我尝试在一个简单的应用程序中使用 Metal,但是当我调用
device.newDefaultLibrary()
函数时,我在运行时遇到错误:
/BuildRoot/Library/Caches/com.apple.xbs/Sources/Metal/Metal-56.7/Framework/MTLLibrary.mm:1842: 断言“未找到金属默认库”失败
有人知道问题出在哪里吗?我遵循了本教程。
代码有点旧,但稍作改动就可以了。这是我的
ViewController
代码:
import UIKit
import Metal
import QuartzCore
class ViewController: UIViewController {
//11A
var device: MTLDevice! = nil
//11B
var metalLayer: CAMetalLayer! = nil
//11C
let vertexData:[Float] = [
0.0, 1.0, 0.0,
-1.0, -1.0, 0.0,
1.0, -1.0, 0.0]
var vertexBuffer: MTLBuffer! = nil
//11F
var pipelineState: MTLRenderPipelineState! = nil
//11G
var commandQueue: MTLCommandQueue! = nil
//12A
var timer: CADisplayLink! = nil
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
//11A
device = MTLCreateSystemDefaultDevice()
//11B
metalLayer = CAMetalLayer() // 1
metalLayer.device = device // 2
metalLayer.pixelFormat = .BGRA8Unorm // 3
metalLayer.framebufferOnly = true // 4
metalLayer.frame = view.layer.frame // 5
view.layer.addSublayer(metalLayer) // 6
//11C
let dataSize = vertexData.count * sizeofValue(vertexData[0]) // 1
vertexBuffer = device.newBufferWithBytes(vertexData, length: dataSize, options: MTLResourceOptions.CPUCacheModeDefaultCache) // 2
//11F
// 1
let defaultLibrary = device.newDefaultLibrary() //The error is generating here
let fragmentProgram = defaultLibrary!.newFunctionWithName("basic_fragment")
let vertexProgram = defaultLibrary!.newFunctionWithName("basic_vertex")
// 2
let pipelineStateDescriptor = MTLRenderPipelineDescriptor()
pipelineStateDescriptor.vertexFunction = vertexProgram
pipelineStateDescriptor.fragmentFunction = fragmentProgram
pipelineStateDescriptor.colorAttachments[0].pixelFormat = .BGRA8Unorm
// 3
do {
try pipelineState = device.newRenderPipelineStateWithDescriptor(pipelineStateDescriptor)
} catch _ {
print("Failed to create pipeline state, error")
}
//11G
commandQueue = device.newCommandQueue()
//12A
timer = CADisplayLink(target: self, selector: Selector("gameloop"))
timer.addToRunLoop(NSRunLoop.mainRunLoop(), forMode: NSDefaultRunLoopMode)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
//MARK: Custom Methodes
//12A
func render() {
//12C
let commandBuffer = commandQueue.commandBuffer()
//12B
let drawable = metalLayer.nextDrawable()
let renderPassDescriptor = MTLRenderPassDescriptor()
renderPassDescriptor.colorAttachments[0].texture = drawable!.texture
renderPassDescriptor.colorAttachments[0].loadAction = .Clear
renderPassDescriptor.colorAttachments[0].clearColor = MTLClearColor(red: 0.0, green: 104.0/255.0, blue: 5.0/255.0, alpha: 1.0)
//12D
let renderEncoderOpt = commandBuffer.renderCommandEncoderWithDescriptor(renderPassDescriptor)
renderEncoderOpt.setRenderPipelineState(pipelineState)
renderEncoderOpt.setVertexBuffer(vertexBuffer, offset: 0, atIndex: 0)
renderEncoderOpt.drawPrimitives(.Triangle, vertexStart: 0, vertexCount: 3, instanceCount: 1)
renderEncoderOpt.endEncoding()
//12E
commandBuffer.presentDrawable(drawable!)
commandBuffer.commit()
}
func gameloop() {
autoreleasepool {
self.render()
}
}
}
我使用装有 iOS 9.3 的 iPhone 5s 设备进行测试。