jedioutcast/utils/roq2/libim/imvfbrotate.c
2013-04-04 13:07:40 -05:00

2070 lines
28 KiB
C

/**
** $Header: /roq/libim/imvfbrotate.c 1 11/02/99 4:38p Zaphod $
** Copyright (c) 1989-1995 San Diego Supercomputer Center (SDSC)
** a division of General Atomics, San Diego, California, USA
**
** Users and possessors of this source code are hereby granted a
** nonexclusive, royalty-free copyright and design patent license to
** use this code in individual software. License is not granted for
** commercial resale, in whole or in part, without prior written
** permission from SDSC. This source is provided "AS IS" without express
** or implied warranty of any kind.
**
** For further information contact:
** E-Mail: info@sds.sdsc.edu
**
** Surface Mail: Information Center
** San Diego Supercomputer Center
** P.O. Box 85608
** San Diego, CA 92186-9784
** (619) 534-5000
**/
#define HEADER " $Header: /roq/libim/imvfbrotate.c 1 11/02/99 4:38p Zaphod $ "
/**
** FILE
** imvfbrotate.c - Rotate a VFB by a certain angle
**
** PROJECT
** libim - SDSC image manipulation library
**
** DESCRIPTION
** imvfbrotate.c contains code to rotate an image.
** It also has the code to shear an image in the x or y direction
**
** PUBLIC CONTENTS
** d =defined constant
** f =function
** m =defined macro
** t =typedef/struct/union
** v =variable
** ? =other
**
** ImVfbRotate f rotate the vfb
** ImVfbXShear f shear the vfb in the x direction
** ImVfbYShear f shear the vfb in the y direction
**
** PRIVATE CONTENTS
** none
**
** HISTORY
** $Log: /roq/libim/imvfbrotate.c $
*
* 1 11/02/99 4:38p Zaphod
** Revision 1.10 1995/06/30 22:12:11 bduggan
** added some casts
**
** Revision 1.9 1995/06/29 00:28:04 bduggan
** updated copyright year
**
** Revision 1.8 1995/06/16 09:01:05 bduggan
** added some casts
**
** Revision 1.7 94/10/03 11:29:57 nadeau
** Updated to ANSI C and C++ compatibility.
** Removed all use of register keyword.
** Minimized use of custom SDSC types (e.g., uchar vs. unsigned char)
** Changed all float arguments to double.
** Added forward declarations.
** Added misc. casts to passify SGI and DEC compilers.
** Changed all macros and defined constants to have names
** starting with IM.
** Updated comments.
** Updated indenting on some code.
** Updated copyright message.
**
** Revision 1.6 92/12/03 01:56:03 nadeau
** Total rewrite.
**
** Revision 1.5 92/10/19 14:07:23 groening
** *** empty log message ***
**
** Revision 1.4 92/09/17 14:50:14 vle
** Added optional include for M_PI declaration to make some
** compilers happy.
**
** Revision 1.3 92/09/03 16:41:14 groening
** Added more error checks.
**
** Revision 1.2 92/09/02 11:17:02 vle
** Updated copyright notice.
**
** Revision 1.1 92/09/02 11:13:57 groening
** Initial revision
**
**/
/**
** CODE CREDITS
** Custom development, Dave Nadeau, San Diego Supercomputer Center, 1992.
**/
#include <math.h>
#ifndef M_PI
//#include <values.h>
#define M_PI 3.1415926
#endif
#include "iminternal.h"
/*
* FUNCTION
* ImVfbXShear - shear a vfb in the X-direction
*
* DESCRIPTION
* implements this formula x1 = x - tan(degree/2)*y
*
*/
ImVfb * /* Returns resized VFB */
#ifdef __STDC__
ImVfbXShear( ImVfb *srcVfb, double degree, ImVfb *dstVfb)
#else
ImVfbXShear( srcVfb, degree, dstVfb)
ImVfb *srcVfb; /* VFB to resize */
double degree; /* Amount to rotate */
ImVfb *dstVfb; /* Result VFB */
#endif
{
ImVfbPtr pdst; /* Destination VFB pointer */
ImVfbPtr psrc; /* Destination VFB pointer */
int i,j; /* generic integer value */
int fields; /* vfb field description */
int dw, dh; /* width an height */
int newX; /* new x position */
int xDif; /* how much wider new vfb is */
double tandegree; /* tangent of degree/2 */
/*
* make sure there is a source vfb then make sure dst vfb
* has the same fields as the source.
