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Fix ligature glyph advance value calculation on ios

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This commit is contained in:
Mikael Sand
2017-12-31 15:36:26 +02:00
parent f8b0d34c6a
commit 17a66f3c2c
1 changed files with 54 additions and 60 deletions
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ios/Text/RNSVGTSpan.m
+54 -60
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@@ -696,36 +696,58 @@ NSCharacterSet *separators = nil;
};
}
for(CFIndex g = 0; g < runGlyphCount; g++) {
CGGlyph glyph = glyphs[g];
bool hasLigature = false;
CGFloat charWidth = 0;
double advance = 0;
bool alreadyRenderedGraphemeCluster = ligature[g];
if (!alreadyRenderedGraphemeCluster) {
/*
Determine the glyph's charwidth (i.e., the amount which the current text position
advances horizontally when the glyph is drawn using horizontal text layout).
*/
double unkernedAdvance = CTFontGetAdvancesForGlyphs(fontRef, kCTFontOrientationHorizontal, glyphs + g, NULL, 1);
charWidth = unkernedAdvance * scaleSpacingAndGlyphs;
/*
Determine the glyph's charwidth (i.e., the amount which the current text position
advances horizontally when the glyph is drawn using horizontal text layout).
*/
double unkernedAdvance = CTFontGetAdvancesForGlyphs(fontRef, kCTFontOrientationHorizontal, glyphs + g, NULL, 1);
CGFloat charWidth = unkernedAdvance * scaleSpacingAndGlyphs;
/*
For each subsequent glyph, set a new startpoint-on-the-path as the previous
endpoint-on-the-path, but with appropriate adjustments taking into account
horizontal kerning tables in the font and current values of various attributes
and properties, including spacing properties (e.g. letter-spacing and word-spacing)
and ‘tspan’ elements with values provided for attributes ‘dx’ and ‘dy’. All
adjustments are calculated as distance adjustments along the path, calculated
using the user agent's distance along the path algorithm.
*/
if (autoKerning) {
double kerned = advances[g].width * scaleSpacingAndGlyphs;
kerning = kerned - charWidth;
}
/*
For each subsequent glyph, set a new startpoint-on-the-path as the previous
endpoint-on-the-path, but with appropriate adjustments taking into account
horizontal kerning tables in the font and current values of various attributes
and properties, including spacing properties (e.g. letter-spacing and word-spacing)
and ‘tspan’ elements with values provided for attributes ‘dx’ and ‘dy’. All
adjustments are calculated as distance adjustments along the path, calculated
using the user agent's distance along the path algorithm.
*/
if (autoKerning) {
double kerned = advances[g].width * scaleSpacingAndGlyphs;
kerning = kerned - charWidth;
NSUInteger len = 2;
NSUInteger nextIndex = g;
while (++nextIndex < n) {
NSString* nextLigature = [str substringWithRange:NSMakeRange(g, len++)];
bool hasNextLigature = hasGlyph(fontRef, nextLigature, &glyph, ligattributes);
if (hasNextLigature) {
ligature[nextIndex] = true;
hasLigature = true;
} else {
break;
}
}
if (hasLigature) {
charWidth = CTFontGetAdvancesForGlyphs(fontRef, kCTFontOrientationHorizontal, &glyph, NULL, 1);
}
char currentChar = [str characterAtIndex:g];
bool isWordSeparator = [separators characterIsMember:currentChar];
double wordSpace = isWordSeparator ? wordSpacing : 0;
double spacing = wordSpace + letterSpacing;
advance = charWidth + spacing;
}
char currentChar = [str characterAtIndex:g];
bool isWordSeparator = [separators characterIsMember:currentChar];
double wordSpace = isWordSeparator ? wordSpacing : 0;
double spacing = wordSpace + letterSpacing;
double advance = charWidth + spacing;
double x = [gc nextXWithDouble:kerning + advance];
double x = [gc nextXWithDouble:(alreadyRenderedGraphemeCluster ? 0 : kerning + advance)];
double y = [gc nextY];
double dx = [gc nextDeltaX];
double dy = [gc nextDeltaY];
@@ -736,21 +758,6 @@ NSCharacterSet *separators = nil;
// But, make sure to increment index positions by making gc.next() calls.
continue;
}
NSUInteger len = 2;
NSUInteger nextIndex = g;
CGGlyph glyph = glyphs[g];
bool hasLigature = false;
while (++nextIndex < n) {
NSString* nextLigature = [str substringWithRange:NSMakeRange(g, len++)];
bool hasNextLigature = hasGlyph(fontRef, nextLigature, &glyph, ligattributes);
if (hasNextLigature) {
ligature[nextIndex] = true;
hasLigature = true;
} else {
break;
}
}
CGPathRef glyphPath = CTFontCreatePathForGlyph(runFont, glyph, nil);
advance *= side;
@@ -804,19 +811,20 @@ NSCharacterSet *separators = nil;
CGFloat prevLength = i == 0 ? 0 : [lengths[i - 1] doubleValue];
CGFloat length = totalLength - prevLength;
CGFloat targetPercent = (midPoint - prevLength) / length;
CGFloat percent = (midPoint - prevLength) / length;
NSArray * points = [lines objectAtIndex: i];
CGPoint p1 = [[points objectAtIndex: 0] CGPointValue];
CGPoint p2 = [[points objectAtIndex: 1] CGPointValue];
CGPoint slope;
CGPoint mid = InterpolateLineSegment(p1, p2, targetPercent, &slope);
CGFloat ldx = p2.x - p1.x;
CGFloat ldy = p2.y - p1.y;
CGFloat angle = atan2(ldy, ldx);
// Calculate the rotation
double angle = atan2(slope.y, slope.x);
CGFloat px = p1.x + ldx * percent;
CGFloat py = p1.y + ldy * percent;
transform = CGAffineTransformConcat(CGAffineTransformMakeTranslation(mid.x, mid.y), transform);
transform = CGAffineTransformConcat(CGAffineTransformMakeTranslation(px, py), transform);
transform = CGAffineTransformConcat(CGAffineTransformMakeRotation(angle + r), transform);
transform = CGAffineTransformScale(transform, scaledDirection, side);
transform = CGAffineTransformConcat(CGAffineTransformMakeTranslation(-halfWay, y + dy + baselineShift), transform);
@@ -837,20 +845,6 @@ NSCharacterSet *separators = nil;
return path;
}
CGPoint InterpolateLineSegment(CGPoint p1, CGPoint p2, CGFloat percent, CGPoint *slope)
{
CGFloat dx = p2.x - p1.x;
CGFloat dy = p2.y - p1.y;
if (slope)
*slope = CGPointMake(dx, dy);
CGFloat px = p1.x + dx * percent;
CGFloat py = p1.y + dy * percent;
return CGPointMake(px, py);
}
CGFloat getTextAnchorOffset(enum TextAnchor textAnchor, CGFloat width)
{
switch (textAnchor) {