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\alias{cairo-scaled-font}
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\alias{CairoScaledFont}
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\alias{CairoFontExtents}
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\alias{CairoTextExtents}
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\alias{cairoScaledFont}
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\name{cairo-scaled-font}
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\title{cairo_scaled_font_t}
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\description{Font face at particular size and options}
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\section{Methods and Functions}{
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\code{\link{cairoScaledFontCreate}(font.face, font.matrix, ctm, option)}\cr
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\code{\link{cairoScaledFontStatus}(scaled.font)}\cr
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\code{\link{cairoScaledFontExtents}(scaled.font)}\cr
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\code{\link{cairoScaledFontTextExtents}(scaled.font, utf8)}\cr
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\code{\link{cairoScaledFontGlyphExtents}(scaled.font, glyphs, num.glyphs)}\cr
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\code{\link{cairoScaledFontTextToGlyphs}(scaled.font, x, y, utf8, utf8.len = -1)}\cr
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\code{\link{cairoScaledFontGetFontFace}(scaled.font)}\cr
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\code{\link{cairoScaledFontGetFontOptions}(scaled.font)}\cr
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\code{\link{cairoScaledFontGetFontMatrix}(scaled.font)}\cr
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\code{\link{cairoScaledFontGetCtm}(scaled.font)}\cr
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\code{\link{cairoScaledFontGetScaleMatrix}(scaled.font)}\cr
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\code{\link{cairoScaledFontGetType}(scaled.font)}\cr
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\code{\link{cairoScaledFontSetUserData}(scaled.font, key, user.data)}\cr
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\code{\link{cairoScaledFontGetUserData}(scaled.font, key)}\cr
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\code{cairoScaledFont(font.face, font.matrix, ctm, option)}
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\section{Detailed Description}{\code{\link{CairoScaledFont}} represents a realization of a font face at a particular
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size and transformation and a certain set of font options.}
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\section{Structures}{\describe{
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\item{\verb{CairoScaledFont}}{
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A \code{\link{CairoScaledFont}} is a font scaled to a particular size and device
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resolution. A \code{\link{CairoScaledFont}} is most useful for low-level font
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usage where a library or application wants to cache a reference
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to a scaled font to speed up the computation of metrics.
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There are various types of scaled fonts, depending on the
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\dfn{font backend} they use. The type of a
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scaled font can be queried using \code{\link{cairoScaledFontGetType}}.
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Memory management of \code{\link{CairoScaledFont}} is done with
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\code{cairoScaledFontReference()} and \code{cairoScaledFontDestroy()}.
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\item{\verb{CairoFontExtents}}{
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The \code{\link{CairoFontExtents}} structure stores metric information for
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a font. Values are given in the current user-space coordinate
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Because font metrics are in user-space coordinates, they are
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mostly, but not entirely, independent of the current transformation
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matrix. If you call \code{cairo_scale(cr, 2.0, 2.0)},
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text will be drawn twice as big, but the reported text extents will
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not be doubled. They will change slightly due to hinting (so you
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can't assume that metrics are independent of the transformation
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matrix), but otherwise will remain unchanged.
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\strong{\verb{CairoFontExtents} is a \link{transparent-type}.}
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\item{\verb{ascent}}{[numeric] the distance that the font extends above the baseline.
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Note that this is not always exactly equal to the maximum
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of the extents of all the glyphs in the font, but rather
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is picked to express the font designer's intent as to
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how the font should align with elements above it.}
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\item{\verb{descent}}{[numeric] the distance that the font extends below the baseline.
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This value is positive for typical fonts that include
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portions below the baseline. Note that this is not always
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exactly equal to the maximum of the extents of all the
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glyphs in the font, but rather is picked to express the
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font designer's intent as to how the the font should
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align with elements below it.}
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\item{\verb{height}}{[numeric] the recommended vertical distance between baselines when
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setting consecutive lines of text with the font. This
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is greater than \code{ascent}+\code{descent} by a
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quantity known as the \dfn{line spacing}
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or \dfn{external leading}. When space
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is at a premium, most fonts can be set with only
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a distance of \code{ascent}+\code{descent} between lines.}
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\item{\verb{maxXAdvance}}{[numeric] the maximum distance in the X direction that
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the the origin is advanced for any glyph in the font.}
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\item{\verb{maxYAdvance}}{[numeric] the maximum distance in the Y direction that
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the the origin is advanced for any glyph in the font.
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this will be zero for normal fonts used for horizontal
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writing. (The scripts of East Asia are sometimes written
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\item{\verb{CairoTextExtents}}{
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The \code{\link{CairoTextExtents}} structure stores the extents of a single
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glyph or a string of glyphs in user-space coordinates. Because text
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extents are in user-space coordinates, they are mostly, but not
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entirely, independent of the current transformation matrix. If you call
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\code{cairo_scale(cr, 2.0, 2.0)}, text will
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be drawn twice as big, but the reported text extents will not be
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doubled. They will change slightly due to hinting (so you can't
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assume that metrics are independent of the transformation matrix),
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but otherwise will remain unchanged.
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\item{\verb{xBearing}}{[numeric] the horizontal distance from the origin to the
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leftmost part of the glyphs as drawn. Positive if the
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glyphs lie entirely to the right of the origin.}
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\item{\verb{yBearing}}{[numeric] the vertical distance from the origin to the
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topmost part of the glyphs as drawn. Positive only if the
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glyphs lie completely below the origin; will usually be
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\item{\verb{width}}{[numeric] width of the glyphs as drawn}
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\item{\verb{height}}{[numeric] height of the glyphs as drawn}
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\item{\verb{xAdvance}}{[numeric] distance to advance in the X direction
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after drawing these glyphs}
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\item{\verb{yAdvance}}{[numeric] distance to advance in the Y direction
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after drawing these glyphs. Will typically be zero except
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for vertical text layout as found in East-Asian languages.}
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\section{Convenient Construction}{\code{cairoScaledFont} is the equivalent of \code{\link{cairoScaledFontCreate}}.}
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\references{\url{http://www.cairographics.org/manual/cairo-scaled-font.html}}
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\author{Derived by RGtkGen from GTK+ documentation}
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man/cairo-scaled-font.Rd
