536 lines
20 KiB
Mathematica
536 lines
20 KiB
Mathematica
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/**
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* Copyright (c) 2015-present, Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD-style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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*/
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#import "RCTBorderDrawing.h"
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#import "RCTLog.h"
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static const CGFloat RCTViewBorderThreshold = 0.001;
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BOOL RCTBorderInsetsAreEqual(UIEdgeInsets borderInsets)
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{
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return
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ABS(borderInsets.left - borderInsets.right) < RCTViewBorderThreshold &&
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ABS(borderInsets.left - borderInsets.bottom) < RCTViewBorderThreshold &&
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ABS(borderInsets.left - borderInsets.top) < RCTViewBorderThreshold;
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}
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BOOL RCTCornerRadiiAreEqual(RCTCornerRadii cornerRadii)
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{
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return
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ABS(cornerRadii.topLeft - cornerRadii.topRight) < RCTViewBorderThreshold &&
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ABS(cornerRadii.topLeft - cornerRadii.bottomLeft) < RCTViewBorderThreshold &&
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ABS(cornerRadii.topLeft - cornerRadii.bottomRight) < RCTViewBorderThreshold;
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}
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BOOL RCTBorderColorsAreEqual(RCTBorderColors borderColors)
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{
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return
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CGColorEqualToColor(borderColors.left, borderColors.right) &&
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CGColorEqualToColor(borderColors.left, borderColors.top) &&
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CGColorEqualToColor(borderColors.left, borderColors.bottom);
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}
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RCTCornerInsets RCTGetCornerInsets(RCTCornerRadii cornerRadii,
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UIEdgeInsets edgeInsets)
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{
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return (RCTCornerInsets) {
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{
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MAX(0, cornerRadii.topLeft - edgeInsets.left),
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MAX(0, cornerRadii.topLeft - edgeInsets.top),
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},
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{
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MAX(0, cornerRadii.topRight - edgeInsets.right),
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MAX(0, cornerRadii.topRight - edgeInsets.top),
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},
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{
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MAX(0, cornerRadii.bottomLeft - edgeInsets.left),
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MAX(0, cornerRadii.bottomLeft - edgeInsets.bottom),
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},
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{
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MAX(0, cornerRadii.bottomRight - edgeInsets.right),
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MAX(0, cornerRadii.bottomRight - edgeInsets.bottom),
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}
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};
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}
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static UIEdgeInsets RCTRoundInsetsToPixel(UIEdgeInsets edgeInsets) {
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edgeInsets.top = RCTRoundPixelValue(edgeInsets.top);
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edgeInsets.bottom = RCTRoundPixelValue(edgeInsets.bottom);
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edgeInsets.left = RCTRoundPixelValue(edgeInsets.left);
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edgeInsets.right = RCTRoundPixelValue(edgeInsets.right);
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return edgeInsets;
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}
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static void RCTPathAddEllipticArc(CGMutablePathRef path,
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const CGAffineTransform *m,
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CGPoint origin,
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CGSize size,
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CGFloat startAngle,
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CGFloat endAngle,
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BOOL clockwise)
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{
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CGFloat xScale = 1, yScale = 1, radius = 0;
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if (size.width != 0) {
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xScale = 1;
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yScale = size.height / size.width;
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radius = size.width;
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} else if (size.height != 0) {
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xScale = size.width / size.height;
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yScale = 1;
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radius = size.height;
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}
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CGAffineTransform t = CGAffineTransformMakeTranslation(origin.x, origin.y);
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t = CGAffineTransformScale(t, xScale, yScale);
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if (m != NULL) {
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t = CGAffineTransformConcat(t, *m);
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}
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CGPathAddArc(path, &t, 0, 0, radius, startAngle, endAngle, clockwise);
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}
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CGPathRef RCTPathCreateWithRoundedRect(CGRect bounds,
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RCTCornerInsets cornerInsets,
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const CGAffineTransform *transform)
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{
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const CGFloat minX = CGRectGetMinX(bounds);
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const CGFloat minY = CGRectGetMinY(bounds);
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const CGFloat maxX = CGRectGetMaxX(bounds);
