Version: 2017.3

TextureImporterSettings.mipMapsPreserveCoverage

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public bool mipMapsPreserveCoverage ;

Description

Enables or disables coverage-preserving alpha MIP mapping.

Enable this to rescale the alpha values of computed MIP maps so coverage is preserved. This means a higher percentage of pixels passes the alpha test and lower MIP map levels do not become more transparent. This is disabled by default (set to false).