/*
* 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 "mathfu/matrix_4x4.h"
#include "mathfu/utilities.h"

#include <math.h>
#include <stdlib.h>
#include <stdio.h>

#include "benchmark_common.h"

// Number of elements to iterate over
static const size_t kMatrixSize = 1000;
// Number of iterations of each operation.
static const size_t kIterations = 50;

using mathfu::Matrix;
using mathfu::Random;

#define MATRIX_DIMENSIONS 4

typedef float T;

typedef Matrix<T, MATRIX_DIMENSIONS> TestMatrix;

// This test creates a number of matrices and performs some mathematical
// operations on them in order to measure expected performance of matrix
// operations.
int main(int argc, char** argv) {
  (void)argc;
  (void)argv;
  // Create an array of matrices containing random values.
  TestMatrix * const matrices = new TestMatrix[kMatrixSize];
  TestMatrix mul = TestMatrix::Identity();
  for (size_t i = 0; i < kMatrixSize; ++i) {
    TestMatrix mat;
    for (size_t j = 0; j < MATRIX_DIMENSIONS; ++j) {
      mat[static_cast<int>(j)] = Random<T>();
    }
    matrices[i] = mat;
  }
  // Start matrix benchmark, running a number of loops for more accurate
  // numbers.
  printf("Running matrix benchmark (%s)...\n", MATHFU_BUILD_OPTIONS_STRING);
  Timer timer;
  PERFTEST_2D_VECTOR_LOOP(kIterations, kMatrixSize) mul += matrices[j];
  PERFTEST_2D_VECTOR_LOOP(kIterations, kMatrixSize) mul *= matrices[j];

#if MATRIX_DIMENSIONS == 4
  PERFTEST_2D_VECTOR_LOOP(kIterations, kMatrixSize) {
    mathfu::Vector<T, MATRIX_DIMENSIONS> tmp =
      matrices[j] * mathfu::Vector<T, MATRIX_DIMENSIONS>(
          matrices[i](0, 0), matrices[i](1, 0),
          matrices[i](2, 0), matrices[i](3, 0));
    mul -= TestMatrix::OuterProduct(tmp, tmp);
  }
#endif  // MATRIX_DIMENSIONS == 4
  PERFTEST_2D_VECTOR_LOOP(kIterations, kMatrixSize) {
    mul += matrices[j] * Random<T>();
  }
  // End matrix performance code
  double elapsed = timer.GetElapsedSeconds();
  printf("Took %f seconds\n", elapsed);
  delete [] matrices;
  return 0;
}