詳解IOS開發GraphicsContext應用類
作者：佚名
IOS開發GraphicsContext應用類是本文要介紹的內容，主要是來認識并學習GraphicsContext應用類的使用方法，具體內容來看本文詳解。
IOS開發GraphicsContext應用類是本文要介紹的內容，主要是來認識并學習GraphicsContext應用類的使用方法，具體內容來看本文詳解。
1、CGContext類。
2、UIView::DrawRect函數
3、UIGraphicsGetCurrentContext()函數
4、UIView坐標系和Quartz坐標系相反。
5、CGContextRef myContext = [[NSGraphicsContext currentContext] graphicsPort];
6、initWithFrame, intWithCoder, DrawRect
7、CGPDFContextCreateWithURL, CGPDFContextCreate
- CFURLCreateWithFileSystemPath(), CGDataConsumerCreateWithURL()
8、iOS 推薦使用 UIGraphicsBeginImageContextWithOptions，它會自動做Quartz和UIKit之間的坐標變換。
9、CGBitmapContextCreate
10、Pixel Format
- NULL color space:
- kCGImageAlphaoOnly 8bpp = A8
Gray color space:
- kCGImageAlphaNone 8bpp = L8
- kCGImageAlphaOnly 8bpp = A8
- kCGImageAlphaNone 16bpp = L16
- KCGImageAlphaNone|kCGBitmapfloatComponents = L32F
RGB color space:
- kCGImageAlphaNoneSkipFirst, 16bpp, 5bpc = R5G5B5X1
- kCGImageAlphaNoneSkipFirst, 32bpp, 8bpc = R8G8B8X8
- kCGImageAlphaNoneSkipLast, 32bpp, 8bpc = X8R8G8B8
- kCGImageAlphaPremultipliedFirst, 32bpp, 8bpc = R8G8B8A8
- kCGImageAlphaPremultipliedLast, 32bpp, 8bpc = A8R8G8B8
- kCGImageAlphaPremultipledLast, 64bpp, 16bpc = A16R16G16B16
- kCGImageAlphaNonSkipLast, 64bpp, 16bpc = X16R16G16B16
- kCGImageAlphaNoneSkipLast|kCGBitmapFloatComponents, 128bpp, 32bpc = X32R32G32B32F
- kCGImageAlphaPremultipliedLast | kCGBitmapFloatComponents, 128bpp, 32bpc = A32R32G32B32F
CMYK space:
- - kCGImageAlphaNone 32bpp, 8bpc = C8M8Y8K8
- kCGImageAlphaNone 64bpp, 16bpx = C16M16Y16K16
- kCGImageAlphaNone|kCGBitmapFloatComponents = C32M32Y32K32F
11、
- CGContextSetShouldAntialias for bitmap context,
- CGContextSetAllowAntialasing for graphics context.
小結：詳解IOS開發GraphicsContext應用類的內容介紹完了，希望通過本文的學習能對你有所幫助！
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