// TextMetrics returns the vertical metrics based on the current text style.
// Measured values are returned in local coordinate space.
func (c *Context) TextMetrics() (float32, float32, float32) {
state := c.getState()
scale := state.getFontScale() * c.devicePxRatio
invScale := 1.0 / scale
if state.fontID == fontstashmini.INVALID {
return 0, 0, 0
}
c.fs.SetSize(state.fontSize * scale)
c.fs.SetSpacing(state.letterSpacing * scale)
c.fs.SetBlur(state.fontBlur * scale)
c.fs.SetAlign(fontstashmini.FONSAlign(state.textAlign))
c.fs.SetFont(state.fontID)
ascender, descender, lineH := c.fs.VerticalMetrics()
return ascender * invScale, descender * invScale, lineH * invScale
}
// TextGlyphPositionsRune is an alternate version of TextGlyphPositions that accepts rune slice
func (c *Context) TextGlyphPositionsRune(x, y float32, runes []rune) []GlyphPosition {
state := c.getState()
scale := state.getFontScale() * c.devicePxRatio
invScale := 1.0 / scale
if state.fontID == fontstashmini.INVALID {
return nil
}
c.fs.SetSize(state.fontSize * scale)
c.fs.SetSpacing(state.letterSpacing * scale)
c.fs.SetBlur(state.fontBlur * scale)
c.fs.SetAlign(fontstashmini.FONSAlign(state.textAlign))
c.fs.SetFont(state.fontID)
positions := make([]GlyphPosition, 0, len(runes))
iter := c.fs.TextIterForRunes(x*scale, y*scale, runes)
prevIter := iter
for {
quad, ok := iter.Next()
if !ok {
break
}
if iter.PrevGlyph.Index == -1 && !c.allocTextAtlas() {
iter = prevIter
quad, _ = iter.Next() // try again
}
prevIter = iter
positions = append(positions, GlyphPosition{
Index: iter.CurrentIndex,
Runes: runes,
X: iter.X * invScale,
MinX: minF(iter.X, quad.X0) * invScale,
MaxX: minF(iter.NextX, quad.X1) * invScale,
})
}
return positions
}
// TextBounds measures the specified text string. Parameter bounds should be a pointer to float[4],
// if the bounding box of the text should be returned. The bounds value are [xmin,ymin, xmax,ymax]
// Returns the horizontal advance of the measured text (i.e. where the next character should drawn).
// Measured values are returned in local coordinate space.
func (c *Context) TextBounds(x, y float32, str string) (float32, []float32) {
state := c.getState()
scale := state.getFontScale() * c.devicePxRatio
invScale := 1.0 / scale
if state.fontID == fontstashmini.INVALID {
return 0, nil
}
c.fs.SetSize(state.fontSize * scale)
c.fs.SetSpacing(state.letterSpacing * scale)
c.fs.SetBlur(state.fontBlur * scale)
c.fs.SetAlign(fontstashmini.FONSAlign(state.textAlign))
c.fs.SetFont(state.fontID)
width, bounds := c.fs.TextBounds(x*scale, y*scale, str)
if bounds != nil {
bounds[1], bounds[3] = c.fs.LineBounds(y * scale)
bounds[0] *= invScale
bounds[1] *= invScale
bounds[2] *= invScale
bounds[3] *= invScale
}
return width * invScale, bounds
}
// TextRune is an alternate version of Text that accepts rune slice.
func (c *Context) TextRune(x, y float32, runes []rune) float32 {
state := c.getState()
scale := state.getFontScale() * c.devicePxRatio
invScale := 1.0 / scale
if state.fontID == fontstashmini.INVALID {
return 0
}
c.fs.SetSize(state.fontSize * scale)
c.fs.SetSpacing(state.letterSpacing * scale)
c.fs.SetBlur(state.fontBlur * scale)
c.fs.SetAlign(fontstashmini.FONSAlign(state.textAlign))
c.fs.SetFont(state.fontID)
vertexCount := maxI(2, len(runes)) * 4 // conservative estimate.
