4 * This file is part of LyX, the document processor.
5 * Licence details can be found in the file COPYING.
10 * Full author contact details are available in file CREDITS.
16 #include "support/strfwd.h"
22 namespace graphics { class Image; }
27 * Painter - A painter class to encapsulate all graphics parameters and operations
29 * Every graphics operation in LyX should be made by this class. The
30 * painter is used for drawing on the WorkArea, and is passed around
31 * during draw operations.
33 * It hides low level windows system parameters so insets and other
34 * clients don't have to worry about them and we can control graphics and
35 * GUI toolkit dependent drawing functions inside this single class.
37 * The intention for a toolkit is that it uses these methods to paint
38 * onto a backing pixmap. Only when expose events arrive via the event
39 * queue (perhaps generated via Screen::expose), does the copy onto
40 * the actual WorkArea widget take place. Paints are wrapped in (possibly
41 * recursive) calls to start() and end() to facilitate the backing pixmap
44 * Note that the methods return *this for convenience.
46 * Caution: All char_type and docstring arguments of the text drawing
47 * methods of this class are no UCS4 chars or strings if the font is a
48 * symbol font. They simply denote the code points of the font instead.
49 * You have to keep this in mind when you implement the methods in a
50 * frontend. You must not pass these parameters to a unicode conversion
51 * function in particular.
55 Painter() : drawing_enabled_(true) {}
58 static const float thin_line;
60 /// possible line styles
62 line_solid, //< solid line
63 line_onoffdash //< dashes with spaces
66 /// possible character styles of preedit string.
67 /// This is used for CJK input method support.
69 preedit_default, //< when unselecting, no cursor and dashed underline.
70 preedit_selecting, //< when selecting.
71 preedit_cursor //< with cursor.
76 /// draw a line from point to point
77 virtual void line(int x1, int y1, int x2, int y2, Color,
78 line_style = line_solid, float line_width = thin_line) = 0;
81 * lines - draw a set of lines
82 * @param xp array of points' x co-ords
83 * @param yp array of points' y co-ords
84 * @param np size of the points array
86 virtual void lines(int const * xp, int const * yp, int np, Color,
87 line_style = line_solid, float line_width = thin_line) = 0;
90 virtual void rectangle(int x, int y, int w, int h, Color,
91 line_style = line_solid, float line_width = thin_line) = 0;
93 /// draw a filled rectangle
94 virtual void fillRectangle(int x, int y, int w, int h, Color) = 0;
97 virtual void arc(int x, int y, unsigned int w, unsigned int h,
98 int a1, int a2, Color) = 0;
101 virtual void point(int x, int y, Color) = 0;
103 /// draw a filled rectangle with the shape of a 3D button
104 virtual void button(int x, int y, int w, int h, bool mouseHover) = 0;
106 /// draw an image from the image cache
107 virtual void image(int x, int y, int w, int h,
108 graphics::Image const & image) = 0;
110 /// draw a string at position x, y (y is the baseline)
112 * \return the width of the drawn text.
114 virtual int text(int x, int y, docstring const & str, FontInfo const & f) = 0;
116 void setDrawingEnabled(bool drawing_enabled)
117 { drawing_enabled_ = drawing_enabled; }
119 /// Indicate wether real screen drawing shall be done or not.
120 bool isDrawingEnabled() const { return drawing_enabled_; }
122 /// draw a char at position x, y (y is the baseline)
124 * \return the width of the drawn text.
126 virtual int text(int x, int y, char_type c, FontInfo const & f) = 0;
128 /// draw the underbar, strikeout, uuline and uwave font attributes
129 virtual void textDecoration(FontInfo const & f, int x, int y, int width) = 0;
132 * Draw a string and enclose it inside a rectangle. If
133 * back color is specified, the background is cleared with
134 * the given color. If frame is specified, a thin frame is drawn
135 * around the text with the given color.
137 virtual void rectText(int x, int baseline, docstring const & str,
138 FontInfo const & font, Color back, Color frame) = 0;
140 /// draw a string and enclose it inside a button frame
141 virtual void buttonText(int x, int baseline, docstring const & s,
142 FontInfo const & font, bool mouseHover) = 0;
144 /// draw a character of a preedit string for cjk support.
145 virtual int preeditText(int x, int y,
146 char_type c, FontInfo const & f, preedit_style style) = 0;
148 /// start monochrome painting mode, i.e. map every color into [min,max]
149 virtual void enterMonochromeMode(Color const & min,
150 Color const & max) = 0;
151 /// leave monochrome painting mode
152 virtual void leaveMonochromeMode() = 0;
153 /// draws a wavy line that can be used for underlining.
154 virtual void wavyHorizontalLine(int x, int y, int width, ColorCode col) = 0;
157 bool drawing_enabled_;
160 } // namespace frontend