What is DXTbmp, and how do I edit flight sim textures?

DXTbmp is a Windows utility for viewing, extracting, editing and re-saving legacy flight-simulator BMP and DDS textures. Built chiefly for FS2004, FSX and compatible Prepar3D content, it separates the colour image from its alpha channel, passes artwork to an external image editor, and restores simulator-compatible compression and mipmaps.

DXTbmp download and Windows installation

You can download the free DXTbmp Windows package from our library. The correct name is DXTbmp; searches for DXT BMP, DXTMP or DTXBMP usually refer to the same texture tool.

1. Download the package. Use the library download above and follow the installation or extraction instructions supplied with it.
2. Run it on Windows. DXTbmp is a Windows utility rather than a native macOS or Linux application. Keep working files in a writable folder outside protected simulator and Program Files directories.
3. Choose an external image editor. DXTbmp handles conversion, alpha channels and texture output, but it is not a full painting application. Configure a raster editor that can preserve exact image dimensions and save a lossless working copy.

Close the simulator before replacing installed textures. Windows may otherwise block the write, or the simulator may continue displaying a cached copy of the old file.

What is a DXT file?

DXT usually describes a family of block-compressed texture formats, not a required .dxt filename extension. DXT1, DXT3 and DXT5 are also known as BC1, BC2 and BC3 respectively.

The compressed image data is commonly stored inside a .dds container or, in older Microsoft flight-simulator add-ons, an extended .bmp container. This is why an FS2004 BMP may not behave like an ordinary Windows bitmap, and why changing a filename from BMP to DDS does not convert the texture.

The extension alone does not reveal everything the model expects. Compression, alpha precision, mipmaps, dimensions and image orientation can all affect whether a texture loads correctly.

What does the DXTbmp texture tool actually do?

DXTbmp acts as a conversion bridge between the simulator texture and a conventional paint editor. It decodes the main colour image, exposes the alpha channel separately and writes the finished texture back in a format older simulators can load.

This protects information that an ordinary image editor may discard. Directly overwriting an extended BMP can remove its DXT compression, alpha channel or mipmaps; unsuitable DDS export settings can cause the same failures.

The alpha channel is a greyscale image stored with the colour texture. Depending on the model's material definition, it may control transparency, reflectivity, specular response or another effect. White does not universally mean “more transparent” or “more reflective”; the aircraft or scenery material determines its meaning.

If an alpha needs changing, follow our practical guidance on classic aircraft alpha channels rather than guessing from the preview alone.

How do you edit a flight simulator texture with DXTbmp?

The safe method is to preserve the source texture, paint a lossless master and use DXTbmp only for extraction and final conversion. This avoids repeated DXT compression and gives you a known-good alpha channel to restore.

1. Back up the complete texture folder. Copy it outside the installed aircraft or scenery package. Some liveries use shared or fallback textures, so overwriting one file can affect several variants.
2. Identify the texture actually used by the model. Confirm the selected livery folder and record the exact filename, extension, pixel dimensions, compression, alpha and mipmap status. In traditional Microsoft aircraft configurations, texture=Red normally refers to a folder named texture.Red.
3. Open the original in DXTbmp. Inspect both the main image and alpha preview. Export or save a separate copy of the original alpha before changing anything.
4. Transfer the colour image to your paint editor. Use DXTbmp's external-editor function or export a lossless intermediary. Keep the original canvas dimensions and orientation; resizing changes how the artwork aligns with the model's UV mapping.
5. Create a layered, lossless master. Keep paint, logos, registrations, panel lines, rivets and weathering on separate layers where possible. Export a flattened copy for DXTbmp instead of repeatedly painting and saving the compressed DXT texture.
6. Change the alpha only when required. It must remain greyscale and match the colour image's dimensions. For a simple colour or marking change, retaining the original alpha is normally safest.
7. Reload the edited colour image. Confirm that the expected alpha is still present. Do not assume an alpha embedded by the external editor has replaced DXTbmp's separate alpha image.
8. Match the original output. Preserve the BMP or DDS container, DXT type and mipmap behaviour unless the add-on's documentation specifies different settings. Avoid manually flipping a texture during an otherwise unchanged DXTbmp round trip.
9. Save and reopen a test copy. Check the saved file's dimensions, format and alpha in DXTbmp before placing it in the simulator.
10. Verify it in the simulator. Inspect the model in daylight and at night, close up and at a distance. Restart older simulators if switching aircraft does not clear the cached texture.

For a worked example using this method, see our step-by-step FS2004 BMP editing workflow.

Do you need a paint kit?

A paint kit is not compulsory, but layered source files make clean repaints much easier. Painting over a flattened, compressed texture can damage baked panel lines and shadows, while fine lettering often develops visible compression blocks.

If no paint kit exists, preserve an untouched extraction as a reference. Build your own layered master above it and perform only one final lossy DXT export.

Which DXTbmp save format should you choose?

