README
¶
golottie
Render Lottie animations from Bodymovin using headless browser instance.
Basically a simpler transitive-bullshit/puppeteer-lottie rewrite but in GO and with the ability to render frames concurrently
Quick start
Add the following import in your Go module
import "github.com/icyrogue/golottie"
Add the dependency explicitly if you need to
$ go get -u github.com/icyrogue/golottie
For examples checkout the go-reference and examples directory or just use the...
CLI
gollotie provides a simple experimental CLI to render animations localy.
It renders frames by retrieving the SVG data and converting it to PNG using librsvg so install it first.
Note
Some package managers distribute the required rsvg-convert CLI separately
Install it with
$ go install github.com/icyrogue/golottie/cmd/golottie@latest
Usage of golottie:
-b --bufsize frame buffer size
(default: 16)
-c --count worker count (goroutines) to be created for concurrent rendering
(default: 1)
-h --height height of the output
(default: 1080)
-i --input input file name
-o --output output sprintf pattern
-q --quiet should I have a mouth to scream?
(default: false)
-w --width width of the output
(default: 1920)
This CLI is proof of concept that animation can be rendered by multiple concurrent workers specified by --count option.
Note
The width and height have to be specified manually if differ from defaults.
Warning
Changes and optimizations are coming, use it if you dare!
The most obvious optimization is to use memory arena allocation strategy
Rust rewrite?
License
Released under the MIT License
Documentation
¶
Overview ¶
package golottie renders Lottie animations generated by BodyMovin using headless browser instance through chromedp.
For examples checkout go-lottie
Index ¶
- Variables
- func NewContext(ctx context.Context) (context *gContext, cancel context.CancelFunc)
- type Animation
- type AnimationData
- func (a *AnimationData) Close()
- func (a *AnimationData) GetFramesTotal() int
- func (a *AnimationData) GetURL() (url string)
- func (a *AnimationData) WithCustomTemplate(templ *template.Template, data map[string]interface{}) (_ *AnimationData, err error)
- func (a *AnimationData) WithDefaultTemplate() (animation *AnimationData, err error)
- type Context
- type Renderer
Constants ¶
This section is empty.
Variables ¶
Functions ¶
func NewContext ¶
func NewContext(ctx context.Context) (context *gContext, cancel context.CancelFunc)
NewContext wraps a new chromedp context created from parent ctx.
Types ¶
type Animation ¶
type Animation interface {
// GetURL is called by renderer to retrive animation HTML.
GetURL() string
// Close is needed in a case of animation data being served localy.
Close()
// GetFramesTotal returns number of frames to be rendered.
GetFramesTotal() int
}
Animation interface is used by renderer to get animation data.
type AnimationData ¶
type AnimationData struct {
// Template field contains pointer to animation template
// to be reused when parsing multiple animations.
// Equals to nil if animation template hasn't been initialized.
Template *template.Template
// contains filtered or unexported fields
}
AnimationData implements Animation interface to serve animation data localy.
func NewAnimation ¶
func NewAnimation(data []byte) *AnimationData
NewAnimation creates a new animation with data argument as animation data. Template function should be called on resulting animation for it to be completely initialized.
Example:
data, _ := os.ReadFile("animation.json")
animation, err := golottie.NewAnimation(data).WithDefaultTemplate()
if err != nil {
log.Fatal(err)
}
renderer.SetAnimation(animation)
func (*AnimationData) Close ¶
func (a *AnimationData) Close()
Close closes the local server if it exists.
func (*AnimationData) GetFramesTotal ¶
func (a *AnimationData) GetFramesTotal() int
GetFramesTotal is used by renderer to get the amount of frames to render.
func (*AnimationData) GetURL ¶
func (a *AnimationData) GetURL() (url string)
GetURL serves an animation data localy and returns an URL to be used by renderer.
func (*AnimationData) WithCustomTemplate ¶
func (a *AnimationData) WithCustomTemplate(templ *template.Template, data map[string]interface{}) (_ *AnimationData, err error)
WithCustomTemplate initializes animation data using provided custom template. Can be called to reuse animation.Template multiple times.
Example:
data, _ := os.ReadFile("animation.json")
animation, _ := golottie.NewAnimation(data).WithDefaultTemplate()
data, _ = os.ReadFile("animation2.json")
animationTwo, err := golottie.NewAnimation(data).WithCustomTemplate(animation.Template, nil)
if err != nil {
log.Fatal(err.Error)
}
The data arguments map can be provided to be available inside the template. If data map is nil, a new map will be created with "animationData" key containing initial animation data as unescaped JS string. If data map isn't nil, "animationData" key will be added to it.
func (*AnimationData) WithDefaultTemplate ¶
func (a *AnimationData) WithDefaultTemplate() (animation *AnimationData, err error)
WithDefaultTemplate initializes animation data using embedded default template. Returns an error if the initial data is nil or has 0 length.
type Context ¶
Context interface is a custom context which implements context.Context and adds custom error method to contain an error stack.
type Renderer ¶
type Renderer struct {
// contains filtered or unexported fields
}
func (*Renderer) NextFrame ¶
NextFrame advances the current animation frame by one. Returns EOF if there aren't any frames left.
func (*Renderer) RenderFrame ¶
RenderFrame renders current frame as PNG and writes the resulting bytes to the provided frame buffer.
func (*Renderer) RenderFrameSVG ¶
RenderFrameSVG renders current frame as SVG and writes the resulting SVG string to the provided frame buffer.
func (*Renderer) SetAnimation ¶
SetAnimation sets renderer animation. Renderer calls AnimationData.GetFramesTotal and AnimationData.GetURL to update the animation.
Source Files
Directories