Add texture support to HardwareVideoEncoder.

webrtc/sdk/android/api/org/webrtc/RendererCommon.java

 /*
  *  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 255 matching lines @@
         matrix4x4[0 * 4 + 1], matrix4x4[1 * 4 + 1], matrix4x4[3 * 4 + 1],
         matrix4x4[0 * 4 + 3], matrix4x4[1 * 4 + 3], matrix4x4[3 * 4 + 3],
     };
     // clang-format on
 
     android.graphics.Matrix matrix = new android.graphics.Matrix();
     matrix.setValues(values);
     return matrix;
   }
 
+  /** Converts android.graphics.Matrix to a float[16] matrix array. */
+  public static float[] convertMatrixFromAndroidGraphicsMatrix(android.graphics.Matrix matrix) {
+    float[] values = new float[9];
+    matrix.getValues(values);
+
+    // 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]
+    // clang-format off
+    float[] matrix4x4 = {
+        values[0 * 3 + 0],  values[1 * 3 + 0], 0,  values[2 * 3 + 0],
+        values[0 * 3 + 1],  values[1 * 3 + 1], 0,  values[2 * 3 + 1],
+        0,                  0,                 1,  0,
+        values[0 * 3 + 2],  values[1 * 3 + 2], 0,  values[2 * 3 + 2],
+    };
+    // clang-format on
+    return matrix4x4;
+  }
+
   /**
    * Calculate display size based on scaling type, video aspect ratio, and maximum display size.
    */
   public static Point getDisplaySize(
       ScalingType scalingType, float videoAspectRatio, int maxDisplayWidth, int maxDisplayHeight) {
     return getDisplaySize(convertScalingTypeToVisibleFraction(scalingType), videoAspectRatio,
         maxDisplayWidth, maxDisplayHeight);
   }
 
   /**
@@ skipping 38 matching lines @@
       return new Point(maxDisplayWidth, maxDisplayHeight);
     }
     // Each dimension is constrained on max display size and how much we are allowed to crop.
     final int width = Math.min(
         maxDisplayWidth, Math.round(maxDisplayHeight / minVisibleFraction * videoAspectRatio));
     final int height = Math.min(
         maxDisplayHeight, Math.round(maxDisplayWidth / minVisibleFraction / videoAspectRatio));
     return new Point(width, height);
   }
 }