*/
if ( srcVfb == IMVFBNULL )
{
ImErrNo = IMENOVFB ;
return (IMVFBNULL);
}
/*
* Floating point modulo 'degree' by 360.0.
*/
degree *= 2.0;
degree -= ((int)(degree / 360.0)) * 360.0;
/*
* Make sure that a valid shear degree was requested.
*/
if ( (degree <= -180.0) || (degree >= 180.0) )
{
ImErrNo = IMEIMPSHEAR;
return (IMVFBNULL);
}
if ( degree < 0.0 )
degree += 360.0;
degree *= -(M_PI/180);
/*
* figure out the necessary size for the resulting vfb
*/
if ( degree > -M_PI )
{
dw = (int)( 0.5 + ImVfbQWidth(srcVfb) -
tan(degree/2)*ImVfbQHeight( srcVfb ));
xDif = 0;
dh = ImVfbQHeight( srcVfb );
}
else
{
dw = (int)( 0.5 + ImVfbQWidth(srcVfb) +
tan(degree/2)*ImVfbQHeight( srcVfb ));
xDif = dw-ImVfbQWidth(srcVfb);
dh = ImVfbQHeight( srcVfb );
}
/*
* If the user hasn't given us a destination VFB, make one.
* If they have given us a destination VFB, make sure it is usable.
*/
fields = ImVfbQFields( srcVfb );
if ( dstVfb == IMVFBNEW )
{
dstVfb = ImVfbAlloc( dw, dh, fields );
if( dstVfb == IMVFBNULL )
{
ImErrNo = IMEMALLOC;
return( IMVFBNULL );
}
ImVfbClear( fields, 0, dstVfb );
}
else
{
/* make sure that the passed vfb is the correct size */
if ( ImVfbQWidth( dstVfb ) < dw )
{
ImErrNo = IMEWIDTH;
return ( IMVFBNULL );
}
if ( ImVfbQHeight( dstVfb ) < dh )
{
ImErrNo = IMEHEIGHT;
return ( IMVFBNULL );
}
if (( ImVfbQFields(srcVfb) & ImVfbQFields(dstVfb)) !=
ImVfbQFields(srcVfb))
{
ImErrNo = IMEFIELD;
return (IMVFBNULL);
}
}
/*
* Now shear the vfb
*/
tandegree = tan( degree / 2 );
psrc = ImVfbQFirst(srcVfb);
for (i=0; i<ImVfbQHeight(srcVfb); i++)
{
for (j=0; j<ImVfbQWidth(srcVfb); j++)
{
newX = (int)(j - tandegree*i + xDif + 0.5);
pdst = ImVfbQPtr (dstVfb,newX,i);
if (fields & IMVFBRGB)
{
ImVfbSRed (dstVfb, pdst, ImVfbQRed (srcVfb, psrc) );
ImVfbSGreen (dstVfb, pdst,ImVfbQGreen(srcVfb, psrc));
ImVfbSBlue (dstVfb, pdst, ImVfbQBlue(srcVfb, psrc) );
}
if (fields & IMVFBFDATA)
{
ImVfbSFData (dstVfb, pdst, ImVfbQFData (srcVfb, psrc) );
}
if (fields & IMVFBIDATA)
{
ImVfbSIData (dstVfb, pdst, ImVfbQIData (srcVfb, psrc) );
}
if (fields & IMVFBWPROT)
{
ImVfbSWProt (dstVfb, pdst, ImVfbQWProt (srcVfb, psrc) );
}
if (fields & IMVFBZ)
{
