Files
Mozilla/mozilla/gfx/src/imgScaler.cpp
pedemont%us.ibm.com ea87ed26c6 Bug 195022 - Workaround fix for scaling images with a 1-bit mask. r=sfraser,sr=tor
git-svn-id: svn://10.0.0.236/trunk@157314 18797224-902f-48f8-a5cc-f745e15eee43
2004-06-02 16:00:29 +00:00

310 lines
8.9 KiB
C++

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* 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 mozilla.org code.
*
* The Initial Developer of the Original Code is
* Tomas Mšller.
* Portions created by the Initial Developer are Copyright (C) 2001
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Tomas Mšller
* Tim Rowley <tor@cs.brown.edu>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <stdlib.h>
#include <stdio.h>
#include "imgScaler.h"
// Scaling code from Graphics Gems book III
// http://www.acm.org/pubs/tog/GraphicsGems/gemsiii/fastBitmap.c
//
// License states - "All code here can be used without restrictions."
// http://www.acm.org/pubs/tog/GraphicsGems/
/*
Fast Bitmap Stretching
Tomas Mšller
*/
static void
Stretch32(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride);
static void
Stretch24(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride);
static void
Stretch8(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride);
static void
Stretch1(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride);
/**********************************************************
RectStretch enlarges or diminishes a source rectangle of a bitmap to
a destination rectangle. The source rectangle is selected by the two
points (xs1,ys1) and (xs2,ys2), and the destination rectangle by
(xd1,yd1) and (xd2,yd2). Since readability of source-code is wanted,
some optimizations have been left out for the reader: It's possible
to read one line at a time, by first stretching in x-direction and
then stretching that bitmap in y-direction.
Entry:
aSrcWidth, aSrcHeight - size of entire original image
aDstWidth, aDstHeight - size of entire scaled image
aStartColumn, aStartRow - upper corner of desired area (inclusive)
aEndColumn, aEndRow - bottom corner of desired area (inclusive)
unsigned char *aSrcImage, aSrcStride - start of original image data
unsigned char *aDstStride, aDstStride - start of desired area image data
unsigned aDepth - bit depth of image (24, 8, or 1)
**********************************************************/
NS_GFX_(void)
RectStretch(unsigned aSrcWidth, unsigned aSrcHeight,
unsigned aDstWidth, unsigned aDstHeight,
unsigned aStartColumn, unsigned aStartRow,
unsigned aEndColumn, unsigned aEndRow,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride,
unsigned aDepth)
{
int e;
unsigned dx, dy;
void (*Stretch)(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn,
unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride);
unsigned xs1, ys1, xs2, ys2, xd1, yd1, xd2, yd2;
xs1 = ys1 = xd1 = yd1 = 0;
xs2 = aSrcWidth - 1;
ys2 = aSrcHeight - 1;
xd2 = aDstWidth - 1;
yd2 = aDstHeight - 1;
// fprintf(stderr, "RS (%d %d)-(%d %d) (%d %d)-(%d %d) %d %d %d\n",
// xs1, ys1, xs2, ys2, xd1, yd1, xd2, yd2,
// aSrcStride, aDstStride, aDepth);
switch (aDepth) {
case 32:
Stretch = Stretch32;
break;
case 24:
Stretch = Stretch24;
break;
case 8:
Stretch = Stretch8;
break;
case 1:
Stretch = Stretch1;
break;
default:
return;
}
dx = yd2 - yd1;
dy = ys2 - ys1;
e = dy - dx;
dy += 1;
if (!dx)
dx = 1;
for (yd1 = 0; yd1 <= aEndRow; yd1++) {
if (yd1 >= aStartRow)
Stretch(xd1, xd2, xs1, xs2, ys1, yd1,
aStartRow, aStartColumn, aEndColumn,
aSrcImage, aSrcStride, aDstImage, aDstStride);
while (e >= 0) {
ys1++;
e -= dx;
}
e += dy;
}
}
/**********************************************************
Stretches a horizontal source line onto a horizontal destination
line. Used by RectStretch.
Entry:
x1,x2 - x-coordinates of the destination line
y1,y2 - x-coordinates of the source line
yr - y-coordinate of source line
yw - y-coordinate of destination line
**********************************************************/
static void
Stretch32(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride)
{
int e;
unsigned dx, dy, d;
unsigned char *src, *dst;
dx = x2 - x1;
dy = y2 - y1;
e = dy - dx;
dy += 1;
src = aSrcImage + yr * aSrcStride + 4 * y1;
dst = aDstImage + (yw - aStartRow) * aDstStride;
if (!dx)
dx = 1;
for (d = 0; d <= aEndColumn; d++) {
if (d >= aStartColumn) {
*dst++ = src[0];
*dst++ = src[1];
*dst++ = src[2];
*dst++ = src[3];
}
while (e >= 0) {
src += 4;
e -= dx;
}
e += dy;
}
}
static void
Stretch24(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride)
{
int e;
unsigned dx, dy, d;
unsigned char *src, *dst;
dx = x2 - x1;
dy = y2 - y1;
e = dy - dx;
dy += 1;
src = aSrcImage + yr * aSrcStride + 3 * y1;
dst = aDstImage + (yw - aStartRow) * aDstStride;
if (!dx)
dx = 1;
for (d = 0; d <= aEndColumn; d++) {
if (d >= aStartColumn) {
*dst++ = src[0];
*dst++ = src[1];
*dst++ = src[2];
}
while (e >= 0) {
src += 3;
e -= dx;
}
e += dy;
}
}
static void
Stretch8(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride)
{
int e;
unsigned dx, dy, d;
unsigned char *src, *dst;
dx = x2 - x1;
dy = y2 - y1;
e = dy - dx;
dy += 1;
src = aSrcImage + yr * aSrcStride + y1;
dst = aDstImage + (yw - aStartRow) * aDstStride;
if (!dx)
dx = 1;
for (d = 0; d <= aEndColumn; d++) {
if (d >= aStartColumn) {
*dst = *src;
dst++;
}
while (e >= 0) {
src++;
e -= dx;
}
e += dy;
}
}
static void
Stretch1(unsigned x1, unsigned x2, unsigned y1, unsigned y2,
unsigned yr, unsigned yw,
unsigned aStartRow, unsigned aStartColumn, unsigned aEndColumn,
unsigned char *aSrcImage, unsigned aSrcStride,
unsigned char *aDstImage, unsigned aDstStride)
{
int e;
unsigned dx, dy, d;
dx = x2 - x1;
dy = y2 - y1;
e = dy - dx;
dy += 1;
if (!dx)
dx = 1;
for (d = 0; d <= aEndColumn; d++) {
if ((d >= aStartColumn) &&
(*(aSrcImage + yr * aSrcStride + (y1 >> 3)) & 1 << (7 - y1 & 0x7)))
*(aDstImage +
(yw - aStartRow) * aDstStride +
((x1 - aStartColumn) >> 3))
|= 1 << (7 - x1 & 0x7);
while (e >= 0) {
y1++;
e -= dx;
}
x1++;
e += dy;
}
}