File indexing completed on 2024-04-21 03:57:34

 /*
     This file is part of the KDE libraries
     SPDX-FileCopyrightText: 2007 Mirko Stocker <me@misto.ch>
     SPDX-FileCopyrightText: 2003-2005 Hamish Rodda <rodda@kde.org>
     SPDX-FileCopyrightText: 2001 Christoph Cullmann <cullmann@kde.org>
     SPDX-FileCopyrightText: 2001 Joseph Wenninger <jowenn@kde.org>
     SPDX-FileCopyrightText: 1999 Jochen Wilhelmy <digisnap@cs.tu-berlin.de>
 
     SPDX-License-Identifier: LGPL-2.0-only
 */
 
 #ifndef KATE_RENDERER_H
 #define KATE_RENDERER_H
 
 #include "kateconfig.h"
 #include "ktexteditor/range.h"
 
 #include <QFlags>
 #include <QFont>
 #include <QFontMetricsF>
 #include <QTextLine>
 
 namespace KTextEditor
 {
 class DocumentPrivate;
 class ViewPrivate;
 class Attribute;
 }
 class KateRendererConfig;
 namespace Kate
 {
 class TextFolding;
 class TextLine;
 }
 
 class KateTextLayout;
 class KateLineLayout;
 typedef QExplicitlySharedDataPointer<KTextEditor::Attribute> AttributePtr;
 
 namespace KTextEditor
 {
 enum class caretStyles {
     Line,
     Block,
     Underline,
     Half,
 };
 }
 
 /**
  * Handles all of the work of rendering the text
  * (used for the views and printing)
  *
  **/
 class KateRenderer
 {
 public:
     /**
      * Style of Caret
      *
      * The caret is displayed as a vertical bar (Line), a filled box
      * (Block), a horizontal bar (Underline), or a half-height filled
      * box (Half). The default is Line.
      *
      *     Line           Block          Underline           Half
      *
      * ##     _         #########              _                _
      * ##  __| |        #####| |#           __| |            __| |
      * ## / _' |        ##/ _' |#          / _' |           / _' |
      * ##| (_| |        #| (#| |#         | (_| |         #| (#| |#
      * ## \__,_|        ##\__,_|#          \__,_|         ##\__,_|#
      * ##               #########        #########        #########
      */
 
     /**
      * Constructor
      * @param doc document to render
      * @param folding folding information
      * @param view view which is output (0 for example for rendering to print)
      */
     explicit KateRenderer(KTextEditor::DocumentPrivate *doc, Kate::TextFolding &folding, KTextEditor::ViewPrivate *view = nullptr);
 
     KateRenderer(const KateRenderer &) = delete;
     KateRenderer &operator=(const KateRenderer &) = delete;
 
     /**
      * Returns the document to which this renderer is bound
      */
     KTextEditor::DocumentPrivate *doc() const
     {
         return m_doc;
     }
 
     /**
      * Returns the folding info to which this renderer is bound
      * @return folding info
      */
     Kate::TextFolding &folding() const
     {
         return m_folding;
     }
 
     /**
      * Returns the view to which this renderer is bound
      */
     KTextEditor::ViewPrivate *view() const
     {
         return m_view;
     }
 
     /**
      * update the highlighting attributes
      * (for example after an hl change or after hl config changed)
      */
     void updateAttributes();
 
     /**
      * Determine whether the caret (text cursor) will be drawn.
      * @return should it be drawn?
      */
     inline bool drawCaret() const
     {
         return m_drawCaret;
     }
 
     /**
      * Set whether the caret (text cursor) will be drawn.
      * @param drawCaret should caret be drawn?
      */
     void setDrawCaret(bool drawCaret);
 
     /**
      * The style of the caret (text cursor) to be painted.
      * @return caretStyle
      */
     inline KTextEditor::caretStyles caretStyle() const
     {
         return m_caretStyle;
     }
 
     /**
      * Set the style of caret to be painted.
      * @param style style to set
      */
     void setCaretStyle(KTextEditor::caretStyles style);
 
     /**
      * Set a \a brush with which to override drawing of the caret.  Set to QColor() to clear.
      */
     void setCaretOverrideColor(const QColor &color);
 
     /**
      * @returns whether tabs should be shown (ie. a small mark
      * drawn to identify a tab)
      * @return tabs should be shown
      */
     inline bool showTabs() const
     {
         return m_showTabs;
     }
 
     /**
      * Set whether a mark should be painted to help identifying tabs.
      * @param showTabs show the tabs?
      */
     void setShowTabs(bool showTabs);
 
     /**
      * Set which spaces should be rendered
      */
     void setShowSpaces(KateDocumentConfig::WhitespaceRendering showSpaces);
 
     /**
      * @returns whether which spaces should be rendered
      */
     inline KateDocumentConfig::WhitespaceRendering showSpaces() const
     {
         return m_showSpaces;
     }
 
