"Reverse time in the middle of topology change"

Revert "Merge remote-tracking branch 'origin/thesis/2022/fieldline-rendering' into thesis/2022/fieldline-rendering"

This reverts commit fbf48c23.

Merge remote-tracking branch 'origin/thesis/2022/fieldline-rendering' into thesis/2022/fieldline-rendering

Merge for "change time direction during topology change" and "Improved vertex buffer implementation"

Small fixes to get the code in proper shape for the CCMC conference

Now, only one vertex buffer is used which contains a vertex struct with position, topology and alpha information. This solved the issues with fade for IMFs at start and end. Also changed the colors of fieldlines.

Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Added search function to find optimal fieldline split index. Uses a few magic numbers to get good time values.
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Bugfixes and robustness
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Dayside backwards works without crash, still some undefined behaviour.
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

No longer swapping key frame vertices, instead new positions are created through interpolation. Bugs left to solve.
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

No more change to original object at vertex swap
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Continous visualization fo dayside reconnection is possible. Still some bugs to be patched. Code to be refactored
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Starting position of traverser fixed so the traveling time of each matching pair of traversers from start to reconnection point would match. Modifies therefore the start point on the pathline without modifying the pathline.

Fieldline positions' are only updated if current time is within its lifetime. The birth of each fieldline is set when reading seed point, while the death is set to numerical max for now.

The float alpha value sent to the shader should be correct, but the fieldlines wont fade properly. Possibly because blending function

Fieldlines are now only visible between birth- and death time. They still start at simulation start time however.

Co-authored-by: Simon Brefält <simbr615@student.liu.se>

Birth times for seed points are now saved in the fieldline state. 

Added functionality to take two pairs of input seed points. Trace path lines from each seed point and then concatenate the path lines created for each pair.

Matching fieldlines now render properly 
Co-authored-by: Simon Brefält <simbr615@student.liu.se>

Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Added functionality to render matching fieldlines in the initialize() in renderablemovingfieldlines.cpp. Work needs to be done for a good visualization.
Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Co-authored-by: Måns Aronsson <m.k.j.aronsson@gmail.com>

Added functionality for moving a seedpoint in the eigenvector direction, commented some previously uncommented code