/*
* Copyright (c) 1996, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
/*
* This file contains macro definitions for the Scaling category of
* the macros used by the generic scaleloop function.
*
* This implementation uses a simple equation which simply chooses
* the closest input pixel to the location which is obtained from
* mapping inversely from the output rectangle to the input rectangle.
* The input pixels will be replicated when scaling larger than the
* original image size since the same input pixel will be chosen for
* more than one output pixel. Conversely, when scaling smaller than
* the original image size, the input pixels will be omitted as needed
* to pare them down to the required number of samples for the output
* image. If there is no scaling occurring in one or both directions
* the macros attempt to short-circuit most of the more complicated
* calculations in an attempt to impose little cost for using this
* implementation in the general case. The calculations also do not
* impose any restrictions on the order of delivery of the pixels.
*
* This file can be used to provide the default implementation of the
* Scaling macros, handling both scaled and unscaled cases and any
* order of pixel delivery.
*/
#define DeclareScaleVars \
int dstX1, dstY1, dstX, dstY, dstX2, dstY2; \
int srcX1, srcXinc, srcXrem, srcXincrem, srcX1increm; \
int srcX, srcY, inputadjust;
#define SRCX srcX
#define SRCY srcY
#define DSTX dstX
#define DSTY dstY
#define DSTX1 dstX1
#define DSTY1 dstY1
#define DSTX2 dstX2
#define DSTY2 dstY2
#define InitScale(pixels, srcOff, srcScan, \
srcOX, srcOY, srcW, srcH, \
srcTW, srcTH, dstTW, dstTH) \
do { \
inputadjust = srcScan; \
if (srcTW == dstTW) { \
inputadjust -= srcW; \
dstX1 = srcOX; \
dstX2 = srcOX + srcW; \
} else { \
dstX1 = DEST_XY_RANGE_START(srcOX, srcTW, dstTW); \
dstX2 = DEST_XY_RANGE_START(srcOX+srcW, srcTW, dstTW); \
if (dstX2 <= dstX1) { \
return SCALENOOP; \
} \
srcX1 = SRC_XY(dstX1, srcTW, dstTW); \
srcXinc = srcTW / dstTW; \
srcXrem = (2 * srcTW) % (2 * dstTW); \
srcX1increm = (((2 * (dstX1) * (srcTW)) + (srcTW)) \
% (2 * (dstTW))); \
} \
if (srcTH == dstTH) { \
dstY1 = srcOY; \
dstY2 = srcOY + srcH; \
SetInputRow(pixels, srcOff, srcScan, srcOY, srcOY); \
} else { \
dstY1 = DEST_XY_RANGE_START(srcOY, srcTH, dstTH); \
dstY2 = DEST_XY_RANGE_START(srcOY+srcH, srcTH, dstTH); \
if (dstY2 <= dstY1) { \
return SCALENOOP; \
} \
} \
} while (0)
#define RowLoop(srcOY) \
for (dstY = dstY1; dstY < dstY2; dstY++)
#define RowSetup(srcTH, dstTH, srcTW, dstTW, \
srcOY, pixels, srcOff, srcScan) \
do { \
if (srcTH == dstTH) { \
srcY = dstY; \
} else { \
srcY = SRC_XY(dstY, srcTH, dstTH); \
SetInputRow(pixels, srcOff, srcScan, srcY, srcOY); \
} \
if (srcTW != dstTW) { \
srcXincrem = srcX1increm; \
srcX = srcX1; \
} \
} while (0)
#define ColLoop(srcOX) \
for (dstX = dstX1; dstX < dstX2; dstX++)
#define ColSetup(srcTW, dstTW, pixel) \
do { \
if (srcTW == dstTW) { \
srcX = dstX; \
pixel = GetPixelInc(); \
} else { \
pixel = GetPixel(srcX); \
srcX += srcXinc; \
srcXincrem += srcXrem; \
if (srcXincrem >= (2 * dstTW)) { \
srcXincrem -= (2 * dstTW); \
srcX++; \
} \
} \
} while (0)
#define RowEnd(srcTH, dstTH, srcW, srcScan) \
do { \
if (srcTH == dstTH) { \
InputPixelInc(inputadjust); \
} \
} while (0)