This is the documentation for Enlighten.

Reserved texture samplers

When a material is used with Enlighten lightmaps, the number of texture samples allowed in the material is reduced. This can cause an error when compiling the shaders for a material with many texture samples.


When a material has Used With Enlighten Lightmaps selected in Details > Usage:

  • the number of available texture samplers is reduced
  • if the target shader profile supports shared samplers, only one sampler is reserved
  • if the target shader profile doesn't support shared samplers, the number of reserved samplers increases with the Lightmap Display Quality chosen in Project Settings > Enlighten
(Mobile) Lightmap Display Quality

SM5

SM4

METAL_MRT

METAL_SM4

ES2

METAL

High

1

1

1

1

3

4

Medium

1

1

1

1

2

3

Low

1

1

1

1

1

2

If you know the material is never used with a mesh that's lit using lightmaps, disable Used With Enlighten Lightmaps to increase the number of available texture samplers.