     /**
      * Update marker size shown.
      */
     void updateMarkerSize();
 
     /**
      * @returns whether non-printable spaces should be shown
      */
     inline bool showNonPrintableSpaces() const
     {
         return m_showNonPrintableSpaces;
     }
 
     /**
      * Set whether box should be drawn around non-printable spaces
      */
     void setShowNonPrintableSpaces(const bool showNonPrintableSpaces);
 
     /**
      * Sets the width of the tab. Helps performance.
      * @param tabWidth new tab width
      */
     void setTabWidth(int tabWidth);
 
     /**
      * @returns whether indent lines should be shown
      * @return indent lines should be shown
      */
     bool showIndentLines() const;
 
     /**
      * Set whether a guide should be painted to help identifying indent lines.
      * @param showLines show the indent lines?
      */
     void setShowIndentLines(bool showLines);
 
     /**
      * Sets the width of the tab. Helps performance.
      * @param indentWidth new indent width
      */
     void setIndentWidth(int indentWidth);
 
     /**
      * Show the view's selection?
      * @return show sels?
      */
     inline bool showSelections() const
     {
         return m_showSelections;
     }
 
     /**
      * Set whether the view's selections should be shown.
      * The default is true.
      * @param showSelections show the selections?
      */
     void setShowSelections(bool showSelections);
 
     /**
      * Change to a different font (soon to be font set?)
      */
     void increaseFontSizes(qreal step = 1.0) const;
     void decreaseFontSizes(qreal step = 1.0) const;
     void resetFontSizes() const;
 
     /**
      * Access currently used font.
      * @return current font
      */
     const QFont &currentFont() const
     {
         return m_font;
     }
 
     /**
      * Access currently used font metrics.
      * @return current font metrics
      */
     const QFontMetricsF &currentFontMetrics() const
     {
         return m_fontMetrics;
     }
 
     /**
      * @return whether the renderer is configured to paint in a
      * printer-friendly fashion.
      */
     bool isPrinterFriendly() const;
 
     /**
      * Configure this renderer to paint in a printer-friendly fashion.
      *
      * Sets the other options appropriately if true.
      */
     void setPrinterFriendly(bool printerFriendly);
 
     /**
      * Text width & height calculation functions...
      */
     void layoutLine(KateLineLayout *line, int maxwidth = -1, bool cacheLayout = false) const;
 
     /**
      * This is a smaller QString::isRightToLeft(). It's also marked as internal to kate
      * instead of internal to Qt, so we can modify. This method searches for the first
      * strong character in the paragraph and then returns its direction. In case of a
      * line without any strong characters, the direction is forced to be LTR.
      *
      * Back in KDE 4.1 this method counted chars, which lead to unwanted side effects.
      * (see https://bugs.kde.org/show_bug.cgi?id=178594). As this function is internal
      * the way it work will probably change between releases. Be warned!
      */
     static bool isLineRightToLeft(QStringView str);
 
     /**
      * The ultimate decoration creation function.
      *
      * \param selectionsOnly return decorations for selections and/or dynamic highlighting.
      */
     QList<QTextLayout::FormatRange> decorationsForLine(const Kate::TextLine &textLine, int line, bool selectionsOnly = false) const;
 
     // Width calculators
     qreal spaceWidth() const;
 
     /**
      * Returns the x position of cursor \p col on the line \p range.
      */
     int cursorToX(const KateTextLayout &range, int col, bool returnPastLine = false) const;
     /// \overload
     int cursorToX(const KateTextLayout &range, const KTextEditor::Cursor pos, bool returnPastLine = false) const;
 
     /**
      * Returns the real cursor which is occupied by the specified x value, or that closest to it.
      * If \p returnPastLine is true, the column will be extrapolated out with the assumption
      * that the extra characters are spaces.
      */
     KTextEditor::Cursor xToCursor(const KateTextLayout &range, int x, bool returnPastLine = false) const;
 
     // Font height
     uint fontHeight() const;
 
     // Line height
     int lineHeight() const;
 
     // Document height
     uint documentHeight() const;
 
     // Selection boundaries
     bool getSelectionBounds(int line, int lineLength, int &start, int &end) const;
 
     /**
      * Flags to customize the paintTextLine function behavior
      */
     enum PaintTextLineFlag {
         /**
          * Skip drawing the dashed underline at the start of a folded block of text?
          */
         SkipDrawFirstInvisibleLineUnderlined = 0x1,
         /**
          * Skip drawing the line selection
          * This is useful when we are drawing the draggable pixmap for drag event
          */
         SkipDrawLineSelection = 0x2
     };
     Q_DECLARE_FLAGS(PaintTextLineFlags, PaintTextLineFlag)
 
