# 2019.07.09 Hangout

**URL:** <https://discourse.slicer.org/t/2019-07-09-hangout/7484>\
**Category:** Weekly meetings\
**Created:** [July 9, 2019, 1:35pm UTC](https://discourse.slicer.org/t/2019-07-09-hangout/7484 "2019-07-09T13:35:42Z")\
**Posts on this page:** 1\
**Showing post:** 3

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**Author:** ![Sam\_Horvath](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/sam_horvath/32/3092_2.png) [@Sam\_Horvath](https://discourse.slicer.org/u/Sam_Horvath)\
**Post date:** [July 9, 2019, 3:01pm UTC](https://discourse.slicer.org/t/2019-07-09-hangout/7484/3 "2019-07-09T15:01:35Z")

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## Minutes

### Main topic: Keyframe animation

- See [this discussion](https://discourse.slicer.org/t/support-for-keyframe-based-animation/6885) and [this question](https://discourse.slicer.org/t/is-there-interest-in-higher-quality-rendering-for-slicer/6862)
- Discussed keyframe animation approaches and progress
  - Use of dummy master node in Sequence to control interpolation / timestep
  - Keyframe is the actual, non interpolated data
  - Pre-calculating interpolated data vs interpolate at creation of animation
    - Data / memory usage is relevant here

  - Repeating sub-sequences? (ex. model rocking)

- Role of Sequences / Sequence Browser / Dependency minimization
  - We want to avoid hard dependencies on new interpolation nodes / methods
  - Node Sequencer is part of Sequences
  - Interpolation is the role of the Browser?
  - How does the screen capture module play into this?

- Key frame editing!
  - Edit camera paths / focus using new markups - oriented b-spline
  - Transforms and transfer functions already have editors

- Reconciling requested FPS with data sources
- Invented term virtual node (data generated at runtime)
- Moving sequences into the core due to the increasing usage (as remote module to start)

### Volume rendering: Thoughts

- Discussion of [Drishti Software](https://github.com/nci/drishti)
- Rendering improvements in VTK: [physics based rendering](https://gitlab.kitware.com/vtk/vtk/merge_requests/5584)

### Large Volume Support: Pending issues

- Need more support than just visualization
- Approach should address segmentation and other interactions
- Better management of OpenGL/GPU errors and info
- Texture memory management
  - Figuring out how much GPU memory is available is hard
  - Would be a super useful tool in VTK

- level of detail in hierarchical volumes
- mipmapping for volume rendering??

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_[View the full topic](https://discourse.slicer.org/t/2019-07-09-hangout/7484)._