content: /*
   * Copyright (C) 2018 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.google.android.exoplayer2.video.spherical;
  
  import static com.google.common.truth.Truth.assertThat;
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.fail;
  
  import androidx.test.ext.junit.runners.AndroidJUnit4;
  import com.google.android.exoplayer2.C;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  
  /** Tests for {@link Projection}. */
  @RunWith(AndroidJUnit4.class)
  public class ProjectionTest {
    private static final float EPSILON = .00001f;
  
    // Default 360 sphere.
    private static final float RADIUS = 1;
    private static final int LATITUDES = 12;
    private static final int LONGITUDES = 24;
    private static final float VERTICAL_FOV_DEGREES = 180;
    private static final float HORIZONTAL_FOV_DEGREES = 360;
  
    @Test
    public void sphericalMesh() throws Exception {
      // Only the first param is important in this test.
      Projection projection =
          Projection.createEquirectangular(
              RADIUS,
              LATITUDES,
              LONGITUDES,
              VERTICAL_FOV_DEGREES,
              HORIZONTAL_FOV_DEGREES,
              C.STEREO_MODE_MONO);
  
      Projection.SubMesh subMesh = projection.leftMesh.getSubMesh(0);
      assertThat(subMesh.getVertexCount()).isGreaterThan(LATITUDES * LONGITUDES);
  
      float[] data = subMesh.vertices;
      for (int i = 0; i < data.length; ) {
        float x = data[i++];
        float y = data[i++];
        float z = data[i++];
        assertEquals(RADIUS, Math.sqrt(x * x + y * y + z * z), EPSILON);
      }
    }
  
    @Test
    public void argumentValidation() {
      checkIllegalArgumentException(0, 1, 1, 1, 1);
      checkIllegalArgumentException(1, 0, 1, 1, 1);
      checkIllegalArgumentException(1, 1, 0, 1, 1);
      checkIllegalArgumentException(1, 1, 1, 0, 1);
      checkIllegalArgumentException(1, 1, 1, 181, 1);
      checkIllegalArgumentException(1, 1, 1, 1, 0);
      checkIllegalArgumentException(1, 1, 1, 1, 361);
    }
  
    private void checkIllegalArgumentException(
        float radius,
        int latitudes,
        int longitudes,
        float verticalFovDegrees,
        float horizontalFovDegrees) {
      try {
        Projection.createEquirectangular(
            radius,
            latitudes,
            longitudes,
            verticalFovDegrees,
            horizontalFovDegrees,
            C.STEREO_MODE_MONO);
        fail();
      } catch (IllegalArgumentException e) {
        // Do nothing. Expected.
      }
    }
  }
  