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I'm using an imported attribute map that's designed to use dithering to create smooth transitions between textures in the final texture map. To this end I left all the blend radii of the land types at -1, and rendered the texture map with anti-aliasing set to 16. The attribute map is the same resolution as the final texture. This mostly works, but wherever there's dithering, a subtle grid or vertical line pattern appears in the final texture. This artifact appears in slightly diferent forms at all the antialiasing radii i've tried (2, 8, 16). Attached is a small piece of the final texture and the attribute map. Anyone have a suggestion how to resolve or avoid the texture looking like this?

Hi botanyothername,

How curious. Can you tell me what the distance is, measured in pixels in the output texture, between the repeating grid/line features? If you use the 'ruler' toolbar button to click and drag between two adjacent lines on the texture map, L3DT will show a message like "(124, 111) to (4345,444), distance = 43874km". The distance in pixels is the difference between the first ordinal in the brackets for the start and end coordinates (e.g. 4345 - 124 = 4221 pixels).

Best regards,
Aaron.

Thanks for replying. In most places the distance is 4, in others, 2.

PS I forgot to mention that all the texture layers involved have a resolution of 1 relative to TX/HF, and the heightfield is also the same resolution as the output texture.

PPS maybe I'll make a small test which just uses two land types, both with a solid color as a texture.

Yup, definitely 4
Here's a 256x256 test, 16 antialiasing, two land types have no appearance, so they just appear as their colors.

Hi botanyothername,

Thanks for the info. I've reproduced the fault; it looks to be in the anti-aliasing. I will post back here when it's fixed (which may be a week or two, due to current commitments). Thanks again for the bug report, and sorry for the inconvenience.

Best regards,
Aaron.

Great

Hi Botanyothername,

Drat, it looks like I've got some work to do here. The previous anti-aliasing routine used a sub-sampling mask to speed up the texture calculation, but this was causing the undesirable patterns in the output. If I omit the masking, the patterns go away and you get nice smooth blended output, but the performance hit is pretty severe. I'll see if I can come up with a better mask and/or more performance optimisations to get some speed back.

Cheers,
Aaron.