ul 2004
ingle of
of root
the leaf
it, is the
or. Leaf
riangles
resents,
nship in
cent leaf
ir own
Lis easy
ip after
ITHM
‚een the
division
Ice from
(5)
1gth (see
2003 for
v)
v)
)
)
Fi)
y;)
(6)
between
idgment
ration’ is
count of
On, while
ment ‘*x/
asure the
1 the two
mplexity
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B5. Istanbul 2004
of calculating Qi(x;,y;) is 100(n) less than that of
calculating distance d,(x;, y; J.
Implementation times
Basic operation
dix; y.) Qi(x;. y;)
Judgement 0 3
[vr 6 2
X/+ 9 1
Jx 1 0
|x] 1 0
Table.1 Comparison of basic operation between d; (xi. v;) and
Qi(x;, y;)
7. CONCLUSION
It is very necessary to improve the efficiency of the algorithm
for mass data processing. This paper discusses the theory and
method of restrained edge mosaic in constructed TIN and
describes our algorithm, the radial spatial division algorithm, in
detail. The following conclusions can be obtained.
(1) This paper proposes radial spatial division method and
relative Formulates based on Qi(x;, y; ), and proves that
this division method can assure that expanded triangle is
in the independent sub-zone theoretically;
(2) Relative algorithm of restrained edge mosaic in
constructed TIN with radial spatial division method based
on Qi(x;, y;) is proposed. The analysis shows that the
frequency count of executing this algorithm’s basic
operation , ‘x/+?, is just one tenth of that of spatial
division algorithm based on distance;
(3) The conception of spatial division tree is also proposed in
this paper. It is shown that this tree will be great benefit
for the reconstruction of triangles and their topology in
region affected by restrained edge after spatial division.
REFERENCE
M. Renslow, 2001. White paper: technology assessment of
remote sensing applications: LIDAR, U. S. Department of
Transportation - National Consortia on Remote Sensing in
Transportation.
httpZ/riker.unm.edu/DASH new/pdf/White?o20Papers/LIDAR.
pdf (accessed 31 Dec. 2002)
Zhu Q. and Chen C., 1998. Quick generation of TIN and is
dynamic updating, Journal of Wuhan Technical University of
Surveying and Mapping, 23(1), pp. 204-207.
Lu Z., Wu C. and Lu X., 1994. A generalized algorithm of
optimal triangulation of simple polygon, ACAT
ELECTRONICA SINCA, Vol. 221 No. 1, pp. 86-89.
Lu C. and Wu C., 1997. Optimal Triangulation of Data Points
Scattered in arbitrary Polygon With Characteristic Constrained,
J. CAD & CG, Vol. 9, No. 4, pp. 302-308.
Li L. and Tan J, 1999. Multiple Diagonal Exchanging
Algorithm for Inserting Constrained Boundary in Constrained
Delaunay Triangulation. CHINESE J. COMPUTERS, Vol. 22,
No. 10, pp. 1114-1118.
Wang J., 2001. Principles for Spatial Information System.
Publishing House of Science, Beijing, pp. 246-248.
Zhou X. and Liu S., 1996. A robust algorithm for constrained
Delaunay triangulation [J], CHINESE J. COMPUTERS, Vol.
19:)No. 8, pp. 615-624.
L. D. Floriani and E. Puppo, 1988. Constrained Delaunay
Triangulation for Multiresolution Surface Description. 9th Inter.
Conf. On Pattern Recognition, Rome, Nov., pp. 566-569.
Qi H. and Liu W., 1996. Qi algorithm for arc-arc topological
relationship built on nodes. ACTA GEODAETICA et
CARTOGRAPHICA SINICA, 25(3), pp. 233-235.
Qi H., 1997. Optimization and improvement for the algorithm
to automatically establish polygon topological relationship.
ACTA GEODAETICA et CARTOGRAPHICA SINICA, 26(3), pp.
254-260.
Qi H., Li D. and Zhu Q., 2003. Time complexity analysis for
two non-angle algorithms to determine the radial spatial
adjacent relationship, Advances in Spatial Analysis and
Decision Making (Zhilin Li, Qiming Zhou and Wolfgang Kainz,
Editors), A.A. Balkema Publishers, Lisse, pp. 45-52.
Guo R., 2001. Spatial Analysis, Higher Education Publishing
House, Beijing.