| /* |
| * Copyright 2014 Google Inc. All Rights Reserved. |
| * |
| * 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. |
| */ |
| |
| #include "cobalt/math/transform_2d.h" |
| |
| #include <cmath> |
| |
| namespace cobalt { |
| namespace math { |
| |
| cobalt::math::Matrix3F TranslateMatrix(float x, float y) { |
| return cobalt::math::Matrix3F::FromValues( |
| 1.0f, 0, x, |
| 0, 1.0f, y, |
| 0, 0, 1.0f); |
| } |
| |
| cobalt::math::Matrix3F ScaleMatrix(float x_scale, float y_scale) { |
| return cobalt::math::Matrix3F::FromValues( |
| x_scale, 0, 0, |
| 0, y_scale, 0, |
| 0, 0, 1.0f); |
| } |
| |
| cobalt::math::Matrix3F ScaleMatrix(float scale) { |
| return ScaleMatrix(scale, scale); |
| } |
| |
| cobalt::math::Matrix3F RotateMatrix(float counter_clockwise_angle_in_radians) { |
| float sin_theta = sin(counter_clockwise_angle_in_radians); |
| float cos_theta = cos(counter_clockwise_angle_in_radians); |
| |
| // Rotation matrix for a space where up is represented by negative y. |
| return cobalt::math::Matrix3F::FromValues( |
| cos_theta, sin_theta, 0, |
| -sin_theta, cos_theta, 0, |
| 0, 0, 1.0f); |
| } |
| |
| } // namespace math |
| } // namespace cobalt |