Moved CPUAccessFlags and Usage to seperate file

GlitchyEngine/src/Renderer/Usage.bf

@@ -0,0 +1,29 @@
+namespace GlitchyEngine.Renderer
+{
+	/**
+	 * Identifies expected resource use during rendering.
+	 * The usage directly reflects whether a resource is accessible by the CPU and/or the graphics processing unit (GPU). 
+	 */
+	public enum Usage
+	{
+		/**
+		 * A resource that requires read and write access by the GPU.
+		 * This is likely to be the most common usage choice. 
+		 */
+		Default	= 0,
+		/**
+		 * A resource that can only be read by the GPU. It cannot be written by the GPU, and cannot be accessed at all by the CPU.
+		 */
+		Immutable = 1,
+		/**
+		 * A resource that is accessible by both the GPU (read only) and the CPU (write only). 
+		 * A dynamic resource is a good choice for a resource that will be updated by the CPU at least once per frame. 
+		 * To update a dynamic resource, use a Map method.
+		 */
+		Dynamic = 2,
+		/**
+		 * A resource that supports data transfer (copy) from the GPU to the CPU.
+		 */
+		Staging = 3
+	}
+}