--User changes

-Add a new dialog for editing QSS stylesheets. Allow for saving, reloading and setting styles as default.
  --Include a dark style with the installation called dark.qss.
  --Also add support for themes such as Fusion.
  --Resize some controls to better fit with the new style.
 -Add an option to specify the number of random embers generated on startup. 1 is the minimum and the default.

--Bug fixes
 -Properly enable/disable thread priority label in final render dialog in response to enable/disable of the OpenCL checkbox.
 -Remove all inline stylesheets.
 -Show xaos spinners with 6 decimal places.

--Code changes
 -Remove redundant comparisons to nullptr, use ! instead;
 -Give some controls valid names instead of the auto generated ones.
 -DoubleSpinBoxTableItemDelegate.h: Add virtual keyword to overridden functions.

Source/Fractorium/QssDialog.h

@@ -0,0 +1,141 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#pragma once
+
+#include "Fractorium.h"
+#include "FractoriumCommon.h"
+#include "QssTextEdit.h"
+#include "qcssparser.h"
+
+/// <summary>
+/// The code in this file did not originate in Fractorium.
+/// It was taken either in whole or in part from the source code
+/// of Qt Creator. Their license applies.
+/// </summary>
+
+namespace Ui
+{
+	class QssDialog;
+}
+
+/// <summary>
+/// A dialog for editing the stylesheet used in the application.
+/// This is meant to be used in the following way:
+///		On first run, no stylesheet is present/selected, so a basic style
+///		is used on startup. This style differs slightly between Windows and Linux. See BaseStyle() for details.
+///		If the user clicks Save as default or ok to exit the dialog, the text of this stylesheet will
+///		be saved to the application settings folder in the file default.qss.
+///		On all subsequent runs, the main window will detect the presence of default.qss and load it.
+///		The user can load a different stylesheet from disk, such as dark.qss which comes with the installation.
+///		They can save this back to disk (under a different name because dark.qss is made read only by the installer),
+///		however it will not become the default until they explicitly click the Save as default button or click ok.
+///		The other buttons Basic, Medium and Advanced produce an empty style sheet that gives access to various controls.
+///			Basic: Just the base style.
+///			Medium: Basic + every type of control in the application.
+///			Advanced: Medium + the name of every individual control in the application. It is not intended that the user fill
+///				out a custom style for every single control. Rather, it's to make them aware of the names of the controls in the
+///				event they want to set some custom styling for a specific control.
+///		For all practical purposes, the user will probably start with dark.qss, edit what they need and save to a new stylesheet,
+//		then set that one as the default.
+/// </summary>
+class QssDialog : public QDialog
+{
+	Q_OBJECT
+
+public:
+	explicit QssDialog(Fractorium* parent);
+	~QssDialog();
+
+	QString Text() const;
+	void SetText(const QString& t);
+	QList<QString> GetClassNames(bool includeObjectNames);
+	static bool IsStyleSheetValid(const QString& styleSheet);
+
+public slots:
+	virtual void accept() override;
+	virtual void reject() override;
+
+protected:
+	virtual void showEvent(QShowEvent* e) override;
+
+private slots:
+	void SlotTextChanged();
+	void SlotAddColor(const QString& p);
+	void SlotAddGeom(const QString& p);
+	void SlotAddBorder(const QString& p);
+	void SlotSetTheme(const QString& s);
+	void SlotAddFont();
+	void SlotApplyCss();
+
+	void LoadButton_clicked();
+	void SaveButton_clicked();
+	void SaveDefaultButton_clicked();
+	void BasicButton_clicked();
+	void MediumButton_clicked();
+	void AdvancedButton_clicked();
+
+private:
+	void InsertCssProperty(const QString &name, const QString &value);
+	void SetupFileDialog();
+	QString OpenFile();
+	QString SaveFile();
+
+	QStyle* m_Theme;
+	QStyle* m_LastTheme;
+	QString m_LastStyle;
+	QAction* m_AddColorAction;
+	QAction* m_AddGeomAction;
+	QAction* m_AddBorderAction;
+	QAction* m_AddFontAction;
+	QAction* m_AddStyleAction;
+	QSignalMapper* m_ColorActionMapper;
+	QSignalMapper* m_GeomActionMapper;
+	QSignalMapper* m_BorderActionMapper;
+	QSignalMapper* m_StyleActionMapper;
+	QHash<QString, QString> m_ColorMap;
+	QHash<QString, QString> m_GeomMap;
+	QHash<QString, QString> m_BorderMap;
+	QHash<QString, QString> m_StyleMap;
+	QTimer* m_ApplyTimer;
+	Fractorium* m_Parent;
+	QFileDialog* m_FileDialog;
+	Ui::QssDialog *ui;
+};