CompuServe Thread

SA3D connundrum

9 messages in this thread
#24416From: Patrick Di JustoNov 12, 1989 8:42 PM
Awright, here goes. I want to use SA3D and Interfont to create an animation of a spotlight moving back and forth over a movie marquee. I've gotten everything working except the spotlight. How can I get the spotlight beam to move without moving the "target"??? Everytime I move the target, the image changes drastically. I can't figure this one out. If anyone has any ideas I'd be glas to hear them.
#24457From: SyndesisNov 13, 1989 5:57 PM
Hmm. This would be easier in VideoScape. 🙂 Do you want to see the beam, as if it were obscured by dust? Or do you simply want to change the lighting across the face of the letters, as if a spotlight were shining on it? In the first case, it's darn near impossible. You might try big triangles of glass in a cone shape. For the light, you could put a lamp in a cone of triangles, to cast a beam-like shadow, or you could mask the beam through a round hole, behind the observer, so you don't see the triangles that shape the light. To easily make a sheet with a round hole in it, make a cylinder, select only the top, expand it a bit, then move it down to the same plane as the bottom of the cylinder, and continue to expand it into a large washer-like object. BTW, my next-to-appear Spotlight column in Compute's Amiga Resource magazine is about Sculpt 4D, along with a feature on the past, present and future of Amiga 3D.
#24499From: Patrick Di JustoNov 14, 1989 12:32 PM
Use the RM Function to read these messages.
#24552From: John PendergrassNov 15, 1989 3:29 PM
Patrick, I just finished a project that had (I think) exactly the effect you want. Try this: you have your titling in place, and don't move the target or observer. Put a 100 or so watt lamp some distance away. Create a motion path that goes back and forth in front of the letters (or whereever you want it to go) Create a lamp – small 1-10 watts, depending on how much effect you want. Name the lamp as a child of the motion path. Now, when you trace the images, the dim light will move over the scene, highlighting what it is near. You will need the other lamp in the scene as well, or else the exposure will over compensate for the dim lamp. Worked great for me. Gave me a nice circular light that panned over the scene.
#24603From: Patrick Di JustoNov 16, 1989 7:24 AM
They say that great minds think alike: we've proved that it's true. Last night I came up with that very idea. I have the light moving in a figure 8, tilted about 30 degre off horizontal. It is chugging away as we speak. I'll let you know how it comes out!
#24602From: SyndesisNov 16, 1989 12:56 AM
Lamps are invisible, right? So you could move a lamp very near the object, and it would light up as if a firefly were passing by… but it wouldn't look like a spotlight. It wouldn't have crisp edges unless you masked it somehow.
#24604From: Patrick Di JustoNov 16, 1989 7:25 AM
Read my last message, in which John and I discuss moving lamps. I think we've hit on the proper solution…
#24618From: John PendergrassNov 16, 1989 4:04 PM
John, I also thought that the borders would be very diffuse, but they did turn out very crisp. (with dither at about 50% anyway) I think that the additional lamp in the pic that shed a dim global light on the scene gave the illusion of a pretty crisp spotlight as well… BTW, I did all my lettering with InterFont. Still great stuff. (now, when did you say that Interfont would autotrace around standard fonts?) –jp–
#24672From: Louis MarkoyaNov 17, 1989 5:34 PM
THere is an EXCELLENT PD font autotracer called Fontmaster….outputs Sculpt format and is easy to use….look for it…………..Louis