Grid Proximity Buffer
grid_tools
QgsProcessingParameterRasterLayer|SOURCE|Source Grid|None|False
QgsProcessingParameterNumber|DIST|Buffer distance|QgsProcessingParameterNumber.Double|500.0|False|None|None
QgsProcessingParameterNumber|IVAL|Equidistance|QgsProcessingParameterNumber.Double|100.0|False|None|None
QgsProcessingParameterRasterDestination|DISTANCE|Distance Grid
QgsProcessingParameterRasterDestination|ALLOC|Allocation Grid
QgsProcessingParameterRasterDestination|BUFFER|Buffer Grid