Choose the same container and compression as the original unless the add-on documentation explicitly requires a conversion. BMP or DDS is the container; DXT1, DXT3 or DXT5 describes the compression stored within it.

A mistake we see repeatedly is saving correct artwork into the wrong texture format. Glass, fences, propeller discs, polished surfaces and some night textures rely on alpha precision, while removing mipmaps can create shimmer and unstable detail at a distance.

Our comparison of BMP and DDS flight-simulator textures explains containers, compression and mipmaps in more detail.

Why does the edited texture look wrong in the simulator?

Most failed repaints come from editing the wrong file, losing the alpha channel or saving with settings that no longer match the original.

• The aircraft looks flat or excessively shiny: restore the original alpha and test again. Correct colour artwork can still produce the wrong material response.
• Windows, fences or propeller discs are solid: the alpha may be absent, inverted for that material or saved with insufficient precision.
• The whole texture is transparent: the model is interpreting the replacement alpha differently from what you expected. Restore the source alpha before attempting to reverse it.
• Surfaces are white, black or corrupted: check the filename, dimensions, BMP or DDS container and compression. A file that opens as an image is not necessarily valid for that model.
• Nothing changes: confirm the active livery, fallback folders and exact model assignment. Also check simulator caching, write permissions and whether you edited a duplicate installation.
• The result is upside down: DDS orientation has probably been changed during transfer between tools. Return to the backup and let DXTbmp handle the normal conversion rather than adding a manual flip.
• Markings are mirrored on one side: this is generally a model UV-mapping limitation. Some aircraft reuse the same texture area on both fuselage sides.
• Text and registrations look fuzzy: ensure the image was not resized and avoid repeated DXT saves. Small lettering reveals block-compression damage quickly.
• The repaint shimmers at a distance: preserve or regenerate suitable mipmaps. Without them, the simulator must scale the full-resolution texture in real time.

How can you tell if you edited the wrong texture?

Check the aircraft configuration entry and any texture.cfg file inside the livery folder. A fallback can load wings, virtual-cockpit parts or a shared fuselage texture from another directory, so the visible file may not be present in the repaint folder.

If one part refuses to change, apply an obvious temporary test colour to the suspected file and inspect the model. Restore the backup immediately afterwards; renaming several files at random will not change the texture names assigned by the model.

How do you install the finished texture as a separate repaint?

Traditional FS2004, FSX and Prepar3D aircraft normally need a dedicated texture.name folder and a matching aircraft configuration entry. Copying files into the aircraft directory alone does not create a selectable livery.

Duplicate a known-working repaint entry, give it a unique section number and title, then set its texture= value to the new folder suffix. Preserve any required texture.cfg fallback file, and test the repaint without overwriting a stock or working livery.

Can DXTbmp edit MSFS or X-Plane textures?

DXTbmp is intended chiefly for FS2004, FSX and compatible Prepar3D (P3D) content, not general Microsoft Flight Simulator 2020, Microsoft Flight Simulator 2024 or X-Plane material development. It may display some DDS files from those simulators, but opening a file does not prove it can preserve every channel, colour-space rule or compression mode.

MSFS aircraft commonly use PBR materials with separate or channel-packed albedo, normal, metallic, roughness and ambient-occlusion information. X-Plane has its own PNG, DDS, normal-map and material conventions. Passing these maps through a classic colour-plus-alpha workflow can alter data that does not look meaningful as an ordinary image.

Use the aircraft developer's specified tools, material definitions and export settings for PBR or channel-packed textures. DXTbmp remains useful for compatible legacy assets, but it should not be treated as a universal DDS editor.

Can I use DXTbmp with Euro Truck Simulator 2?

An Euro Truck Simulator 2 DDS texture may open in DXTbmp, but DXTbmp is not the recommended general ETS2 modding workflow. The fact that the image is visible does not guarantee that its compression, mipmaps, alpha or packed material channels will survive re-saving.

Use the game or mod author's documented tools and export settings. Preserve the original DDS format, dimensions, mipmap chain and alpha/channel conventions exactly; changing any of them can produce missing textures, incorrect reflections or broken transparency.

For a simple colour texture, DXTbmp can be used for inspection or a carefully matched round trip if you can positively identify every source setting. Keep the untouched original and compare the saved file in game before committing it to a mod.

End-to-end DXTbmp repaint checklist

• Back up the full aircraft, scenery or vehicle texture folder.
• Record the original filename, dimensions, container, DXT compression and mipmap status.
• Export and preserve the original alpha channel separately.
• Paint in a layered, lossless master rather than repeatedly editing the compressed file.
• Flatten a copy at the original dimensions and return it to DXTbmp.
• Match the original BMP or DDS output, compression, orientation and mipmaps.
• Reopen the saved texture and verify its colour image and alpha before installation.
• Install it as a separate test repaint or in a duplicate mod folder.
• Inspect it in the simulator at different distances, lighting conditions and viewing angles.