/// <summary>
/// Initializes the <see cref="For{T}"/> shared state.
/// </summary>
/// <param name="factory">The factory of <see cref="ID2D1TransformMapper{T}"/> instances to use for each created effect.</param>
/// <exception cref="InvalidOperationException">Thrown if initialization is attempted with a mismatched transform factory.</exception>
public static void Initialize(Func <ID2D1TransformMapper <T> >?factory)
{
// This conceptually acts as a static constructor, and this type is
// internal, so in this very specific case locking on the type is fine.
lock (typeof(For <T>))
{
if (isInitialized)
{
// If the factory is already initialized, ensure the draw transform mapper is the same
if (d2D1DrawTransformMapperFactory != factory)
{
ThrowHelper.ThrowInvalidOperationException(
"Cannot initialize an ID2D1Effect factory for the same shader type with two different transform mappings. " +
"Make sure to only ever register a pixel shader effect with either no transform, or the same transform type.");
}
}
else
{
// Load all shader properties
Guid guid = typeof(T).GUID;
int inputCount = (int)D2D1InteropServices.GetPixelShaderInputCount <T>();
ReadOnlyMemory <byte> buffer = D2D1InteropServices.LoadPixelShaderBytecode <T>();
byte *typeAssociatedMemory = (byte *)RuntimeHelpers.AllocateTypeAssociatedMemory(typeof(For <T>), buffer.Length);
// Copy the bytecode to the target buffer
buffer.Span.CopyTo(new Span <byte>(typeAssociatedMemory, buffer.Length));
// Set the shared state and mark the type as initialized
shaderId = guid;
numberOfInputs = inputCount;
bytecode = typeAssociatedMemory;
bytecodeSize = buffer.Length;
d2D1DrawTransformMapperFactory = factory;
isInitialized = true;
}
}
}
public unsafe void GetInputCount()
{
Assert.AreEqual(D2D1InteropServices.GetPixelShaderInputCount <InvertEffect>(), 1u);
Assert.AreEqual(D2D1InteropServices.GetPixelShaderInputCount <PixelateEffect.Shader>(), 1u);
Assert.AreEqual(D2D1InteropServices.GetPixelShaderInputCount <ZonePlateEffect>(), 0u);
}
