For consistent thin checklist lines, design at the intended PNG dimensions, give repeated elements matching geometry, and inspect their pixel placement before exporting. A stroke-width setting alone cannot ensure equal-looking results at every output size.

This guide covers a checklist graphic made in the current Affinity desktop app on a Mac: repeated empty boxes, horizontal rules, and neutral labels such as “Item A.” The task is to produce a clean PNG at a specific size. Menu paths follow the current Affinity Help Center documentation.

Why can equal-width lines look different?

Start by separating the artwork’s geometry from its pixel preview. Affinity’s Vector view displays smooth vector edges regardless of zoom. Pixel view represents vector artwork as individual pixels, while Retina Pixel view represents its appearance on high-DPI displays. Use View > Mode > Pixels to inspect the design for ordinary image output. View modes

Two rules can have identical stroke widths yet occupy different positions relative to the pixel grid. Affinity explicitly permits partial-pixel positions when Force Pixel Alignment is off. Its documentation also warns that snapping to an object that is off-pixel can produce an off-pixel result even with pixel alignment enabled. Force Pixel Alignment

The practical inference is that matching the width is only one part of the job. Match placement, orientation, and output scale too. For a checklist, compare equivalent features: straight box sides with straight box sides, and horizontal rules with horizontal rules. Rounded corners and diagonal marks are different geometries and should not be judged by whether they occupy identical pixel patterns.

Establish one repeatable line treatment

Select a representative checkbox or rule and open Window > Vector > Stroke. The panel provides line style, width, cap, join, alignment, and pressure controls. For a plain checklist, use a solid line and inspect any pressure profile before treating the width value as evidence of uniform thickness. Keep equivalent elements’ settings alike. Stroke panel

For closed checkbox shapes, choose one stroke alignment consistently. The documented choices place the stroke at the center, inside, or outside of the object edge. Alignment therefore changes where the visible border sits relative to the shape’s geometry. Also check Order: drawing the stroke behind a filled closed shape can hide its inner half. Stroke panel

Check resizing behavior before adjusting a collection of boxes. Scale with Object controls whether the line scales with a closed shape. The Transform panel also has Scale Override, which can force stroke widths and other properties to scale during resizing. If previously resized boxes differ, inspect both controls before assigning a common final width. Stroke panel, Transform panel

For simple horizontal rules, a narrow filled rectangle is another supported construction. The Rectangle Tool supplies fill and stroke controls; the Stroke panel’s None style removes the outline. This lets you specify the rule’s thickness as rectangle height, avoiding the need to reason about a centered stroke. It is an editorial recommendation for straight rules, not a special export feature. Rectangle Tool, Stroke panel

Position the lines precisely on the pixel grid

Open Window > General > Transform. Choose an anchor point deliberately before entering coordinates: the panel’s position and size changes depend on that anchor. It provides exact X, Y, width, height, rotation, and shear values, measured relative to the ruler’s zero point. Keep that origin consistent while comparing repeated objects. Transform panel

For pixel-oriented positioning, open View > Snapping and enable Force Pixel Alignment. Review the other snapping targets as well; an off-pixel guide or object can interfere with a pixel-aligned result. This setting applies as objects are created, moved, or modified, so inspect existing artwork instead of assuming that enabling it has repaired every object. Force Pixel Alignment

Treat Move By Whole Pixels as a movement constraint. Affinity documents that it preserves the partial pixels an object already occupies while moving it by whole-pixel distances. It can preserve an unwanted fractional offset. Establish the intended position first, then use whole-pixel movement when that behavior helps maintain the placement. Force Pixel Alignment

To inspect boundaries closely, enable View > Show > Pixel Grid and zoom in. The grid is a visual aid and does not export. Use it alongside Pixel view to examine equivalent edges, then return to a normal viewing size to judge the checklist as a whole. Grids

An illustrative geometry check

Suppose your checklist’s intended output is 800 × 600 pixels. For a synthetic test, make three filled horizontal rectangles with no stroke. Give each a width of 240 px and a height of 1 px, with the following top-left positions. These are illustrative inputs, not measured Affinity test results.

Rule X Y Width Height
A 80 px 100 px 240 px 1 px
B 80 px 124 px 240 px 1 px
C 80 px 148 px 240 px 1 px

Use the top-left anchor in Transform, enter those values, and keep rotation and shear at zero. The repeated rules now have matching dimensions and whole-pixel spacing. This example uses the Rectangle Tool’s fill controls and the Transform panel’s numerical positioning; it does not depend on an undocumented “crisp lines” command. Rectangle Tool, Transform panel

The scale calculation explains why the destination size matters. Exporting this 800-pixel-wide layout at 400 pixels wide gives a scale factor of 400 ÷ 800 = 0.5. A 1-pixel-high rule then corresponds geometrically to half an output pixel; a 2-pixel-high rule corresponds to one output pixel. These calculations describe the geometry, not a promise about the renderer’s exact shading. If the deliverable is 400 pixels wide, assess and refine the rules for that output.

Export the PNG at the size you actually need

Open File > Export > Export and choose a PNG preset. Set Area deliberately: use the named artboard or appropriate document area for the complete checklist. Selection Area includes overlapping unselected layers, whereas Selection Only excludes them. Different area choices can therefore produce different content. Export dialog

Check the exported width and height. Affinity’s Size setting initially shows native dimensions and allows alternatives; keep Lock aspect ratio enabled for proportional resizing. For the illustrative test, export at 800 × 600 first. Test any smaller deliverable separately. Export Settings

Inspect the export preview before saving. On Mac, press Command-1 while previewing to reach 100%; Command-3 shows 400% for closer inspection. Look for repeated rules that change darkness or apparent thickness, and check whether a border is clipped at the chosen export boundary. Then export and inspect the actual PNG at its intended display size. Export dialog

If resizing is necessary, Affinity offers several resamplers. Its help identifies Nearest Neighbor for hard-edge images and Bilinear for shrinking. Treat those as documented purposes, then compare the preview for your artwork. No resampler is documented as guaranteeing equal-looking thin checklist lines. Export Settings

What can export settings fix—and where are the limits?

The useful boundary is format-specific. Affinity documents Rasterize: Nothing / Everything / Unsupported properties for PDF, SVG, and EPS. It does not list that control for PNG. Likewise, Raster DPI is documented for effects rasterized into those vector-oriented formats. Do not search for a PNG “Rasterize Everything” fix; use the PNG’s output dimensions and correct the artwork’s geometry. Export Settings

Use this diagnostic sequence to decide what to change. It is a decision aid derived from the documented controls, rather than a claim that one setting diagnoses every export problem.

What you observe What to inspect next Practical response
Some boxes have different numerical widths Stroke settings and resizing controls Establish a common final stroke treatment
Equal rules differ in Pixel view Positions, dimensions, and snapping targets Correct equivalent edges and repeat their placement consistently
Lines become uneven only in the smaller export Output dimensions and scale factor Refine the artwork for that smaller size
A rule disappears or meets an unexpected background Export Area and its included layers Select the intended document, artboard, or selection scope
Vector view looks smooth but PNG looks different Pixel view and export preview Judge the raster deliverable using its pixel representation

Once a combination works, save the export choices through Preferences > Create Preset in the Export dialog. A preset makes those export choices reusable; the artwork still needs matching geometry and placement. Export dialog

Keep the final check simple: inspect one representative box and rule, confirm their repeated counterparts match, verify the PNG dimensions, and examine the saved image at the size it will be used. When another output size is required, repeat that check for the new size. Consistency comes from controlling the geometry and scale together.

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