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measuring text width no longer renders the text

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This commit is contained in:
Thomas Friedel 2018-04-14 11:20:54 +02:00
parent 8507e9ed71
commit b32f7eeafc
2 changed files with 10 additions and 5 deletions
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13
freetype.go
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@ -136,8 +136,7 @@ func (c *frContext) drawContour(ps []truetype.Point, dx, dy fixed.Int26_6) {
// rasterize returns the advance width, glyph mask and integer-pixel offset // rasterize returns the advance width, glyph mask and integer-pixel offset
// to render the given glyph at the given sub-pixel offsets. // to render the given glyph at the given sub-pixel offsets.
// The 26.6 fixed point arguments fx and fy must be in the range [0, 1). // The 26.6 fixed point arguments fx and fy must be in the range [0, 1).
func (c *frContext) rasterize(glyph truetype.Index, fx, fy fixed.Int26_6) ( func (c *frContext) rasterize(glyph truetype.Index, fx, fy fixed.Int26_6) (fixed.Int26_6, *image.Alpha, image.Point, error) {
fixed.Int26_6, *image.Alpha, image.Point, error) {
if err := c.glyphBuf.Load(c.f, c.scale, glyph, c.hinting); err != nil { if err := c.glyphBuf.Load(c.f, c.scale, glyph, c.hinting); err != nil {
return 0, nil, image.Point{}, err return 0, nil, image.Point{}, err
@ -173,8 +172,7 @@ func (c *frContext) rasterize(glyph truetype.Index, fx, fy fixed.Int26_6) (
// render the given glyph at the given sub-pixel point. It is a cache for the // render the given glyph at the given sub-pixel point. It is a cache for the
// rasterize method. Unlike rasterize, p's co-ordinates do not have to be in // rasterize method. Unlike rasterize, p's co-ordinates do not have to be in
// the range [0, 1). // the range [0, 1).
func (c *frContext) glyph(glyph truetype.Index, p fixed.Point26_6) ( func (c *frContext) glyph(glyph truetype.Index, p fixed.Point26_6) (fixed.Int26_6, *image.Alpha, image.Point, error) {
fixed.Int26_6, *image.Alpha, image.Point, error) {
// Split p.X and p.Y into their integer and fractional parts. // Split p.X and p.Y into their integer and fractional parts.
ix, fx := int(p.X>>6), p.X&0x3f ix, fx := int(p.X>>6), p.X&0x3f
@ -197,6 +195,13 @@ func (c *frContext) glyph(glyph truetype.Index, p fixed.Point26_6) (
return advanceWidth, mask, offset.Add(image.Point{ix, iy}), nil return advanceWidth, mask, offset.Add(image.Point{ix, iy}), nil
} }
func (c *frContext) glyphAdvance(glyph truetype.Index) (fixed.Int26_6, error) {
if err := c.glyphBuf.Load(c.f, c.scale, glyph, c.hinting); err != nil {
return 0, err
}
return c.glyphBuf.AdvanceWidth, nil
}
const maxInt = int(^uint(0) >> 1) const maxInt = int(^uint(0) >> 1)
// DrawString draws s at p and returns p advanced by the text extent. The text // DrawString draws s at p and returns p advanced by the text extent. The text

2
text.go
View file

@ -160,7 +160,7 @@ func (cv *Canvas) MeasureText(str string) TextMetrics {
} }
x += float64(kern) / 64 x += float64(kern) / 64
} }
advance, _, _, err := frc.glyph(idx, fixed.Point26_6{}) advance, err := frc.glyphAdvance(idx)
if err != nil { if err != nil {
prev = 0 prev = 0
hasPrev = false hasPrev = false