1 /* 2 ** Author: Eric Veach, July 1994. 3 ** 4 */ 5 6 #ifndef __geom_h_ 7 #define __geom_h_ 8 9 #include "mesh.h" 10 11 #ifdef NO_BRANCH_CONDITIONS 12 /* MIPS architecture has special instructions to evaluate boolean 13 * conditions -- more efficient than branching, IF you can get the 14 * compiler to generate the right instructions (SGI compiler doesn't) 15 */ 16 #define VertEq(u, v) (((u)->s == (v)->s) & ((u)->t == (v)->t)) 17 #define VertLeq(u, v) (((u)->s < (v)->s) | ((u)->s == (v)->s & (u)->t <= (v)->t)) 18 #else 19 #define VertEq(u, v) ((u)->s == (v)->s && (u)->t == (v)->t) 20 #define VertLeq(u, v) (((u)->s < (v)->s) || ((u)->s == (v)->s && (u)->t <= (v)->t)) 21 #endif 22 23 #define EdgeEval(u, v, w) __gl_edgeEval(u, v, w) 24 #define EdgeSign(u, v, w) __gl_edgeSign(u, v, w) 25 26 /* Versions of VertLeq, EdgeSign, EdgeEval with s and t transposed. */ 27 28 #define TransLeq(u, v) (((u)->t < (v)->t) || ((u)->t == (v)->t && (u)->s <= (v)->s)) 29 #define TransEval(u, v, w) __gl_transEval(u, v, w) 30 #define TransSign(u, v, w) __gl_transSign(u, v, w) 31 32 #define EdgeGoesLeft(e) VertLeq((e)->Dst, (e)->Org) 33 #define EdgeGoesRight(e) VertLeq((e)->Org, (e)->Dst) 34 35 #undef ABS 36 #define ABS(x) ((x) < 0 ? -(x) : (x)) 37 #define VertL1dist(u, v) (ABS(u->s - v->s) + ABS(u->t - v->t)) 38 39 #define VertCCW(u, v, w) __gl_vertCCW(u, v, w) 40 41 int __gl_vertLeq(GLUvertex *u, GLUvertex *v); 42 GLdouble __gl_edgeEval(GLUvertex *u, GLUvertex *v, GLUvertex *w); 43 GLdouble __gl_edgeSign(GLUvertex *u, GLUvertex *v, GLUvertex *w); 44 GLdouble __gl_transEval(GLUvertex *u, GLUvertex *v, GLUvertex *w); 45 GLdouble __gl_transSign(GLUvertex *u, GLUvertex *v, GLUvertex *w); 46 int __gl_vertCCW(GLUvertex *u, GLUvertex *v, GLUvertex *w); 47 void __gl_edgeIntersect(GLUvertex *o1, GLUvertex *d1, GLUvertex *o2, GLUvertex *d2, GLUvertex *v); 48 49 #endif 50