according to the current timeline frame.
  • Override Frame: Set a custom frame value for which simulation frame is loaded. This value can be keyframed for complex control over animation playback, and is also compatible with Blender’s driver features.
    • There is also an operator to automatically set the interpolation mode in the graph editor to Linear
  • Hold Frame: Works the same as how the hold frame feature worked before: hold a single frame in place regardless of timeline position. Useful for when you only need to render a single frame.

Force Field Experimental Version 9.0.9.07

Want to try out new features and bug fixes? Theses changes have been added to our Force Field Experimental Builds Package in the latest version!

Release Notes v9.0.9.07

Release notes for other versions can be found here.

  • A minor update that mainly consists of an Override Frame feature similar to Blender’s Alembic Mesh Cache setting and some bug fixes.
  • Added Override Frame settings to FLIP Fluids Helper Menu that works similar to the setting of the same name in Blender’s Alembic Cache modifier.
    • TIP: Keyframing the override frame number can allow for complex control over simulation playback (ex: start/stop freeze frames, reverse animation)
    • The addition of this feature caused some settings to be re-arranged in the Helper Menu and some settings have moved into a separate Simulation Playback submenu (Documentation).
  • The FLIP Meshes to Collections operator in the Helper Menu now groups all of the whitewater meshes into a single WHITEWATER collection instead of separating them each into separate collections.
  • Bug Fix: Fixed error that could be triggered when using the FLIP Objects to Collections operator in the Helper Menu.
  • Bug Fix: Fixed potential crash issues that could be triggered when using Blender’s Undo (Ctrl+Z) after using the Create Domain operator in the Helper Menu.

Featured Artwork

I saw some beautiful animations over the last week that I wanted to share! Post on our Facebook Page, or tag us @FLIPFluids on Twitter or @flip.fluids on Instagram for a chance to be featured.

Re-imagining the App Store icon – created by Jonathan Nash

@offshootuk on Twitter | @offshoot.3d on Instagram

Viscous liquid over FIB-SEM mitochondria imaging data – created by Peter I.

@pitvandyck on Twitter

FLIPFluids waterfall – created by cgDroid

@cgdroid65 on Instagram | cgDroid on YouTube

Cute fluid test – created by arc4g

@arc4g on Instagram | @arc4g on Twitter | Join the discussion on Reddit

5 1 vote
Article Rating