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When the timeline is locked then you will not observe any progress in time, and the simulation is “pinned” to the current frame. This means that the simulation is running, but frames are not incremented – the simulation is performed at a single frame, e.g. 0 or 50. As a side effect, animation data will not be evaluated. In order to unlock the timeline, stop the simulation with a click on “Simulate”, and click on the button again.
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In order to change the simulation's start please enter a (positive) frame number here. The start frame will be displayed in the “Timeline Bar” timeline bar as a black number. During playback, this field defines the point in time when playback will start.
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1. Go to first frame | 2. Go one frame back | 3.Play backward | 4. Current frame | 5. Play forward | 6. Go one frame ahead | 7.Go to last frame | 8. Loop | 9. → Create OpenGL preview