vertexes := c.cache.allocVertexes(vertexCount)
iter := c.fs.TextIterForRunes(x*scale, y*scale, runes)
prevIter := iter
index := 0
for {
quad, ok := iter.Next()
if !ok {
break
}
if iter.PrevGlyph == nil || iter.PrevGlyph.Index == -1 {
if !c.allocTextAtlas() {
break // no memory :(
}
if index != 0 {
c.renderText(vertexes[:index])
index = 0
}
iter = prevIter
quad, _ = iter.Next() // try again
if iter.PrevGlyph == nil || iter.PrevGlyph.Index == -1 {
// still can not find glyph?
break
}
}
prevIter = iter
// Transform corners.
c0, c1 := state.xform.TransformPoint(quad.X0*invScale, quad.Y0*invScale)
c2, c3 := state.xform.TransformPoint(quad.X1*invScale, quad.Y0*invScale)
c4, c5 := state.xform.TransformPoint(quad.X1*invScale, quad.Y1*invScale)
c6, c7 := state.xform.TransformPoint(quad.X0*invScale, quad.Y1*invScale)
//log.Printf("quad(%c) x0=%d, x1=%d, y0=%d, y1=%d, s0=%d, s1=%d, t0=%d, t1=%d\n", iter.CodePoint, int(quad.X0), int(quad.X1), int(quad.Y0), int(quad.Y1), int(1024*quad.S0), int(quad.S1*1024), int(quad.T0*1024), int(quad.T1*1024))
// Create triangles
if index+4 <= vertexCount {
(&vertexes[index]).set(c2, c3, quad.S1, quad.T0)
(&vertexes[index+1]).set(c0, c1, quad.S0, quad.T0)
(&vertexes[index+2]).set(c4, c5, quad.S1, quad.T1)
(&vertexes[index+3]).set(c6, c7, quad.S0, quad.T1)
index += 4
}
}
c.flushTextTexture()
c.renderText(vertexes[:index])
return iter.X
}
// TextBreakLinesRune is an alternate version of TextBreakLines that accepts rune slice
func (c *Context) TextBreakLinesRune(runes []rune, breakRowWidth float32) []TextRow {
state := c.getState()
scale := state.getFontScale() * c.devicePxRatio
invScale := 1.0 / scale
if state.fontID == fontstashmini.INVALID {
return nil
}
currentType := nvgSPACE
prevType := nvgCHAR
c.fs.SetSize(state.fontSize * scale)
c.fs.SetSpacing(state.letterSpacing * scale)
c.fs.SetBlur(state.fontBlur * scale)
c.fs.SetAlign(fontstashmini.FONSAlign(state.textAlign))
c.fs.SetFont(state.fontID)
breakRowWidth *= scale
iter := c.fs.TextIterForRunes(0, 0, runes)
prevIter := iter
var prevCodePoint rune
var rows []TextRow
var rowStartX, rowWidth, rowMinX, rowMaxX, wordStartX, wordMinX, breakWidth, breakMaxX float32
rowStart := -1
rowEnd := -1
wordStart := -1
breakEnd := -1
for {
quad, ok := iter.Next()
if !ok {
break
}
if iter.PrevGlyph == nil || iter.PrevGlyph.Index == -1 && !c.allocTextAtlas() {
iter = prevIter
quad, _ = iter.Next() // try again
}
prevIter = iter
switch iter.CodePoint {
case 9: // \t
currentType = nvgSPACE
case 11: // \v
currentType = nvgSPACE
case 12: // \f
currentType = nvgSPACE
case 0x00a0: // NBSP
currentType = nvgSPACE
case 10: // \n
if prevCodePoint == 13 {
currentType = nvgNEWLINE
} else {
currentType = nvgSPACE
}
case 13: // \r
if prevCodePoint == 13 {
currentType = nvgNEWLINE
} else {
currentType = nvgSPACE
}
case 0x0085: // NEL
currentType = nvgNEWLINE
default:
currentType = nvgCHAR
}
if currentType == nvgNEWLINE {
// Always handle new lines.
