Source code for toyplot.reportlab.pdf

# Copyright 2014, Sandia Corporation. Under the terms of Contract
# DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains certain
# rights in this software.

"""Functions to render PDF documents using ReportLab."""



import io
import reportlab.pdfgen.canvas
import toyplot.reportlab
import toyplot.require
import toyplot.svg


[docs]def render(canvas, fobj=None, width=None, height=None, scale=None): """Render the PDF representation of a canvas using ReportLab. Because the canvas dimensions are specified explicitly at creation time, they map directly to real-world units in the output PDF image. Use one of `width`, `height`, or `scale` to override this behavior. Parameters ---------- canvas: :class:`toyplot.canvas.Canvas` Canvas to be rendered. fobj: file-like object or string The file to write. Use a string filepath to write data directly to disk. If `None` (the default), the PDF data will be returned to the caller instead. width: number, string, or (number, string) tuple, optional Specify the width of the output image with optional units. If the units aren't specified, defaults to points. See :ref:`units` for details on unit conversion in Toyplot. height: number or (number, string) tuple, optional Specify the height of the output image with optional units. If the units aren't specified, defaults to points. See :ref:`units` for details on unit conversion in Toyplot. scale: number, optional Scales the output `canvas` by the given ratio. Returns ------- pdf: PDF data, or `None` PDF representation of `canvas`, or `None` if the caller specifies the `fobj` parameter. Examples -------- >>> toyplot.reportlab.pdf.render(canvas, "figure-1.pdf", width=(4, "inches")) """ canvas = toyplot.require.instance(canvas, toyplot.canvas.Canvas) svg = toyplot.svg.render(canvas) scale = canvas._point_scale(width=width, height=height, scale=scale) if fobj is None: stream = io.BytesIO() surface = reportlab.pdfgen.canvas.Canvas( stream, pagesize=(scale * canvas.width, scale * canvas.height)) else: surface = reportlab.pdfgen.canvas.Canvas( fobj, pagesize=(scale * canvas.width, scale * canvas.height)) surface.translate(0, scale * canvas.height) surface.scale(1, -1) surface.scale(scale, scale) toyplot.reportlab.render(svg, surface) surface.showPage() surface.save() if fobj is None: return stream.getvalue()