ImVfbSZ (dstVfb, pdst, ImVfbQZ (srcVfb, psrc) );
}
if (fields & IMVFBMONO)
{
ImVfbSMono (dstVfb, pdst, ImVfbQMono (srcVfb, psrc) );
}
if (fields & IMVFBINDEX8)
{
ImVfbSIndex8 (dstVfb, pdst, ImVfbQIndex8 (srcVfb, psrc) );
}
if (fields & IMVFBINDEX16)
{
ImVfbSIndex16 (dstVfb,pdst, ImVfbQIndex16 (srcVfb, psrc) );
}
if (fields & IMVFBALPHA)
{
ImVfbSAlpha (dstVfb, pdst, ImVfbQAlpha (srcVfb, psrc) );
}
ImVfbSInc(srcVfb,psrc);
}
}
return( dstVfb );
}
/*
* FUNCTION
* ImVfbYShear - shear a vfb in the x-direction
*
* DESCRIPTION
* implements this formula x1 = x - tan(degree/2)*y
*
*/
ImVfb * /* Returns resized VFB */
#ifdef __STDC__
ImVfbYShear( ImVfb *srcVfb, double degree, ImVfb *dstVfb)
#else
ImVfbYShear( srcVfb, degree, dstVfb)
ImVfb *srcVfb; /* VFB to resize */
double degree; /* Amount to rotate */
ImVfb *dstVfb; /* Result VFB */
#endif
{
ImVfbPtr pdst; /* Destination VFB pointer */
ImVfbPtr psrc; /* Destination VFB pointer */
int i,j; /* generic integer value */
int fields; /* vfb field description */
int dw, dh; /* width an height */
int newY; /* new x position */
int yDif; /* amount to adjust shear by to get pos. value*/
double sindegree; /* Sine of angle */
/*
* make sure there is a source vfb then make sure dst vfb
* has the same fields as the source.
*/
if ( srcVfb == IMVFBNULL )
{
ImErrNo = IMENOVFB ;
return (IMVFBNULL);
}
/*
* Floating point modulo 'degree' by 360.0.
*/
degree *= 2.0;
degree -= ((int)(degree / 360.0)) * 360.0;
/*
* Make sure that a valid shear degree was requested.
*/
if ( (degree <= -180.0) || (degree >= 180.0) )
{
ImErrNo = IMEIMPSHEAR;
return (IMVFBNULL);
}
if ( degree < 0.0 )
degree += 360.0;
degree *= -(M_PI/180);
/*
* figure out the necessary size for the resulting vfb
*/
if ( degree>-M_PI )
{
dh = (int)(( 0.5 + ImVfbQHeight(srcVfb) -
sin(degree)*ImVfbQWidth( srcVfb )));
dw = ImVfbQWidth( srcVfb );
yDif = dh-ImVfbQHeight(srcVfb);
}
else
{
dh = (int)(( 0.5 + ImVfbQHeight(srcVfb) +
sin(degree)*ImVfbQWidth( srcVfb )));
dw = ImVfbQWidth( srcVfb );
yDif = 0;
}
/*
* If the user hasn't given us a destination VFB, make one.
* If they have given us a destination VFB, make sure it is usable.
