Rename plugins to external

applications/external/airmouse/tracking/util/matrix_4x4.cc

@@ -0,0 +1,87 @@
+/*
+ * Copyright 2019 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 "matrix_4x4.h"
+
+#include <algorithm>
+#include <cmath>
+#include <cstring>
+
+namespace cardboard {
+
+Matrix4x4 Matrix4x4::Identity()
+{
+    Matrix4x4 ret;
+    for (int j = 0; j < 4; ++j) {
+        for (int i = 0; i < 4; ++i) {
+            ret.m[j][i] = (i == j) ? 1 : 0;
+        }
+    }
+
+    return ret;
+}
+
+Matrix4x4 Matrix4x4::Zeros()
+{
+    Matrix4x4 ret;
+    for (int j = 0; j < 4; ++j) {
+        for (int i = 0; i < 4; ++i) {
+            ret.m[j][i] = 0;
+        }
+    }
+
+    return ret;
+}
+
+Matrix4x4 Matrix4x4::Translation(float x, float y, float z)
+{
+    Matrix4x4 ret = Matrix4x4::Identity();
+    ret.m[3][0] = x;
+    ret.m[3][1] = y;
+    ret.m[3][2] = z;
+
+    return ret;
+}
+
+Matrix4x4 Matrix4x4::Perspective(const std::array<float, 4>& fov, float zNear, float zFar)
+{
+    Matrix4x4 ret = Matrix4x4::Zeros();
+
+    const float xLeft = -std::tan(fov[0] * M_PI / 180.0f) * zNear;
+    const float xRight = std::tan(fov[1] * M_PI / 180.0f) * zNear;
+    const float yBottom = -std::tan(fov[2] * M_PI / 180.0f) * zNear;
+    const float yTop = std::tan(fov[3] * M_PI / 180.0f) * zNear;
+
+    const float X = (2 * zNear) / (xRight - xLeft);
+    const float Y = (2 * zNear) / (yTop - yBottom);
+    const float A = (xRight + xLeft) / (xRight - xLeft);
+    const float B = (yTop + yBottom) / (yTop - yBottom);
+    const float C = (zNear + zFar) / (zNear - zFar);
+    const float D = (2 * zNear * zFar) / (zNear - zFar);
+
+    ret.m[0][0] = X;
+    ret.m[2][0] = A;
+    ret.m[1][1] = Y;
+    ret.m[2][1] = B;
+    ret.m[2][2] = C;
+    ret.m[3][2] = D;
+    ret.m[2][3] = -1;
+
+    return ret;
+}
+
+void Matrix4x4::ToArray(float* array) const { std::memcpy(array, &m[0][0], 16 * sizeof(float)); }
+
+} // namespace cardboard