task: massively simplified task system

Made various changes and fixes to the task system:

- Tasks are built around QtConcurrent rather than QThread. Reduces
  code complexity significantly.
- Task error reporting is now streamlined in both TaskManager and
  TaskDialog.
- Moved ProjectImport/Save/LoadManager to the app/task folder

app/task/export/CMakeLists.txt

@@ -0,0 +1,24 @@
+# Olive - Non-Linear Video Editor
+# Copyright (C) 2019 Olive Team
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+set(OLIVE_SOURCES
+  ${OLIVE_SOURCES}
+  task/export/export.h
+  task/export/export.cpp
+  task/export/exportparams.h
+  task/export/exportparams.cpp
+  PARENT_SCOPE
+)

app/task/export/export.cpp

@@ -0,0 +1,39 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2019 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#include "export.h"
+
+OLIVE_NAMESPACE_ENTER
+
+ExportTask::ExportTask(ViewerOutput* viewer_node,
+                       ColorManager* color_manager,
+                       const ExportParams& params) :
+  RenderTask(viewer_node),
+  color_manager_(color_manager),
+  params_(params)
+{
+}
+
+bool ExportTask::Run()
+{
+  return true;
+}
+
+OLIVE_NAMESPACE_EXIT

app/task/export/export.h

@@ -0,0 +1,50 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2019 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#ifndef EXPORTTASK_H
+#define EXPORTTASK_H
+
+#include "exportparams.h"
+#include "node/output/viewer/viewer.h"
+#include "render/colorprocessor.h"
+#include "task/render/render.h"
+#include "task/task.h"
+
+OLIVE_NAMESPACE_ENTER
+
+class ExportTask : public RenderTask
+{
+  Q_OBJECT
+public:
+  ExportTask(ViewerOutput *viewer_node, ColorManager *color_manager, const ExportParams &params);
+
+public slots:
+  virtual bool Run() override;
+
+private:
+  ColorManager* color_manager_;
+
+  ExportParams params_;
+
+};
+
+OLIVE_NAMESPACE_EXIT
+
+#endif // EXPORTTASK_H

app/task/export/exportparams.cpp

@@ -0,0 +1,103 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2019 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#include "exportparams.h"
+
+OLIVE_NAMESPACE_ENTER
+
+ExportParams::ExportParams() :
+  video_scaling_method_(kStretch),
+  has_custom_range_(false)
+{
+}
+
+const QString &ExportParams::encoder() const
+{
+  return encoder_id_;
+}
+
+void ExportParams::set_encoder(const QString &id)
+{
+  encoder_id_ = id;
+}
+
+bool ExportParams::has_custom_range() const
+{
+  return has_custom_range_;
+}
+
+const TimeRange &ExportParams::custom_range() const
+{
+  return custom_range_;
+}
+
+void ExportParams::set_custom_range(const TimeRange &custom_range)
+{
+  has_custom_range_ = true;
+  custom_range_ = custom_range;
+}
+
+const ExportParams::VideoScalingMethod &ExportParams::video_scaling_method() const
+{
+  return video_scaling_method_;
+}
+
+void ExportParams::set_video_scaling_method(const ExportParams::VideoScalingMethod &video_scaling_method)
+{
+  video_scaling_method_ = video_scaling_method;
+}
+
+const ColorTransform &ExportParams::color_transform() const
+{
+  return color_transform_;
+}
+
+void ExportParams::set_color_transform(const ColorTransform &color_transform)
+{
+  color_transform_ = color_transform;
+}
+
+QMatrix4x4 ExportParams::GenerateMatrix(ExportParams::VideoScalingMethod method,
+                                        int source_width, int source_height,
+                                        int dest_width, int dest_height)
+{
+  QMatrix4x4 preview_matrix;
+
+  if (method == ExportParams::kStretch) {
+    return preview_matrix;
+  }
+
+  float export_ar = static_cast<float>(dest_width) / static_cast<float>(dest_height);
+  float source_ar = static_cast<float>(source_width) / static_cast<float>(source_height);
+
+  if (qFuzzyCompare(export_ar, source_ar)) {
+    return preview_matrix;
+  }
+
+  if ((export_ar > source_ar) == (method == ExportParams::kFit)) {
+    preview_matrix.scale(source_ar / export_ar, 1.0F);
+  } else {
+    preview_matrix.scale(1.0F, export_ar / source_ar);
+  }
+
+  return preview_matrix;
+}
+
+OLIVE_NAMESPACE_EXIT

app/task/export/exportparams.h

@@ -0,0 +1,73 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2019 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#ifndef EXPORTPARAMS_H
+#define EXPORTPARAMS_H
+
+#include <QMatrix4x4>
+
+#include "codec/encoder.h"
+#include "node/output/viewer/viewer.h"
+#include "render/colortransform.h"
+
+OLIVE_NAMESPACE_ENTER
+
+class ExportParams : public EncodingParams {
+public:
+  enum VideoScalingMethod {
+    kFit,
+    kStretch,
+    kCrop
+  };
+
+  ExportParams();
+
+  const QString& encoder() const;
+  void set_encoder(const QString& id);
+
+  bool has_custom_range() const;
+  const TimeRange& custom_range() const;
+  void set_custom_range(const TimeRange& custom_range);
+
+  const VideoScalingMethod& video_scaling_method() const;
+  void set_video_scaling_method(const VideoScalingMethod& video_scaling_method);
+
+  const ColorTransform& color_transform() const;
+  void set_color_transform(const ColorTransform& color_transform);
+
+  static QMatrix4x4 GenerateMatrix(ExportParams::VideoScalingMethod method,
+                                   int source_width, int source_height,
+                                   int dest_width, int dest_height);
+
+private:
+  QString encoder_id_;
+
+  VideoScalingMethod video_scaling_method_;
+
+  bool has_custom_range_;
+  TimeRange custom_range_;
+
+  ColorTransform color_transform_;
+
+};
+
+OLIVE_NAMESPACE_EXIT
+
+#endif // EXPORTPARAMS_H