screenshot_pass.cpp

//------------------------------------------------------------------------------
// Project Phoenix
//
// Copyright (c) 2017-2018 RWTH Aachen University, Germany,
// Virtual Reality & Immersive Visualization Group.
//------------------------------------------------------------------------------
//                                 License
//
// Licensed under the 3-Clause BSD License (the "License");
// you may not use this file except in compliance with the License.
// See the file LICENSE for the full text.
// You may obtain a copy of the License at
//
//     https://opensource.org/licenses/BSD-3-Clause
//
// 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 "screenshot_pass.hpp"
#include "phx/core/logger.hpp"
#include "phx/resources/types/image.hpp"

#include <fstream>

namespace phx {

// Copied from Stackoverflow
inline bool file_exists(const std::string& name) {
  std::ifstream f(name.c_str());
  return f.good();
}

ScreenshotPass::ScreenshotPass(RenderTarget* render_target)
    : render_target_(render_target) {}

ScreenshotPass::~ScreenshotPass() { free(data_storage_); }

void ScreenshotPass::Initialize() {
  dims_ = render_target_->GetDimensions();
  data_storage_ = malloc(dims_.x * dims_.y * 4);
}

void ScreenshotPass::Execute() {
  if (!screenshot_next_frame) return;

  // Get Pixels into Memory
  render_target_->bind();
  glReadPixels(0, 0, dims_.x, dims_.y, GL_RGB, GL_UNSIGNED_BYTE, data_storage_);
  render_target_->unbind();

  // Save to disk
  auto image = new phx::Image(data_storage_, {dims_.x, dims_.y}, 24);
  auto name = FindNextFileName("Screenshot_") + ".png";
  if (image->Save(name)) {
    phx::info(("Saved " + name).c_str());
  } else {
    phx::warn(("Could not save " + name).c_str());
  }
  delete image;

  // Reset
  screenshot_next_frame = false;
}

void ScreenshotPass::Screenshot() { screenshot_next_frame = true; }

std::string ScreenshotPass::FindNextFileName(const std::string name) {
  unsigned int i = 0;
  while (file_exists(name + std::to_string(i) + ".png")) {
    i++;
  }
  return name + std::to_string(i);
}
}  // namespace phx