     /**
      * This is the ultimate function to perform painting of a text line.
      *
      * The text line is painted from the upper limit of (0,0).  To move that,
      * apply a transform to your painter.
      *
      * @param paint           painter to use
      * @param range           layout to use in painting this line
      * @param textClipRect    clip rect for text to not paint lines outside the visible area.
      * @param xStart          starting width in pixels.
      * @param xEnd            ending width in pixels.
      * @param cursor          position of the caret, if placed on the current line.
      * @param flags           flags for customizing the drawing of the line
      */
     void paintTextLine(QPainter &paint,
                        KateLineLayout *range,
                        int xStart,
                        int xEnd,
                        const QRectF &textClipRect = QRectF(),
                        const KTextEditor::Cursor *cursor = nullptr,
                        PaintTextLineFlags flags = PaintTextLineFlags());
 
     /**
      * Paint the background of a line
      *
      * Split off from the main @ref paintTextLine method to make it smaller. As it's being
      * called only once per line it shouldn't noticably affect performance and it
      * helps readability a LOT.
      *
      * @param paint           painter to use
      * @param layout          layout to use in painting this line
      * @param currentViewLine if one of the view lines is the current line, set
      *                        this to the index; otherwise -1.
      * @param xStart          starting width in pixels.
      * @param xEnd            ending width in pixels.
      */
     void paintTextLineBackground(QPainter &paint, KateLineLayout *layout, int currentViewLine, int xStart, int xEnd);
 
     void paintTextBackground(QPainter &paint, KateLineLayout *layout, const QList<QTextLayout::FormatRange> &selRanges, const QBrush &br) const;
 
     /**
      * This takes an in index, and returns all the attributes for it.
      * For example, if you have a ktextline, and want the KTextEditor::Attribute
      * for a given position, do:
      *
      *   attribute(myktextline->attribute(position));
      */
     const AttributePtr &attribute(uint pos) const;
     AttributePtr specificAttribute(int context) const;
 
     /**
      * Paints a range of text into @a d. This function is mainly used to paint the pixmap
      * when dragging text.
      *
      * Please note that this will not paint the selection background but only the text.
      *
      * @param d                 the paint device
      * @param startLine         start line
      * @param xStart            start pos on @a startLine in pixels
      * @param endLine           end line
      * @param xEnd              end pos on @a endLine in pixels
      * @param scale             the amount of scaling to apply. Default is 1.0, negative values are not supported
      */
     void paintSelection(QPaintDevice *d, int startLine, int xStart, int endLine, int xEnd, qreal scale = 1.0);
 
 private:
     /**
      * Paint a trailing space on position (x, y).
      */
     void paintSpaces(QPainter &paint, const QPointF *points, const int count) const;
     /**
      * Paint a tab stop marker on position (x, y).
      */
     void paintTabstop(QPainter &paint, qreal x, qreal y) const;
 
     /**
      * Paint a non-breaking space marker on position (x, y).
      */
     void paintNonBreakSpace(QPainter &paint, qreal x, qreal y) const;
 
     /**
      * Paint non printable spaces bounding box
      */
     void paintNonPrintableSpaces(QPainter &paint, qreal x, qreal y, const QChar &chr);
 
     /** Paint a SciTE-like indent marker. */
     void paintIndentMarker(QPainter &paint, uint x, int line);
 
     static void assignSelectionBrushesFromAttribute(QTextLayout::FormatRange &target, const KTextEditor::Attribute &attribute);
 
     void paintCaret(KTextEditor::Cursor cursor, KateLineLayout *range, QPainter &paint, int xStart, int xEnd);
 
     // update font height
     void updateFontHeight();
 
     bool hasCustomLineHeight() const;
 
     KTextEditor::DocumentPrivate *const m_doc;
     Kate::TextFolding &m_folding;
     KTextEditor::ViewPrivate *const m_view;
 
     // cache of config values
     int m_tabWidth;
     int m_indentWidth;
     int m_fontHeight;
     float m_fontAscent;
 
     // if we are at bracket, this will have the X for the opener
     int m_currentBracketX = -1;
 
     // The bracket range, if we are at a bracket
     KTextEditor::Range m_currentBracketRange = KTextEditor::Range::invalid();
 
     // some internal flags
     KTextEditor::caretStyles m_caretStyle;
     bool m_drawCaret;
     bool m_showSelections;
     bool m_showTabs;
     KateDocumentConfig::WhitespaceRendering m_showSpaces = KateDocumentConfig::None;
     float m_markerSize;
     bool m_showNonPrintableSpaces;
     bool m_printerFriendly;
     QColor m_caretOverrideColor;
 
     QList<AttributePtr> m_attributes;
 
     /**
      * Configuration
      */
 public:
     void updateConfig();
 
     inline KateRendererConfig *config() const
     {
         return m_config.get();
     }
 
 private:
     std::unique_ptr<KateRendererConfig> const m_config;
 
     /**
      * cached font, was perhaps adjusted for current DPIs
      */
     QFont m_font;
 
     /**
      * cached font metrics
      */
     QFontMetricsF m_fontMetrics;
 };
 
 #endif