public void MaskedMemCpy_EndToEnd_HasExpectedValueAfterMemMask()
{
// see: MaskedMemCpy_MaskedMemCopyTestsData_HasExpectedMask for the prerequisites:
// --> we got a size of 12 bytes for the test data, 16 byte block size thus 48 byte of mask block data.
MaskedMemCpy_MaskedMemCopyTestsData_HasExpectedMask(); // adding test here such that it can not get removed accidentally.
// we generate some test data (24 bytes, which will initially set all padding to zero), and hash it.
// then we mess up the padding bytes, we hash again which will give a different value. (assert#1)
// we assert (AssertMemberwiseEqual) that we actually did not change any members (padding is transparent when accessing the members)
// finally we apply the expected padding mask which should bring back everything to the original state
const int seed = 0x72;
var testData0 = new MemMaskTestData_Mask
{
Offset0 = true,
Offset4 = 0x19abcdef,
Offset8 = true
};
var testData1 = new MemMaskTestData_Mask
{
Offset0 = true,
Offset4 = 0x01abcdef,
Offset8 = true
};
var mask = Masks.GetMaskView <MemMaskTestData_Mask>();
using (var _ = new NativeArray <MemMaskTestData_Mask>(2, Allocator.Persistent))
{
var data = _;
data[0] = testData0;
data[1] = testData1;
var view = NativeViewUtility.GetReadView(data);
var h0 = HashUtility.GetDenseHash(view, seed);
MessUpPaddingBytes(view, mask);
var h1 = HashUtility.GetDenseHash(view, seed);
Assert.AreNotEqual(h0, h1);
AssertMemberwiseEqual(testData0, data[0]);
AssertMemberwiseEqual(testData1, data[1]);
MaskedMemCopy.ApplyMask(view, mask);
Assert.AreEqual(h0, HashUtility.GetDenseHash(view, seed));
}
}
void MessUpPaddingBytes(NativeView view, NativeView mask)
{
var maskLength = mask.LengthInBytes;
for (int i = 0; i < view.LengthInBytes; i++)
{
var maskIndex = i % maskLength;
var isUnused = NativeViewUtility.ReadByte(mask, maskIndex) == 0;
if (isUnused)
{
NativeViewUtility.WriteByte(view, i, (byte)i);
}
}
}
public void HashUtility_ZeroPadding_EntityWithBufferEndToEnd_HasExpectedHash()
{
using (var world = new World("HashUtilityTests_BufferTestWorld"))
{
var bufferElement = new HashUtilityTest_BufferElement {
Offset0 = true, Offset4 = 0xBeef
};
var entity = world.EntityManager.CreateEntity();
var buffer = world.EntityManager.AddBuffer <HashUtilityTest_BufferElement>(entity);
buffer.Add(bufferElement);
using (var chunks = world.EntityManager.GetAllChunks(Allocator.Persistent))
{
Assert.AreEqual(chunks.Length, 1);
var chunk = chunks[0];
using (var types = chunk.GetNonzeroComponentTypes(Allocator.Persistent))
{
Assert.AreEqual(types.Length, 2 /* Entity, HashUtilityTest_BufferElement */);
using (var _ = new NativeArray <uint>(3, Allocator.Persistent))
{
var hashes = _;
hashes[0] = HashUtility.GetDenseHash(NativeViewUtility.GetView(ref entity), SeedForTesting);
var mask = NativeViewUtility.GetReadView(Masks.GetTypeMask <HashUtilityTest_BufferElement>());
var bufferHash = HashUtility.GetMaskedHash(NativeViewUtility.GetView(ref bufferElement), mask, SeedForTesting);
hashes[1] = HashUtility.GetDenseHash(NativeViewUtility.GetView(ref bufferHash), SeedForTesting);
hashes[2] = HashUtility.GetChunkHeaderHash(chunk, SeedForTesting);
using (var expected = HashUtility.GetChunkHashes(chunk, MaskedHasher, SeedForTesting))
{
Assert.That(hashes, Is.EquivalentTo(expected), DeterminismTestUtility.PrintAll(hashes, expected));
}
}
}
}
}
}
static uint MimicChunkedLocalToWorldHash(LocalToWorld ltw, uint seed)
{
var h = HashUtility.GetDenseHash(NativeViewUtility.GetView(ref ltw), seed);
return(HashUtility.GetDenseHash(NativeViewUtility.GetView(ref h), seed));
}
