font.h
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program 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, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef GRAPHICS_FONT_H
#define GRAPHICS_FONT_H
#include "common/str.h"
#include "common/ustr.h"
#include "common/rect.h"
namespace Common {
template<class T> class Array;
}
namespace Graphics {
/**
* @defgroup graphics_font Fonts
* @ingroup graphics
*
* @brief API for representing and managing fonts on the screen.
*
* @{
*/
struct Surface;
class ManagedSurface;
/** Text alignment modes. */
enum TextAlign {
kTextAlignInvalid, ///< Indicates invalid alignment.
kTextAlignStart, ///< Align the text to start of line (virtual).
kTextAlignLeft, ///< Align the text to the left.
kTextAlignCenter, ///< Center the text.
kTextAlignEnd, ///< Align the text to end of line (virtual).
kTextAlignRight ///< Align the text to the right.
};
/** Word wrapping modes. */
enum WordWrapMode {
kWordWrapDefault = 0, ///< Default wrapping mode.
kWordWrapEvenWidthLines = 1 << 0, ///< Make the resulting line segments close to the same width.
kWordWrapOnExplicitNewLines = 1 << 1 ///< Text is wrapped on new lines. Otherwise, treats them as single whitespace.
};
/**
* Convert virtual text alignments (start + end)
* to actual text alignment (left + right + center) for drawing.
*
* If actual text alignment is provided, it is returned as-is.
*
* @param alignH The horizontal alignment to convert.
* @param rtl Indicates whether this is an RTL (right-to-left) language (such as Hebrew),
* or a left-to-right language (such as English).
*/
TextAlign convertTextAlignH(TextAlign alignH, bool rtl);
/**
* Instances of this class represent a distinct font, with a built-in renderer.
*
* @todo Maybe move the high-level methods (drawString etc.) to a separate
* FontRenderer class? That way, we could have different variants... ?
*/
class Font {
public:
Font() {}
virtual ~Font() {}
/**
* Return the height of the font.
*
* @return Font height in pixels.
*/
virtual int getFontHeight() const = 0;
/**
* Returns the font's name, if one is available
*/
virtual Common::String getFontName() const { return ""; }
/**
* Return the ascent of the font.
*
* @return Font ascent in pixels. If it is unknown
* a value of -1 is returned.
*/
virtual int getFontAscent() const;
/**
* Return the descent of the font.
*
* @return Font descent in pixels. If it is unknown
* a value of -1 is returned.
*/
virtual int getFontDescent() const;
/**
* Return the leading of the font.
* This is the distance between the descent line
* and the ascent line below it.
*
* @return Font leading in pixels. If it is unknown
* a value of -1 is returned.
*/
virtual int getFontLeading() const;
/**
* Return the maximum width of the font.
*
* @return Maximum font width in pixels.
*/
virtual int getMaxCharWidth() const = 0;
/**
* Return the width of a specific character.
*
* @param chr The character to query the width of.
*
* @return The width of the character in pixels.
*/
virtual int getCharWidth(uint32 chr) const = 0;
/**
* Query the kerning offset between two characters.
*
* @param left Left character. Can be 0.
* @param right Right character. Can be 0.
*
* @return The horizontal displacement.
*/
virtual int getKerningOffset(uint32 left, uint32 right) const;
/**
* Calculate the bounding box of a character.
*
* It is assumed that the character shall be drawn at position (0, 0).
*
* The idea here is that the character might be drawn outside the
* rect (0, 0) to (getCharWidth(chr), getFontHeight()) for some fonts.
* This is common among TTF fonts.
*
* The default implementation simply returns the rect with a width
* of getCharWidth(chr) and height of getFontHeight().
*
* @param chr The character to draw.
*
* @return The bounding box of the drawn glyph.
*/
virtual Common::Rect getBoundingBox(uint32 chr) const;
/**
* Return the bounding box of a string drawn with drawString.
*
* @param str The drawn string.
* @param x The x position where to start drawing.
* @param y The y position where to start drawing.
* @param w Width of the text area. This can be 0 to allow for
* obtaining the whole bounding box for a string. Note that this
* does not work with an align different than kTextAlignLeft or
* with @p useEllipsis.
* @param align Text alignment. This can be used to center a string
* in the given area or to align it to the right.
* @param deltax Offset to the x starting position of the string.
