Most of the "Playback" menu's entries are self-explaining. Therefore, only some important commands are explained.
OpenGL Preview
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Create a preview from the current viewport perspective to evaluate your simulation in realtime. More information and workflows → here.
Maxwell Preview
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Create a rendered preview from the current viewport perspective. More information and workflows → here.
Render
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Create a high-quality Maxwell render (still or animation). More information and workflows → here.
Video Preview Cached Frames
Cached frames are indicated as an orange bar in the timeline. Only those frames will be used for the preview.
Send Preview to Job Manager
With an appropriate number of licenses it is is possible to distribute the Maxwell preview creation over a network.