MTLTexture+CVPixelBuffer (#73)

* add mtltexture to cvpixelbuffer conversion * update version to 0.11.6 * move extension to CVPixelFormat+MTLTexture.swift * remove unsused error type
s1ddok · Dec 19, 2019 · e146427 · e146427
1 parent 34338da
commit e146427
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diff --git a/Alloy.podspec b/Alloy.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name                  = 'Alloy'
-  s.version               = '0.11.5'
+  s.version               = '0.11.6'
   s.license               = { :type => 'MIT', :file => 'LICENSE' }
   s.summary               = 'Nano helpers for Metal framework'
   s.homepage              = 'https://github.com/s1ddok/Alloy'

diff --git a/Alloy/CVPixelBuffer+MTLTexture.swift b/Alloy/CVPixelBuffer+MTLTexture.swift
@@ -40,3 +40,42 @@ public extension MTLContext {
         return videoTextureCache
     }
 }
+
+public extension MTLTexture {
+
+    var pixelBuffer: CVPixelBuffer? {
+        guard let cvPixelFormat = self.pixelFormat
+                                      .compatibleCVPixelFormat
+        else { return nil }
+
+        var pb: CVPixelBuffer? = nil
+        var status = try CVPixelBufferCreate(nil,
+                                             self.width,
+                                             self.height,
+                                             cvPixelFormat,
+                                             nil,
+                                             &pb)
+        guard status == kCVReturnSuccess,
+              let pixelBuffer = pb
+        else { return nil }
+
+        status = CVPixelBufferLockBaseAddress(pixelBuffer, [])
+        guard status == kCVReturnSuccess,
+              let pixelBufferBaseAdress = CVPixelBufferGetBaseAddress(pixelBuffer)
+        else { return nil }
+
+        let bytesPerRow = CVPixelBufferGetBytesPerRow(pixelBuffer)
+
+        self.getBytes(pixelBufferBaseAdress,
+                      bytesPerRow: bytesPerRow,
+                      from: self.region,
+                      mipmapLevel: 0)
+
+        status = CVPixelBufferUnlockBaseAddress(pixelBuffer, [])
+        guard status == kCVReturnSuccess
+        else { return nil }
+
+        return pixelBuffer
+    }
+
+}
diff --git a/Alloy/MTLPixelFormat+CVPixelFormat.swift b/Alloy/MTLPixelFormat+CVPixelFormat.swift
@@ -0,0 +1,32 @@
+//
+//  MTLPixelFormat+CVPixelFormat.swift
+//  Alloy
+//
+//  Created by Eugene Bokhan on 19.12.2019.
+//
+
+import Metal
+
+public extension MTLPixelFormat {
+
+    var compatibleCVPixelFormat: OSType? {
+        switch self {
+        case .r8Unorm: return kCVPixelFormatType_OneComponent8
+        case .r16Float: return kCVPixelFormatType_OneComponent16Half
+        case .r32Float: return kCVPixelFormatType_OneComponent32Float
+
+        case .rg8Unorm: return kCVPixelFormatType_TwoComponent8
+        case .rg16Float: return kCVPixelFormatType_TwoComponent16Half
+        case .rg32Float: return kCVPixelFormatType_TwoComponent32Float
+
+        case .bgra8Unorm: return kCVPixelFormatType_32BGRA
+        case .rgba8Unorm: return kCVPixelFormatType_32RGBA
+        case .rgba16Float: return kCVPixelFormatType_64RGBAHalf
+        case .rgba32Float: return kCVPixelFormatType_128RGBAFloat
+
+        case .depth32Float: return kCVPixelFormatType_DepthFloat32
+        default: return nil
+        }
+    }
+
+}