PhotoMatch by intersecting ray tracing
-
Hi folks,
I've been thinking about a problem for a while -- if I had a generic solution there are several placed I could apply it.
The issue is using PhotoMatch with photos that just do not have enough straight lines or maybe no lines that can be counted on to be vertical or level. Like making a SketchUp model of the Mystery House at Knott's Berry Farm, or The Santa Cruz Mystery Spot -- or worse, trying to form terrain from photographs.
I assume it would require there to be lots and lots of common points in the photographs that you can match up. But just points, probably not many lines, horizontal or not. Very much the kind of thing that the standard PhotoMatch perspective tools are really bad at.
What I keep coming back to is being able to pick the same point in two or 3 photos and construct lines through the photo image to the camera. The actual 3D point has to line on that ray from the camera center through the point in the PM image, out to infinity. Two or three photos let you find the intersection of the rays.
To play with how the geometry of this works out, to start getting a handle on what the rules of this game have to be, it would be nice to be able to place a PhotoMatch image into a model as a photo texture on a surface, oriented perpendicular to the line to camera for that PM scene. And then, from the viewpoint of that scene, pick a point in the image and run a ruby script that would construct the ray from the camera through that image point.
So has anyone created a script like that, to generate a ray from the camera through a point chosen on a surface or simply through the cursor position?
If no one has done it yet, I'd be willing to hack at it, if someone could toss out hints of what objects and methods would have to be used.
Thanks for any suggestions,
August -
Hi August,
It sounds crazy enough to be interesting (although as you know me, it won't be me who can help you with the scripting details).
But why on (Google) Earth are you posting this in the SU Discussions instead of the Ruby forum?
-
@gaieus said:
... But why on (Google) Earth are you posting this in the SU Discussions instead of the Ruby forum?
Oops. I think I must have mistaken which thread-group I was in.
At your suggestion, and with the indulgence of the rest of the group, I'll repost my question over there (since this was the only response I've gotten in the general area).
August
-
Interesting idea. There definately has to be a better way to do photomatching. I have a lisp script for autocad called Vanishing Point that lets you select a point and then wherever you click next it creates lines that converge back to that point. Its just for creating perspective grids in 2d modelspace, it doesn't do anything that is actually 3d. But I think this sort of flexibility is needed, something that allows the creation of numerous vanishing points and then recognises surfaces where the lines intersect.
Either that or a clone of defunct software Canoma.
-
@august said:
...At your suggestion, and with the indulgence of the rest of the group, I'll repost my question over there (since this was the only response I've gotten in the general area).
August
I could even have moved this thread...
Jon,interesting idea with the lines and vanishing points. In SU you can use guide lines to create a similar effect (I used this technique with fine art - more exatly painter - students to set up perspective scenes with them).
Advertisement