wip Move SurfaceTexture.updateTexImage() from video renderers into MediaCodecVideoDecoder

talk/app/webrtc/java/src/org/webrtc/VideoRenderer.java

Index: talk/app/webrtc/java/src/org/webrtc/VideoRenderer.java
diff --git a/talk/app/webrtc/java/src/org/webrtc/VideoRenderer.java b/talk/app/webrtc/java/src/org/webrtc/VideoRenderer.java
index afda84897cbe43b98548f219dfe6e8694a937ed0..0628d05f1218a391e3855ebc36aaa40590e70e5c 100644
--- a/talk/app/webrtc/java/src/org/webrtc/VideoRenderer.java
+++ b/talk/app/webrtc/java/src/org/webrtc/VideoRenderer.java
@@ -39,12 +39,23 @@ public class VideoRenderer {
 
   /** Java version of cricket::VideoFrame. Frames are only constructed from native code. */
   public static class I420Frame {
+    // Matrix with transform y' = 1 - y.
+    private static final float[] VERTICAL_FLIP = new float[] {
+        1,  0, 0, 0,
+        0, -1, 0, 0,
+        0,  0, 1, 0,
+        0,  1, 0, 1};
+
     public final int width;
     public final int height;
     public final int[] yuvStrides;
     public ByteBuffer[] yuvPlanes;
     public final boolean yuvFrame;
-    public Object textureObject;
+    // Matrix that transforms standard coordinates to their proper sampling locations in
+    // the texture. This transform compensates for any properties of the video source that
+    // cause it to appear different from a normalized texture. This matrix does not take
+    // |rotationDegree| into account.
+    public final float[] samplingMatrix;
     public int textureId;
     // Frame pointer in C++.
     private long nativeFramePointer;
@@ -65,6 +76,9 @@ public class VideoRenderer {
       this.yuvPlanes = yuvPlanes;
       this.yuvFrame = true;
       this.rotationDegree = rotationDegree;
+      // For ByteBuffers, row 0 specifies the top row, but for a texture, row 0 specifies the
+      // bottom row. Sample the texture with a vertical flip to compensate for this.
+      this.samplingMatrix = VERTICAL_FLIP;
       this.nativeFramePointer = nativeFramePointer;
       if (rotationDegree % 90 != 0) {
         throw new IllegalArgumentException("Rotation degree not multiple of 90: " + rotationDegree);
@@ -76,12 +90,12 @@ public class VideoRenderer {
      */
     private I420Frame(
         int width, int height, int rotationDegree,
-        Object textureObject, int textureId, long nativeFramePointer) {
+        int textureId, float[] samplingMatrix, long nativeFramePointer) {
       this.width = width;
       this.height = height;
       this.yuvStrides = null;
       this.yuvPlanes = null;
-      this.textureObject = textureObject;
+      this.samplingMatrix = samplingMatrix;
       this.textureId = textureId;
       this.yuvFrame = false;
       this.rotationDegree = rotationDegree;
@@ -124,7 +138,6 @@ public class VideoRenderer {
     */
    public static void renderFrameDone(I420Frame frame) {
      frame.yuvPlanes = null;
-     frame.textureObject = null;
      frame.textureId = 0;
      if (frame.nativeFramePointer != 0) {
        releaseNativeFrame(frame.nativeFramePointer);