在上一篇(視頻播放)中隔盛，如果放入的視頻不是16:9, 會發(fā)現(xiàn)圖像的形狀會被拉伸，要解決這個問題只需要修改頂點數(shù)據(jù)就可以了拾稳。

上代碼

...
let wY = CVPixelBufferGetWidthOfPlane(pixelBuffer, 0)
let hY = CVPixelBufferGetHeightOfPlane(pixelBuffer, 0)
let vs = transformVertices(vertex: vertexs, inputSize: CGSize(width: wY, height: hY), drawableSize: mtkView.drawableSize)
let vertexBuffer = device.makeBuffer(bytes: vs, length: MemoryLayout<Float>.size * 8, options: [])
let textureVerBuffer = device.makeBuffer(bytes: textureCoordinates, length: MemoryLayout<Float>.size * 8, options: [])
renderCommandEncoder.setVertexBuffer(vertexBuffer, offset: 0, index: 0)
renderCommandEncoder.setVertexBuffer(textureVerBuffer, offset: 0, index: 1)
...

/// 頂點轉(zhuǎn)換
    func transformVertices(vertex: [Float], inputSize: CGSize, drawableSize: CGSize) -> [Float] {
        
        let inputAspectRatio = inputSize.height / inputSize.width
        let drawableAspectRatio = drawableSize.height / drawableSize.width
        
        var xRatio: Float = 1.0
        var yRatio: Float = 1.0
        
        if inputAspectRatio > drawableAspectRatio {
            yRatio = 1.0
            xRatio = Float((inputSize.width / drawableSize.width) * (drawableSize.height / inputSize.height))
        }else {
            xRatio = 1.0
            yRatio = Float((inputSize.height / drawableSize.height) * (drawableSize.width / inputSize.width))
        }
        
        let value1 = vertex[0] * xRatio
        let value2 = vertex[1] * yRatio
        
        let value3 = vertex[2] * xRatio
        let value4 = vertex[3] * yRatio
        
        let value5 = vertex[4] * xRatio
        let value6 = vertex[5] * yRatio
        
        let value7 = vertex[6] * xRatio
        let value8 = vertex[7] * yRatio
        
        return [value1, value2, value3, value4, value5, value6, value7, value8]
    }

經(jīng)過轉(zhuǎn)換之后吮炕，就可以正常的顯示圖像，如下：

IMG_0066.PNG

具體實現(xiàn)已經(jīng)更新到Metal-10(視頻播放)中访得。