Struct LayoutCallbackInfoRefData 

#[repr(C)]
pub struct LayoutCallbackInfoRefData<'a> {
    pub image_cache: &'a ImageCache,
    pub gl_context: &'a OptionGlContextPtr,
    pub system_fonts: &'a FcFontCache,
    pub system_style: Arc<SystemStyle>,
    pub active_route: Option<&'a RouteMatch>,
}

Gives the layout() function access to the RendererResources and the Window (for querying images and fonts, as well as width / height) Reference data container for LayoutCallbackInfo (all read-only fields)

This struct consolidates all readonly references that layout callbacks need to query state. By grouping these into a single struct, we reduce the number of parameters to LayoutCallbackInfo::new() from 6 to 2, making the API more maintainable and easier to extend.

This is pure syntax sugar - the struct lives on the stack in the caller and is passed by reference.

Fields

image_cache: &'a ImageCache

Allows the layout() function to reference image IDs

gl_context: &'a OptionGlContextPtr

OpenGL context so that the layout() function can render textures

system_fonts: &'a FcFontCache

Reference to the system font cache

system_style: Arc<SystemStyle>

Platform-specific system style (colors, spacing, etc.) Used for CSD rendering and menu windows.

active_route: Option<&'a RouteMatch>

Active route match (if routing is configured). Contains the matched pattern and extracted parameters.

Trait Implementations

impl<'a> Debug for LayoutCallbackInfoRefData<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.