📄 trmisc.cpp
字号:
/*----------------------------------------------------------------------------
_ _ _
/\ | | | (_)
/ \ _ __ __| |_ __ ___ _ __ ___ ___ __| |_ __ _
/ /\ \ | '_ \ / _` | '__/ _ \| '_ ` _ \ / _ \/ _` | |/ _` |
/ ____ \| | | | (_| | | | (_) | | | | | | __/ (_| | | (_| |
/_/ \_\_| |_|\__,_|_| \___/|_| |_| |_|\___|\__,_|_|\__,_|
The contents of this file are subject to the Andromedia Public
License Version 1.0 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at http://www.andromedia.com/APL/
Software distributed under the License is distributed on an
"AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
The Original Code is Pueblo client code, released November 4, 1998.
The Initial Developer of the Original Code is Andromedia Incorporated.
Portions created by Andromedia are Copyright (C) 1998 Andromedia
Incorporated. All Rights Reserved.
Andromedia Incorporated 415.365.6700
818 Mission Street - 2nd Floor 415.365.6701 fax
San Francisco, CA 94103
Contributor(s):
--------------------------------------------------------------------------
Chaco team: Dan Greening, Glenn Crocker, Jim Doubek,
Coyote Lussier, Pritham Shetty.
Wrote and designed original codebase.
------------------------------------------------------------------------------
----------------------------------------------------------------------------*/
#include <TrBasic.h>
#include <time.h>
#include <math.h>
#ifdef __STDC__
extern double log2(double);
#else
extern double log2();
#endif
/* globals */
node_t qs[QSIZE]; /* Query structure */
trap_t tr[TRSIZE]; /* Trapezoid structure */
segment_t seg[SEGSIZE]; /* Segment table */
struct global_s global;
/* This is horribly lame, but should work. */
double log2(double x)
{
return (log(x) / 0.69314718);
}
static int choose_idx;
static int permute[SEGSIZE];
/* Generate a random permutation of the segments 1..n */
int generate_random_ordering(int n)
{
#if 0
struct timeval tval;
struct timezone tzone;
#endif
register int i;
int m, st[SEGSIZE], *p;
choose_idx = 1;
#if 0
gettimeofday(&tval, &tzone);
srand48(tval.tv_sec);
#else
srand(time(0));
#endif
for (i = 0; i <= n; i++)
st[i] = i;
p = st;
for (i = 1; i <= n; i++, p++)
{
#if 0
m = lrand48() % (n + 1 - i) + 1;
#else
m = rand() % (n + 1 - i) + 1;
#endif
permute[i] = p[m];
if (m != 1)
p[m] = p[1];
}
return 0;
}
/* Return the next segment in the generated random ordering of all the */
/* segments in S */
int choose_segment()
{
/*
#ifdef DEBUG
fprintf(stderr, "choose_segment: %d\n", permute[choose_idx]);
#endif
return permute[choose_idx++];
*/
#ifdef CHOOSE_MANUAL
int i;
printf("Enter seg: ");
scanf("%d", &i);
return i;
#else
#ifdef DEBUG
TRACE("choose_segment: %d\n", permute[choose_idx]);
#endif
return permute[choose_idx++];
#endif
}
int inserted(int segnum, int whichpt)
{
int n1, n2;
n1 = segnum % global.nseg + 1; /* next seg. */
n2 = (segnum - 1 + global.nseg - 1) % global.nseg + 1; /* prev. */
if (whichpt == FIRSTPT)
return seg[n2].is_inserted;
else
return seg[n1].is_inserted;
}
#ifdef STANDALONE
/* Read in the list of vertices from infile */
int read_segments(FILE *infile)
{
int nseg;
register int i;
memset((void *)seg, 0, sizeof(seg));
i = 1;
nseg = 0;
while (fscanf(infile, "%lf%lf", &seg[i].v0.x, &seg[i].v0.y) == 2)
{
seg[i - 1].v1.x = seg[i].v0.x;
seg[i - 1].v1.y = seg[i].v0.y;
seg[i].is_inserted = FALSE;
i++;
nseg++;
}
seg[nseg].v1.x = seg[1].v0.x;
seg[nseg].v1.y = seg[1].v0.y;
global.nseg = nseg;
return nseg;
}
#endif
/* Get log*n for given n */
int math_logstar_n(int n)
{
register int i;
double v;
for (i = 0, v = (double) n; v >= 1; i++)
v = log2(v);
return (i - 1);
}
int math_N(int n, int h)
{
register int i;
double v;
for (i = 0, v = (int) n; i < h; i++)
v = log2(v);
return (int) ceil((double) 1.0*n/v);
}
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -