react-native/Libraries/ART/RCTConvert+ART.m

224 lines
6.7 KiB
Objective-C

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
#import "RCTConvert+ART.h"
#import "ARTLinearGradient.h"
#import "ARTPattern.h"
#import "ARTRadialGradient.h"
#import "ARTSolidColor.h"
#import "RCTLog.h"
@implementation RCTConvert (ART)
+ (CGPathRef)CGPath:(id)json
{
NSArray *arr = [self NSNumberArray:json];
NSUInteger count = [arr count];
#define NEXT_VALUE [self double:arr[i++]]
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, 0, 0);
@try {
NSUInteger i = 0;
while (i < count) {
NSUInteger type = [arr[i++] unsignedIntegerValue];
switch (type) {
case 0:
CGPathMoveToPoint(path, NULL, NEXT_VALUE, NEXT_VALUE);
break;
case 1:
CGPathCloseSubpath(path);
break;
case 2:
CGPathAddLineToPoint(path, NULL, NEXT_VALUE, NEXT_VALUE);
break;
case 3:
CGPathAddCurveToPoint(path, NULL, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE);
break;
case 4:
CGPathAddArc(path, NULL, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE, NEXT_VALUE == 0);
break;
default:
RCTLogError(@"Invalid CGPath type %zd at element %zd of %@", type, i, arr);
CGPathRelease(path);
return NULL;
}
}
}
@catch (NSException *exception) {
RCTLogError(@"Invalid CGPath format: %@", arr);
CGPathRelease(path);
return NULL;
}
return (CGPathRef)CFAutorelease(path);
}
RCT_ENUM_CONVERTER(CTTextAlignment, (@{
@"auto": @(kCTTextAlignmentNatural),
@"left": @(kCTTextAlignmentLeft),
@"center": @(kCTTextAlignmentCenter),
@"right": @(kCTTextAlignmentRight),
@"justify": @(kCTTextAlignmentJustified),
}), kCTTextAlignmentNatural, integerValue)
// This takes a tuple of text lines and a font to generate a CTLine for each text line.
// This prepares everything for rendering a frame of text in ARTText.
+ (ARTTextFrame)ARTTextFrame:(id)json
{
NSDictionary *dict = [self NSDictionary:json];
ARTTextFrame frame;
frame.count = 0;
NSArray *lines = [self NSArray:dict[@"lines"]];
NSUInteger lineCount = [lines count];
if (lineCount == 0) {
return frame;
}
NSDictionary *fontDict = dict[@"font"];
CTFontRef font = (__bridge CTFontRef)[self UIFont:nil withFamily:fontDict[@"fontFamily"] size:fontDict[@"fontSize"] weight:fontDict[@"fontWeight"] style:fontDict[@"fontStyle"]];
if (!font) {
return frame;
}
// Create a dictionary for this font
CFDictionaryRef attributes = (__bridge CFDictionaryRef)@{
(NSString *)kCTFontAttributeName: (__bridge id)font,
(NSString *)kCTForegroundColorFromContextAttributeName: @YES
};
// Set up text frame with font metrics
CGFloat size = CTFontGetSize(font);
frame.count = lineCount;
frame.baseLine = size; // estimate base line
frame.lineHeight = size * 1.1; // Base on ART canvas line height estimate
frame.lines = malloc(sizeof(CTLineRef) * lineCount);
frame.widths = malloc(sizeof(CGFloat) * lineCount);
[lines enumerateObjectsUsingBlock:^(NSString *text, NSUInteger i, BOOL *stop) {
CFStringRef string = (__bridge CFStringRef)text;
CFAttributedStringRef attrString = CFAttributedStringCreate(kCFAllocatorDefault, string, attributes);
CTLineRef line = CTLineCreateWithAttributedString(attrString);
CFRelease(attrString);
frame.lines[i] = line;
frame.widths[i] = CTLineGetTypographicBounds(line, NULL, NULL, NULL);
}];
return frame;
}
+ (ARTCGFloatArray)ARTCGFloatArray:(id)json
{
NSArray *arr = [self NSNumberArray:json];
NSUInteger count = arr.count;
ARTCGFloatArray array;
array.count = count;
array.array = NULL;
if (count) {
// Ideally, these arrays should already use the same memory layout.
// In that case we shouldn't need this new malloc.
array.array = malloc(sizeof(CGFloat) * count);
for (NSUInteger i = 0; i < count; i++) {
array.array[i] = [arr[i] doubleValue];
}
}
return array;
}
+ (ARTBrush *)ARTBrush:(id)json
{
NSArray *arr = [self NSArray:json];
NSUInteger type = [self NSUInteger:arr[0]];
switch (type) {
case 0: // solid color
// These are probably expensive allocations since it's often the same value.
// We should memoize colors but look ups may be just as expensive.
return [[ARTSolidColor alloc] initWithArray:arr];
case 1: // linear gradient
return [[ARTLinearGradient alloc] initWithArray:arr];
case 2: // radial gradient
return [[ARTRadialGradient alloc] initWithArray:arr];
case 3: // pattern
return [[ARTPattern alloc] initWithArray:arr];
default:
RCTLogError(@"Unknown brush type: %zd", type);
return nil;
}
}
+ (CGPoint)CGPoint:(id)json offset:(NSUInteger)offset
{
NSArray *arr = [self NSArray:json];
if (arr.count < offset + 2) {
RCTLogError(@"Too few elements in array (expected at least %zd): %@", 2 + offset, arr);
return CGPointZero;
}
return (CGPoint){
[self CGFloat:arr[offset]],
[self CGFloat:arr[offset + 1]],
};
}
+ (CGRect)CGRect:(id)json offset:(NSUInteger)offset
{
NSArray *arr = [self NSArray:json];
if (arr.count < offset + 4) {
RCTLogError(@"Too few elements in array (expected at least %zd): %@", 4 + offset, arr);
return CGRectZero;
}
return (CGRect){
{[self CGFloat:arr[offset]], [self CGFloat:arr[offset + 1]]},
{[self CGFloat:arr[offset + 2]], [self CGFloat:arr[offset + 3]]},
};
}
+ (CGColorRef)CGColor:(id)json offset:(NSUInteger)offset
{
NSArray *arr = [self NSArray:json];
if (arr.count < offset + 4) {
RCTLogError(@"Too few elements in array (expected at least %zd): %@", 4 + offset, arr);
return NULL;
}
return [self CGColor:[arr subarrayWithRange:(NSRange){offset, 4}]];
}
+ (CGGradientRef)CGGradient:(id)json offset:(NSUInteger)offset
{
NSArray *arr = [self NSArray:json];
if (arr.count < offset) {
RCTLogError(@"Too few elements in array (expected at least %zd): %@", offset, arr);
return NULL;
}
arr = [arr subarrayWithRange:(NSRange){offset, arr.count - offset}];
ARTCGFloatArray colorsAndOffsets = [self ARTCGFloatArray:arr];
size_t stops = colorsAndOffsets.count / 5;
CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
CGGradientRef gradient = CGGradientCreateWithColorComponents(
rgb,
colorsAndOffsets.array,
colorsAndOffsets.array + stops * 4,
stops
);
CGColorSpaceRelease(rgb);
free(colorsAndOffsets.array);
return (CGGradientRef)CFAutorelease(gradient);
}
@end