41 lines
2.5 KiB
C
41 lines
2.5 KiB
C
|
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
||
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
||
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
||
|
|
│ Copyright 2020 Justine Alexandra Roberts Tunney │
|
||
|
|
│ │
|
||
|
|
│ This program is free software; you can redistribute it and/or modify │
|
||
|
|
│ it under the terms of the GNU General Public License as published by │
|
||
|
|
│ the Free Software Foundation; version 2 of the License. │
|
||
|
|
│ │
|
||
|
|
│ This program is distributed in the hope that it will be useful, but │
|
||
|
|
│ WITHOUT ANY WARRANTY; without even the implied warranty of │
|
||
|
|
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
|
||
|
|
│ General Public License for more details. │
|
||
|
|
│ │
|
||
|
|
│ You should have received a copy of the GNU General Public License │
|
||
|
|
│ along with this program; if not, write to the Free Software │
|
||
|
|
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
|
||
|
|
│ 02110-1301 USA │
|
||
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
||
|
|
#include "libc/mem/mem.h"
|
||
|
|
#include "tool/viz/lib/convolution.h"
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Creates padded array of array indices.
|
||
|
|
*
|
||
|
|
* This can be used to virtualize the memory of a matrix in one
|
||
|
|
* dimension, to make it easy to avoid out-of-bounds access.
|
||
|
|
*
|
||
|
|
* @return value needs free(retval - leftpad)
|
||
|
|
*/
|
||
|
|
unsigned *convoindex(unsigned leftpad, unsigned n, unsigned rightpad) {
|
||
|
|
unsigned i, j, *p;
|
||
|
|
if ((p = malloc(sizeof(unsigned) * (leftpad + n + rightpad)))) {
|
||
|
|
i = 0;
|
||
|
|
for (j = 0; j < leftpad; ++j) p[i++] = 0;
|
||
|
|
for (j = 0; j < n; ++j) p[i++] = j;
|
||
|
|
for (j = 0; j < rightpad; ++j) p[i++] = n - 1;
|
||
|
|
}
|
||
|
|
return p;
|
||
|
|
}
|