* @param useEllipsis Try to fit the string in the area by inserting an
* ellipsis. Note that the default value is false for this
* argument, unlike for drawString.
*
* @return The actual area where the string is drawn.
*/
Common::Rect getBoundingBox(const Common::String &str, int x = 0, int y = 0, const int w = 0, TextAlign align = kTextAlignLeft, int deltax = 0, bool useEllipsis = false) const;
/** @overload */
Common::Rect getBoundingBox(const Common::U32String &str, int x = 0, int _y = 0, const int w = 0, TextAlign align = kTextAlignLeft, int deltax = 0, bool useEllipsis = false) const;
/**
* Draw a character at a specific point on the surface.
*
* Note that the point describes the top left edge point where to draw
* the character. This can be different from the top left edge point of the
* character's bounding box. For example, TTF fonts sometimes move
* characters like 't' by one (or more) pixels to the left to create better
* visual results. To query the actual bounding box of a character, use
* getBoundingBox.
* @see getBoundingBox
*
* The Font implementation should take care of not drawing outside of the
* specified surface.
*
* @param dst The surface to draw on.
* @param chr The character to draw.
* @param x The x coordinate where to draw the character.
* @param y The y coordinate where to draw the character.
* @param color The color of the character.
*/
virtual void drawChar(Surface *dst, uint32 chr, int x, int y, uint32 color) const = 0;
virtual void drawChar(ManagedSurface *dst, uint32 chr, int x, int y, uint32 color) const;
/** @overload */
/**
* Draw the given @p str string to the given @p dst surface.
*
* @param dst The surface on which to draw the string.
* @param str The string to draw.
* @param x The x position where to start drawing.
* @param y The y position where to start drawing.
* @param w Width of the text area.
* @param color The color with which to draw the string.
* @param align Text alignment. This can be used to center the string in the given area or to align it to the right.
* @param deltax Offset to the x starting position of the string.
* @param useEllipsis Use ellipsis if needed to fit the string in the area.
*
*/
void drawString(Surface *dst, const Common::String &str, int x, int y, int w, uint32 color, TextAlign align = kTextAlignLeft, int deltax = 0, bool useEllipsis = false) const;
/** @overload */
void drawString(Surface *dst, const Common::U32String &str, int x, int y, int w, uint32 color, TextAlign align = kTextAlignLeft, int deltax = 0, bool useEllipsis = false) const;
/** @overload */
void drawString(ManagedSurface *dst, const Common::String &str, int x, int _y, int w, uint32 color, TextAlign align = kTextAlignLeft, int deltax = 0, bool useEllipsis = false) const;
/** @overload */
void drawString(ManagedSurface *dst, const Common::U32String &str, int x, int y, int w, uint32 color, TextAlign align = kTextAlignLeft, int deltax = 0, bool useEllipsis = false) const;
/**
* Compute and return the width of the string @p str when rendered using this font.
*
* This describes the logical width of the string when drawn at (0, 0).
* This can be different from the actual bounding box of the string. Use
* getBoundingBox when you need the bounding box of a drawn string.
* @see getBoundingBox
* @see drawChar
*/
int getStringWidth(const Common::String &str) const;
/** @overload */
int getStringWidth(const Common::U32String &str) const;
/**
* Word-wrap a text (that can contain newline characters) so that
* no text line is wider than @p maxWidth pixels.
*
* If necessary, additional line breaks are generated, preferably between
* words, where whitespace is. The resulting lines are appended
* to the @p lines string list. This returns the maximal width of any of the new
* lines (i.e. a value that is smaller or equal to maxWidth).
*
* @param str The string to word-wrap.
* @param maxWidth Maximum width that a line can have.
* @param lines The string list to which the text lines from @p str are appended.
* @param initWidth Starting width of the first line, for partially filled lines (optional).
* @param mode Wrapping mode. A bitfield of @c WordWrapMode values.
*
* @return The maximal width of any of the lines added to @p lines.
*/
int wordWrapText(const Common::String &str, int maxWidth, Common::Array<Common::String> &lines, int initWidth = 0, uint32 mode = kWordWrapOnExplicitNewLines) const;
/** @overload */
int wordWrapText(const Common::U32String &str, int maxWidth, Common::Array<Common::U32String> &lines, int initWidth = 0, uint32 mode = kWordWrapOnExplicitNewLines) const;
};
/** @} */
} // End of namespace Graphics
#endif