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const CGFloat maxY = CGRectGetMaxY(bounds);
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const CGSize topLeft = {
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MAX(0, MIN(cornerInsets.topLeft.width, bounds.size.width - cornerInsets.topRight.width)),
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MAX(0, MIN(cornerInsets.topLeft.height, bounds.size.height - cornerInsets.bottomLeft.height)),
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};
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const CGSize topRight = {
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MAX(0, MIN(cornerInsets.topRight.width, bounds.size.width - cornerInsets.topLeft.width)),
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MAX(0, MIN(cornerInsets.topRight.height, bounds.size.height - cornerInsets.bottomRight.height)),
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};
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const CGSize bottomLeft = {
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MAX(0, MIN(cornerInsets.bottomLeft.width, bounds.size.width - cornerInsets.bottomRight.width)),
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MAX(0, MIN(cornerInsets.bottomLeft.height, bounds.size.height - cornerInsets.topLeft.height)),
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};
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const CGSize bottomRight = {
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MAX(0, MIN(cornerInsets.bottomRight.width, bounds.size.width - cornerInsets.bottomLeft.width)),
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MAX(0, MIN(cornerInsets.bottomRight.height, bounds.size.height - cornerInsets.topRight.height)),
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};
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CGMutablePathRef path = CGPathCreateMutable();
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RCTPathAddEllipticArc(path, transform, (CGPoint){
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minX + topLeft.width, minY + topLeft.height
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}, topLeft, M_PI, 3 * M_PI_2, NO);
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RCTPathAddEllipticArc(path, transform, (CGPoint){
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maxX - topRight.width, minY + topRight.height
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}, topRight, 3 * M_PI_2, 0, NO);
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RCTPathAddEllipticArc(path, transform, (CGPoint){
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maxX - bottomRight.width, maxY - bottomRight.height
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}, bottomRight, 0, M_PI_2, NO);
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RCTPathAddEllipticArc(path, transform, (CGPoint){
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minX + bottomLeft.width, maxY - bottomLeft.height
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}, bottomLeft, M_PI_2, M_PI, NO);
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CGPathCloseSubpath(path);
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return path;
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}
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static void RCTEllipseGetIntersectionsWithLine(CGRect ellipseBounds,
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CGPoint lineStart,
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CGPoint lineEnd,
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CGPoint intersections[2])
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{
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const CGPoint ellipseCenter = {
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CGRectGetMidX(ellipseBounds),
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CGRectGetMidY(ellipseBounds)
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};
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lineStart.x -= ellipseCenter.x;
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lineStart.y -= ellipseCenter.y;
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lineEnd.x -= ellipseCenter.x;
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lineEnd.y -= ellipseCenter.y;
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const CGFloat m = (lineEnd.y - lineStart.y) / (lineEnd.x - lineStart.x);
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const CGFloat a = ellipseBounds.size.width / 2;
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const CGFloat b = ellipseBounds.size.height / 2;
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const CGFloat c = lineStart.y - m * lineStart.x;
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const CGFloat A = (b * b + a * a * m * m);
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const CGFloat B = 2 * a * a * c * m;
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const CGFloat D = sqrt((a * a * (b * b - c * c)) / A + pow(B / (2 * A), 2));
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const CGFloat x_ = -B / (2 * A);
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const CGFloat x1 = x_ + D;
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const CGFloat x2 = x_ - D;
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const CGFloat y1 = m * x1 + c;
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const CGFloat y2 = m * x2 + c;
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intersections[0] = (CGPoint){x1 + ellipseCenter.x, y1 + ellipseCenter.y};
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intersections[1] = (CGPoint){x2 + ellipseCenter.x, y2 + ellipseCenter.y};
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}
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NS_INLINE BOOL RCTCornerRadiiAreAboveThreshold(RCTCornerRadii cornerRadii) {
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return (cornerRadii.topLeft > RCTViewBorderThreshold ||
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cornerRadii.topRight > RCTViewBorderThreshold ||
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cornerRadii.bottomLeft > RCTViewBorderThreshold ||
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cornerRadii.bottomRight > RCTViewBorderThreshold);
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}
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static CGPathRef RCTPathCreateOuterOutline(BOOL drawToEdge, CGRect rect, RCTCornerRadii cornerRadii) {
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if (drawToEdge) {
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return CGPathCreateWithRect(rect, NULL);
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}
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return RCTPathCreateWithRoundedRect(rect, RCTGetCornerInsets(cornerRadii, UIEdgeInsetsZero), NULL);
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}
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static CGContextRef RCTUIGraphicsBeginImageContext(CGSize size, CGColorRef backgroundColor, BOOL hasCornerRadii, BOOL drawToEdge) {
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const CGFloat alpha = CGColorGetAlpha(backgroundColor);
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const BOOL opaque = (drawToEdge || !hasCornerRadii) && alpha == 1.0;
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UIGraphicsBeginImageContextWithOptions(size, opaque, 0.0);
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return UIGraphicsGetCurrentContext();
