Feature/time frame (#642)

* First implementation of time frames
* Add TimeFrameUnion. Only show solar system 1850-2150.
* Consider dependencies when determining whether time frame is active
* Code review fixes.

include/openspace/scene/scenegraphnode.h

@@ -48,6 +48,8 @@ class Scale;
 class Scene;
 struct UpdateData;
 struct SurfacePositionHandle;
+class TimeFrame;
+class Time;
 
 namespace documentation { struct Documentation; }
 
@@ -120,6 +122,7 @@ public:
     glm::dmat4 modelTransform() const;
     glm::dmat4 inverseModelTransform() const;
     double worldScale() const;
+    bool isTimeFrameActive(const Time& time) const;
 
     SceneGraphNode* parent() const;
     std::vector<SceneGraphNode*> children() const;
@@ -168,6 +171,8 @@ private:
         std::unique_ptr<Scale> scale;
     } _transform;
 
+    std::unique_ptr<TimeFrame> _timeFrame;
+
     // Cached transform data
     glm::dvec3 _worldPositionCached;
     glm::dmat3 _worldRotationCached;

include/openspace/scene/timeframe.h

@@ -0,0 +1,58 @@
+/*****************************************************************************************
+ *                                                                                       *
+ * OpenSpace                                                                             *
+ *                                                                                       *
+ * Copyright (c) 2014-2018                                                               *
+ *                                                                                       *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this  *
+ * software and associated documentation files (the "Software"), to deal in the Software *
+ * without restriction, including without limitation the rights to use, copy, modify,    *
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to    *
+ * permit persons to whom the Software is furnished to do so, subject to the following   *
+ * conditions:                                                                           *
+ *                                                                                       *
+ * The above copyright notice and this permission notice shall be included in all copies *
+ * or substantial portions of the Software.                                              *
+ *                                                                                       *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,   *
+ * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
+ * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT    *
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF  *
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE  *
+ * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                                         *
+ ****************************************************************************************/
+
+#ifndef __OPENSPACE_CORE___TIMEFRAME___H__
+#define __OPENSPACE_CORE___TIMEFRAME___H__
+
+#include <openspace/properties/propertyowner.h>
+
+#include <ghoul/glm.h>
+#include <memory>
+
+namespace ghoul { class Dictionary; }
+
+namespace openspace {
+
+class Time;
+
+namespace documentation { struct Documentation; }
+
+class TimeFrame : public properties::PropertyOwner {
+public:
+    static std::unique_ptr<TimeFrame> createFromDictionary(
+        const ghoul::Dictionary& dictionary);
+
+    TimeFrame();
+    virtual ~TimeFrame() = default;
+
+    virtual bool initialize();
+
+    virtual bool isActive(const Time& time) const = 0;
+
+    static documentation::Documentation Documentation();
+};
+
+}  // namespace openspace
+
+#endif // __OPENSPACE_CORE___TIMEFRAME___H__