A bitmap resource is a resource in a Substance Package. It is different from the atomic bitmap node. The atomic Bitmap node is a specific representation of that bitmap inside a Substance graph.

Bitmaps are some of the most common non-Graph resources in Substance 3D Designer, usually their usage falls in one of the following categories:

• A baked map, either baked internally by Designer, or externally by another application.
• A helper texture, like a pattern, grunge map or decal.
• A simple grayscale mask for blending, either created internally using the bitmap node, or with an external app.

Bitmap storage

Bitmaps are usually the largest resource that Designer deals with. That's why it's good you understand how Designer handles these files with its two main filetypes.

In Substance 3D files (SBS)

How bitmaps are stored in SBS depends on if you Link or Import them, make sure you are familiar with the concept first. Imported bitmaps can be edited using the Bitmap painting tools.

Unlike SVG (Vector Graphics) Resources, Bitmaps are always stored externally, even when created as a new resource, or imported. For new Substance Packages, they are kept in memory, until the .SBS file is saved to disk. Once saved to disk, bitmaps are stored in a /resources folder next to the SBS file.

In Substance 3D assets (SBSAR)

In SBSAR files, Bitmaps are embedded, meaning they have a large impact on the final SBSAR filesize. You can read more about the impact on filesize further on this page. When SBSAR files are published, only bitmaps that are used to compute an output of a graph are embedded. Any unused bitmaps are optimized and excluded from the final SBSAR package, with no effect on the filesize.

File type, color mode and resolution

Substance 3D Designer can easily edit and re-arrange data from bitmaps, but it is best to keep the following in mind:

• Set your resolutions to be power of 2 compliant, that means follow standard realtime texture size like 256, 512, 1024 ,2048, etc. Designer will rescale textures outside of this range to the closest matching resolution. Note that they don't have to be in square proportions.
• Many filetypes are supported, but choose one that is best for your usecase. Lossless compression or even uncompressed filetypes like PNG or TGA give better quality than JPG or DDS.
• Make sure to set up your color mode correctly, depending on whether you need color, grayscale or an alpha channel.

Bitmap attributes

Bitmap Resources in a package have a number of attributes that you can customize. Most attributes don't have a major purpose and are for library filters, though a minority affects filesize..

Filesize reduction

See the Filesize reduction guidelines page in the Best practices section for our recommendations regarding minizing the filesize of bitmaps embedded into published Substance 3D assets (SBSAR).