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}
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static UIImage *RCTGetSolidBorderImage(RCTCornerRadii cornerRadii,
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CGSize viewSize,
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UIEdgeInsets borderInsets,
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RCTBorderColors borderColors,
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CGColorRef backgroundColor,
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BOOL drawToEdge)
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{
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const BOOL hasCornerRadii = RCTCornerRadiiAreAboveThreshold(cornerRadii);
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const RCTCornerInsets cornerInsets = RCTGetCornerInsets(cornerRadii, borderInsets);
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// Incorrect render for borders that are not proportional to device pixel: borders get stretched and become
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// significantly bigger than expected.
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// Rdar: http://www.openradar.me/15959788
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borderInsets = RCTRoundInsetsToPixel(borderInsets);
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const BOOL makeStretchable =
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(borderInsets.left + cornerInsets.topLeft.width +
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borderInsets.right + cornerInsets.bottomRight.width <= viewSize.width) &&
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(borderInsets.left + cornerInsets.bottomLeft.width +
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borderInsets.right + cornerInsets.topRight.width <= viewSize.width) &&
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(borderInsets.top + cornerInsets.topLeft.height +
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borderInsets.bottom + cornerInsets.bottomRight.height <= viewSize.height) &&
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(borderInsets.top + cornerInsets.topRight.height +
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borderInsets.bottom + cornerInsets.bottomLeft.height <= viewSize.height);
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const UIEdgeInsets edgeInsets = (UIEdgeInsets){
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borderInsets.top + MAX(cornerInsets.topLeft.height, cornerInsets.topRight.height),
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borderInsets.left + MAX(cornerInsets.topLeft.width, cornerInsets.bottomLeft.width),
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borderInsets.bottom + MAX(cornerInsets.bottomLeft.height, cornerInsets.bottomRight.height),
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borderInsets.right + MAX(cornerInsets.bottomRight.width, cornerInsets.topRight.width)
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};
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const CGSize size = makeStretchable ? (CGSize){
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// 1pt for the middle stretchable area along each axis
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edgeInsets.left + 1 + edgeInsets.right,
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edgeInsets.top + 1 + edgeInsets.bottom
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} : viewSize;
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CGContextRef ctx = RCTUIGraphicsBeginImageContext(size, backgroundColor, hasCornerRadii, drawToEdge);
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const CGRect rect = {.size = size};
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CGPathRef path = RCTPathCreateOuterOutline(drawToEdge, rect, cornerRadii);
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if (backgroundColor) {
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CGContextSetFillColorWithColor(ctx, backgroundColor);
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CGContextAddPath(ctx, path);
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CGContextFillPath(ctx);
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}
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CGContextAddPath(ctx, path);
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CGPathRelease(path);
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CGPathRef insetPath = RCTPathCreateWithRoundedRect(UIEdgeInsetsInsetRect(rect, borderInsets), cornerInsets, NULL);
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CGContextAddPath(ctx, insetPath);
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CGContextEOClip(ctx);
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BOOL hasEqualColors = RCTBorderColorsAreEqual(borderColors);
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if ((drawToEdge || !hasCornerRadii) && hasEqualColors) {
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CGContextSetFillColorWithColor(ctx, borderColors.left);
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CGContextAddRect(ctx, rect);
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CGContextAddPath(ctx, insetPath);
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CGContextEOFillPath(ctx);
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} else {
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CGPoint topLeft = (CGPoint){borderInsets.left, borderInsets.top};
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if (cornerInsets.topLeft.width > 0 && cornerInsets.topLeft.height > 0) {
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CGPoint points[2];
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RCTEllipseGetIntersectionsWithLine((CGRect){
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topLeft, {2 * cornerInsets.topLeft.width, 2 * cornerInsets.topLeft.height}
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}, CGPointZero, topLeft, points);
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if (!isnan(points[1].x) && !isnan(points[1].y)) {
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topLeft = points[1];
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}
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}
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CGPoint bottomLeft = (CGPoint){borderInsets.left, size.height - borderInsets.bottom};
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if (cornerInsets.bottomLeft.width > 0 && cornerInsets.bottomLeft.height > 0) {
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CGPoint points[2];
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RCTEllipseGetIntersectionsWithLine((CGRect){
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{bottomLeft.x, bottomLeft.y - 2 * cornerInsets.bottomLeft.height},
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{2 * cornerInsets.bottomLeft.width, 2 * cornerInsets.bottomLeft.height}
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}, (CGPoint){0, size.height}, bottomLeft, points);
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if (!isnan(points[1].x) && !isnan(points[1].y)) {
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bottomLeft = points[1];
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}
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}
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CGPoint topRight = (CGPoint){size.width - borderInsets.right, borderInsets.top};
