Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

modules/audio_processing/beamformer/array_util.h

@@ -0,0 +1,117 @@
+/*
+ *  Copyright (c) 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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_ARRAY_UTIL_H_
+#define WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_ARRAY_UTIL_H_
+
+#include <cmath>
+#include <vector>
+
+#include "webrtc/api/optional.h"
+
+namespace webrtc {
+
+// Coordinates in meters. The convention used is:
+// x: the horizontal dimension, with positive to the right from the camera's
+//    perspective.
+// y: the depth dimension, with positive forward from the camera's
+//    perspective.
+// z: the vertical dimension, with positive upwards.
+template<typename T>
+struct CartesianPoint {
+  CartesianPoint() {
+    c[0] = 0;
+    c[1] = 0;
+    c[2] = 0;
+  }
+  CartesianPoint(T x, T y, T z) {
+    c[0] = x;
+    c[1] = y;
+    c[2] = z;
+  }
+  T x() const { return c[0]; }
+  T y() const { return c[1]; }
+  T z() const { return c[2]; }
+  T c[3];
+};
+
+using Point = CartesianPoint<float>;
+
+// Calculates the direction from a to b.
+Point PairDirection(const Point& a, const Point& b);
+
+float DotProduct(const Point& a, const Point& b);
+Point CrossProduct(const Point& a, const Point& b);
+
+bool AreParallel(const Point& a, const Point& b);
+bool ArePerpendicular(const Point& a, const Point& b);
+
+// Returns the minimum distance between any two Points in the given
+// |array_geometry|.
+float GetMinimumSpacing(const std::vector<Point>& array_geometry);
+
+// If the given array geometry is linear it returns the direction without
+// normalizing.
+rtc::Optional<Point> GetDirectionIfLinear(
+    const std::vector<Point>& array_geometry);
+
+// If the given array geometry is planar it returns the normal without
+// normalizing.
+rtc::Optional<Point> GetNormalIfPlanar(
+    const std::vector<Point>& array_geometry);
+
+// Returns the normal of an array if it has one and it is in the xy-plane.
+rtc::Optional<Point> GetArrayNormalIfExists(
+    const std::vector<Point>& array_geometry);
+
+// The resulting Point will be in the xy-plane.
+Point AzimuthToPoint(float azimuth);
+
+template<typename T>
+float Distance(CartesianPoint<T> a, CartesianPoint<T> b) {
+  return std::sqrt((a.x() - b.x()) * (a.x() - b.x()) +
+                   (a.y() - b.y()) * (a.y() - b.y()) +
+                   (a.z() - b.z()) * (a.z() - b.z()));
+}
+
+// The convention used:
+// azimuth: zero is to the right from the camera's perspective, with positive
+//          angles in radians counter-clockwise.
+// elevation: zero is horizontal, with positive angles in radians upwards.
+// radius: distance from the camera in meters.
+template <typename T>
+struct SphericalPoint {
+  SphericalPoint(T azimuth, T elevation, T radius) {
+    s[0] = azimuth;
+    s[1] = elevation;
+    s[2] = radius;
+  }
+  T azimuth() const { return s[0]; }
+  T elevation() const { return s[1]; }
+  T distance() const { return s[2]; }
+  T s[3];
+};
+
+using SphericalPointf = SphericalPoint<float>;
+
+// Helper functions to transform degrees to radians and the inverse.
+template <typename T>
+T DegreesToRadians(T angle_degrees) {
+  return M_PI * angle_degrees / 180;
+}
+
+template <typename T>
+T RadiansToDegrees(T angle_radians) {
+  return 180 * angle_radians / M_PI;
+}
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_PROCESSING_BEAMFORMER_ARRAY_UTIL_H_