*/
fields = ImVfbQFields( srcVfb );
if ( dstVfb == IMVFBNEW )
{
dstVfb = ImVfbAlloc( dw, dh, fields );
if( dstVfb == IMVFBNULL )
{
ImErrNo = IMEMALLOC;
return( IMVFBNULL );
}
ImVfbClear( fields, 0, dstVfb );
}
else
{
/* make sure that passed vfb is the correct size */
if ( ImVfbQWidth( dstVfb ) < dw )
{
ImErrNo = IMEWIDTH;
return ( IMVFBNULL );
}
if ( ImVfbQHeight( dstVfb ) < dh )
{
ImErrNo = IMEHEIGHT;
return ( IMVFBNULL );
}
if (( ImVfbQFields(srcVfb) & ImVfbQFields(dstVfb)) !=
ImVfbQFields(srcVfb))
{
ImErrNo = IMEFIELD;
return (IMVFBNULL);
}
}
/*
* Now shear the vfb
*/
psrc = ImVfbQFirst(srcVfb);
sindegree = sin( degree );
for (i=0; i<ImVfbQHeight(srcVfb); i++)
{
for (j=0; j<ImVfbQWidth(srcVfb); j++)
{
newY = (int)(i + sindegree * j + yDif + 0.5);
pdst = ImVfbQPtr (dstVfb,j,newY);
if (fields & IMVFBRGB)
{
ImVfbSRed (dstVfb, pdst, ImVfbQRed (srcVfb, psrc) );
ImVfbSGreen (dstVfb, pdst,ImVfbQGreen(srcVfb, psrc));
ImVfbSBlue (dstVfb, pdst, ImVfbQBlue(srcVfb, psrc) );
}
if (fields & IMVFBFDATA)
{
ImVfbSFData (dstVfb, pdst, ImVfbQFData (srcVfb, psrc) );
}
if (fields & IMVFBIDATA)
{
ImVfbSIData (dstVfb, pdst, ImVfbQIData (srcVfb, psrc) );
}
if (fields & IMVFBZ)
{
ImVfbSZ (dstVfb, pdst, ImVfbQZ (srcVfb, psrc) );
}
if (fields & IMVFBALPHA)
{
ImVfbSAlpha (dstVfb, pdst, ImVfbQAlpha (srcVfb, psrc) );
}
if (fields & IMVFBWPROT)
{
ImVfbSWProt (dstVfb, pdst, ImVfbQWProt (srcVfb, psrc) );
}
if (fields & IMVFBMONO)
{
ImVfbSMono (dstVfb, pdst, ImVfbQMono (srcVfb, psrc) );
}
if (fields & IMVFBINDEX8)
{
ImVfbSIndex8 (dstVfb, pdst, ImVfbQIndex8 (srcVfb, psrc) );
}
if (fields & IMVFBINDEX16)
{
ImVfbSIndex16 (dstVfb,pdst, ImVfbQIndex16 (srcVfb, psrc) );
}
ImVfbSInc(srcVfb,psrc);
}
}
return( dstVfb );
}
/*
* FUNCTION
* ImVfbRotate - rotate an image
*
* DESCRIPTION
* Rotation consists of three shears in X, Y then X again. We
* accomplish this using the ImVfbXShear and ImVfbYShear routines.
*
* The job is complicated by a need to be able to put the rotated
* result back into an already existing destination VFB. That VFB
* may already have image data in it:
*
* Source VFB +
* +---+ / S \
* |SSS| rotated by 45 degrees = + SSS +
* +---+ \ S /
* +
*
* Desination VFB
* +-------+ +---+---+
* |DDDDDDD| |D/ S \D|
* |DDDDDDD| with the rotated source pasted in = |+ SSS +|
* |DDDDDDD| |D\ S /D|
* +-------+ +---+---+
*
* Note that the corners of the final image still have the original
* destination image's contents. Only the central portion has been
* overwritten by the rotated source.
*
* In order to paste the rotated source onto the destination, we must
* know what pixels of the rotated source came from the original source,
* and what pixels are "empty" background pixels.
*
* We could compute these edges and do a simple bresenham line walk to
* "fill" a polygon in the destination from the rotated source.
* Unfortunately, when we tried that, the bresenham walk computed a
* slightly different edge than actually occured from the chain of
* shears. This was not acceptable.
*
* Instead, we now create a dummy monochrome VFB that we initially fill
* with 1's. Then, each time we shear the source image, we also shear
* the dummy VFB. On each shear, the dummy's corners are filled in
* with 0's by the shear algorithm. When we're done we have a rotated
* dummy image with a rotated rectangle of 1's amidst a field of 0's.
*
* Finally, this dummy VFB is used as a key to tell us which pixels in
* the true rotated source are from the original image. Those pixels
* are copied into the destination and we throw out the dummy.
*
* Rotation by successive shearing works as follows:
*
* 1. Shear in X.
* 2. Shear in Y
* 3. Trim excess from VFB to minimize VFB size.
* 4. Shear in X again.
* 5. Trim excess from VFB to minimize VFB size.
* 6. Copy across into destination.
