mainplist.c

来自「有限元学习研究用源代码(老外的),供科研人员参考」· C语言 代码 · 共 80 行

/* last edit: Ilja Schmelzer -------------- 10-JUN-1994 17:58:40.20	*/
/************************************************************************/
/*                                                                      */
/*  <<< I B G >>> - Intersection - Based Grid generation package 	*/
/*                                                                      */
/*  Version 1.1 by Ilja Schmelzer   [e-mail]       */
/*                                                                      */
/*  to be distributed under IBG license conditions (see "readme.ibg")	*/
/*                                                                      */
/************************************************************************/
/*
	Intersection-Based Grid Generator	Version 1.1

author:	Ilja Schmelzer, IAAS,
	Mohrenst. 39, D-10117 Berlin Germany
	e-mail:	[e-mail]
	Tel:	[phone]
	Fax:	[phone]

This example creates a trivial 2D (4 point) grid and includes three
externally defined additional points.

Two of them are nearly identical. This example shows an interesting
property of the Delaunay algorithm as implemented here - only one of
the two very close points - the second one - will be really part of
the grid. Thus, the resulting grid contains 6 instead of 7 points.

*/

#include <stdio.h>
#include <ibg.h>
#include <ibgd.h>
#include <ibgg.h>
#include <ibgapplication.h>

int main()
{
/* the data of the coarse grid - cuboid */
 ibgFloat x[2] = {-1.0,1.0},
	  y[2] = {-1.0,1.0},
	  z[2] = { 0.0,1.0};
 ibGeometry g0;
 ibGrid	*grid;
 ibgPoint p;
/* ibgNameApplication = "test"; */
 ibgApplicationInit();	/* calls also ibgdInit and ibGridInit */

 g0 = ibgdNew(2);	/* trivial geometry: only one region 2 */

/* here we define the external point list: */

    ibgpX(p)[0] = 0.3;         ibgpX(p)[1] = 0.7;
    ibgpType(p) = ibgSRegion;  ibgpSegment(p) = 2;
    ibgAppendPoint(&ibggExternalPoints, &p);
    ibgpX(p)[0] = 0.7;         ibgpX(p)[1] = 0.3;
    ibgAppendPoint(&ibggExternalPoints, &p);
    ibgpX(p)[0] = 0.70000001;  ibgpX(p)[1] = 0.3;
    ibgAppendPoint(&ibggExternalPoints, &p);

/* remark that this is a dangerous operation. Bad data may lead to
failure of the grid generation. */

/* grid generator call. */
 grid=ibGridGenerate(g0,  	/* geometry description */
	100,	/* approx. point number (for malloc to minimize realloc) */
	2,x,0, 	/* coarse grid data */
	2,y,0,  /* 2 values in x and y data field */
	1,z,0,	/* for the 2D variant only 1 value in z direction */
/* default refinement criteria: */
	ibggDefaultRefineRegion,ibgNULL,
	ibggDefaultRefineFace,ibgNULL,
	ibggDefaultRefineLine,ibgNULL,
	ibggDefaultRefineNode,ibgNULL,
	ibggDefaultRefineEdge,ibgNULL);
/* end of program: */
 ibgNameFile = "test";
 ibgOutput(grid);
 return ibgdQuit();
}