completed color management implementation

This commit adds the background functionality of the render cache invalidating
whenever a footage's color space is changed. This includes when the project's
configuration is changed as well.

app/project/item/footage/imagestream.cpp

@@ -20,6 +20,8 @@
 
 #include "imagestream.h"
 
+#include "footage.h"
+#include "project/project.h"
 #include "render/colormanager.h"
 
 ImageStream::ImageStream() :
@@ -69,7 +71,11 @@ void ImageStream::set_premultiplied_alpha(bool e)
 
 const QString &ImageStream::colorspace()
 {
-  return colorspace_;
+  if (colorspace_.isEmpty()) {
+    return footage()->project()->default_input_colorspace();
+  } else {
+    return colorspace_;
+  }
 }
 
 void ImageStream::set_colorspace(const QString &color)
@@ -81,6 +87,15 @@ void ImageStream::set_colorspace(const QString &color)
 
 void ImageStream::ColorConfigChangedSlot()
 {
-  // FIXME: Update colorspace correctly
-  colorspace_.clear();
+  // Check if this colorspace is in the new config
+  if (!colorspace_.isEmpty()) {
+    QStringList colorspaces = ColorManager::ListAvailableInputColorspaces(OCIO::GetCurrentConfig());
+    if (!colorspaces.contains(colorspace_)) {
+      // Set to empty if not
+      colorspace_.clear();
+    }
+  }
+
+  // Either way, the color calculation has likely changed so we signal here
+  emit ColorSpaceChanged();
 }

app/project/item/item.cpp

@@ -21,7 +21,8 @@
 #include "item.h"
 
 Item::Item() :
-  parent_(nullptr)
+  parent_(nullptr),
+  project_(nullptr)
 {
 }
 
@@ -127,6 +128,18 @@ const Item *Item::root() const
   return item;
 }
 
+Project *Item::project() const
+{
+  const Item* root_item = root();
+
+  return root_item->project_;
+}
+
+void Item::set_project(Project *project)
+{
+  project_ = project;
+}
+
 bool Item::CanHaveChildren() const
 {
   return false;

app/project/item/item.h

@@ -29,6 +29,8 @@
 
 #include "common/threadedobject.h"
 
+class Project;
+
 class Item;
 using ItemPtr = std::shared_ptr<Item>;
 
@@ -101,6 +103,9 @@ public:
   Item *parent() const;
   const Item* root() const;
 
+  Project* project() const;
+  void set_project(Project* project);
+
   virtual bool CanHaveChildren() const;
 
   bool ChildExistsWithName(const QString& name);
@@ -112,6 +117,8 @@ private:
 
   Item* parent_;
 
+  Project* project_;
+
   QString name_;
 
   QString tooltip_;

app/project/project.cpp

@@ -23,6 +23,7 @@
 Project::Project()
 {
   name_ = tr("(untitled)");
+  root_.set_project(this);
 }
 
 Folder *Project::root()