diff --git a/text/atlas.go b/text/atlas.go index a8b7d8e..e96929f 100644 --- a/text/atlas.go +++ b/text/atlas.go @@ -3,6 +3,7 @@ package text import ( "image" "image/draw" + "sort" "unicode" "github.com/faiface/pixel" @@ -26,73 +27,52 @@ type Atlas struct { } func NewAtlas(face font.Face, runes []rune) *Atlas { - //FIXME: don't put glyphs in just one row, make a square - - width := fixed.Int26_6(0) - for _, r := range runes { - b, _, ok := face.GlyphBounds(r) - if !ok && r != unicode.ReplacementChar { - continue - } - width += b.Max.X - b.Min.X - - // padding to avoid filtering artifacts - width = fixed.I(width.Ceil()) - width += fixed.I(2) - } + fixedMapping, fixedBounds := makeSquareMapping(face, runes, fixed.I(2)) atlasImg := image.NewRGBA(image.Rect( - 0, 0, - width.Ceil(), (face.Metrics().Ascent + face.Metrics().Descent).Ceil(), + fixedBounds.Min.X.Floor(), + fixedBounds.Min.Y.Floor(), + fixedBounds.Max.X.Ceil(), + fixedBounds.Max.Y.Ceil(), )) - atlasHeight := float64(atlasImg.Bounds().Dy()) - mapping := make(map[rune]Glyph) - - dot := fixed.Point26_6{ - X: 0, - Y: face.Metrics().Ascent, + for r, fg := range fixedMapping { + dr, mask, maskp, _, _ := face.Glyph(fg.dot, r) + draw.Draw(atlasImg, dr, mask, maskp, draw.Src) } - for _, r := range runes { - b, _, ok := face.GlyphBounds(r) - if !ok && r != unicode.ReplacementChar { - continue - } - - dot.X -= b.Min.X - - dr, mask, maskp, _, _ := face.Glyph(dot, r) - draw.Draw(atlasImg, dr, mask, maskp, draw.Src) - - orig := pixel.V( - float64(dot.X)/(1<<6), - atlasHeight-float64(dot.Y)/(1<<6), + bounds := pixel.Rect{} + for _, fg := range fixedMapping { + b := pixel.R( + i2f(fg.frame.Min.X), + i2f(fg.frame.Min.Y), + i2f(fg.frame.Max.X), + i2f(fg.frame.Max.Y), ) + bounds = bounds.Union(b) + } - frame := pixel.R( - float64(dr.Min.X), - atlasHeight-float64(dr.Min.Y), - float64(dr.Max.X), - atlasHeight-float64(dr.Max.Y), - ).Norm() - - adv, _ := face.GlyphAdvance(r) - advance := float64(adv) / (1 << 6) - - mapping[r] = Glyph{orig, frame, advance} - - dot.X += b.Max.X - - // padding - dot.X = fixed.I(dot.X.Ceil()) - dot.X += fixed.I(2) + mapping := make(map[rune]Glyph) + for r, fg := range fixedMapping { + mapping[r] = Glyph{ + Dot: pixel.V( + i2f(fg.dot.X), + bounds.Max.Y()-(i2f(fg.dot.Y)-bounds.Min.Y()), + ), + Frame: pixel.R( + i2f(fg.frame.Min.X), + bounds.Max.Y()-(i2f(fg.frame.Min.Y)-bounds.Min.Y()), + i2f(fg.frame.Max.X), + bounds.Max.Y()-(i2f(fg.frame.Max.Y)-bounds.Min.Y()), + ).Norm(), + Advance: i2f(fg.advance), + } } kern := make(map[struct{ r0, r1 rune }]float64) for _, r0 := range runes { for _, r1 := range runes { - kern[struct{ r0, r1 rune }{r0, r1}] = float64(face.Kern(r0, r1)) / (1 << 6) + kern[struct{ r0, r1 rune }{r0, r1}] = i2f(face.Kern(r0, r1)) } } @@ -100,9 +80,9 @@ func NewAtlas(face font.Face, runes []rune) *Atlas { pic: pixel.PictureDataFromImage(atlasImg), mapping: mapping, kern: kern, - ascent: float64(face.Metrics().Ascent) / (1 << 6), - descent: float64(face.Metrics().Descent) / (1 << 6), - lineHeight: float64(face.Metrics().Height) / (1 << 6), + ascent: i2f(face.Metrics().Ascent), + descent: i2f(face.Metrics().Descent), + lineHeight: i2f(face.Metrics().Height), } } @@ -168,3 +148,74 @@ func (a *Atlas) DrawRune(prevR, r rune, dot pixel.Vec) (rect, frame, bounds pixe return rect, glyph.Frame, bounds, dot } + +type fixedGlyph struct { + dot fixed.Point26_6 + frame fixed.Rectangle26_6 + advance fixed.Int26_6 +} + +func makeSquareMapping(face font.Face, runes []rune, padding fixed.Int26_6) (map[rune]fixedGlyph, fixed.Rectangle26_6) { + width := sort.Search(int(fixed.I(1024*1024)), func(i int) bool { + width := fixed.Int26_6(i) + _, bounds := makeMapping(face, runes, padding, width) + return bounds.Max.X-bounds.Min.X >= bounds.Max.Y-bounds.Min.Y + }) + return makeMapping(face, runes, padding, fixed.Int26_6(width)) +} + +func makeMapping(face font.Face, runes []rune, padding, width fixed.Int26_6) (map[rune]fixedGlyph, fixed.Rectangle26_6) { + mapping := make(map[rune]fixedGlyph) + bounds := fixed.Rectangle26_6{} + + dot := fixed.P(0, 0) + + for _, r := range runes { + // face.Glyph gives more useful results for drawing than face.GlyphBounds + dr, _, _, advance, ok := face.Glyph(fixed.P(0, 0), r) + if !ok { + continue + } + + frame := fixed.Rectangle26_6{ + Min: fixed.P(dr.Min.X, dr.Min.Y), + Max: fixed.P(dr.Max.X, dr.Max.Y), + } + + dot.X -= frame.Min.X + frame = frame.Add(dot) + + mapping[r] = fixedGlyph{ + dot: dot, + frame: frame, + advance: advance, + } + bounds = bounds.Union(frame) + + dot.X = frame.Max.X + + // padding + align to integer + dot.X += padding + dot.X = fixed.I(dot.X.Ceil()) + + // width exceeded, new row + if frame.Max.X >= width { + dot.X = 0 + dot.Y += face.Metrics().Ascent + face.Metrics().Descent + + // padding + align to integer + dot.Y += padding + dot.Y = fixed.I(dot.Y.Ceil()) + } + } + + return mapping, bounds +} + +func i2f(i fixed.Int26_6) float64 { + return float64(i) / (1 << 6) +} + +func f2i(f float64) fixed.Int26_6 { + return fixed.Int26_6(f * (1 << 6)) +} diff --git a/text/text.go b/text/text.go index 83c9801..3c2c338 100644 --- a/text/text.go +++ b/text/text.go @@ -10,6 +10,7 @@ import ( "golang.org/x/image/font" ) +// ASCII is a set of all ASCII runes. These runes are codepoints from 32 to 127 inclusive. var ASCII []rune func init() { @@ -19,6 +20,8 @@ func init() { } } +// RangeTable takes a *unicode.RangeTable and generates a set of runes contained within that +// RangeTable. func RangeTable(table *unicode.RangeTable) []rune { var runes []rune for _, rng := range table.R16 {