Ramp shading is another option that compares well with basic Cell shading. By using a ramp to decide the color and intensity of the light, we can gain more control of the light-dark transition. Here is Cell Shading on the Left and Ramp Shading on the ramp with an equivalent ramp texture. The main benefit we can immediately notice is the softening of transitions. Cell shading can introduce aliasing and ramp shading smooths this somewhat.
Since the lighting is now governed by a ramp, we can easily control the brightness and falloff of the lighting. It also allows us to easily create various effects as seen below:
 Basic Ramp
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 + Gaussian Blur
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 +Blurred Mid tones and Gaussian Blur
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Maya CGFX File:
| rampshading.cgfx |
Unity SHADER File:
| rampshading.shader |