Trevor,
As you are aware, I've been working on trying to improve the quality of the POV-Ray rendering in LPub3D. The first step was to implement customized lighting. That resulted in a major improvement, but I was still running into an issue that I felt needed to be fixed: many images had dark gray artifacts on curved surfaces that I couldn't get rid of simply by changing the light definitions.
I think I have finally figured out source of the problem.
When LPub3D invokes L3P, it specifies a camera angle (field of view) of 0.01 degrees (-ca0.01). I assume that you work backward from there to determine the camera distance (-cg0,0,{large number}) in order to end up with a properly-sized image. My guess is that you are using a small field of view and a long distance to minimize apparent distortion caused by different parts of the model being different distances from the camera. I think -ca0.01 is quite a bit of overkill and is leading to the artifacts I mentioned.
I have modified my program that inserts custom lighting to also modify the -ca and -cg parameters. I am currently using a 10-degree FOV and calculating the corrected camera distance. I'm quite pleased with the results. The resulting renders are much closer to the quality I get when using LDView to manually generate the POV file.
Can I suggest that you try larger FOV values to when calling L3P to improve the quality of the resulting render while still minimizing apparent distortion? Perhaps this could be a value set by the user in Preferences.
I've also been working on a way to have LPub3D use LDView for exporting POV files. I've had some moderate success, but it's pretty klugey. Since I figured out the L3P issue, there is no longer the same level of urgency to pursuing this route.
Thank you.
Kevin
As you are aware, I've been working on trying to improve the quality of the POV-Ray rendering in LPub3D. The first step was to implement customized lighting. That resulted in a major improvement, but I was still running into an issue that I felt needed to be fixed: many images had dark gray artifacts on curved surfaces that I couldn't get rid of simply by changing the light definitions.
I think I have finally figured out source of the problem.
When LPub3D invokes L3P, it specifies a camera angle (field of view) of 0.01 degrees (-ca0.01). I assume that you work backward from there to determine the camera distance (-cg0,0,{large number}) in order to end up with a properly-sized image. My guess is that you are using a small field of view and a long distance to minimize apparent distortion caused by different parts of the model being different distances from the camera. I think -ca0.01 is quite a bit of overkill and is leading to the artifacts I mentioned.
I have modified my program that inserts custom lighting to also modify the -ca and -cg parameters. I am currently using a 10-degree FOV and calculating the corrected camera distance. I'm quite pleased with the results. The resulting renders are much closer to the quality I get when using LDView to manually generate the POV file.
Can I suggest that you try larger FOV values to when calling L3P to improve the quality of the resulting render while still minimizing apparent distortion? Perhaps this could be a value set by the user in Preferences.
I've also been working on a way to have LPub3D use LDView for exporting POV files. I've had some moderate success, but it's pretty klugey. Since I figured out the L3P issue, there is no longer the same level of urgency to pursuing this route.
Thank you.
Kevin