Crisper minimap in case of SSAA

[lhog]

• Minor MiniMap code cleaning
• Retain minimap sharpness in case of SSAA (non-zero MinSampleShadingRate)
• Alternative to Fix blurred minimap #1897

[lhog]

@bcdrme any comments / objections to this approach?

Engine release 2025.01.6:
MinSampleShadingRate 0

MinSampleShadingRate 1

This PR:
MinSampleShadingRate 0

MinSampleShadingRate 1

[bcdrme]

That looks perfect ! Thank you for taking the time.

edit: tested in game, looking good 👍

auto state = GL::SubState(
  Blending(GL_FALSE),
  SampleShading(GL_FALSE) // sample shading is detrimental for minimap background sharpness
);

I suppose the above could also be applied to rmlui
for reference #1901

[lhog]

Yeah it might work for #1901, though I'm less certain about the cause there.
Worth trying though.