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if (cornerInsets.topRight.width > 0 && cornerInsets.topRight.height > 0) {
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CGPoint points[2];
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RCTEllipseGetIntersectionsWithLine((CGRect){
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{topRight.x - 2 * cornerInsets.topRight.width, topRight.y},
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{2 * cornerInsets.topRight.width, 2 * cornerInsets.topRight.height}
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}, (CGPoint){size.width, 0}, topRight, points);
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if (!isnan(points[0].x) && !isnan(points[0].y)) {
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topRight = points[0];
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}
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}
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CGPoint bottomRight = (CGPoint){size.width - borderInsets.right, size.height - borderInsets.bottom};
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if (cornerInsets.bottomRight.width > 0 && cornerInsets.bottomRight.height > 0) {
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CGPoint points[2];
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RCTEllipseGetIntersectionsWithLine((CGRect){
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{bottomRight.x - 2 * cornerInsets.bottomRight.width, bottomRight.y - 2 * cornerInsets.bottomRight.height},
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{2 * cornerInsets.bottomRight.width, 2 * cornerInsets.bottomRight.height}
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}, (CGPoint){size.width, size.height}, bottomRight, points);
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if (!isnan(points[0].x) && !isnan(points[0].y)) {
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bottomRight = points[0];
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}
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}
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CGColorRef currentColor = NULL;
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// RIGHT
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if (borderInsets.right > 0) {
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const CGPoint points[] = {
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(CGPoint){size.width, 0},
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topRight,
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bottomRight,
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(CGPoint){size.width, size.height},
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};
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currentColor = borderColors.right;
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CGContextAddLines(ctx, points, sizeof(points)/sizeof(*points));
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}
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// BOTTOM
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if (borderInsets.bottom > 0) {
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const CGPoint points[] = {
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(CGPoint){0, size.height},
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bottomLeft,
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bottomRight,
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(CGPoint){size.width, size.height},
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};
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if (!CGColorEqualToColor(currentColor, borderColors.bottom)) {
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CGContextSetFillColorWithColor(ctx, currentColor);
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CGContextFillPath(ctx);
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currentColor = borderColors.bottom;
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}
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CGContextAddLines(ctx, points, sizeof(points)/sizeof(*points));
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}
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// LEFT
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if (borderInsets.left > 0) {
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const CGPoint points[] = {
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CGPointZero,
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topLeft,
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bottomLeft,
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(CGPoint){0, size.height},
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};
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if (!CGColorEqualToColor(currentColor, borderColors.left)) {
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CGContextSetFillColorWithColor(ctx, currentColor);
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CGContextFillPath(ctx);
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currentColor = borderColors.left;
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}
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CGContextAddLines(ctx, points, sizeof(points)/sizeof(*points));
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}
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// TOP
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if (borderInsets.top > 0) {
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const CGPoint points[] = {
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CGPointZero,
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topLeft,
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topRight,
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(CGPoint){size.width, 0},
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};
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if (!CGColorEqualToColor(currentColor, borderColors.top)) {
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CGContextSetFillColorWithColor(ctx, currentColor);
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CGContextFillPath(ctx);
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currentColor = borderColors.top;
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}
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CGContextAddLines(ctx, points, sizeof(points)/sizeof(*points));
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}
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CGContextSetFillColorWithColor(ctx, currentColor);
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CGContextFillPath(ctx);
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}
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CGPathRelease(insetPath);
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UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
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UIGraphicsEndImageContext();
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if (makeStretchable) {
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image = [image resizableImageWithCapInsets:edgeInsets];
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}
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return image;
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}
|
||
|
|
||
|
// Currently, the dashed / dotted implementation only supports a single colour +
|
||
|
// single width, as that's currently required and supported on Android.
