"Thumbnails" container
The thumbnail container is part of the TrainzBaseSpec so any asset may specify a thumbnail or preview image. This obviously makes more sense in some cases than in others, but certain circumstances, such as DLS requirements requires some imagery for even sounds. The exact usage of this image may vary depending on the asset kind and the build of Trainz, but the following usages are historically common:
- 32x32 - standard icon representation for display in lists.
- 128x64 - ‘kind traincar’ list icon in Surveyor.
- 512x512 - ‘kind traincar’ preview image in Surveyor.
- 240x180 - Download Station thumbnail image - mandatory, and must be in JPEG format.
- For assets which have no physical appearance (engine-specs, scenery sounds, etc.) content creators tend to make up a stock splash screen sort of self-advertising image.
Note: The Art files directory used in old versions of Trainz should no longer be used- the Thumbnails container replaces and extends this functionality.
Any number of thumbnail entries may be present, however it is recommended that no more than 3 images are used. The specified width and height must match the actual width and height of the image file in pixels.
The DLS thumbnail is a general view of the asset, and may include identifying text or logos.
The minimum for rolling stock is the DLS thumbnail (240x180, JPEG) and the list icon for Surveyor (128x64). The list icon should show the rolling stock asset in a full side-on view, with a transparent background. The image should be centered horizontally, and with the base of the asset (the track level) at the vertical center. This arrangement means that the asset displays correctly in the Surveyor list, in the drivers list in QuickDrive, and also in the consist display that is provided at the bottom of the Surveyor screen. Since a transparent background is required, a 32-bit tga file format (referenced from a .texture.txt file) is recommended.
Supported image formats include:
- 32-bit uncompressed targa (.tga) - this supports an alpha channel
- 24-bit windows bitmap (.bmp)
- JPEG (.jpg)
- Texture file (.texture.txt) - strongly recommended.
When displaying an image, the closest-sized image required by the function (in terms of pixel dimensions) will generally be used in Trainz. The container numbers are simply identifiers and have no meaning in themselves.
thumbnails { 0 { width 32 height 32 image "thumbnail-32.texture" } 1 { width 128 height 64 image "Surveyor-thumb-128.texture" } 2 { width 240 height 180 image "$screenshot$.jpg" } 3 { width 512 height 512 image "Big4DLS_screenshot.jpg" } }