詳解IOS開發(fā)GraphicsContext應(yīng)用類
IOS開發(fā)GraphicsContext應(yīng)用類是本文要介紹的內(nèi)容,主要是來認識并學(xué)習(xí)GraphicsContext應(yīng)用類的使用方法,具體內(nèi)容來看本文詳解。
1、CGContext類。
2、UIView::DrawRect函數(shù)
3、UIGraphicsGetCurrentContext()函數(shù)
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(jié):詳解IOS開發(fā)GraphicsContext應(yīng)用類的內(nèi)容介紹完了,希望通過本文的學(xué)習(xí)能對你有所幫助!















 
 
 
 
 
 
 