|
||
|
//
|
||
|
// Supporting individual widths + colours on each side is possible by modifying
|
||
|
// the current implementation. The idea is that we will draw four different lines
|
||
|
// and clip appropriately for each side (might require adjustment of phase so that
|
||
|
// they line up but even browsers don't do a good job at that).
|
||
|
//
|
||
|
// Firstly, create two paths for the outer and inner paths. The inner path is
|
||
|
// generated exactly the same way as the outer, just given an inset rect, derived
|
||
|
// from the insets on each side. Then clip using the odd-even rule
|
||
|
// (CGContextEOClip()). This will give us a nice rounded (possibly) clip mask.
|
||
|
//
|
||
|
// +----------------------------------+
|
||
|
// |@@@@@@@@ Clipped Space @@@@@@@@@|
|
||
|
// |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
|
||
|
// |@@+----------------------+@@@@@@@@|
|
||
|
// |@@| |@@@@@@@@|
|
||
|
// |@@| |@@@@@@@@|
|
||
|
// |@@| |@@@@@@@@|
|
||
|
// |@@+----------------------+@@@@@@@@|
|
||
|
// |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
|
||
|
// +----------------------------------+
|
||
|
//
|
||
|
// Afterwards, we create a clip path for each border side (CGContextSaveGState()
|
||
|
// and CGContextRestoreGState() when drawing each side). The clip mask for each
|
||
|
// segment is a trapezoid connecting corresponding edges of the inner and outer
|
||
|
// rects. For example, in the case of the top edge, the points would be:
|
||
|
// - (MinX(outer), MinY(outer))
|
||
|
// - (MaxX(outer), MinY(outer))
|
||
|
// - (MinX(inner) + topLeftRadius, MinY(inner) + topLeftRadius)
|
||
|
// - (MaxX(inner) - topRightRadius, MinY(inner) + topRightRadius)
|
||
|
//
|
||
|
// +------------------+
|
||
|
// |\ /|
|
||
|
// | \ / |
|
||
|
// | \ top / |
|
||
|
// | \ / |
|
||
|
// | \ / |
|
||
|
// | +------+ |
|
||
|
// | | | |
|
||
|
// | | | |
|
||
|
// | | | |
|
||
|
// |left | |right|
|
||
|
// | | | |
|
||
|
// | | | |
|
||
|
// | +------+ |
|
||
|
// | / \ |
|
||
|
// | / \ |
|
||
|
// | / \ |
|
||
|
// | / bottom \ |
|
||
|
// |/ \|
|
||
|
// +------------------+
|
||
|
//
|
||
|
//
|
||
|
// Note that this approach will produce discontinous colour changes at the edge
|
||
|
// (which is okay). The reason is that Quartz does not currently support drawing
|
||
|
// of gradients _along_ a path (NB: clipping a path and drawing a linear gradient
|
||
|
// is _not_ equivalent).
