Update CryptoKey documentation to mention ECC.

[basicer]

The documentation makes it seem like CryptoKey can only hold an RSA key. This is compounded by the fact that Cypto only has a function generate an RSA based key. Godot however is perfectly happy loading and using ECC based keys.

[basicer]

Example showing signing and verifying with an secp256k1 key.

var key = CryptoKey.new()
key.load_from_string("""-----BEGIN EC PRIVATE KEY-----
MHQCAQEEIGIumMFpusqAcqCkwN15oFS/QXNIf9LsmTCYMNwp9/G8oAcGBSuBBAAK
oUQDQgAEigp/7pvDMxn0mNDDuJuepWgWeXTw71jNk/aSo8LqyTSHXULaUbZh3G57
G3P3LqXcwRgm2Wz7J+9JoGzDokr1Pw==
-----END EC PRIVATE KEY-----""")

print(key.save_to_string())
print(key.save_to_string(true))
var pub = CryptoKey.new()
pub.load_from_string(key.save_to_string(true), true)

var ctx = HashingContext.new()
ctx.start(HashingContext.HASH_SHA256)
ctx.update("Hi!".to_ascii_buffer())
var hash = ctx.finish()


var sig = Crypto.new().sign(HashingContext.HASH_SHA256, hash, key)
print("SIG", sig)
print("Ok?", Crypto.new().verify(HashingContext.HASH_SHA256, hash, sig, pub))

[mhilbrunner]

As we're just passing this through to mbedtls, I'd expect both RSA and ECC to work, yes. Adding a link to the Crypto class for actually generating keys would also make sense. We should also add ECC key generation there. :) Would be worth opening an issue for.

[basicer]

We should also add ECC key generation there.

I was looking into this, but held off for now. It needs a bit of API design on how the user specifies which curve they want to use and also how to enumerate the available curves along with their bit size.

[akien-mga]

Could you amend the commit message to be more explicit, like the PR title?

Edit: Let me know if you're not familiar with how to do this with Git, I can also do this update myself.

[basicer]

@semensanyok Hi, does this fix work for you? I tried to follow your changes to modify this

case FORMAT_BPTC_RGBA:
	return 4; //btpc bc6h

Does it fix everything for you? Not working well for me, I am trying to figure out which part I get wrong.

there is also diff in drivers/gles3/storage/texture_storage.cpp in my PR (https://github.com/godotengine/godot/pull/91508), did you miss it by any chance? its not like your's

~~answering your question - yes it does, and switching layer in shader works for all profiles, loading all 4 layers for 4 textures correctly.~~

nope looks like its not fixed, cached version, keep looking. forward is broken currently by this draft

P.S. its wrong, 1 is correct value, forget this diff

[akien-mga]

Thanks!