opengl - Level Of Detail Surfaces from Multilevel B Splines -

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i read paper scattered data interpolation multilevel b-splines.

consider surface z(x,y), xmin<=x<=xmax, ymin<=y<=ymax. next consider 4x4 grid of "control" points (black): p0 surface covers central cell:

enter image description here

the z value of point (red) on surface (yellow) may approximated weighted sum of values in control points. weights distances control points.

next divide center cell 2x2 cells , add 1 cell border around surface. result control grid p1 (blue). more accurate approximation of z value in red point may found adding distance weighted sum of 4x4 closest control points in p1 initial approximation above.

likewise can repeatedly half size of cells , create new control grids: p2, p3, ...pn. each grid new "level".

each new grid add more detail surface. control grids become increasingly sparse; values differ 0 surface changes abruptly relative sourrounding points.

the result possible storage scheme should able store surface great amount of detail relatively little memory.

how can used in level of detail algorithm?

for each lod tile of surface triangulate using control points level on gpu (preferably using opengl), level being determined how far away camera tile is.

that way hopefully; incredibly detailed surface stored using minimal of memory , viewed different angles , zoomed in/out on quickly.

any ideas or pointers on how this?

you looking view dependent lod selection factor , david luebke's book on lod describes several techniques.

the algorithm use progressive , lod applies classic technique progressive meshes applies yours.

note if use progressive reconstruction algorithm texture mapping rather mesh, have exact same filtering situation perlin noise.


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