From 500caaeda74dd9c660279036293f4b2997cf0b03 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Sat, 9 Sep 2017 09:42:37 +0200 Subject: Add vendor --- vendor/github.com/llgcode/draw2d/draw2dimg/text.go | 82 ++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 vendor/github.com/llgcode/draw2d/draw2dimg/text.go (limited to 'vendor/github.com/llgcode/draw2d/draw2dimg/text.go') diff --git a/vendor/github.com/llgcode/draw2d/draw2dimg/text.go b/vendor/github.com/llgcode/draw2d/draw2dimg/text.go new file mode 100644 index 0000000..2fe2493 --- /dev/null +++ b/vendor/github.com/llgcode/draw2d/draw2dimg/text.go @@ -0,0 +1,82 @@ +package draw2dimg + +import ( + "github.com/golang/freetype/truetype" + "github.com/llgcode/draw2d" + + "golang.org/x/image/math/fixed" +) + +// DrawContour draws the given closed contour at the given sub-pixel offset. +func DrawContour(path draw2d.PathBuilder, ps []truetype.Point, dx, dy float64) { + if len(ps) == 0 { + return + } + startX, startY := pointToF64Point(ps[0]) + path.MoveTo(startX+dx, startY+dy) + q0X, q0Y, on0 := startX, startY, true + for _, p := range ps[1:] { + qX, qY := pointToF64Point(p) + on := p.Flags&0x01 != 0 + if on { + if on0 { + path.LineTo(qX+dx, qY+dy) + } else { + path.QuadCurveTo(q0X+dx, q0Y+dy, qX+dx, qY+dy) + } + } else { + if on0 { + // No-op. + } else { + midX := (q0X + qX) / 2 + midY := (q0Y + qY) / 2 + path.QuadCurveTo(q0X+dx, q0Y+dy, midX+dx, midY+dy) + } + } + q0X, q0Y, on0 = qX, qY, on + } + // Close the curve. + if on0 { + path.LineTo(startX+dx, startY+dy) + } else { + path.QuadCurveTo(q0X+dx, q0Y+dy, startX+dx, startY+dy) + } +} + +func pointToF64Point(p truetype.Point) (x, y float64) { + return fUnitsToFloat64(p.X), -fUnitsToFloat64(p.Y) +} + +func fUnitsToFloat64(x fixed.Int26_6) float64 { + scaled := x << 2 + return float64(scaled/256) + float64(scaled%256)/256.0 +} + +// FontExtents contains font metric information. +type FontExtents struct { + // Ascent is the distance that the text + // extends above the baseline. + Ascent float64 + + // Descent is the distance that the text + // extends below the baseline. The descent + // is given as a negative value. + Descent float64 + + // Height is the distance from the lowest + // descending point to the highest ascending + // point. + Height float64 +} + +// Extents returns the FontExtents for a font. +// TODO needs to read this https://developer.apple.com/fonts/TrueType-Reference-Manual/RM02/Chap2.html#intro +func Extents(font *truetype.Font, size float64) FontExtents { + bounds := font.Bounds(fixed.Int26_6(font.FUnitsPerEm())) + scale := size / float64(font.FUnitsPerEm()) + return FontExtents{ + Ascent: float64(bounds.Max.Y) * scale, + Descent: float64(bounds.Min.Y) * scale, + Height: float64(bounds.Max.Y-bounds.Min.Y) * scale, + } +} -- cgit v1.2.3