How do I open and edit FS2004 aircraft texture BMPs?

DXTbmp opens FS2004 (FS9) extended BMP textures that ordinary paint programs often mishandle. Use it to send or export the RGB colour image to an external editor, then reload the edit. Keep the original alpha channel, canvas size and filename, and save through DXTbmp in a compatible Extended Bitmap format.

Which FS2004 texture folder should I edit?

Edit the texture folder selected by the aircraft’s active [fltsim.x] entry. In aircraft.cfg, texture=BA points to the texture.BA folder inside that aircraft’s directory; an empty texture= value normally selects the plain texture folder.

Back up the complete folder before making changes. If you are creating a separate livery, copy the appropriate texture folder and add a matching [fltsim.x] entry rather than replacing the original. Our layered FS2004 repaint and aircraft.cfg workflow covers that larger job.

FS2004 texture sheets often look fragmented, mirrored or upside down in places. That is normal: the aircraft model’s UV mapping determines where each area appears. Do not rearrange the sheet to make it look more logical.

How do I use DXTbmp to edit an FS2004 texture?

Use DXTbmp to decode and rebuild the simulator texture while a conventional graphics editor handles the painting. If it is not installed, the DXTbmp extended-bitmap utility is available in our downloads library.

1. Back up the source files. Copy the active texture folder and, if you will alter livery entries, aircraft.cfg. Close FS2004 before overwriting a loaded texture.
2. Open the original BMP in DXTbmp. Note the format DXTbmp reports, such as DXT1, DXT3 or 32-bit 888-8. Also record the pixel dimensions and whether the source contains mipmaps.
3. Inspect the separate alpha image. If an alpha channel is present, leave it loaded and export a greyscale backup if possible. An opaque DXT1 texture may legitimately have no useful alpha.
4. Send or export the RGB colour image. Use DXTbmp’s editor hand-off where configured, or export the colour image in a lossless format and open it in your paint program. DXTbmp, not the paint program, should write the final simulator BMP.
5. Edit the colour image. Keep the exact canvas dimensions and pixel positions. Do not crop, resize, rotate or resample the sheet, and save a layered master in the editor’s own format.
6. Reload or import the edited RGB image. After saving in the external editor, use DXTbmp’s reload-after-edit function or import the replacement colour image. Confirm that the new artwork appears in DXTbmp’s main preview.
7. Verify or import the alpha separately. Retain the alpha still shown in DXTbmp unless the material effect is being changed deliberately. If it was lost, import the backed-up greyscale alpha at exactly the same dimensions.
8. Save as an Extended Bitmap. Select the original FS9-compatible format and mipmap setting, then save under the exact original filename. Do not choose an ordinary Windows BMP save option in the external editor.
9. Force FS2004 to reload the result. Select another aircraft and return to the edited one. If the old paint remains, close FS2004 completely and restart it to clear the loaded texture from memory.

Changing aircraft texture colours (色変化)

For a colour change or 色変化, recolour only the RGB image while preserving surface detail, mapped edges and the original canvas dimensions. The safest approach is to make selections or masks around the painted panels and apply colour adjustments on separate layers.

• Preserve panel detail: use hue, colour or blended adjustment layers that retain the underlying light, shadow, rivets, panel lines and weathering. A flat opaque fill often makes the repaint look unfinished.
• Respect mapped boundaries: keep paint within the intended panel or fuselage area. Leave a small amount of colour bleed beyond mapped edges where the original texture does so, as this can prevent pale seams on the model.
• Expect mirrored parts: some models map both sides to the same pixels. A registration or logo placed there may appear reversed or duplicated in FS2004, and the bitmap alone cannot change that mapping.
• Keep the canvas unchanged: retain the original width, height and orientation. Even a small crop or rescale moves every marking away from the model’s UV coordinates.
• Leave alpha alone: ordinary paint colour changes belong in the RGB image. Alter the alpha only when you intentionally want to change reflection, shine or transparency.

How do I preserve the FS2004 alpha channel?

Keep the original alpha data because the aircraft model’s material determines how FS2004 uses it. On one texture it may govern reflectivity; on another it may control transparency or opacity. A solid black, white or missing replacement can make the aircraft appear excessively shiny, dull, dark or partly invisible.

DXTbmp displays alpha as a separate greyscale image. Editing and reloading only the RGB colour image should leave that alpha in place, but always inspect the alpha pane before saving. Do not assume that an apparently opaque exterior texture has no material use for its alpha.

If the effect itself needs changing, export and edit the alpha independently without resizing it. Our guide to FS2004 reflectivity and transparency alpha editing explains that separate process.

Which DXTbmp save format should I use for FS2004?

Retain the format reported for the original texture unless there is a specific reason to change it. This preserves the expected alpha behaviour and avoids unnecessary texture-memory use.

Converting a DXT3 texture to DXT1 destroys its graduated alpha even if the RGB image looks unchanged. If DXTbmp identifies another source format, preserve it unless the aircraft’s documentation gives a reason to convert it.

Should FS2004 aircraft textures have mipmaps?

Retain the source texture’s mipmap setting by default. Mipmaps store progressively smaller versions of the image and usually reduce shimmering or crawling detail as an exterior aircraft moves farther from the camera.

For a newly created exterior texture, generate mipmaps from the finished full-resolution master rather than repeatedly compressing edited copies. Fine lettering can soften in lower mip levels, but omitting mipmaps often makes distant markings flicker. Do not add or remove them merely to reduce the BMP’s file size.

Why is the edited texture black, missing or unchanged?

Check the active folder, FS2004’s texture cache, the saved bitmap type and the alpha channel in that order. These tests separate four faults that can otherwise look similar.

1. Confirm the active texture folder and filename. Read the selected aircraft’s texture= line and verify that the edited BMP is in that exact folder. Check for hidden extensions that have produced a name ending in .bmp.bmp. Restarting FS2004 will not help if the wrong livery folder was edited.
2. Eliminate FS2004 texture caching. If the aircraft still shows the old paint, switch to another aircraft and back again. For a decisive check, exit FS2004 completely and relaunch it. A correct edit that appears only after restarting was being masked by cached texture data.
3. Reopen the final file in DXTbmp. Compare its reported type with the original. If an external editor saved an ordinary Windows BMP instead of an FS9 extended BMP, its alpha may be gone and FS2004 may not load it as intended. Import the edited RGB image into DXTbmp again and save it with the Extended Bitmap option.
4. Compare the alpha with the backup. Black, invisible, abnormally reflective or unexpectedly dull surfaces point to a missing, solid or incompatible alpha channel. Restore the original alpha and its original format; do not use DXT1 if the effect depends on graduated grey values.
5. Check dimensions and mipmaps. Misplaced markings indicate that the canvas was cropped, resized or shifted. Shimmering at a distance usually means suitable mipmaps are missing, while blurred lower-detail markings may come from poorly generated mip levels.