.blend file thumbnails doesn't scale up properly on windows #101295

New Issue

Steffen Hartmann · 2022-09-23T12:06:06+02:00

Steffen Hartmann commented

2022-09-23 12:06:06 +02:00

System Information
Operating system: Windows-10-10.0.19044-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 517.40

Blender Version
Broken: version: 3.3.0, branch: master, commit date: 2022-09-06 15:39, hash: 0759f671ce
Worked: never i guess
Short description of error
.blend file thumbnails doesn't scale properly on windows.
2022-09-23 12-01-17.mp4
Sorry for the weird crop but the problem should be clear. The .blend thumbnail stays rather small compared to the others on max zoom/scale level.

Exact steps for others to reproduce the error

Open windows file browser and move to a folder which contains a .blend file.
Use ctrl + mouse wheel to scale folder and file symbols.

.blend thumbnails doesn't scale all the way up.

**System Information** Operating system: Windows-10-10.0.19044-SP0 64 Bits Graphics card: NVIDIA GeForce RTX 3060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 517.40 **Blender Version** Broken: version: 3.3.0, branch: master, commit date: 2022-09-06 15:39, hash: `0759f671ce` Worked: never i guess **Short description of error** .blend file thumbnails doesn't scale properly on windows. [2022-09-23 12-01-17.mp4](https://archive.blender.org/developer/F13559568/2022-09-23_12-01-17.mp4) Sorry for the weird crop but the problem should be clear. The .blend thumbnail stays rather small compared to the others on max zoom/scale level. **Exact steps for others to reproduce the error** 1. Open windows file browser and move to a folder which contains a .blend file. 2. Use ctrl + mouse wheel to scale folder and file symbols. .blend thumbnails doesn't scale all the way up.

Steffen Hartmann commented

2022-09-23 12:06:06 +02:00

Added subscriber: @Harti

Harley Acheson commented

2022-09-23 18:53:29 +02:00

Added subscriber: @Harley

Harley Acheson commented

2022-09-23 18:53:29 +02:00

The thumbnail images that are stored inside the Blend files are 128x128, while the largest thumbnails that Windows supports is 256x256. So it is possible, as shown in the video above, to request thumbnails than are larger than we provide.

However, we might be able to do things a bit better. When GetThumbnail is called we are provided a cx UNIT value for the "maximum thumbnail size, in pixels. The Shell draws the returned bitmap at this size or smaller... The Shell scales the bitmap to render at lower sizes.". There is a further guideline about scaling that says "Windows Vista is responsible for scaling down or down sampling images. If your handler is asked for a larger image than you have available, provide the closest size you have. Do not attempt to dynamically resize your own image."

The passed CX value is only provided for cases where we can choose to select from multiple thumbnails to give the best one.

Instead we currently use that value to scale down our thumbnail if the requested size is less than 128, which is not recommended practice. We could instead just scale up the image to CX value if too small, but leave alone (do not scale down) if larger than requested.

The thumbnail images that are stored inside the Blend files are 128x128, while the largest thumbnails that Windows supports is 256x256. So it is possible, as shown in the video above, to request thumbnails than are larger than we provide. However, we might be able to do things a bit better. When `GetThumbnail` is called we are provided a `cx` UNIT value for the "maximum thumbnail size, in pixels. The Shell draws the returned bitmap at this size or smaller... The Shell scales the bitmap to render at lower sizes.". There is a [further guideline ](https://learn.microsoft.com/en-us/previous-versions/windows/desktop/legacy/cc144115(v=vs.85)) about scaling that says "Windows Vista is responsible for scaling down or down sampling images. If your handler is asked for a larger image than you have available, provide the closest size you have. Do not attempt to dynamically resize your own image." The passed CX value is only provided for cases where we can choose to select from multiple thumbnails to give the best one. Instead we currently use that value to scale **down** our thumbnail if the requested size is *less than* 128, which is not recommended practice. We could instead just scale **up** the image to CX value if too small, but leave alone (do not scale down) if larger than requested.

Harley Acheson commented

2022-09-23 23:33:42 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Harley Acheson self-assigned this 2022-09-23 23:33:42 +02:00

blender-admin commented

2022-09-23 23:49:36 +02:00

This issue was referenced by ff27b68f41

This issue was referenced by ff27b68f41ce511e162d6e561103c522d9507a5f

Harley Acheson commented

2022-09-23 23:51:21 +02:00

Changed status from 'Confirmed' to: 'Resolved'

Harley Acheson closed this issue

2022-09-23 23:51:21 +02:00

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

.blend file thumbnails doesn't scale up properly on windows #101295