Hello. Thank you for your detailed steps for reproducing the problem. I repeated them 6 times before I was able to crash 3DCoat in the Debug build under Xcode. The crash happened inside the OpenGL function glReadPixels. The output error message in Xcode is: Terminating due to blacklisting by kernel driver. The source code around the call is correct. I have described the problem to Copilot. Here are some phrases from its answer: This crash is not caused by your code but by Apple's GPU driver on macOS arm64. The "Terminating due to blacklisting by kernel driver" message indicates that the driver detected an unsafe or unsupported OpenGL call sequence and forcibly killed the process. It's a rare, intermittent bug in Apple's OpenGL stack, especially when using glReadPixels under heavy load or with certain pixel formats. Apple has deprecated OpenGL in favor of Metal. The OpenGL implementation is no longer actively maintained, so rare crashes like this persist. glReadPixels stalls the GPU pipeline and copies framebuffer data back to CPU memory. If called at the wrong time, the driver may flag it as unsafe. Since Apple no longer supports OpenGL, you cannot rely on future fixes. For long-term stability on macOS, consider migrating to Metal. The answer indirectly explains why reducing "Desired vertex count" mitigates the problem. Because it reduces the load and thus the likelihood that the graphics driver will flag the operation as unsafe. I have no quick workaround for this problem today. Migrating to Metal is unreal because 3DCoat is developed exclusively under Windows, so all programmers work only with OpenGL and GLSL.

They absolutely are working on it. It's my understanding that the developer (Alexander) who has been working on the Retopo/Modeling tools...with a CAD development background...has been and continues to work on a CAD module which will function very similar to Plasticity, and the module will provide a smooth workflow between Solid Surface and Polygonal/Voxel Modeling environments. In the meantime, you can use some NURBS style tools in the Modeling workspace (in the Sculpt Workspace too, in the CURVES section of the tool panel) and convert those to geometry or NURBS/Solid Surface export.

Pretty cool, but I hope it won't become a resource hog, because 3DC can already be heavy with GPU usage.

Okay. I suspect I may have to do it in Maya. I did try adding a bit more thickness this time, but yeah, the edges/distance is fairly close. Thanks.

yes, try this but if the model is very small or the front and back faces are very close... will be a difficult task

Is this in 2025 or 2026? EDIT: Wait, never mind. I thought it was a totally different Snap option from its drop-down list. You mean to enable Snap to Closest Normal and add Additional Extrusion...?

Hope this help

I don't suppose there's a way of preventing points/geo from automatically snapping to points that are behind it? I'm working on an item of clothing and I've had to add thickness. The problem is, every time I re-add/build the geo on the front, it keeps snapping to the geo behind. You can usually see/feel that snap when directly over a point behind, at which point you have to place it out the way, but sometimes it can still force it to snap through. I've tried unticking Auto Snap, changing the Snap type, and I have backface culling enabled, but nothing seems to work. Thanks

Very exciting. I hope they'll also add the CAD tools at some point. Would be very useful for hard surface stuff. Then I can skip substance and plasticity.

After deleting the coloured faces, it allows me to remove the red seams. It's just strange it doesn't allow me to remove the red seams with faces there.

I think it is safe to drop a little teaser of what's coming. This and the GPU engine has been in development for several years, so it's a pretty big feature addition. Now, you have nodes for working with Sculpt Objects (geometry and voxels)...which allow the user to not only affect the surface, but the entire structure of the object (ie., you could literally use nodes to create things like Swiss Cheese, with holes all the way through the model)...and finally nodes for texturing UV mapped Paint Objects. The big difference between 3DCoat and the competition is that you have nodes for BOTH Sculpting and Texture Painting integrated within the app. ZBrush doesn't have it, nor does Substance Painter. Yes, we know Substance Designer is available to those who are on a Substance subscription, but it's a different experience having the node system completely integrated into your Painting application. Paint Nodes Preview 1.mp4

Great. Thanks. Yeah, the UV Preview is showing broken up UVs. Is there no way of being able to delete them within 3DCoat? I'm still not quite sure how to use that Color Palette. I'm able to pick a colour, but it doesn't really do anything; none of the new polys are the same colour still. Although some added polys on the right side are staying the same colour. Since seeing the UV Preview, I've been able to combine some of the clusters together.

Windows Menu > Panels > UV Preview Every new island or poly w/seams make colors to change If needed, you can create your personal custom palette

I've asked this before, as I went and looked through all of my previous threads, though I'm still non-plussed. The reply I got was from Carlosan who linked a video. I think at the time I just dealt with the issue and couldn't be bothered going through the video due to how long it is. ^^; Apologies. However, going through that video now, to the part about adding Edge Loops and Mark Seams, I'm still not able to figure out how to remove random coloured polygons. They suddenly showed up after taking the mesh into Maya and then bringing it back into 3DCoat. And again, there are no UV islands; I've deleted them. But every new polygon I add now turns a different colour. But I've tried selecting Edge Loops and clicking, holding Ctrl and clicking, pressing Shift and clicking... I've tried Mark Seams and clicking, Clear Seams, Clear Clusters. And I've tried Join UV clusters. The line turns green, but it doesn't combine anything together. Also, is there a way of adding the UV Preview tab back into the Retopo Room? Going to the tab doesn't show any UVs anyway. Thanks

subtracting booleans dont work? also live booleans dont work either

Ah, there it is. Thanks. I guess I wasn't looking hard enough. 

Try this

Hi When I have a bit more time, I'm going to look at setting up my own custom shortcuts in the retopology room. My question is: is it possible to export these setups to load in newer versions of 3DCoat? So if I uninstall/reinstall/install in future, they can be instantly loaded up without having to set them up again? Thanks