Bug: Rounding error in juce_VST3_Wrapper.cpp results in wrong preset names communicated with host

Audio Plugins
1

In juce_VST3_Wrapper.cpp, the following line has problems with rounding errors:

475:    toString128 (result, owner.getProgramName (static_cast<int> (value * info.stepCount)));

For certain values (e.g. info.stepCount == 31 and value = 0.1290322542…) this would result in incorrect values due to rounding errors (in this example: 3.9999 which is incorrectly truncated to 3 instead of being properly rounded to 4). This results in the wrong preset name appearing in a VST3 host.

A simple round() fixes this.

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2

Just to be a little clearer: The problem appears when the plugin changes its current preset and calls updateHostDisplay(). This results int he host displaying the wrong preset name due to the rounding error.

3

This is fixed in the latest version of JUCE.

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