Various improvements

submodules/TelegramUI/Components/MediaEditor/Sources/MediaEditorUtils.swift

@@ -1,4 +1,5 @@
 import Foundation
+import UIKit
 import AVFoundation
 import SwiftSignalKit
 
@@ -39,3 +40,92 @@ extension AVPlayer {
         return timer
     }
 }
+
+func textureRotatonForAVAsset(_ asset: AVAsset, mirror: Bool = false) -> TextureRotation {
+    for track in asset.tracks {
+        if track.mediaType == .video {
+            let t = track.preferredTransform
+            if t.a == -1.0 && t.d == -1.0 {
+                return .rotate180Degrees
+            } else if t.a == 1.0 && t.d == 1.0 {
+                return .rotate0Degrees
+            } else if t.b == -1.0 && t.c == 1.0 {
+                return .rotate270Degrees
+            }  else if t.a == -1.0 && t.d == 1.0 {
+                return .rotate270Degrees
+            } else if t.a == 1.0 && t.d == -1.0  {
+                return .rotate180Degrees
+            } else {
+                return mirror ? .rotate90DegreesMirrored : .rotate90Degrees
+            }
+        }
+    }
+    return .rotate0Degrees
+}
+
+func loadTexture(image: UIImage, device: MTLDevice) -> MTLTexture? {
+    func dataForImage(_ image: UIImage) -> UnsafeMutablePointer<UInt8> {
+        let imageRef = image.cgImage
+        let width = Int(image.size.width)
+        let height = Int(image.size.height)
+        let colorSpace = CGColorSpaceCreateDeviceRGB()
+        
+        let rawData = UnsafeMutablePointer<UInt8>.allocate(capacity: width * height * 4)
+        let bytePerPixel = 4
+        let bytesPerRow = bytePerPixel * Int(width)
+        let bitsPerComponent = 8
+        let bitmapInfo = CGBitmapInfo.byteOrder32Little.rawValue + CGImageAlphaInfo.premultipliedFirst.rawValue
+        let context = CGContext.init(data: rawData, width: width, height: height, bitsPerComponent: bitsPerComponent, bytesPerRow: bytesPerRow, space: colorSpace, bitmapInfo: bitmapInfo)
+        context?.draw(imageRef!, in: CGRect(x: 0, y: 0, width: width, height: height))
+        
+        return rawData
+    }
+    
+    let width = Int(image.size.width * image.scale)
+    let height = Int(image.size.height * image.scale)
+    let bytePerPixel = 4
+    let bytesPerRow = bytePerPixel * width
+    
+    var texture : MTLTexture?
+    let region = MTLRegionMake2D(0, 0, Int(width), Int(height))
+    let textureDescriptor = MTLTextureDescriptor.texture2DDescriptor(pixelFormat: .bgra8Unorm, width: width, height: height, mipmapped: false)
+    texture = device.makeTexture(descriptor: textureDescriptor)
+    
+    let data = dataForImage(image)
+    texture?.replace(region: region, mipmapLevel: 0, withBytes: data, bytesPerRow: bytesPerRow)
+    
+    return texture
+}
+
+func pixelBufferToMTLTexture(pixelBuffer: CVPixelBuffer, textureCache: CVMetalTextureCache) -> MTLTexture? {
+    let width = CVPixelBufferGetWidth(pixelBuffer)
+    let height = CVPixelBufferGetHeight(pixelBuffer)
+
+    let format: MTLPixelFormat = .r8Unorm
+    var textureRef : CVMetalTexture?
+    let status = CVMetalTextureCacheCreateTextureFromImage(nil, textureCache, pixelBuffer, nil, format, width, height, 0, &textureRef)
+    if status == kCVReturnSuccess {
+        return CVMetalTextureGetTexture(textureRef!)
+    }
+
+    return nil
+}
+
+func getTextureImage(device: MTLDevice, texture: MTLTexture, mirror: Bool = false) -> UIImage? {
+    let colorSpace = CGColorSpaceCreateDeviceRGB()
+    let context = CIContext(mtlDevice: device, options: [:])
+    guard var ciImage = CIImage(mtlTexture: texture, options: [.colorSpace: colorSpace]) else {
+        return nil
+    }
+    let transform: CGAffineTransform
+    if mirror {
+        transform = CGAffineTransform(-1.0, 0.0, 0.0, -1.0, ciImage.extent.width, ciImage.extent.height)
+    } else {
+        transform = CGAffineTransform(1.0, 0.0, 0.0, -1.0, 0.0, ciImage.extent.height)
+    }
+    ciImage = ciImage.transformed(by: transform)
+    guard let cgImage = context.createCGImage(ciImage, from: CGRect(origin: .zero, size: CGSize(width: ciImage.extent.width, height: ciImage.extent.height))) else {
+        return nil
+    }
+    return UIImage(cgImage: cgImage)
+}