lyx_mirror/src/frontends/NullPainter.h
Jean-Marc Lasgouttes d222e0f48e three-stage drawing: add a nodraw stage
Normally the two stages of drawing are
1/ compute metrics of insets/rows/paragraphs/mathrow...
2/ draw the elements and cache their positions

Now the three stages are
1/ metrics
2/ nodraw: do not draw the elements, but cache their position
3/ draw the elements (and store again their position; it does not
   seems to hurt performance).

Revive the NullPainter: this replaces the setDrawingEnabled mechanism
with a painter that does nothing. The advantage is that updatePosCache
(renamed from setPosCache) does not need anymore to be invoked from
the frontend.

updatePosCache (the nodraw stage) is called at the end of
BufferView::updateMetrics.
2018-02-15 12:29:25 +01:00

110 lines
3.0 KiB
C++

// -*- C++ -*-
/**
* \file NullPainter.h
* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
* \author unknown
* \author John Levon
* \author Jean-Marc Lasgouttes
*
* Full author contact details are available in file CREDITS.
*/
#ifndef NULLPAINTER_H
#define NULLPAINTER_H
#include "Painter.h"
namespace lyx {
namespace frontend {
/**
* NullPainter - A painter instance that does nothing
*/
class NullPainter : public Painter {
public:
NullPainter() : Painter(1) {}
~NullPainter() {}
/// draw a line from point to point
void line(int, int, int, int, Color,
line_style = line_solid, int = thin_line) {}
///
void lines(int const *, int const *, int, Color,
fill_style = fill_none, line_style = line_solid,
int = thin_line) {}
///
void path(int const *, int const *, int const *, int const *,
int const *, int const *, int, Color,
fill_style = fill_none, line_style = line_solid, int = thin_line) {}
/// draw a rectangle
void rectangle(int, int, int, int, Color,
line_style = line_solid, int = thin_line) {}
/// draw a filled rectangle
void fillRectangle(int, int, int, int, Color) {}
/// draw an arc
void arc(int, int, unsigned int, unsigned int, int, int, Color) {}
/// draw a pixel
void point(int, int, Color) {}
/// draw an image from the image cache
void image(int, int, int, int, graphics::Image const &) {}
/// draw a string
void text(int, int, docstring const &, FontInfo const &) {}
/// draw a char
void text(int, int, char_type, FontInfo const &) {}
/// draw a string
void text(int, int, docstring const &, Font const &, double, double) {}
///
void text(int, int, docstring const &, Font const &,
Color, size_type, size_type, double, double) {}
/// This painter does not paint
bool isNull() const { return true; }
/// draw the underbar, strikeout, xout, uuline and uwave font attributes
void textDecoration(FontInfo const &, int, int, int) {}
/**
* Draw a string and enclose it inside a rectangle. If
* back color is specified, the background is cleared with
* the given color. If frame is specified, a thin frame is drawn
* around the text with the given color.
*/
void rectText(int, int, docstring const &,
FontInfo const &, Color, Color) {}
/// draw a string and enclose it inside a button frame
void buttonText(int, int, docstring const &,
FontInfo const &, Color, Color, int) {}
/// draw a character of a preedit string for cjk support.
int preeditText(int, int, char_type, FontInfo const &,
preedit_style) { return 0; }
/// start monochrome painting mode, i.e. map every color into [min,max]
void enterMonochromeMode(Color const &, Color const &) {}
/// leave monochrome painting mode
void leaveMonochromeMode() {}
/// draws a wavy line that can be used for underlining.
void wavyHorizontalLine(int, int, int, ColorCode) {}
};
} // namespace frontend
} // namespace lyx
#endif // NULLPAINTER_H