func()

in vncclient/encoding.go [103:151]

• 38 lines of code
• 10 McCabe index (conditional complexity)

func (*RawEncoding) Read(c *ClientConn, rect *Rectangle, r io.Reader) (Encoding, error) {
	bytesPerPixel := c.PixelFormat.BPP / 8

	// Various housekeeping helpers
	pixelBytes := make([]uint8, bytesPerPixel)
	var byteOrder binary.ByteOrder = binary.LittleEndian
	if c.PixelFormat.BigEndian {
		byteOrder = binary.BigEndian
	}

	// Output buffer
	colors := make([]Color, rect.Area())

	// Read all needed bytes: this improves performance so we
	// don't have to do piecemeal unbuffered reads.
	buf := make([]byte, rect.Area()*int(bytesPerPixel))
	if _, err := io.ReadFull(r, buf); err != nil {
		return nil, err
	}
	r = bytes.NewBuffer(buf)

	for y := uint16(0); y < rect.Height; y++ {
		for x := uint16(0); x < rect.Width; x++ {
			if _, err := io.ReadFull(r, pixelBytes); err != nil {
				return nil, err
			}

			var rawPixel uint32
			if c.PixelFormat.BPP == 8 {
				rawPixel = uint32(pixelBytes[0])
			} else if c.PixelFormat.BPP == 16 {
				rawPixel = uint32(byteOrder.Uint16(pixelBytes))
			} else if c.PixelFormat.BPP == 32 {
				rawPixel = byteOrder.Uint32(pixelBytes)
			}

			color := &colors[int(y)*int(rect.Width)+int(x)]
			if c.PixelFormat.TrueColor {
				color.R = uint8((rawPixel >> c.PixelFormat.RedShift) & uint32(c.PixelFormat.RedMax))
				color.G = uint8((rawPixel >> c.PixelFormat.GreenShift) & uint32(c.PixelFormat.GreenMax))
				color.B = uint8((rawPixel >> c.PixelFormat.BlueShift) & uint32(c.PixelFormat.BlueMax))
			} else {
				*color = c.ColorMap[rawPixel]
			}
		}
	}

	return &RawEncoding{colors}, nil
}