LeadKit/Sources/Extensions/Drawing/CGImage/CGImage+Crop.swift

68 lines
2.5 KiB
Swift

//
// Copyright (c) 2017 Touch Instinct
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
import CoreGraphics
public extension CGImage {
/// Crop image to square from center.
///
/// - Returns: A new cropped image or nil if something goes wrong.
func cropFromCenterToSquare() -> CGImage? {
let shortest = min(width, height)
let widthCropSize = width > shortest ? (width - shortest) : 0
let heightCropSize = height > shortest ? (height - shortest) : 0
let left = widthCropSize / 2
let top = heightCropSize / 2
let cropRect = CGRect(x: left,
y: top,
width: width - widthCropSize,
height: height - heightCropSize)
return cropping(to: cropRect)
}
/// Crop image with given margin values.
///
/// - Parameters:
/// - top: Top margin.
/// - left: Left margin.
/// - bottom: Bottom margin.
/// - right: Right margin.
/// - Returns: A new CGImage cropped with given paddings or nil if something goes wrong.
func crop(top: CGFloat = 0,
left: CGFloat = 0,
bottom: CGFloat = 0,
right: CGFloat = 0) -> CGImage? {
let rect = CGRect(x: left,
y: top,
width: CGFloat(width) - left - right,
height: CGFloat(height) - top - bottom)
return cropping(to: rect)
}
}