@spec line_height(Blendend.Text.Font.t(), number()) :: float()

Returns a reasonable line height for font.

Uses ascent + descent + line_gap from Font.metrics!/1. Handy when you need baseline-to-baseline spacing for manual layout (stacking multiple text lines, positioning labels in a UI, or estimating vertical space) without pulling the full metrics map.

Examples

alias Blendend.Text.{Face, Font, Layout}

face = Face.load!("priv/fonts/Alegreya-Regular.otf")
font = Font.create!(face, 12)
Layout.line_height(font)
16.332000255584717

@spec measure(Blendend.Text.Font.t(), String.t()) :: map()

Measures the layout metrics for a UTF-8 string rendered with font (advance vector and tight bounding box).

Returns a map of text metrics with the following keys:

• "advance_x" / "advance_y" – total pen movement after drawing the run
• "bbox_x0" / "bbox_y0" – lower-left corner of the run's tight bounding box
• "bbox_x1" / "bbox_y1" – upper-right corner of the run's tight bounding box

The bounding box is expressed in user space, relative to the text baseline at {0, 0}.

Examples

alias Blendend.Text.{Face, Font, Layout}

face = Face.load!("priv/fonts/Alegreya-Regular.otf")
font = Font.create!(face, 12)
Layout.measure(font, "abc")
%{
  "advance_x" => 16.776,
  "advance_y" => -0.0,
  "bbox_x0" => 0.492,
  "bbox_x1" => 16.332,
  "bbox_y0" => -0.0,
  "bbox_y1" => -0.0
}