*/
ImVfb * /* Returns rotated VFB */
#ifdef __STDC__
ImVfbRotate( ImVfb* sorceVfb, double rotation, ImVfb* dstVfb)
#else
ImVfbRotate( sorceVfb, rotation, dstVfb)
ImVfb *sorceVfb; /* VFB to resize */
double rotation; /* Amount to rotate in degrees NOT radians */
ImVfb *dstVfb; /* VFB to resize */
#endif
{
ImVfb *tmpVfb; /* Temporary VFB holder */
ImVfb *srcVfb; /* Temporary VFB copy */
ImVfb *dummyVfb; /* Bogus VFB */
ImVfbPtr pSrc, pDst, pDummy; /* VFB pixel pointers */
int H,W,Wone,Wtwo,Hone; /* Heights and widths of vfb's */
int srcXLeft, srcYTop,srcDX, srcDY;
int fieldMask; /* Field mask of incomin vfb */
float rad; /* Radian equivalent of rotation */
int i,j; /* counters */
/*
* Make sure we have a source image.
*/
if ( sorceVfb == IMVFBNULL )
{
ImErrNo = IMENOVFB ;
return (IMVFBNULL);
}
fieldMask = ImVfbQFields( sorceVfb );
W = ImVfbQWidth(sorceVfb);
H = ImVfbQHeight(sorceVfb);
/*
* Modulo the rotation angle by 360.0, make it positive,
* and convert to radians.
*/
rotation -= ((int)(rotation / 360.0)) * 360.0;
if ( rotation < 0 )
rotation += 360.0;
rad = rotation*(M_PI/180);
/*
* Make a destination VFB if one was not given. Otherwise make
* sure the one given is big enough.
*/
srcDX = (int) (0.5 + fabs( sin( rad )*H ) + fabs(cos( rad )*W ));
srcDY = (int) (0.5 + fabs( sin( rad )*W ) + fabs(cos( rad )*H ));
if ( dstVfb == IMVFBNEW )
{
/*
* Make dstVfb.
*/
if ( (dstVfb = ImVfbAlloc( srcDX, srcDY, fieldMask))==IMVFBNULL)
{
ImErrNo = IMEMALLOC;
return (IMVFBNULL);
}
ImVfbClear( fieldMask, 0, dstVfb );
}
else
{
if ( ImVfbQWidth( dstVfb ) != srcDX )
{
ImErrNo = IMEWIDTH;
return (IMVFBNULL);
}
if ( ImVfbQHeight( dstVfb ) != srcDY )
{
ImErrNo = IMEHEIGHT;
return (IMVFBNULL);
}
if ( (fieldMask & ImVfbQFields(dstVfb)) != fieldMask )
{
ImErrNo = IMEFIELD;
return (IMVFBNULL);
}
}
/*
* Rotations greater than 90 degrees introduce severe aliasing
* effects. Do 90 degree rotates until the rotation angle is
* less than 90. Then we'll do the fancy <90 method to do the rest.
*/
srcVfb = sorceVfb;
while ( rotation >= 90.0 )
{
if ( (tmpVfb = ImVfb90Rotate( srcVfb, IMVFBNEW )) == IMVFBNULL )
{
ImErrNo = IMEMALLOC;
return (IMVFBNULL);
}
rad -= (M_PI/2.0);
rotation -= 90.0;
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
srcVfb = tmpVfb;
}
W = ImVfbQWidth( srcVfb );
H = ImVfbQHeight( srcVfb );
if ( rotation == 0.0 )
{
/*
* Nothing more to do. Easy! Copy the rotated image into
* the destination VFB and return.
*/
if ( ImVfbCopy( srcVfb , 0, 0, W, H, fieldMask,
dstVfb, 0, 0 ) == IMVFBNULL)
{
/* ImErrNo already set. */
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
return ( IMVFBNULL );
}
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
return ( dstVfb );
}
/*
* Compute ultimate image size.
