126 lines
3.2 KiB
Objective-C
126 lines
3.2 KiB
Objective-C
/*
|
|
* Copyright (c) Facebook, Inc. and its affiliates.
|
|
*
|
|
* This source code is licensed under the MIT license found in the
|
|
* LICENSE file in the root directory of this source tree.
|
|
*/
|
|
|
|
#import <React/ARTText.h>
|
|
|
|
#import <CoreText/CoreText.h>
|
|
|
|
@implementation ARTText
|
|
|
|
- (void)setAlignment:(CTTextAlignment)alignment
|
|
{
|
|
[self invalidate];
|
|
_alignment = alignment;
|
|
}
|
|
|
|
static void ARTFreeTextFrame(ARTTextFrame frame)
|
|
{
|
|
if (frame.count) {
|
|
// We must release each line before freeing up this struct
|
|
for (int i = 0; i < frame.count; i++) {
|
|
CFRelease(frame.lines[i]);
|
|
}
|
|
free(frame.lines);
|
|
free(frame.widths);
|
|
}
|
|
}
|
|
|
|
- (void)setTextFrame:(ARTTextFrame)frame
|
|
{
|
|
if (frame.lines != _textFrame.lines) {
|
|
ARTFreeTextFrame(_textFrame);
|
|
}
|
|
[self invalidate];
|
|
_textFrame = frame;
|
|
}
|
|
|
|
- (void)dealloc
|
|
{
|
|
ARTFreeTextFrame(_textFrame);
|
|
}
|
|
|
|
- (void)renderLayerTo:(CGContextRef)context
|
|
{
|
|
ARTTextFrame frame = self.textFrame;
|
|
|
|
if ((!self.fill && !self.stroke) || !frame.count) {
|
|
return;
|
|
}
|
|
|
|
// to-do: draw along a path
|
|
|
|
CGTextDrawingMode mode = kCGTextStroke;
|
|
if (self.fill) {
|
|
if ([self.fill applyFillColor:context]) {
|
|
mode = kCGTextFill;
|
|
} else {
|
|
|
|
for (int i = 0; i < frame.count; i++) {
|
|
CGContextSaveGState(context);
|
|
// Inverse the coordinate space since CoreText assumes a bottom-up coordinate space
|
|
CGContextScaleCTM(context, 1.0, -1.0);
|
|
CGContextSetTextDrawingMode(context, kCGTextClip);
|
|
[self renderLineTo:context atIndex:i];
|
|
// Inverse the coordinate space back to the original before filling
|
|
CGContextScaleCTM(context, 1.0, -1.0);
|
|
[self.fill paint:context];
|
|
// Restore the state so that the next line can be clipped separately
|
|
CGContextRestoreGState(context);
|
|
}
|
|
|
|
if (!self.stroke) {
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
if (self.stroke) {
|
|
CGContextSetStrokeColorWithColor(context, self.stroke);
|
|
CGContextSetLineWidth(context, self.strokeWidth);
|
|
CGContextSetLineCap(context, self.strokeCap);
|
|
CGContextSetLineJoin(context, self.strokeJoin);
|
|
ARTCGFloatArray dash = self.strokeDash;
|
|
if (dash.count) {
|
|
CGContextSetLineDash(context, 0, dash.array, dash.count);
|
|
}
|
|
if (mode == kCGTextFill) {
|
|
mode = kCGTextFillStroke;
|
|
}
|
|
}
|
|
|
|
CGContextSetTextDrawingMode(context, mode);
|
|
|
|
// Inverse the coordinate space since CoreText assumes a bottom-up coordinate space
|
|
CGContextScaleCTM(context, 1.0, -1.0);
|
|
for (int i = 0; i < frame.count; i++) {
|
|
[self renderLineTo:context atIndex:i];
|
|
}
|
|
}
|
|
|
|
- (void)renderLineTo:(CGContextRef)context atIndex:(int)index
|
|
{
|
|
ARTTextFrame frame = self.textFrame;
|
|
CGFloat shift;
|
|
switch (self.alignment) {
|
|
case kCTTextAlignmentRight:
|
|
shift = frame.widths[index];
|
|
break;
|
|
case kCTTextAlignmentCenter:
|
|
shift = (frame.widths[index] / 2);
|
|
break;
|
|
default:
|
|
shift = 0;
|
|
break;
|
|
}
|
|
// We should consider snapping this shift to device pixels to improve rendering quality
|
|
// when a line has subpixel width.
|
|
CGContextSetTextPosition(context, -shift, -frame.baseLine - frame.lineHeight * index);
|
|
CTLineRef line = frame.lines[index];
|
|
CTLineDraw(line, context);
|
|
}
|
|
|
|
@end
|