Left - a noise texture without a color ramp
Right - same noise texture with a color ramp
Quote from the Blender docs: "The ColorRamp Node is used for mapping values to colors with the use of a gradient. It works exactly the same way as a Colorband for textures and materials, using the Factor value as a slider or index to the color ramp shown, and outputting a color value and an alpha value from the output sockets. "
Cu, Manu.
EDIT:
So I made something with the “if” node, but the result isn’t exactly the same, as it misses the gradient between 0 and 1.
So the closest thing I could find is the “3PointLevels”. Sadly it’s a bit counterintuitive, e.g. you have to use input values <0 for black and >1 for white to achieve the effect described above.
EDIT: A better way at least seems to be setting black value to 0, white to 1, middle value between 0 and 1, and also connect the middle point with a value 0…1
In case of black and white textures (and probably color ones too), simply multiplying that texture by a value larger than one did the trick for me (Larger values - more contrast, smaller values - lower contrast).
Almotst 10 yrs later , still there is nothing remotely close to “color ramp” in unreal. , color ramp is too versatile tool to have , sure some one skilled enough can make a mat function , but the way you have to plug in all the threshold , numbers , is not intuitive at all.