PdfElixide.Geometry.Rect (pdf_elixide v0.23.0)

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An axis-aligned rectangle in PDF user-space coordinates.

PDF user space has a bottom-left origin with y increasing upward, so the origin {x, y} is the bottom-left corner (the minimum x/y); the top edge is y + height and the right edge is x + width. width and height are always non-negative.

Unbounded values

A float the PDF drives past the single-precision range arrives as the largest finite value of that sign, about 3.4e38, and one it leaves undefined as 0.0. No field ever holds an infinity or a NaN. Every float on an extracted struct follows this rule, whichever module carries it.

Rotated pages

to_display_frame/3 and to_user_space/3 move rectangles between raw user space and the displayed frame. See Rotated pages and extracted geometry for which extractor boxes need conversion.

Summary

Types

t()

Functions

to_display_frame(rect, rotation, media_box)

Maps a rectangle in raw, unrotated user space into the displayed frame of a page turned by rotation.

to_user_space(rect, rotation, media_box)

Maps a rectangle in the displayed frame of a page turned by rotation back into raw, unrotated user space.

Types

t()

@type t() :: %PdfElixide.Geometry.Rect{
  height: float(),
  width: float(),
  x: float(),
  y: float()
}

Functions

to_display_frame(rect, rotation, media_box)

@spec to_display_frame(t(), PdfElixide.Document.Page.rotation(), t()) :: t()

Maps a rectangle in raw, unrotated user space into the displayed frame of a page turned by rotation.

Pass the page's PdfElixide.Document.Page.rotation/1 and raw, unswapped PdfElixide.Document.Page.media_box/1. The result is normalized, and to_user_space/3 is the inverse. Only 0, 90, 180 and 270 are accepted; another rotation raises FunctionClauseError.

iex> box = %PdfElixide.Geometry.Rect{x: 10.0, y: 20.0, width: 612.0, height: 792.0}
iex> rect = %PdfElixide.Geometry.Rect{x: 82.0, y: 740.0, width: 100.0, height: 24.0}
iex> PdfElixide.Geometry.Rect.to_display_frame(rect, 90, box)
%PdfElixide.Geometry.Rect{x: 730.0, y: 460.0, width: 24.0, height: 100.0}

to_user_space(rect, rotation, media_box)

@spec to_user_space(t(), PdfElixide.Document.Page.rotation(), t()) :: t()

Maps a rectangle in the displayed frame of a page turned by rotation back into raw, unrotated user space.

This is the inverse of to_display_frame/3 and takes the same raw media box. Convert only boxes known to be in the displayed frame; Telling which frame a box is in explains how to identify them.