webdisplay

README

HTTP display implementation for periph.io

A display drawer/driver for the periph.io ecosystem sending updates to the graphics buffer to clients.

Images are encoded using the PNG format and sent as multipart/x-mixed-replace fragments. JPEG is also supported (see Motion JPEG (MJPEG)).

Documentation

Index

• type Drawer
  • func New(opt Options) *Drawer
  • func (d *Drawer) Bounds() image.Rectangle
  • func (d *Drawer) ColorModel() color.Model
  • func (d *Drawer) Draw(dstRect image.Rectangle, src image.Image, srcPts image.Point) error
  • func (d *Drawer) Halt() error
  • func (d *Drawer) ServeHTTP(w http.ResponseWriter, r *http.Request)
  • func (d *Drawer) String() string
• type ImageFormat
  • func ImageFormatFromString(value string) (ImageFormat, error)
  • func (f ImageFormat) String() string
• type Options

Types

type Drawer

type Drawer struct {
	// contains filtered or unexported fields
}

func New

func New(opt Options) *Drawer

New creates a new web display instance.

func (*Drawer) Bounds

func (d *Drawer) Bounds() image.Rectangle

Bounds implements image.Image.

func (*Drawer) ColorModel

func (d *Drawer) ColorModel() color.Model

ColorModel implements image.Image.

func (*Drawer) Draw

func (d *Drawer) Draw(dstRect image.Rectangle, src image.Image, srcPts image.Point) error

Draw implements draw.Image.

func (*Drawer) Halt

func (d *Drawer) Halt() error

Halt implements conn.Resource and terminates all running client requests asynchronously.

func (*Drawer) ServeHTTP

func (d *Drawer) ServeHTTP(w http.ResponseWriter, r *http.Request)

ServeHTTP handles HTTP GET requests and sends a stream of images representing the display buffer in response. The display options control the default format and clients can explicitly request PNG or JPEG images using the "format" parameter ("?format=png", "?format=jpeg").

func (*Drawer) String

func (d *Drawer) String() string

type ImageFormat

type ImageFormat int

const (
	PNG ImageFormat = iota
	JPEG

	DefaultFormat = PNG
)

func ImageFormatFromString

func ImageFormatFromString(value string) (ImageFormat, error)

func (ImageFormat) String

func (f ImageFormat) String() string

type Options

type Options struct {
	// Width and height of the image buffer.
	Width, Height int

	// Format specifies the image format to send to clients.
	Format ImageFormat
}