inside.c
c99f2e455a51grid_srcplane_conversion

inside.c
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			#include<stdio.h>
			#include<math.h>
			#include<fonction.h>
			#include<constant.h>
			#include<dimension.h>
			#include<structure.h>


			/****************************************************************/
			/* nom: inside */
			/* auteur: Jean-Paul Kneib */
			/* date: 10/02/92 */
			/* place: Toulouse */
			/****************************************************************
			* Return 1 if P is inside the triangle T, 0 otherwise.
			* Parameters :
			* - P : a point
			* - T : a triplet of points.
			*/
			int inside(struct point P, struct triplet T)
			{
			double s, s1, s2, d;

			d = determinant(&T->a, &T->b, &T->c);
			s = determinant(&T->a, &T->b, P) * d;
			s1 = determinant(&T->b, &T->c, P) * d;
			s2 = determinant(&T->c, &T->a, P) * d;

			return((s > 0.) && (s1 > 0.) && (s2 > 0.));
			}

			/****************************************************************
			* Return 1 if P is inside the triangle T or on its border, 0 otherwise.
			* Parameters :
			* - P : a point
			* - T : a triplet of points.
			*/
			int insidebord(struct point P, struct triplet T)
			{
			double s, s1, s2, d;

			d = determinant(&T->a, &T->b, &T->c);
			s = determinant(&T->a, &T->b, P) * d;
			s1 = determinant(&T->b, &T->c, P) * d;
			s2 = determinant(&T->c, &T->a, P) * d;

			return((s >= 0.) && (s1 >= 0.) && (s2 >= 0.));
			}