Metal: Metal Resources

Metal Resources

• MTLBuffer : 모든 데이터 타입을 포함하 ㄹ수 있는 unformatted 메모리 할당
• MTLTexture : formatted 이미지 데이터 할당

 

Argument Table

Shader Parameters와 Resources 사이의 매핑 (Encoder와 Shader 사이의 연결)

• Buffers
• Textures
• Sampler states

 

Buffer

Buffer 생성

makeBuffer(length:options:)
makeBuffer(bytes:length:options:)
makeBuffer(bytesNoCopy:length:options:deallocator:)

 

MTLVertexDescriptor

vertexDescriptor.attributes[0].offset = 0
vertexDescriptor.attributes[0].format = .float3 // position
vertexDescriptor.attributes[1].offset = 12
// Vertex normal
vertexDescriptor.attributes[1].format = MTLVertexFormat.float3
vertexDescriptor.layouts[0].stride = 24

let pipelineStateDescriptor = MTLRenderPipelineDescriptor()
pipelineStateDescriptor.vertexDescriptor = vertexDescriptor

 

Texture

Texture 생성

newTextureWithDescriptor
makeTextureView(pixelFormat:)
newTextureWithDescriptor:offset:bytesPerRow

 

MTKTextureLoader로 이미지 데이터 로드

if let textureUrl = NSURL(string: fileLocation) {
    let textureLoader = MTKTextureLoader(device: device)
    do {
		diffuseTexture = try textureLoader.newTextureWithContentsOfURL(textureUrl, options: nil)
  	} catch _ {
       print("diffuseTexture assignment failed")
	}
}

 

Texture 카피

func getBytes(_ pixelBytes: UnsafeMutableRawPointer,
              bytesPerRow: Int,
              from region: MTLRegion,
              mipmapLevel level: Int)
              
func replace(region: MTLRegion,
             mipmapLevel level: Int,
             slice: Int,
             withBytes pixelBytes: UnsafeRawPointer,
             bytesPerRow: Int,
             bytesPerImage: Int)

 

MTLBlitCommandEncoder

한 위치에서 다른 위치로 데이터 복사

func copy(from sourceBuffer: MTLBuffer,
          sourceOffset: Int,
          to destinationBuffer: MTLBuffer,
          destinationOffset: Int,
          size: Int)
          
func copy(from sourceBuffer: MTLBuffer,
          sourceOffset: Int,
          sourceBytesPerRow: Int,
          sourceBytesPerImage: Int,
          sourceSize: MTLSize,
          to destinationTexture: MTLTexture,
          destinationSlice: Int,
          destinationLevel: Int,
          destinationOrigin: MTLOrigin)