tmpRowStart := rowStart
if rowStart == -1 {
tmpRowStart = iter.CurrentIndex
}
if rowEnd == -1 {
rowEnd = iter.CurrentIndex
}
rows = append(rows, TextRow{
Runes: runes,
StartIndex: tmpRowStart,
EndIndex: rowEnd,
Width: rowWidth * invScale,
MinX: rowMinX * invScale,
MaxX: rowMaxX * invScale,
NextIndex: iter.NextIndex,
})
// Set null break point
breakEnd = rowStart
breakWidth = 0.0
breakMaxX = 0.0
rowStart = -1
rowEnd = -1
rowMinX = 0
rowMaxX = 0
// Indicate to skip the white space at the beginning of the row.
} else {
if rowStart == -1 {
if currentType == nvgCHAR {
// The current char is the row so far
rowStartX = iter.X
rowStart = iter.CurrentIndex
rowEnd = iter.NextIndex
rowWidth = iter.NextX - rowStartX // q.x1 - rowStartX;
rowMinX = quad.X0 - rowStartX
rowMaxX = quad.X1 - rowStartX
wordStart = iter.CurrentIndex
wordStartX = iter.X
wordMinX = quad.X0 - rowStartX
// Set null break point
breakEnd = rowStart
breakWidth = 0.0
breakMaxX = 0.0
}
} else {
nextWidth := iter.NextX - rowStartX
// track last non-white space character
if currentType == nvgCHAR {
rowEnd = iter.NextIndex
rowWidth = iter.NextX - rowStartX
rowMaxX = quad.X1 - rowStartX
}
// track last end of a word
if prevType == nvgCHAR && currentType == nvgSPACE {
breakEnd = iter.CurrentIndex
breakWidth = rowWidth
breakMaxX = rowMaxX
}
// track last beginning of a word
if prevType == nvgSPACE && currentType == nvgCHAR {
wordStart = iter.CurrentIndex
wordStartX = iter.X
wordMinX = quad.X0 - rowStartX
}
// Break to new line when a character is beyond break width.
if currentType == nvgCHAR && nextWidth > breakRowWidth {
// The run length is too long, need to break to new line.
if breakEnd == rowStart {
// The current word is longer than the row length, just break it from here.
rows = append(rows, TextRow{
Runes: runes,
StartIndex: rowStart,
EndIndex: iter.CurrentIndex,
Width: rowWidth * invScale,
MinX: rowMinX * invScale,
MaxX: rowMaxX * invScale,
NextIndex: iter.CurrentIndex,
})
rowStartX = iter.X
rowStart = iter.CurrentIndex
rowEnd = iter.NextIndex
rowWidth = iter.NextX - rowStartX
rowMinX = quad.X0 - rowStartX
rowMaxX = quad.X1 - rowStartX
wordStart = iter.CurrentIndex
wordStartX = iter.X
wordMinX = quad.X0 - rowStartX
} else {
// Break the line from the end of the last word, and start new line from the beginning of the new.
rows = append(rows, TextRow{
Runes: runes,
StartIndex: rowStart,
EndIndex: breakEnd,
Width: breakWidth * invScale,
MinX: rowMinX * invScale,
MaxX: breakMaxX * invScale,
NextIndex: wordStart,
})
rowStartX = wordStartX
rowStart = wordStart
rowEnd = iter.NextIndex
rowWidth = iter.NextX - rowStartX
rowMinX = wordMinX
rowMaxX = quad.X1 - rowStartX
// No change to the word start
}
// Set null break point
breakEnd = rowStart
breakWidth = 0.0
breakMaxX = 0.0
}
}
}
prevCodePoint = iter.CodePoint
prevType = currentType
}
if rowStart != -1 {
rows = append(rows, TextRow{
Runes: runes,
StartIndex: rowStart,
EndIndex: rowEnd,
Width: rowWidth * invScale,
MinX: rowMinX * invScale,
MaxX: rowMaxX * invScale,
NextIndex: len(runes),
})
}
return rows
}