Incorrect offsets/UVs with TEXTURES lump scaling

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Incorrect offsets/UVs with TEXTURES lump scaling

Postby Talon1024 » Sun Oct 28, 2018 12:34 am

If I define textures to be scaled down in the TEXTURES lump, and offset them in a map, the offsets are applied incorrectly in the softplanar and OpenGL renderers. The softpoly renderer seems to work just fine for some reason.

Here's a runnable sample with high-res textures from

Joined: 27 Jun 2016
Github ID: Talon1024
Operating System: Debian-like Linux (Debian, Ubuntu, Mint, etc) 64-bit
Graphics Processor: nVidia with Vulkan support

Re: Incorrect offsets/UVs with TEXTURES lump scaling

Postby Graf Zahl » Wed Oct 31, 2018 5:00 pm

This isn't a bug but an incompletely defined texture.

You have to add a 'worldpanning' instruction to each definition. The reason for this lies deep in the past. When texture scaling was originally implemented it was done with per texel panning, not world-unit panning. Needless to say that isn't the most useful thing, but when a decision had to be made what to use as default, the bad option was chosen.

In clear English: It's the softpoly renderer which is wrong here.
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Graf Zahl
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