react-native/React/Views/RCTBorderDrawing.h

/**
 * 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 <UIKit/UIKit.h>

#import <React/RCTBorderStyle.h>
#import <React/RCTDefines.h>

typedef struct {
  CGFloat topLeft;
  CGFloat topRight;
  CGFloat bottomLeft;
  CGFloat bottomRight;
} RCTCornerRadii;

typedef struct {
  CGSize topLeft;
  CGSize topRight;
  CGSize bottomLeft;
  CGSize bottomRight;
} RCTCornerInsets;

typedef struct {
  CGColorRef top;
  CGColorRef left;
  CGColorRef bottom;
  CGColorRef right;
} RCTBorderColors;

/**
 * Determine if the border widths, colors and radii are all equal.
 */
RCT_EXTERN BOOL RCTBorderInsetsAreEqual(UIEdgeInsets borderInsets);
RCT_EXTERN BOOL RCTCornerRadiiAreEqual(RCTCornerRadii cornerRadii);
RCT_EXTERN BOOL RCTBorderColorsAreEqual(RCTBorderColors borderColors);

/**
 * Convert RCTCornerRadii to RCTCornerInsets by applying border insets.
 * Effectively, returns radius - inset, with a lower bound of 0.0.
 */
RCT_EXTERN RCTCornerInsets RCTGetCornerInsets(RCTCornerRadii cornerRadii,
                                              UIEdgeInsets borderInsets);

/**
 * Create a CGPath representing a rounded rectangle with the specified bounds
 * and corner insets. Note that the CGPathRef must be released by the caller.
 */
RCT_EXTERN CGPathRef RCTPathCreateWithRoundedRect(CGRect bounds,
                                                  RCTCornerInsets cornerInsets,
                                                  const CGAffineTransform *transform);

/**
 * Draw a CSS-compliant border as an image. You can determine if it's scalable
 * by inspecting the image's `capInsets`.
 *
 * `borderInsets` defines the border widths for each edge.
 */
RCT_EXTERN UIImage *RCTGetBorderImage(RCTBorderStyle borderStyle,
                                      CGSize viewSize,
                                      RCTCornerRadii cornerRadii,
                                      UIEdgeInsets borderInsets,
                                      RCTBorderColors borderColors,
                                      CGColorRef backgroundColor,
                                      BOOL drawToEdge);