blob: 293e20f5a459f2d5774a6e64f290fdcd2fe2d822 [file] [log] [blame]
// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/ui/lib/escher/math/rotations.h"
#include <gtest/gtest.h>
namespace {
using namespace escher;
void VerifyRotationBetweenVectors(const glm::vec3& from, const glm::vec3& to) {
// Generate two representations of a rotation that will transform |from| to
// be parallel to |to|.
glm::mat4 matrix;
glm::quat quaternion;
RotationBetweenVectors(from, to, &matrix);
RotationBetweenVectors(from, to, &quaternion);
glm::vec3 normalized_to = glm::normalize(to);
glm::vec3 transformed_from1 = quaternion * from;
glm::vec3 transformed_from2 = glm::vec3(matrix * glm::vec4(from, 1.f));
constexpr float kCloseEnough = 0.000001f;
glm::vec3 diff = normalized_to - glm::normalize(transformed_from1);
EXPECT_LT(glm::length(diff), kCloseEnough);
diff = normalized_to - glm::normalize(transformed_from2);
EXPECT_LT(glm::length(diff), kCloseEnough);
}
TEST(Rotations, BetweenParallelVectors) {
glm::vec3 v1(1.f, -99.f, 10.f);
glm::vec3 v2 = v1;
VerifyRotationBetweenVectors(v1, v2);
v2 = v1 * 0.43f;
VerifyRotationBetweenVectors(v1, v2);
v2 = v1 * -0.43f;
VerifyRotationBetweenVectors(v1, v2);
v2 = v1 * 1176.43f;
VerifyRotationBetweenVectors(v1, v2);
v2 = v1 * -1176.43f;
VerifyRotationBetweenVectors(v1, v2);
}
TEST(Rotations, BetweenPerpendicularVectors) {
glm::vec3 v1(3.f, 0.f, 0.f);
glm::vec3 v2(0.f, 5.f, 0.f);
glm::vec3 v3(0.f, 0.f, 7.f);
VerifyRotationBetweenVectors(v1, v2);
VerifyRotationBetweenVectors(v2, v1);
VerifyRotationBetweenVectors(v2, v3);
VerifyRotationBetweenVectors(v3, v2);
VerifyRotationBetweenVectors(v3, v1);
VerifyRotationBetweenVectors(v1, v3);
// Vectors will remain perpendicular after an arbitrary rotation.
glm::quat rotation;
glm::vec3 arbitrary(11.f, 19.f, 23.f);
RotationBetweenVectors(glm::vec3(0.f, 0.f, 1.f), arbitrary, &rotation);
v1 = rotation * v1;
v2 = rotation * v2;
v3 = rotation * v3;
VerifyRotationBetweenVectors(v1, v2);
VerifyRotationBetweenVectors(v2, v1);
VerifyRotationBetweenVectors(v2, v3);
VerifyRotationBetweenVectors(v3, v2);
VerifyRotationBetweenVectors(v3, v1);
VerifyRotationBetweenVectors(v1, v3);
}
} // namespace