|
||
|
|
||
|
static UIImage *RCTGetDashedOrDottedBorderImage(RCTBorderStyle borderStyle,
|
||
|
RCTCornerRadii cornerRadii,
|
||
|
CGSize viewSize,
|
||
|
UIEdgeInsets borderInsets,
|
||
|
RCTBorderColors borderColors,
|
||
|
CGColorRef backgroundColor,
|
||
|
BOOL drawToEdge)
|
||
|
{
|
||
|
NSCParameterAssert(borderStyle == RCTBorderStyleDashed || borderStyle == RCTBorderStyleDotted);
|
||
|
|
||
|
if (!RCTBorderColorsAreEqual(borderColors) || !RCTBorderInsetsAreEqual(borderInsets)) {
|
||
|
RCTLogWarn(@"Unsupported dashed / dotted border style");
|
||
|
return nil;
|
||
|
}
|
||
|
|
||
|
const CGFloat lineWidth = borderInsets.top;
|
||
|
if (lineWidth <= 0.0) {
|
||
|
return nil;
|
||
|
}
|
||
|
|
||
|
const BOOL hasCornerRadii = RCTCornerRadiiAreAboveThreshold(cornerRadii);
|
||
|
CGContextRef ctx = RCTUIGraphicsBeginImageContext(viewSize, backgroundColor, hasCornerRadii, drawToEdge);
|
||
|
const CGRect rect = {.size = viewSize};
|
||
|
|
||
|
if (backgroundColor) {
|
||
|
CGPathRef outerPath = RCTPathCreateOuterOutline(drawToEdge, rect, cornerRadii);
|
||
|
CGContextAddPath(ctx, outerPath);
|
||
|
CGPathRelease(outerPath);
|
||
|
|
||
|
CGContextSetFillColorWithColor(ctx, backgroundColor);
|
||
|
CGContextFillPath(ctx);
|
||
|
}
|
||
|
|
||
|
// Stroking means that the width is divided in half and grows in both directions
|
||
|
// perpendicular to the path, that's why we inset by half the width, so that it
|
||
|
// reaches the edge of the rect.
|
||
|
CGRect pathRect = CGRectInset(rect, lineWidth / 2.0, lineWidth / 2.0);
|
||
|
CGPathRef path = RCTPathCreateWithRoundedRect(pathRect, RCTGetCornerInsets(cornerRadii, UIEdgeInsetsZero), NULL);
|
||
|
|
||
|
CGFloat dashLengths[2];
|
||
|
dashLengths[0] = dashLengths[1] = (borderStyle == RCTBorderStyleDashed ? 3 : 1) * lineWidth;
|
||
|
|
||
|
CGContextSetLineWidth(ctx, lineWidth);
|
||
|
CGContextSetLineDash(ctx, 0, dashLengths, sizeof(dashLengths) / sizeof(*dashLengths));
|
||
|
|
||
|
CGContextSetStrokeColorWithColor(ctx, [UIColor yellowColor].CGColor);
|
||
|
|
||
|
CGContextAddPath(ctx, path);
|
||
|
CGContextSetStrokeColorWithColor(ctx, borderColors.top);
|
||
|
CGContextStrokePath(ctx);
|
||
|
|
||
|
CGPathRelease(path);
|
||
|
|
||
|
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
|
||
|
UIGraphicsEndImageContext();
|
||
|
|
||
|
return image;
|
||
|
}
|
||
|
|
||
|
UIImage *RCTGetBorderImage(RCTBorderStyle borderStyle,
|
||
|
CGSize viewSize,
|
||
|
RCTCornerRadii cornerRadii,
|
||
|
UIEdgeInsets borderInsets,
|
||
|
RCTBorderColors borderColors,
|
||
|
CGColorRef backgroundColor,
|
||
|
BOOL drawToEdge)
|
||
|
{
|
||
|
|
||
|
switch (borderStyle) {
|
||
|
case RCTBorderStyleSolid:
|
||
|
return RCTGetSolidBorderImage(cornerRadii, viewSize, borderInsets, borderColors, backgroundColor, drawToEdge);
|
||
|
case RCTBorderStyleDashed:
|
||
|
case RCTBorderStyleDotted:
|
||
|
return RCTGetDashedOrDottedBorderImage(borderStyle, cornerRadii, viewSize, borderInsets, borderColors, backgroundColor, drawToEdge);
|
||
|
case RCTBorderStyleUnset:
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
return nil;
|
||
|
}
|