CSG Subtract does not seem to work properly in Constructor 1.0.6
by Thomas -elfprince13- Dickerson · in Constructor · 02/09/2010 (10:46 am) · 4 replies
One of my artists is trying to model a UFO interior, and having a lot of frustrations.
Steps to reproduce bug.
Disable HSR so you can be sure that it isn't interfering (the effect seems to be the same either way).
Construct a large dodecagonal prism with the cylinder tool (begin enough to simulate the volume of a large room). Rotate the prism 12.5 degrees, so that flat sides align with the x and y axises. perform a linear cloning operation, with x, y, and z offsets of zero. scale the x and y axises of the new prism so that there is an offset of 5 to 10 units between their outside surfaces (a nice thick wall). Now perform a CSG subtraction with the inner prism. You should end up with 12 brushes forming the walls of an empty room. Delete the northmost and southmost wall, to provide entrance to the room. Place another object in the room. Now export to dif, and load it up in-engine. Assuming you followed the set of directions, you should see maybe 2/3 of the outer walls, and NONE of the interior. The export process seems to be treating the whole prism as if it is still a single uncut solid, and not rendering the objects placed inside.
Steps to reproduce bug.
Disable HSR so you can be sure that it isn't interfering (the effect seems to be the same either way).
Construct a large dodecagonal prism with the cylinder tool (begin enough to simulate the volume of a large room). Rotate the prism 12.5 degrees, so that flat sides align with the x and y axises. perform a linear cloning operation, with x, y, and z offsets of zero. scale the x and y axises of the new prism so that there is an offset of 5 to 10 units between their outside surfaces (a nice thick wall). Now perform a CSG subtraction with the inner prism. You should end up with 12 brushes forming the walls of an empty room. Delete the northmost and southmost wall, to provide entrance to the room. Place another object in the room. Now export to dif, and load it up in-engine. Assuming you followed the set of directions, you should see maybe 2/3 of the outer walls, and NONE of the interior. The export process seems to be treating the whole prism as if it is still a single uncut solid, and not rendering the objects placed inside.
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C.S. PhD student at Brown University. Project lead for FreeBuild. Administrator, Cemetech tech community. Webmaster for the Village2Village Projects and the Vermont Sustainable Heating Initiative.
#2
02/17/2010 (11:40 pm)
I've done it on objects *way* more complicated than that without problem. I'm not sure why a dodecagonal prism would be any worse.... 
#3
02/18/2010 (12:35 am)
I'm not sure either, I was never able to isolate that issue. It happens quite often on objects with a large number of faces - spheres being the most problematic. Just saying it's a known issue, and you might want to find a work around, there probably won't be a fix coming for it.
#4
02/18/2010 (12:44 am)
I told my artist to construct the room from individual rectangular elements by dragging the vertices together, but it's still odd. I guess this confirms that it happens with round shapes, since my more complex shapes have all been fairly angular still. 
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