*/
Wone = (int) (W + 0.5 + H * fabs(tan(rad/2)));
Hone = (int) (H + 0.5 + fabs(sin(rad)) * Wone);
Wtwo = (int) (0.5 + Wone + Hone*fabs(tan(rad/2)));
srcYTop = (int)(0.5 + fabs(tan(rad/2))*(fabs(sin(rad))*H));
srcXLeft = (int) (0.5 + fabs(sin(rad)) * ( (W)*fabs(tan(rad/2))));
srcDX = (int) (0.5 + fabs(sin(rad))*H + fabs (cos(rad)*W));
srcDY = (int) (0.5 + fabs(sin(rad))*W + fabs (cos(rad)*H));
srcDY +=2;
if (srcDY>Hone)
srcDY=Hone;
if (srcYTop>1.0)
srcYTop--;
rotation /= 2.0;
/*
* Create a dummy monochrome VFB filled with 1's.
*/
if ( (dummyVfb = ImVfbAlloc( W, H, IMVFBMONO )) == IMVFBNULL)
{
/* ImErrNo already set. */
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
return (IMVFBNULL);
}
if ( ImVfbFill( dummyVfb, 0, 0, W, H, IMMONO, 1.0, 1.0,
IMVFBINSIDE, IMGRADNONE, dummyVfb ) == IMVFBNULL )
{
/* ImErrNo already set. */
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
/*
* Shear in X.
*/
if ( (tmpVfb = ImVfbXShear( srcVfb, rotation, IMVFBNEW ) ) == IMVFBNULL)
{
/* ImErrNo already set. */
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
if ( srcVfb != sorceVfb )
ImVfbFree( srcVfb );
srcVfb = tmpVfb;
if ( (tmpVfb = ImVfbXShear( dummyVfb, rotation, IMVFBNEW)) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( dummyVfb );
dummyVfb = tmpVfb;
/*
* Shear in Y.
*/
if ( (tmpVfb = ImVfbYShear( srcVfb, rotation, IMVFBNEW ) ) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( srcVfb );
srcVfb = tmpVfb;
if ( (tmpVfb = ImVfbYShear( dummyVfb, rotation, IMVFBNEW)) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( dummyVfb );
dummyVfb = tmpVfb;
/*
* Trim off the excess that comes about by increasing the size to
* shear in X, then increasing the size to shear in Y. We end up
* with a lot of extra "empty" space around the image. By trimming
* it off here, we save time later by having fewer pixels to move
* about.
*/
if ( (tmpVfb = ImVfbCopy( srcVfb, 0, srcYTop, Wone, srcDY,
fieldMask, IMVFBNEW, 0, 0)) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( srcVfb );
srcVfb = tmpVfb;
if ( (tmpVfb = ImVfbCopy( dummyVfb, 0, srcYTop, Wone, srcDY,
IMVFBMONO, IMVFBNEW, 0, 0)) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( dummyVfb );
dummyVfb = tmpVfb;
/*
* Shear in X again.
*/
if ( (tmpVfb = ImVfbXShear( srcVfb, rotation, IMVFBNEW ) ) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( srcVfb );
srcVfb = tmpVfb;
if ( (tmpVfb = ImVfbXShear( dummyVfb, rotation, IMVFBNEW)) == IMVFBNULL)
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( dummyVfb );
dummyVfb = tmpVfb;
/*
* Trim off the excess again.
*/
if ( (tmpVfb = ImVfbCopy( srcVfb, srcXLeft, 0, srcDX,
srcDY, fieldMask, IMVFBNEW, 0, 0 )) == IMVFBNULL )
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( srcVfb );
srcVfb = tmpVfb;
if ( (tmpVfb = ImVfbCopy( dummyVfb, srcXLeft, 0, srcDX,
srcDY, IMVFBMONO, IMVFBNEW, 0, 0 )) == IMVFBNULL )
{
/* ImErrNo already set. */
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return (IMVFBNULL);
}
ImVfbFree( dummyVfb );
dummyVfb = tmpVfb;
/*
* Use the dummyVfb has a mask for the rotated srcVfb to determine
* which pixels of the srcVfb to copy to the dstVfb. 1's in the
* dummyVfb mean copy. 0's mean don't.
