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Edge lines when moving

Hi,
I am new to shapespark and this community,
and I am amazed by the program and the support here.

but I am struggling with edge lines when moving the camera
the lines are not there before the bake, but after any baking settings
the vertical and horizontal lines form the walls and objects are visible.
especially in the distance and when moving.

btw. I am using the sketchup, and I tried every solution, group objects, components, single mesh…

also I realised that when I scale down the scene in sketchup, the lines are less visible,
but then the baked lightning is very poor.

you can see the example here, especially on the columns and doors:
https://avatarstudio.shapespark.com/muzej-1/

what are your experiences with this?

Some of these flickering lines are unavoidable, especially straight narrow gaps are problematic in architectural scenes, because when viewed from larger distance some pixels centers will hit the gap and will be dark, and some will miss the gap and will be lighter. When the camera moves, the position where the gap is hit changes, which causes the flickering. When the camera stops moving, a more sophisticated anti-aliasing is used, which involves rendering several frames with tiny camera position offsets and such antialisting hides the flickering.

But some of the flickering lines in your scene are hard for us to explain, because they are present in places where there is no gap. After testing several settings we suspect there could be a bug that is causing this, but we will investigate further and confirm this.

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Thanks, @jan, I appreciate your help because my project depends on it.

if you want, I can share the scene with you.

p.s. I started using shapespark one month ago
and I didn’t experience this problem on the previous version ( 1.17.0)
also, after the update, I think the scene is much brighter on default settings.

hi @jan, is there any news regarding the lines?
because it is driving me crazy, I have tried every solution, and the lines are still there.

Sorry for the troubles. We are working on this, but so far don’t have anything that provides substantially better results. We still have couple of ideas to try.

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Hi @jan

I have made numerous tests regarding the lines,
and it seems that everything depends on the angle of the object.
even if I rotate the whole scene, the lines appear on the different edges.

and it is more pronounced on distant objects.

here is one of my test scene:
https://avatarstudio.shapespark.com/numbers/

some edges are really annoying, and others are barely visible.
and if I rotate the scene, say 90 degrees, the lines show on different edges

I really hope that you find the solution for this

feel free to include me in your tests.

Hi @Tom
It seems to me that the surfaces of the walls and ceilings - vertexs are not welded.
Can you place the SketchUp file to download and check in 3D Max? (I don’t use SketchUp but I can import it into 3D MAX)

Here is what we have found:

Doted lines that are visible from large distance and from an angle, are caused by WebGL native antialiasing (MSAA). A thing that we didn’t realize before is that MSAA samples triangles in locations that can be outside of the triangles borders, which can cause lightmap uv island borders to be crossed. Shapespark fills each uv island with a one pixel margin, but such margin turns out to be not enough. When a surface is viewed at angle and large distance MSAA can cause uv island borders to be crossed by multiple pixels.

We still don’t have a good solution. A mechanism that is usually used to address this issue: centroid sampling is not available in WebGL, but we are experimenting with other approaches.

If anyone is interested in more detailed explanation of this issue take a look at ‘Center or Centroid? (Or When Shaders Attack!)’ article in this pdf: https://www.opengl.org/img/uploads/pipeline/pipeline_003.pdf

@wojtek, could this be the same cause of the issue I was talking about with anti aliasing in Oculus Quest headset?

@Random, I don’t think so. The issue you describe in the other post looks like a general aliasing in VR issue - see my answer here: VR Headset - Oculus Quest