Questions tagged [3d]
The 3d tag has no usage guidance.
29
questions
0
votes
1answer
87 views
Point cloud to height map in C++
With the increased popularity of 3D imaging and scanning I thought it would be easy to transform a xyz point cloud into a Height Map (xy matrix of z points), but after a couple of hours searching I ...
0
votes
0answers
32 views
Parameter sampling from a 3D isosurface in R
Before we start, a small disclaimer: I am not a computer scientist, and the field of isosurfaces is new to me, so hopefully, the question is phrased clearly:) Otherwise, let me know, and I will (try ...
1
vote
1answer
201 views
3D laplacian operator
I have been unable to find the equivalent of the 5-point stencil finite differences for the Laplacian operator.
In 2 dimensions for me it is clear that, using the finite difference method: $$
\nabla_{...
2
votes
1answer
91 views
Going From Blender Structure defined by triangles to full 3D mesh (Using GMSH?)
I currently have created a model airplane in Blender by drawing a closed volume with triangular planes. I want to do a FEM calculation on this object, meaning I need a fine 3D tetrahedral mesh of this ...
-1
votes
1answer
106 views
How to get free energy surface of a 3d Ising Spin system using Monte Carlo simulation?
I am doing a Monte Carlo Simulation of the properties of a 3D Ising Spin system. I want to get the free energy surface of the spin system from the simulation. It is a magnetization vs free energy ...
0
votes
1answer
165 views
Why the magnetisation shows abrupt behaviour for this 3D ising spin system
I am trying to simulate a 3D Ising spin system (+1 & -1) using Monte Carlo Metropolis Algorithm. I want to get different physical quantities from this simulation like magnetization, Average Energy,...
3
votes
2answers
134 views
Find shortest path around a cylinder represented by 3d triangular mesh
Suppose I have a 3d triangular mesh with the topology of a finite cylinder. Let $C$ be a vertex on that mesh.
How can I find the shortest path from $C$ to itself that goes around the cylinder? By ...
2
votes
1answer
47 views
Algorithm to determine flat surfaces and camera orientation without specialized hardware
Modern augmented reality platforms such as Google's ARCore and Apple's ARKit seem to only operate on mobile devices, I'm guessing, because their underlying algorithms require specialized hardware that ...
4
votes
0answers
60 views
How to implement register blocking for 3D finite-difference stencil computations
I am in need to optimize the performance of the 3D solver that integrates a system of equations for seismic wave propagation.
Unsurprisingly, the function that implements the finite-difference stencil ...
4
votes
2answers
568 views
3D contour mesh computation
I have the value of a function in three dimensions, $f(x, y, z)$, which varies smoothly.
I would like to compute a 3D mesh where $f(x, y, z)$ has a particular value.
Are there algorithms to do this? ...
0
votes
1answer
62 views
On which software can I simulate landmass collisions?
I need to be able to set the properties of the materials (density, size etc) and see what happens according to laws in Physics when landmasses collide each others, with or without bodies of water, ...
1
vote
1answer
740 views
Iterative camera calibration - No convergence
I am trying to implement the algorithm from the research paper "Accurate Camera Calibration using Iterative Refinement of Control Points" from Datta et al.
Running many iterations does not show a ...
0
votes
1answer
218 views
Linear Least-Squares Point-to-Plane ICP degenerative case
I'm trying to implement Linear Least-Squares Optimization for Point-to-Plane ICP Surface Registration
Paper describes linear approximation for point to plane distance for rigid ICP. This approach is ...
5
votes
2answers
2k views
Algorithms to extract trajectory lines out of 3D point clouds
I am looking for different approaches to extract 3D polylines out of Point Clouds.
We are able to create these point clouds out of different data sources of real world surveys (LIDAR, RADAR, etc...) ...
0
votes
2answers
467 views
What would be a good, fast, way to interpolate a point in 3D space
So I have a 3D mesh made of elements with eight nodes, 12 sides per cell, and in the course of my simulations, I would have to interpolate data from those nodes onto a point inside the cell with a ...
1
vote
1answer
132 views
How to handle 2D and 3D models efficiently
My coworkers and I have developed a c++ library implementing a "3D Geological Model" class. Goal of this library is to provide a data structure that is used in computational codes (such as Finite ...
1
vote
2answers
160 views
Data cloning into 3D matrix
I am working with MATLAB, and I would have the following problem. I have the following matrix of random numbers rand(200,200)
and I need to create a 3D matrix ...
1
vote
1answer
552 views
3-dimensional plotting with nonuniform grids
I have 3 variables I am considering: time (t), 1-dimensional space (x), and intensity (I). I would like to plot the intensity in the z-axis as a function of t and x (the latter two variables would ...
4
votes
2answers
565 views
Lid-driven Cavity benchmark in 3D. Classical paper to compare
I'm looking for a benchmark for the lid-driven cavity problem in 3D to compare the results of my code.
In 2D I used:
U. K. N. G. Ghia, K. N. Ghia and C. T. Shin (1982)
High-Re solutions for ...
2
votes
2answers
737 views
Fitting orthogonal planes to a point set
I have a set of 3d points to which I want to fit two planes. I know the assignment of points to the planes so I don't need any RANSAC or similar.
Currently, I'm using a PCA-based approach to fit two ...
2
votes
2answers
164 views
Is model-view-controller useful pattern useful to build scientific simulation programs?
I work with scientific simulation, but what I like the most in programming is creating graphical user interfaces and 2D or 3D outputs to visualize the evolution of the simulations. I know most input ...
1
vote
1answer
680 views
Iterative Closest Point Algorithm
I am currently working on an iterative closest point algorithm (in C++, see here).
I understand the basic premise of an ICP algorithm. You have two point clouds (a target and a reference) and you ...
1
vote
0answers
117 views
Reducing oscillations a 3D Alternating direction explicit scheme for the diffusion equation?
Hi I have made a 3D alternating direction explicit scheme for solving the diffusion equation, which will eventually replace a FTCS scheme in model of bubble dynamics in tissue. I have been testing it ...
0
votes
2answers
517 views
Rotate 2D shape around origin in a 3D space
I have a 2D square ABCD in a 3D space, with side length 2s, that is represented by four vectors (one for each vertex) and a fifth vector ...
2
votes
1answer
5k views
Plot a surface from data sets in MATLAB
I tried to plot a surface in MATLAB but, since it is the first time I had to do something like this, I need a confirmation on the process I followed because it is important for my project to plot the ...
2
votes
1answer
91 views
Best place to start learning Stereophotogrammetry
Firstly I would like to achieve a final goal as can be found in the links below:
Link 1
Link 2
Now I started doing a little bit of research and found that Stereophotogrammetry is the field I should ...
1
vote
1answer
171 views
Simulate aerodynamics of a general shape object
I'm trying to code a simple physics simulator in C++ but I'm stuck on the air resistance issue. Surfing the Internet I only find a drag coefficient for very basical area shapes when the air is ...
3
votes
2answers
4k views
Octave 3D mesh, data from file
I have a big file with 3 columns: density, dimension, value.
example:
10 0.3 200
10 0.4 300
20 0.3 250
20 0.4 320
...
I am trying to draw a 3d plot - ...
3
votes
2answers
899 views
Simulating laminar fluid flow in microfluidics device
I just started working in a lab that is trying to design microfluidics devices to trap and manipulate colonies of E. coli cells. Given a 3D model of such a device created in Autodesk Inventor (or a ...
