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Andy · 29th May 2017, 05:32 AM

It looks like this is the result to the drawing order. In your first picture, it's correct because the transparent object is drawn last (it's at the end of the hierarchy).

In the second picture, the side at the front is drawn before the rear one. It looks like the views through the edge windows are OK - because the facing side is drawn after the side surfaces.

AC3D doesn't depth-sort polygons for transparency (it's a processor-expensive operation which would slow things down) but generally it's best to put transparent objects at the end of the hierarchy. Many graphics engines will sort polygons for transparency (perhaps by pre-calculating a "transparency map") so it depends where you will be using your output files. Note that sorting doesn't always fix transparency problems. Sometimes objects need to be split up more. Even then there can still be limitations.

29th May 2017, 05:32 AM	#2
Andy Administrator Professional user Join Date: Jun 2003 Posts: 4,565	Re: once again: transparency It looks like this is the result to the drawing order. In your first picture, it's correct because the transparent object is drawn last (it's at the end of the hierarchy). In the second picture, the side at the front is drawn before the rear one. It looks like the views through the edge windows are OK - because the facing side is drawn after the side surfaces. AC3D doesn't depth-sort polygons for transparency (it's a processor-expensive operation which would slow things down) but generally it's best to put transparent objects at the end of the hierarchy. Many graphics engines will sort polygons for transparency (perhaps by pre-calculating a "transparency map") so it depends where you will be using your output files. Note that sorting doesn't always fix transparency problems. Sometimes objects need to be split up more. Even then there can still be limitations.