I have the next code:
I am trying to make a mask (only one shape that I would like to use as an analysis region) with: all elevations less than 4.100 meters (from DEM), all area with water (NDWI) and all slopes less than 15 degrees (from DEM).
I could mask it but I don't know how to join the three layers and I dont know either how to convert the 255 value to NoData.
How can I do it to insert all this variables in one layer and then use that layer as a region?
var region= MNDWI_DPS
//NDWI
var NDWI = ee.Image('MODIS/MCD43A4_NDWI/MCD43A4_005_2016_05_16')
var visualize = NDWI.visualize({bands: ['NDWI'], min: -1, max: 0}).clip(region);
//DEM+SLOPE
var MDE = ee.Image('USGS/SRTMGL1_003')
var terrain = ee.Algorithms.Terrain(ee.Image('USGS/SRTMGL1_003'));
var visualize1 = MDE.visualize({bands: ['elevation'], min: 0, max: 4100}).clip(region);
var slope = ee.Terrain.slope(MDE);
var visualize2 = slope.visualize({bands: ['slope'], min: 0, max: 15}).clip(region)
Map.addLayer(visualize.clip(region))
Map.addLayer(visualize1.clip(region))
Map.addLayer(visualize2.clip(region))