# Paint a broken eggshell in Aquarell: distinguish thin edges, inner wall and outer shell

Language: en
Canonical: [Paint a broken eggshell in Aquarell: distinguish thin edges, inner wall and outer shell](<https://allluckly.cn/en/guides/aquarell-cracked-eggshell/>)
中文：[中文 HTML](<https://allluckly.cn/guides/aquarell-cracked-eggshell/>)
English: [English HTML](<https://allluckly.cn/en/guides/aquarell-cracked-eggshell/>)
Published: 2026-10-27T00:00:00+08:00
Modified: 2026-10-27T13:09:51+08:00
Author: Bison

Study white curved surfaces, broken-edge thickness and interior overlap through two empty shell halves.

English translation of the [Chinese original](<https://allluckly.cn/guides/aquarell-cracked-eggshell/>), translated on 2026-10-27. Original publication dates, attribution, code and version notes are retained.

An empty eggshell is pale but structurally complex: convex outside, concave inside and a thin broken rim. Paint two unequal empty halves, concentrating on differences among whites before selected jagged edges. Dark outlines alone cannot explain the interior.

## Choose two opening directions

Use an approximately 1600×1400 px canvas with two unequal halves facing different directions against pale warm grey. Separate outer shell, inner wall and rim. Establish convex sides and visible interiors before jagged detail, avoiding two flat white cutouts.

## Model the convex outer surface

Use warm off-white lit and cooler pale-grey shaded planes under upper-left light. Reserve purest white locally. Keep the shell opaque: reduce background transmission if it looks transparent, or excessive shadow weight if it resembles solid plaster.

## Differentiate the concave interior

Turn the inner wall darker away from incoming light, not automatically at its geometric centre. Build a pale-grey concavity before selected deeper curves. Avoid a black hole or flat grey patch by linking interior curvature to the same rim as the exterior.

## Select a few clear broken teeth

Use a few unequal teeth rather than a regular crown. Preserve a coherent opening and interrupt occluded teeth. Show a narrow thickness on selected near breaks without turning the rim into thick ceramic. Simplify excessive jagged detail before reinforcing it.

## Separate whites through temperature and value

Test background, lit exterior, shaded exterior and inner wall as four related near-whites. Adjust adjacent plane values before outlining them. Allow selected edges to disappear into the background while retaining opening and base cues; uniformly sharp boundaries make pale material rigid.

## Clarify overlap between the halves

Let the near half interrupt part of the far contour, with a small local shadow and quieter far contrast. Connect separated-looking halves through placement and shared ground, or clarify merged ones through gaps and angle. Resolve space before optional surface speckles.

## Keep contact darker but more concentrated than the rim

Use a small deep-grey contact expanding into a soft pale shadow. Excessive darkness makes the light shell heavy. Review openings and paired placement, checking close up that broken teeth actually change the silhouette rather than merely forming an internal decorative zigzag.

## Study one broken tooth

Enlarge one broken tooth to distinguish outer surface, narrow broken edge and inner wall sharing a tip. Align their common edges before reducing the study to a few marks in the main image. Normal-size suggested thickness matters more than countable microscopic layers.

## Compare greys inside differently facing openings

Compare the two interior greys according to opening direction, keeping a larger lit inner area in the one facing the light. Restrain excessive contrast between halves. This changes illuminated area, not material colour, helping distinguish orientation from arbitrary speckled decoration.

## Compare detailed and simplified breaks

Keep the plain structure and finished PNG with an editable interior. Next, halve the jagged detail while holding light and placement fixed. Identify whether thin edges and concavity still explain broken shell, deliberately choosing useful breaks rather than simply smoothing the finished image.

## Related tutorials and sources

[White forms](<https://allluckly.cn/en/guides/aquarell-cloud-shapes/>), [Container interiors](<https://allluckly.cn/en/guides/aquarell-paint-cup/>).

Checked on October 27, 2026 against the [official Aquarell App Store listing](<https://apps.apple.com/cn/app/id1591340577>) and [Apple’s public version lookup](<https://itunes.apple.com/lookup?id=1591340577&country=cn>): current version 1.0.6, requiring iOS / iPadOS 15.0 or later. This exercise uses public brush, colour, layer and saving capabilities. Geometry, materials and motion cues are drawn manually; dimensions, palettes and simplified forms are suggestions. Check controls in your installed version. Keep the native project for editing and use PNG for previews. No step-by-step physical-device testing is claimed.