geomop / bapprox

Python tool for approximate 3d points using Bspline surface

B-Spline Approximator

Python tool for approximate 3d points using Bspline surface.

Requirements

• Python 2.7
• Numpy 1.11
• SciPy 0.18
• GnuPlot 5.0
• Python OCC 0.17

How to Run

python ./src/main.py -f ./conf.yaml

How to Test

PYTHONPATH=$PWD/src py.test tests

bapprox's Issues

Visualization of differences and quad

When quad is defined, then differences between approximation and terrain can't be visualized now, because differences are computed only for cropped part of terrain.

Implement own approximation of terrain

Implement own approximation of terrain data.

Implement fractures

• Get testing data from Jakub.
• Implement reading of fractures from input files.
• Split volume to several volumes using fractures.

Create working version for Windows.

Create binary of something that could be tested at Windows.

Implement faster calculating of points at surface.

Implement faster calculating of points at surface. It is used for computing of differences and it is very slow, when QR or SVD method is used.

The biggest diference

Print the biggest difference between B-Spline surface and original terrain. Add this option to configuration file.

Output rivers to BREP file format

Output approximated rivers (B-Spline curves) to output file format.

Output differences to CSV file

Add option to output differences to CSV text file.

Add filter of SVD method in configuration file

When SVD method is computed, then there is applied simple filter. it si hardcoded now. Add value fo this filter to configuration file.

Fix QR method

Make it possible to use QR method again.

Create volume object and export it to brep file

• Experiment with Intersections of B-Spline and border planes of area.
• Create volume from border area and do boolean operation (intersect) with volume of Surface.
• Set bottom surface (several options).
• Create volume using extrude.
• Create volume using different B-Spline surfaces (different number of knots and poles).
• Output volume to BREP file.
• Test for several fractal borders of area
• Test for several variants of B-Spline surface (different number of poles)
• Test boolean operation between B-Spline surface (different number of poles) and simple plane

Method chol and sparse matrixes

Method method: chol can't be used with combination with dense matrixes (sparse: false) in configuration file. The program is terminated with following error:

Traceback (most recent call last):
  File "./src/main.py", line 51, in <module>
    main(parse_arguments())
  File "./src/main.py", line 29, in main
    terrain.approximate_terrain()
  File "/home/jiri/GitHub/bapprox/src/terrain_data.py", line 302, in approximate_terrain
    {'threshold': threshold})
  File "/home/jiri/GitHub/bapprox/src/approx/terrain.py", line 886, in approx
    return approx_chol(terrain_data, quad, u_knots, v_knots, sparse, conf['threshold'])
  File "/home/jiri/GitHub/bapprox/src/approx/terrain.py", line 820, in approx_chol
    c_mat = bb_mat + r * (bb_norm[0] / a_norm[0]) * a_mat
IndexError: invalid index to scalar variable.

Enable Visualization of Differences

Enable visualization of differences between terrain and b-spline surfaces again.

SVD Method

Make it possible to use SVD method again.

Test variant of sparse matrices

The "dok" format of sparse matrices is used for everything (assembling of matrices, computing) and it is not efficient. Try to use different formats.