Open Paint.NET layers and preserve special blend modes

A detailed format reference covering retained layers, conversion warnings, unsupported features and a safe exchange workflow.

Applies to Photo 0.9.0 on photo.et.

What this reference covers#

PhotoCraft opens PDN3 .pdn files natively, without Paint.NET, Python, .NET or an external converter. Browser and desktop editions share the importer; use File → Open or drop a file onto the editor. The browser file picker also accepts .pdn.

Each bitmap layer remains editable. Layer order, Unicode names, visibility, opacity and pixel alpha are retained. Painting, masks, transforms, reordering, duplication and undo use the same commands as other pixel layers. All 14 PDN3 blend modes are supported on the CPU and GPU. Reflect, Glow, Negation and XOR have no Photoshop equivalent, and Color Burn and Color Dodge have separate Paint.NET variants because their edge cases differ. The blend menus stay Photoshop's: a layer that uses one of these six modes lists its own mode after Photoshop's, and other layers don't show them.

PDN support is import only. Save opens Save As and suggests .pcraft, which preserves the layers and every blend mode. Exporting as .pdn fails with an explanatory error. PSD cannot represent six Paint.NET variants; exporting those as PSD reports that their blending was changed to Normal. Use .pcraft for continued editing, and PNG for a flattened rendering.

The reader supports PDN3's typed NRBF objects, both numeric and older blend-operation records, BGRA32 surfaces with padded rows, shared pixel memory, and gzip or raw numbered pixel chunks. It validates references, dimensions, strides, counts, chunk ranges and gzip checksums. Metadata object nesting is capped at 64, layers at 1024 and total decoded pixel memory at 1 GiB. Imports can be cancelled while parsing, decompressing or copying pixels. Unsupported layouts and versions return errors. Paint.NET document metadata (including print resolution and profiles) is currently omitted; nonempty user metadata produces an import warning. Layer data is preserved.

Check the imported result#

1. Keep the original file and open a copy with File → Open.
2. Read warnings and compare the visible image with an export from the originating application.
3. Inspect layer names, groups, visibility and blend modes, not just the flattened preview.
4. Download an editable .pcraft working copy before experimenting with other export formats.

A successful open establishes that this file was readable. It does not guarantee support for every version of the originating application or every feature used by that format.

Continue reading

• Layers, groups and blend modes →
• Keep an editable master with .pcraft →