Android video rendering: Apply SurfaceTexture.getTransformationMatrix()

talk/app/webrtc/androidtests/src/org/webrtc/RendererCommonTest.java

 /*
  * libjingle
  * Copyright 2015 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 17 matching lines @@
 package org.webrtc;
 
 import android.test.ActivityTestCase;
 import android.test.MoreAsserts;
 import android.test.suitebuilder.annotation.SmallTest;
 
 import android.graphics.Point;
 
 import static org.webrtc.RendererCommon.ScalingType.*;
 import static org.webrtc.RendererCommon.getDisplaySize;
-import static org.webrtc.RendererCommon.getTextureMatrix;
+import static org.webrtc.RendererCommon.getLayoutMatrix;
+import static org.webrtc.RendererCommon.getSamplingMatrix;
 
 public class RendererCommonTest extends ActivityTestCase {
   @SmallTest
   static public void testDisplaySizeNoFrame() {
     assertEquals(getDisplaySize(SCALE_ASPECT_FIT, 0.0f, 0, 0), new Point(0, 0));
     assertEquals(getDisplaySize(SCALE_ASPECT_FILL, 0.0f, 0, 0), new Point(0, 0));
     assertEquals(getDisplaySize(SCALE_ASPECT_BALANCED, 0.0f, 0, 0), new Point(0, 0));
   }
 
   @SmallTest
@@ skipping 44 matching lines @@
   // Only keep 2 rounded decimals to make float comparison robust.
   static private double[] round(float[] array) {
     assertEquals(array.length, 16);
     final double[] doubleArray = new double[16];
     for (int i = 0; i < 16; ++i) {
       doubleArray[i] = Math.round(100 * array[i]) / 100.0;
     }
     return doubleArray;
   }
 
+  // Brief summary about matrix transformations:
+  // A coordinate p = [u, v, 0, 1] is transformed by matrix m like this p' = [u', v', 0, 1] = m * p.
+  // OpenGL uses column-major order, so:
+  // u' = u * m[0] + v * m[4] + m[12].
+  // v' = u * m[1] + v * m[5] + m[13].
+
   @SmallTest
-  static public void testTexMatrixDefault() {
-    final float texMatrix[] = new float[16];
-    getTextureMatrix(texMatrix, 0, false, 1.0f, 1.0f);
-    // TODO(magjed): Every tex matrix contains a vertical flip, because we ignore the texture
-    // transform matrix from the SurfaceTexture (which contains a vertical flip). Update tests when
-    // this is fixed.
+  static public void testLayoutMatrixDefault() {
+    final float layoutMatrix[] = getLayoutMatrix(false, 1.0f, 1.0f);
+    // Assert:
+    // u' = u.
+    // v' = v.
+    MoreAsserts.assertEquals(round(layoutMatrix), new double[]
+        {1, 0, 0, 0,
+         0, 1, 0, 0,
+         0, 0, 1, 0,
+         0, 0, 0, 1});
+  }
+
+  @SmallTest
+  static public void testLayoutMatrixMirror() {
+    final float layoutMatrix[] = getLayoutMatrix(true, 1.0f, 1.0f);
+    // Assert:
+    // u' = 1 - u.
+    // v' = v.
+    MoreAsserts.assertEquals(round(layoutMatrix), new double[]
+        {-1, 0, 0, 0,
+          0, 1, 0, 0,
+          0, 0, 1, 0,
+          1, 0, 0, 1});
+  }
+
+  @SmallTest
+  static public void testLayoutMatrixScale() {
+    // Video has aspect ratio 2, but layout is square. This will cause only the center part of the
+    // video to be visible, i.e. the u coordinate will go from 0.25 to 0.75 instead of from 0 to 1.
+    final float layoutMatrix[] = getLayoutMatrix(false, 2.0f, 1.0f);
+    // Assert:
+    // u' = 0.25 + 0.5 u.
+    // v' = v.
+    MoreAsserts.assertEquals(round(layoutMatrix), new double[]
+        { 0.5, 0, 0, 0,
+            0, 1, 0, 0,
+            0, 0, 1, 0,
+         0.25, 0, 0, 1});
+  }
+
+  @SmallTest
+  static public void testSamplingMatrixDefault() {
+    final float samplingMatrix[] = getSamplingMatrix(null, 0);
     // Assert:
     // u' = u.
     // v' = 1 - v.
-    MoreAsserts.assertEquals(round(texMatrix), new double[]
-        {1, 0, 0, 0,
+    MoreAsserts.assertEquals(round(samplingMatrix), new double[]
+        {1,  0, 0, 0,
          0, -1, 0, 0,
-         0, 0, 1, 0,
-         0, 1, 0, 1});
+         0,  0, 1, 0,
+         0,  1, 0, 1});
   }
 
   @SmallTest
-  static public void testTexMatrixMirror() {
-    final float texMatrix[] = new float[16];
-    getTextureMatrix(texMatrix, 0, true, 1.0f, 1.0f);
+  static public void testSamplingMatrixRotation90Deg() {
+    final float samplingMatrix[] = getSamplingMatrix(null, 90);
     // Assert:
     // u' = 1 - u.
     // v' = 1 - v.
-    MoreAsserts.assertEquals(round(texMatrix), new double[]
-        {-1, 0, 0, 0,
-         0, -1, 0, 0,
-         0, 0, 1, 0,
-         1, 1, 0, 1});
-  }
-
-  @SmallTest
-  static public void testTexMatrixRotation90Deg() {
-    final float texMatrix[] = new float[16];
-    getTextureMatrix(texMatrix, 90, false, 1.0f, 1.0f);
-    // Assert:
-    // u' = 1 - v.
-    // v' = 1 - u.
-    MoreAsserts.assertEquals(round(texMatrix), new double[]
-        {0, -1, 0, 0,
-         -1, 0, 0, 0,
-         0, 0, 1, 0,
-         1, 1, 0, 1});
-  }
-
-  @SmallTest
-  static public void testTexMatrixScale() {
-    final float texMatrix[] = new float[16];
-    // Video has aspect ratio 2, but layout is square. This will cause only the center part of the
-    // video to be visible, i.e. the u coordinate will go from 0.25 to 0.75 instead of from 0 to 1.
-    getTextureMatrix(texMatrix, 0, false, 2.0f, 1.0f);
-    // Assert:
-    // u' = 0.25 + 0.5 u.
-    // v' = 1 - v.
-    MoreAsserts.assertEquals(round(texMatrix), new double[]
-        {0.5, 0, 0, 0,
-         0, -1, 0, 0,
-         0, 0, 1, 0,
-         0.25, 1, 0, 1});
+    MoreAsserts.assertEquals(round(samplingMatrix), new double[]
+        { 0, -1, 0, 0,
+         -1,  0, 0, 0,
+          0,  0, 1, 0,
+          1,  1, 0, 1});
   }
 }