Add project files.

Assets/Cryville/Common/Pdt/PdtVariableMemory.cs

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+using System;
+using System.Text;
+using UnityEditor;
+
+namespace Cryville.Common.Pdt {
+	/// <summary>
+	/// Span on the memory of a <see cref="PdtEvaluatorBase" />.
+	/// </summary>
+	public unsafe struct PdtVariableMemory {
+		byte* _ptr;
+		/// <summary>
+		/// The length of the span.
+		/// </summary>
+		public int Length { get; private set; }
+		/// <summary>
+		/// The type of the span.
+		/// </summary>
+		public int Type { get; private set; }
+		internal PdtVariableMemory(int type, byte* ptr, int len) {
+			Type = type;
+			_ptr = ptr;
+			Length = len;
+		}
+		/// <summary>
+		/// Copies the memory in the span to a buffer.
+		/// </summary>
+		/// <param name="dest">The destination buffer.</param>
+		/// <param name="destOffset">The offset on the destination buffer to start copying to.</param>
+		public void CopyTo(byte[] dest, int destOffset) {
+			fixed (byte* ptr = dest) {
+				CopyTo(ptr, destOffset, Length);
+			}
+		}
+		/// <summary>
+		/// Copies the memory in the span to a buffer.
+		/// </summary>
+		/// <param name="dest">The destination buffer.</param>
+		/// <param name="destOffset">The offset on the destination buffer to start copying to.</param>
+		/// <param name="length">The length to copy.</param>
+		public void CopyTo(byte* dest, int destOffset, int length) {
+			for (int i = 0; i < length; i++)
+				dest[destOffset + i] = _ptr[i];
+		}
+		/// <summary>
+		/// Gets the memory of the span as a number.
+		/// </summary>
+		/// <returns>A number.</returns>
+		/// <exception cref="InvalidCastException">The span does not represent a number.</exception>
+		public float AsNumber() {
+			if (Type != PdtInternalType.Number)
+				throw new InvalidCastException("Not a number");
+			float value;
+			byte* ptr = (byte*)&value;
+			for (int i = 0; i < sizeof(float); i++)
+				ptr[i] = _ptr[i];
+			return value;
+		}
+		/// <summary>
+		/// Sets the memory of the span to a number.
+		/// </summary>
+		/// <param name="value">The number.</param>
+		/// <exception cref="InvalidCastException">The span does not represent a number.</exception>
+		public void SetNumber(float value) {
+			if (Type != PdtInternalType.Number)
+				throw new InvalidCastException("Not a number");
+			byte* ptr = (byte*)&value;
+			for (int i = 0; i < sizeof(float); i++)
+				_ptr[i] = ptr[i];
+		}
+		/// <summary>
+		/// Gets the memory of the span as a string.
+		/// </summary>
+		/// <param name="offset">The offset on the span to start reading from.</param>
+		/// <returns>A string.</returns>
+		/// <exception cref="InvalidCastException">The span at the offset does not represent a string.</exception>
+		public string AsString(int offset = 0) {
+			if (Type != PdtInternalType.String && Type != PdtInternalType.Array)
+				throw new InvalidCastException("Not a string");
+			var len = *(int*)(_ptr + offset);
+			return new string((char*)(_ptr + offset + sizeof(int)), 0, len);
+		}
+		/// <summary>
+		/// Sets the memory of the span to a string.
+		/// </summary>
+		/// <param name="value">The string.</param>
+		/// <param name="offset">The offset from the start of the span.</param>
+		/// <exception cref="InvalidCastException">The span at the offset does not represent a string.</exception>
+		/// <exception cref="InvalidOperationException">The length of the span is not sufficient.</exception>
+		public void SetString(string value, int offset = 0) {
+			if (Type != PdtInternalType.String && Type != PdtInternalType.Array)
+				throw new InvalidCastException("Not a string");
+			int strlen = value.Length;
+			if (Length < strlen * sizeof(char) + sizeof(int) + offset)
+				throw new InvalidOperationException("Frame length not sufficient");
+			char* ptr = (char*)(_ptr + offset + sizeof(int));
+			*(int*)(_ptr + offset) = strlen;
+			int i = 0;
+			foreach (var c in value) ptr[i++] = c;
+		}
+		/// <summary>
+		/// Gets the memory of the span as an undefined identifier.
+		/// </summary>
+		/// <param name="offset">The offset on the span to start reading from.</param>
+		/// <returns>The name of an undefined identifier.</returns>
+		/// <exception cref="InvalidCastException">The span does not represent an undefined identifier.</exception>
+		public string AsIdentifier(int offset = 0) {
+			if (Type != PdtInternalType.Undefined && Type != PdtInternalType.Array)
+				throw new InvalidCastException("Not an identifier");
+			var len = *(int*)(_ptr + offset);
+			return new string((char*)(_ptr + offset + sizeof(int)), 0, len);
+		}
+		internal void* TrustedAsOfLength(int len) {
+			if (Length < len)
+				throw new InvalidCastException("Type not matched");
+			return _ptr;
+		}
+		/// <summary>
+		/// Gets the array suffix.
+		/// </summary>
+		/// <param name="arrtype">The type of the array.</param>
+		/// <param name="pc">The item count of the array.</param>
+		/// <exception cref="InvalidCastException">The span does not represent an array.</exception>
+		public void GetArraySuffix(out int arrtype, out int pc) {
+			if (Type != PdtInternalType.Array && Type != PdtInternalType.Array)
+				throw new InvalidCastException("Not an array or vector");
+			arrtype = *(int*)(_ptr + Length - sizeof(int));
+			if (Type == PdtInternalType.Array) pc = *(int*)(_ptr + Length - 2 * sizeof(int));
+			else pc = -1;
+		}
+		/// <summary>
+		/// Sets the array suffix.
+		/// </summary>
+		/// <param name="arrtype">The type of the array.</param>
+		/// <param name="pc">The item count of the array.</param>
+		/// <exception cref="InvalidCastException">The span does not represent an array.</exception>
+		public void SetArraySuffix(int arrtype, int pc = 0) {
+			if (Type != PdtInternalType.Vector && Type != PdtInternalType.Array)
+				throw new InvalidCastException("Not an array or vector");
+			*(int*)(_ptr + Length - sizeof(int)) = arrtype;
+			if (Type == PdtInternalType.Array) *(int*)(_ptr + Length - 2 * sizeof(int)) = pc;
+		}
+	}
+}