/* $Id$ */
/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see .
*/
/** @file gfx_layout.h Functions related to laying out the texts. */
#ifndef GFX_LAYOUT_H
#define GFX_LAYOUT_H
#include "fontcache.h"
#include "gfx_func.h"
#include "core/smallmap_type.hpp"
#ifdef WITH_ICU
#include "layout/ParagraphLayout.h"
#define ICU_FONTINSTANCE : public LEFontInstance
#else /* WITH_ICU */
#define ICU_FONTINSTANCE
#endif /* WITH_ICU */
/**
* Text drawing parameters, which can change while drawing a line, but are kept between multiple parts
* of the same text, e.g. on line breaks.
*/
struct FontState {
FontSize fontsize; ///< Current font size.
TextColour cur_colour; ///< Current text colour.
TextColour prev_colour; ///< Text colour from before the last colour switch.
FontState(TextColour colour, FontSize fontsize) : fontsize(fontsize), cur_colour(colour), prev_colour(colour) {}
/**
* Switch to new colour \a c.
* @param c New colour to use.
*/
inline void SetColour(TextColour c)
{
assert(c >= TC_BLUE && c <= TC_BLACK);
this->prev_colour = this->cur_colour;
this->cur_colour = c;
}
/** Switch to previous colour. */
inline void SetPreviousColour()
{
Swap(this->cur_colour, this->prev_colour);
}
/**
* Switch to using a new font \a f.
* @param f New font to use.
*/
inline void SetFontSize(FontSize f)
{
this->fontsize = f;
}
};
/**
* Container with information about a font.
*/
class Font ICU_FONTINSTANCE {
public:
FontCache *fc; ///< The font we are using.
TextColour colour; ///< The colour this font has to be.
Font(FontSize size, TextColour colour);
#ifdef WITH_ICU
/* Implementation details of LEFontInstance */
le_int32 getUnitsPerEM() const;
le_int32 getAscent() const;
le_int32 getDescent() const;
le_int32 getLeading() const;
float getXPixelsPerEm() const;
float getYPixelsPerEm() const;
float getScaleFactorX() const;
float getScaleFactorY() const;
const void *getFontTable(LETag tableTag) const;
const void *getFontTable(LETag tableTag, size_t &length) const;
LEGlyphID mapCharToGlyph(LEUnicode32 ch) const;
void getGlyphAdvance(LEGlyphID glyph, LEPoint &advance) const;
le_bool getGlyphPoint(LEGlyphID glyph, le_int32 pointNumber, LEPoint &point) const;
#endif /* WITH_ICU */
};
/** Mapping from index to font. */
typedef SmallMap FontMap;
#ifndef WITH_ICU
/**
* Class handling the splitting of a paragraph of text into lines and
* visual runs.
*
* One constructs this class with the text that needs to be split into
* lines. Then nextLine is called with the maximum width until NULL is
* returned. Each nextLine call creates VisualRuns which contain the
* length of text that are to be drawn with the same font. In other
* words, the result of this class is a list of sub strings with their
* font. The sub strings are then already fully laid out, and only
* need actual drawing.
*
* The positions in a visual run are sequential pairs of X,Y of the
* begin of each of the glyphs plus an extra pair to mark the end.
*
* @note This variant does not handle left-to-right properly. This
* is supported in the one ParagraphLayout coming from ICU.
* @note Does not conform to function naming style as it provides a
* fallback for the ICU class.
*/
class ParagraphLayout {
public:
/** Visual run contains data about the bit of text with the same font. */
class VisualRun {
Font *font; ///< The font used to layout these.
GlyphID *glyphs; ///< The glyphs we're drawing.
float *positions; ///< The positions of the glyphs.
int glyph_count; ///< The number of glyphs.
public:
VisualRun(Font *font, const WChar *chars, int glyph_count, int x);
~VisualRun();
Font *getFont() const;
int getGlyphCount() const;
const GlyphID *getGlyphs() const;
float *getPositions() const;
int getLeading() const;
};
/** A single line worth of VisualRuns. */
class Line : public AutoDeleteSmallVector {
public:
int getLeading() const;
int getWidth() const;
int countRuns() const;
VisualRun *getVisualRun(int run) const;
};
const WChar *buffer_begin; ///< Begin of the buffer.
WChar *buffer; ///< The current location in the buffer.
FontMap &runs; ///< The fonts we have to use for this paragraph.
ParagraphLayout(WChar *buffer, int length, FontMap &runs);
Line *nextLine(int max_width);
};
#endif /* !WITH_ICU */
/**
* The layouter performs all the layout work.
*
* It also accounts for the memory allocations and frees.
*/
class Layouter : public AutoDeleteSmallVector {
#ifdef WITH_ICU
typedef UChar CharType; ///< The type of character used within the layouter.
#else /* WITH_ICU */
typedef WChar CharType; ///< The type of character used within the layouter.
#endif /* WITH_ICU */
size_t AppendToBuffer(CharType *buff, const CharType *buffer_last, WChar c);
ParagraphLayout *GetParagraphLayout(CharType *buff, CharType *buff_end, FontMap &fontMapping);
CharType buffer[DRAW_STRING_BUFFER]; ///< Buffer for the text that is going to be drawn.
typedef SmallMap FontColourMap;
static FontColourMap fonts[FS_END];
static Font *GetFont(FontSize size, TextColour colour);
public:
Layouter(const char *str, int maxw = INT32_MAX, TextColour colour = TC_FROMSTRING, FontSize fontsize = FS_NORMAL);
Dimension GetBounds();
static void ResetFontCache(FontSize size);
};
#endif /* GFX_LAYOUT_H */