scale relative to camera
Hello, I have a situation where I would like an object to remain the same size relative to the camera. Think in terms of pixel width for example. I managed to accomplish this through ICE by using the distance between the camera and the object to manage the scale for the object. The problem is this. If the object is in the center of the viewport and I move the camera towards or away from the object, its perfect. The scale remains constant relative to the viewport. But if the object is on the periphery of the viewport, it is slightly larger than in the center of the viewport. The object scale still remains relative if the camera moves, the problem is that the scale is different than in the center. I assume this has something to do with forced perspective having an affect on the scaling? Has anyone tried this before? I haven't a clue how to correct this at the moment. Any ideas would be appreciated. -- Joey Ponthieux LaRC Information Technology Enhanced Services (LITES) Mymic Technical Services NASA Langley Research Center __ Opinions stated here-in are strictly those of the author and do not represent the opinions of NASA or any other party.
Re: scale relative to camera
You'll have to adjust for the shift from the camera center. Instead of using the camera-to-object distance as your multiplier, you should use (I haven't tried it, so hopefully the math is right): (cosine alpha) * (distance camera-to-object) alpha is the angle between your camera-to-object-vector and your camera-to-camerainterest-vector On Wed, Sep 4, 2013 at 5:25 PM, Ponthieux, Joseph G. (LARC-E1A)[LITES] j.ponthi...@nasa.gov wrote: Hello, ** ** I have a situation where I would like an object to remain the same size relative to the camera. Think in terms of “pixel width” for example. I managed to accomplish this through ICE by using the distance between the camera and the object to manage the scale for the object. ** ** The problem is this. If the object is in the center of the viewport and I move the camera towards or away from the object, its perfect. The scale remains constant relative to the viewport. But if the object is on the periphery of the viewport, it is slightly larger than in the center of the viewport. The object scale still remains relative if the camera moves, the problem is that the scale is different than in the center. I assume this has something to do with forced perspective having an affect on the scaling? ** ** Has anyone tried this before? I haven’t a clue how to correct this at the moment. Any ideas would be appreciated. ** ** -- Joey Ponthieux LaRC Information Technology Enhanced Services (LITES) Mymic Technical Services NASA Langley Research Center __ Opinions stated here-in are strictly those of the author and do not represent the opinions of NASA or any other party. ** **
RE: scale relative to camera
Christian, Indeed, this did the trick nicely! Thanks! -- Joey Ponthieux LaRC Information Technology Enhanced Services (LITES) Mymic Technical Services NASA Langley Research Center __ Opinions stated here-in are strictly those of the author and do not represent the opinions of NASA or any other party. From: softimage-boun...@listproc.autodesk.com [mailto:softimage-boun...@listproc.autodesk.com] On Behalf Of Christian Gotzinger Sent: Wednesday, September 04, 2013 12:15 PM To: softimage@listproc.autodesk.com Subject: Re: scale relative to camera You'll have to adjust for the shift from the camera center. Instead of using the camera-to-object distance as your multiplier, you should use (I haven't tried it, so hopefully the math is right): (cosine alpha) * (distance camera-to-object) alpha is the angle between your camera-to-object-vector and your camera-to-camerainterest-vector On Wed, Sep 4, 2013 at 5:25 PM, Ponthieux, Joseph G. (LARC-E1A)[LITES] j.ponthi...@nasa.govmailto:j.ponthi...@nasa.gov wrote: Hello, I have a situation where I would like an object to remain the same size relative to the camera. Think in terms of pixel width for example. I managed to accomplish this through ICE by using the distance between the camera and the object to manage the scale for the object. The problem is this. If the object is in the center of the viewport and I move the camera towards or away from the object, its perfect. The scale remains constant relative to the viewport. But if the object is on the periphery of the viewport, it is slightly larger than in the center of the viewport. The object scale still remains relative if the camera moves, the problem is that the scale is different than in the center. I assume this has something to do with forced perspective having an affect on the scaling? Has anyone tried this before? I haven't a clue how to correct this at the moment. Any ideas would be appreciated. -- Joey Ponthieux LaRC Information Technology Enhanced Services (LITES) Mymic Technical Services NASA Langley Research Center __ Opinions stated here-in are strictly those of the author and do not represent the opinions of NASA or any other party.
