(ORG-4987)
Origin 9.1 have has added Anti-aliasing support for 2D graphs. This allows nicer view of 2D graphs on the monitor.
The images below show screen capture of a 2D line plot with and without anti-aliasing (click to pop up larger image):
Turn Anti-Aliasing On
You can toggle Anti-Aliasing on and off using the button on Graphs toolbar for the active graph.
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Additional Anti-Aliasing Settings
(ORG-6500)
For the graphs that has Anti-Aliasing turned on, there are additional global settings to fine tune which type of drawing to use anti-aliasing. These can be found on Graph tab of Tools: Options dialog.