Struct rofl::Engine

pub struct Engine<Tl = TemplateLoader, Fl = FontLoader> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>,  { /* fields omitted */ }

Image captioning engine.

The engine is thread-safe (Sync) since normally you'd want the captioning to be performed in a background thread.

Note: Engine implements Clone by merely cloning a shared reference to the underlying object.

Methods

impl Engine<TemplateLoader, FontLoader>

fn new<Dt, Df>(template_directory: Dt, font_directory: Df) -> Self where
    Dt: AsRef<Path>,
    Df: AsRef<Path>, 

Create an Engine which loads templates & fonts from given directory paths. When loaded, both resources will be cached in memory (LRU cache).

impl<Tl, Fl> Engine<Tl, Fl> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>, 

fn with_loaders(template_loader: Tl, font_loader: Fl) -> Self

Create an Engine that uses given loaders for templates & font. When loaded, both resources will be cached in memory (LRU cache).

fn with_raw_loaders(template_loader: Tl, font_loader: Fl) -> Self

Create an Engine that uses given template & font loaders directly. Any caching scheme, if necessary, should be implemented by loaders themselves.

impl<Tl, Fl> Engine<Tl, Fl> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>, 

fn caption(
    &self,
    image_macro: ImageMacro
) -> Result<CaptionOutput, CaptionError<Tl, Fl>>

Render a given image macro by captioning the template with the specified text(s).

Note that captioning is a CPU-intensive process and can be relatively lengthy, especially if the template is an animated GIF. It is recommended to execute it in a separate thread.

impl<Tl, Fl> Engine<Tl, Fl> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>, 

fn preload_template(&self, name: &str) -> Result<(), Tl::Err>

Preemptively load a template into engine's cache.

fn preload_font(&self, name: &str) -> Result<(), Fl::Err>

Preemptively load a font into engine's cache.

fn template_cache(&self) -> Option<&ThreadSafeCache<String, Tl::Item>>

Return a reference to the internal template cache, if any. This can be used to examine cache statistics (hits & misses).

fn font_cache(&self) -> Option<&ThreadSafeCache<String, Fl::Item>>

Return a reference to the internal font cache, if any. This can be used to examine cache statistics (hits & misses).

Trait Implementations

impl<Tl: Clone, Fl: Clone> Clone for Engine<Tl, Fl> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>, 

fn clone(&self) -> Engine<Tl, Fl>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<Tl: Debug, Fl: Debug> Debug for Engine<Tl, Fl> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>, 

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<Tl, Fl> From<Inner<Tl, Fl>> for Engine<Tl, Fl> where
    Tl: Loader<Item = Template>,
    Fl: Loader<Item = Font>, 

fn from(inner: Inner<Tl, Fl>) -> Self

Performs the conversion.