db4o-sp Code-SVN

Deleted expression evaluator.

Deleted 3D algorithms - next development focused on 2D (with strategies for extensions to 3D).

Created robust kernel - sign of determinant (EGC with dynamic filter).

Created robust CG algorithms - orientation and isOnLine predicates.

Created robust line intersector - predicate is robust, intersection point computation based on homogeneous coordinates - approximately, but robustly (BigDecimal type with round off to double).

Created geometry and coordinate factories with interfaces.

Test cases (created and successfully passed):
1. Robust kernel
2. CG Algorithms
3. Line intersector

Created Expression evaluator.
From Expression removed method signum. This responsibility moved to evaluator.
Evaluator use dynamic filter:
1. interval arithmetic
2. if result interval has unrecognizable signum, use exact computation.

Created interface for line intersector strategy.
Created concreate strategy of intersector for Generic2D_Coordinates.
Intersect of point with line OK
Intersect of line with line - predicate part OK, constructive part under construction.

I have created robust core of spatial extension. Contains evaluation of expression by exact and/or approximate computation. Support expression witch contains operations +,-,*,/ and sqrt. Support exact computation of sign of expression with dynamic filter for increase of speed.
Exact computation is based on BigDecimal with unlimited context - BigDecimalAdapter,
Approximate computation is based on RealInterval with fast context (type from JInterval library) - RealIntervalAdapter. Simply tested on sign of determinant.

Added basic CGAlgorithms orientation and incircle for 2D and 3D (based on operation +,-, * only). Its implementation based on robust Expression of course. Strategy design pattern is used for algorithms. Simply tested on 2D and 3D coordinates.

Support basic referencing (ISO 19111) from library JScience. Created general 2D and 3D coordinates and crs. Referencsing from JScience supports conversions, crs, cs and coordinates.

Removed class EGCDeterminant because of foundation of Expression.

Progress on EGC.
Expr - precision driven development on Real from JScience - failed.
Real - failed - not exact
Rational - failed - 0/x - inverse problem in LUDecomposition.
BigDecimal - ok, but problem with zero - robust problem possibility. (B(E) = 0E-100 - static).
In next revision will be deleted method for failed solutions,

GeometryFactory class created.
GeometryFactoryTest class initialized.

Added doc directory for javadoc.

Comment for r11: Added Generic and default CRS and Coordinates for 2D and 3D Cartesian place.

Created basic set of API classes.
Implemented algorithm for exact determination of sign of determinant with use of dynamic filter based on interval arithmetic.
Used libraries JScience and JInterval.

Just begin.

Creating and initialization of project completed.
Created KnowledgeTest.java file.