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/*************************************************************************
** Bitmap.cpp **
** **
** This file is part of dvisvgm -- the DVI to SVG converter **
** Copyright (C) 2005-2014 Martin Gieseking <martin.gieseking@uos.de> **
** **
** 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; either version 3 of **
** the License, or (at your option) any later version. **
** **
** 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, see <http://www.gnu.org/licenses/>. **
*************************************************************************/
#include <config.h>
#include <algorithm>
#include <cstdlib>
#include <iostream>
#include "Bitmap.h"
#include "macros.h"
using namespace std;
Bitmap::Bitmap () : _rows(0), _cols(0), _xshift(0), _yshift(0), _bpr(0), _bytes(0)
{
}
/** Constructs a Bitmap */
Bitmap::Bitmap (int minx, int maxx, int miny , int maxy) {
resize(minx, maxx, miny, maxy);
}
/** Resizes the bitmap and clears all pixels.
* @param[in] minx index of leftmost pixel column
* @param[in] maxx index of rightmost pixel column
* @param[in] miny index of bottom row
* @param[in] maxy index of top row */
void Bitmap::resize (int minx, int maxx, int miny , int maxy) {
_rows = abs(maxy-miny)+1;
_cols = abs(maxx-minx)+1;
_xshift = minx;
_yshift = miny;
_bpr = _cols/8 + (_cols % 8 ? 1 : 0); // bytes per row
_bytes.resize(_rows*_bpr);
FORALL(_bytes, vector<UInt8>::iterator, it)
*it = 0;
}
/** Sets n pixels of row r to 1 starting at pixel c.
* @param[in] r number of row
* @param[in] c number of column (pixel)
* @param[in] n number of bits to be set */
void Bitmap::setBits (int r, int c, int n) {
r -= _yshift;
c -= _xshift;
UInt8 *byte = &_bytes[r*_bpr + c/8];// + (c%8 ? 1 : 0);
while (n > 0) {
int b = 7 - c%8; // number of leftmost bit in current byte to be set
int m = min(n, b+1); // number of bits to be set in current byte
int bitseq = (1 << m)-1; // sequence of n set bits (bits 0..n-1 are set)
bitseq <<= b-m+1; // move bit sequence so that bit b is the leftmost set bit
*byte |= UInt8(bitseq); // apply bit sequence to current byte
byte++;
n -= m;
c += m;
}
}
void Bitmap::forAllPixels (ForAllData &data) const {
for (int y=_rows-1; y >= 0 ; y--) {
for (int c=0; c < _bpr; c++) {
UInt8 byte = _bytes[y*_bpr+c];
int x;
for (int b=7; (b >= 0) && ((x = 8*c+(7-b)) < _cols); b--) {
data.pixel(x, y, byte & (1 << b), *this);
}
}
}
}
struct BBoxData : public Bitmap::ForAllData
{
BBoxData () : maxx(0), maxy(0) {}
void pixel (int x, int y, bool set, const Bitmap &bm) {
if (set) {
maxx = max(maxx, x);
maxy = max(maxy, y);
}
}
int maxx, maxy;
};
void Bitmap::bbox (int &w, int &h) const {
BBoxData data;
forAllPixels(data);
w = data.maxx+1;
h = data.maxy+1;
}
ostream& Bitmap::write (ostream &os) const {
#if 0
for (int r=_rows-1; r >= 0 ; r--) {
for (int c=0; c < _bpr; c++) {
UInt8 byte = _bytes[r*_bpr+c];
for (int b=128; b; b>>=1)
os << (byte & b ? '*' : '-');
os << ' ';
}
os << endl;
}
#endif
return os;
}
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