Fix fromAndroidGraphicsMatrix to use column-major order for output.

webrtc/sdk/android/src/jni/native_handle_impl.cc

 /*
  *  Copyright 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 34 matching lines @@
   memset(matrix.elem_, 0, sizeof(matrix.elem_));
   // The android.graphics.Matrix looks like this:
   // [x1 y1 w1]
   // [x2 y2 w2]
   // [x3 y3 w3]
   // We want to contruct a matrix that looks like this:
   // [x1 y1  0 w1]
   // [x2 y2  0 w2]
   // [ 0  0  1  0]
   // [x3 y3  0 w3]
+  // Since it is stored in column-major order, it looks like this:
+  // [x1 x2 0 x3
+  //  y1 y2 0 y3
+  //   0  0 1  0
+  //  w1 w2 0 w3]
   matrix.elem_[0 * 4 + 0] = array_3x3_ptr[0 * 3 + 0];
-  matrix.elem_[0 * 4 + 1] = array_3x3_ptr[0 * 3 + 1];
-  matrix.elem_[0 * 4 + 3] = array_3x3_ptr[0 * 3 + 2];
-  matrix.elem_[1 * 4 + 0] = array_3x3_ptr[1 * 3 + 0];
+  matrix.elem_[0 * 4 + 1] = array_3x3_ptr[1 * 3 + 0];
+  matrix.elem_[0 * 4 + 3] = array_3x3_ptr[2 * 3 + 0];
+  matrix.elem_[1 * 4 + 0] = array_3x3_ptr[0 * 3 + 1];
   matrix.elem_[1 * 4 + 1] = array_3x3_ptr[1 * 3 + 1];
-  matrix.elem_[1 * 4 + 3] = array_3x3_ptr[1 * 3 + 2];
+  matrix.elem_[1 * 4 + 3] = array_3x3_ptr[2 * 3 + 1];
   matrix.elem_[2 * 4 + 2] = 1;  // Z-scale should be 1.
-  matrix.elem_[3 * 4 + 0] = array_3x3_ptr[2 * 3 + 0];
-  matrix.elem_[3 * 4 + 1] = array_3x3_ptr[2 * 3 + 1];
+  matrix.elem_[3 * 4 + 0] = array_3x3_ptr[0 * 3 + 2];
+  matrix.elem_[3 * 4 + 1] = array_3x3_ptr[1 * 3 + 2];
   matrix.elem_[3 * 4 + 3] = array_3x3_ptr[2 * 3 + 2];
   return matrix;
 }
 
 jfloatArray Matrix::ToJava(JNIEnv* jni) const {
   jfloatArray matrix = jni->NewFloatArray(16);
   jni->SetFloatArrayRegion(matrix, 0, 16, elem_);
   return matrix;
 }
 
@@ skipping 266 matching lines @@
     int height,
     const Matrix& matrix,
     jobject j_video_frame_buffer) const {
   JNIEnv* jni = AttachCurrentThreadIfNeeded();
   return new rtc::RefCountedObject<AndroidVideoBuffer>(
       jni, j_retain_id_, j_release_id_, width, height, matrix,
       j_video_frame_buffer);
 }
 
 }  // namespace webrtc_jni