Is there practical examples of Half-float (FP16) ?

Does it affect automatic filtering (GL_SAMPLES, GL_LINEAR_MIPMAP_LINEAR, Anisotropic extensions) or only hand-written filtering algorithms ?

It will affect everything; it's just a problem with quantization causing less accurate sample points with higher floating point values (as the exponent gets bigger you get fewer and fewer decimal places).

I mean, can the visual quality of some applied textures be improved by just setting precision highp float; instead of precision mediump float; in the fragment shader and sending fp32 coordinates ?

Potentially yes; it depends how the texture is being used (do you have UV wrapping), and on the size of the texture (bigger texture = more pixels to cover with the same 0-1 number range, so effectively less bits per pixel). The driver can help automatically here (we know what inputs are used as texture coordinates), so we can prevent the worst of the issues without the application changing anything.

Does it affect automatic filtering (GL_SAMPLES, GL_LINEAR_MIPMAP_LINEAR, Anisotropic extensions) or only hand-written filtering algorithms ?

It will affect everything; it's just a problem with quantization causing less accurate sample points with higher floating point values (as the exponent gets bigger you get fewer and fewer decimal places).

I mean, can the visual quality of some applied textures be improved by just setting precision highp float; instead of precision mediump float; in the fragment shader and sending fp32 coordinates ?

Potentially yes; it depends how the texture is being used (do you have UV wrapping), and on the size of the texture (bigger texture = more pixels to cover with the same 0-1 number range, so effectively less bits per pixel). The driver can help automatically here (we know what inputs are used as texture coordinates), so we can prevent the worst of the issues without the application changing anything.

Thanks for these clarifications !

That said, what would be the general best practices for good CPU←→GPU bandwidth usage while retaining enough quality then ?

FP32 (Highp) for close range / high detail assets and (FP16) Mediump for landscape and random filling decoration, I guess ?

See previous answer:

In general for anything related to position (texture coordinates, vertex positions, uniform matrices for position transform, distance computation for lighting, etc) we'd generally recommend using highp/fp32. For anything related to color, or intermediate values which will turn in to a color at some point (such as normals for lighting) then fp16 is probably fine.

=)

Alright then