Using the GradientRamp procedural texture map in Mapped mode can very useful for creating procedural material effects.
The Idea is that the lightness value from a different map will determine what part of the GradientRamp is sampled.
In this example the GradientRamp uses values produced by a procedural Falloff map set to Perpendicular-Parallel mode, as its coordinates source, to create richly colored metal that changes its Hue depending on View/Incident angle:
In this example the GradientRamp uses values produced by a procedural Noise map as its coordinates source to create an irregular color effect:
The examples here were rendered using V-Ray Next for 3ds max, but this technique could also be used with other rendering engines.
When you need a solid color source or background for your composite,
The Background node is just that,
It provides either a flat color plate or 4 types of gradients (color ramps).
Set the plate fill type in the Color tab of the node’s settings, and the format (size) in the Image tab.
One of the optical properties of many metallic surfaces is changing it’s color slightly as the surface viewing angle changes.
This effect can be simply created using a Fresnel node and a color-ramp texture.
Create a metallic material (metallic value of 1.0).
Use an image editing software to create a linear color ramp texture (gradient) of the color change per viewing angle from left to right. like this example for a golden metal, and import it to your project.
Add the ramp texture to the material Blueprint, and connect it to the material Base Color Input.
Create aFresnel node and set its Exponent value to 1.0 and its Base Reflect Fraction to a value of 0.0 so it will provide a linear angle blend value.
Connect the Fresnel node’s output to the UVs input of the ramp texture node.
* the reason the Fresnel node can be providing both the X and Y texture coordinates is that the texture’s Y dimension provides the same color for all values anyway.
When the Metallic property of an Unreal Engine material is set to 1.0, the material automatically simulates the metal’s color fading to white at parallel surface viewing angle (the sides) like it should.
So using a Color Ramp Texture like in this example creates an amplified effect.
* Simply put: You don’t have to have the Color Ramp fade to white on the right side of the texture..