As far as I know there is no way to define a background color for thumbnails. When there is a transparent image displayed in a thumbnail the background color of the file list is displayed.
Now when there is an almost white picture with a lot of transparency the whole thumbnail is white.
My current workaround is change the background color for file lists whenever I have to deal with such images. And then switch back to the normal color later.
My suggestion: Having a two color-grid as background for transparent thumbnails is the commonly known way to avoid the above described effect. It's used in most image editing tools.
Here is an example:
http://ghisler.ch/wiki/images/f/f2/Transparent_thumb_grid.png
Link to suggestion in Wiki:
http://ghisler.ch/wiki/index.php/Define_background_color_in_thumbnail_view
Background two color grid for thumbnails
Moderators: Hacker, petermad, Stefan2, white
Background two color grid for thumbnails
Last edited by Lefteous on 2016-03-18, 19:38 UTC, edited 1 time in total.
A good idea in general, but wouldn't this be horribly slow, Windows-GDI programming-wise?
AFAIK TC now simply blends to the file list color.
When having a separate color, you need to paint a separate background for each Thumbnail.
I did some experiments like this some time ago, and it was a painfully slow, especially since Vista+ has questionable GDI performance.
In any case, isn't this something that plug-ins can do, when used for thumbnail/preview?
If I use Imagine to render Thumbnails for pictures files with an alpha part, it already pre-blends to such "checkered" background.
AFAIK TC now simply blends to the file list color.
When having a separate color, you need to paint a separate background for each Thumbnail.
I did some experiments like this some time ago, and it was a painfully slow, especially since Vista+ has questionable GDI performance.
In any case, isn't this something that plug-ins can do, when used for thumbnail/preview?
If I use Imagine to render Thumbnails for pictures files with an alpha part, it already pre-blends to such "checkered" background.
TC plugins: PCREsearch and RegXtract
2MVV
2milo1012
On the other hand changing the chessboard colors would mean all these thumbnails would have to be recreated. So I guess the actual drawing performance should be taken into account.
There can be red, white, black, blue, green single color images with transparency. What color would you choose?Special color may also be useful, not only grid, so it may be customizable. Some images look better on solid colors. Anyway it should be better than using file panel colors (esp. in case of dark panel background).
2milo1012
No I don't think so. Having an alpha-channel these days is state of the art. In the end an alpha-channel has to be drawn only for images which actually have an alpha-channel (that excludes all holiday pictures). Once drawn it can be stored as such in the temporary and persistent cache. This way it becomes an ordinary image.A good idea in general, but wouldn't this be horribly slow, Windows-GDI programming-wise?
On the other hand changing the chessboard colors would mean all these thumbnails would have to be recreated. So I guess the actual drawing performance should be taken into account.
Sure. I guess a better phrasing for the suggestion would have been 'add chessboard background when a thumbnail provider (Lister, Explorer, external program) returns a transparent image)'.n any case, isn't this something that plug-ins can do, when used for thumbnail/preview?