makeContext.EulerPanel: Set the panel viewport's 'xscale'/'yscale' at draw time.

In eulerr: Area-Proportional Euler and Venn Diagrams

Set the panel viewport's xscale/yscale at draw time.

Description

Fires before grid pushes the panel viewport. We can therefore measure labels against the live cell, run eunoia's placement, and compute a viewport bbox that fits both the diagram and the labels. On window resize grid invalidates the gTree and makeContext re-runs, so the panel grows or shrinks to track the current device and exterior labels never extend past the viewport edge.

Usage

## S3 method for class 'EulerPanel'
makeContext(x)

Arguments

x	an EulerPanel gTree.

Details

Aspect preservation: the new bbox keeps xrng / yrng equal to the geometry's natural aspect (set by setup_geometry()) so that circles render as circles. The smaller dimension is padded if the label-driven canvas bbox is asymmetric.

Value

x, with its viewport's xscale/yscale set to the label-aware bounding box.

eulerr documentation built on Aug. 22, 2026, 1:09 a.m.