 | | 3D Transformations Architecture Question
|
|
Feedback from the guys who built the viewers (LDGlite, LDView, etc) would be really great on this. I have a project, not Lego, but similar and I'm writing some software for 3D viewing and manipulation of items. The LDraw architecture is a good match (...) (17 years ago, 12-Jul-07, to lugnet.cad)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
Basically you keep 1 copy of the object with its vertices in their original position (local or model space). You take the local to world, world to view, view to projection and projection to viewport matrices and multiply them to get a single (...) (17 years ago, 13-Jul-07, to lugnet.cad)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
(...) Actually, based on what you write after the above, this is a "How do you draw in 3D?" question, which is fairly close to "How do you do 3D?". The implementation details of how 3D gets drawn to the screen tend to answer all your questions. When (...) (17 years ago, 13-Jul-07, to lugnet.cad, FTX)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
(...) Travis, Thanks, but that answer is exactly what I was trying to avoid in this discussion. I understand about creating a transformation matrix, a camera matrix and a projection/perspective matrix. I understand about compositing them all for a (...) (17 years ago, 13-Jul-07, to lugnet.cad, FTX)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
(...) Sorry. I guess I didn't fully understand why you wanted to do the pre-multiplies. Hopefully this reply will be closer to what you are looking for. LDView 1.0 did exactly what you suggest. It calculated the final coordinates for every single (...) (17 years ago, 13-Jul-07, to lugnet.cad, FTX)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
(...) Well thanks for spoiling my day :) I tried orions file and discovered a design flow in my new LD4DStudio renderer. It looks like this: (URL) seems Orion uses the rotation matrix to mirror some parts, this totally F-ups my normals :( And there (...) (17 years ago, 13-Jul-07, to lugnet.cad)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
(...) Thanks Travis, that's *exactly* the info I was looking for. I think I'm going to go ahead and store each object's matrix, as well as the camera and projection matrices, updating any of them only when adjustments are made to the appropriate (...) (17 years ago, 13-Jul-07, to lugnet.cad, FTX)
|
| |
| | Re: 3D Transformations Architecture Question
|
|
(...) Roland, Actually the errors wouldn't be a problem. I wasn't thinking of performing transformations on already-transformed data. I was thinking of performing transformations on the original vertex data, then storing that (as a separate set of (...) (17 years ago, 13-Jul-07, to lugnet.cad)
|