*/
pSrc = ImVfbQFirst( srcVfb );
pDummy = ImVfbQFirst( dummyVfb );
pDst = ImVfbQFirst( dstVfb );
for ( i = 0; i < ImVfbQHeight( dummyVfb ); i++ )
{
for ( j = 0; j < ImVfbQWidth( dummyVfb) ; j++ )
{
if ( !ImVfbQMono( dummyVfb, pDummy ) )
{
/* Don't copy. */
ImVfbSInc( dummyVfb, pDummy );
ImVfbSInc( srcVfb, pSrc );
ImVfbSInc( dstVfb, pDst );
continue;
}
/* Do copy. */
if (fieldMask&IMVFBRGB)
{
ImVfbSRed( dstVfb, pDst,
ImVfbQRed( srcVfb, pSrc));
ImVfbSGreen( dstVfb, pDst,
ImVfbQGreen( srcVfb, pSrc));
ImVfbSBlue( dstVfb, pDst,
ImVfbQBlue( srcVfb, pSrc));
}
if (fieldMask&IMVFBZ)
ImVfbSZ( dstVfb, pDst,
ImVfbQZ( srcVfb, pSrc ) );
if (fieldMask&IMVFBWPROT)
ImVfbSWProt( dstVfb, pDst,
ImVfbQWProt( srcVfb, pSrc ) );
if (fieldMask&IMVFBIDATA)
ImVfbSIData( dstVfb, pDst,
ImVfbQIData( srcVfb, pSrc ) );
if (fieldMask&IMVFBFDATA)
ImVfbSFData( dstVfb, pDst,
ImVfbQFData( srcVfb, pSrc ) );
if (fieldMask&IMVFBMONO)
ImVfbSMono( dstVfb, pDst,
ImVfbQMono( srcVfb, pSrc ) );
if (fieldMask&IMVFBALPHA)
ImVfbSAlpha( dstVfb, pDst,
ImVfbQAlpha( srcVfb, pSrc ) );
if (fieldMask&IMVFBINDEX8)
ImVfbSIndex8( dstVfb, pDst,
ImVfbQIndex8( srcVfb, pSrc ) );
if (fieldMask&IMVFBINDEX16)
ImVfbSIndex16( dstVfb, pDst,
ImVfbQIndex16( srcVfb, pSrc ) );
ImVfbSInc( dummyVfb, pDummy );
ImVfbSInc( srcVfb, pSrc );
ImVfbSInc( dstVfb, pDst );
}
}
ImVfbFree( srcVfb );
ImVfbFree( dummyVfb );
return( dstVfb );
}
/*
* FUNCTION
* ImVfb90Rotate - rotate by 90 degrees
*
* DESCRIPTION
* When rotating by exactly 90 degrees counter-clockwise (right-hand
* rule), we can do the rotation quicker than by using 3 shears.
*/
ImVfb * /* Returns rotated VFB */
#ifdef __STDC__
ImVfb90Rotate( ImVfb* sourceVfb, ImVfb* dstVfb )
#else
ImVfb90Rotate( sourceVfb, dstVfb )
ImVfb *sourceVfb; /* VFB to rotated */
ImVfb *dstVfb; /* VFB to return rotated */
#endif
{
ImVfbPtr psrc; /* pointer into source vfb */
ImVfbPtr pdst; /* pointer into destination vfb */
int i,j; /* Counters */
int wDst, hDst; /* Destination width and height */
int fieldMask; /* Fields to deal with */
/*
* Get destination width and height... reversed from source's
* `cause we're rotating by 90.0.
*/
hDst = ImVfbQWidth( sourceVfb );
wDst = ImVfbQHeight( sourceVfb );
fieldMask = ImVfbQFields( sourceVfb );
/*
* If a destination VFB wasn't given, allocate one at the same
* size and depth as the source. Otherwise make sure the desination
* is the same size as the source and has at least the same fields
* as the source.
*/
if (dstVfb == IMVFBNEW)
{
if ( (dstVfb = ImVfbAlloc( wDst, hDst, fieldMask )) ==IMVFBNULL)
{
ImErrNo = IMEMALLOC;
return (IMVFBNULL);
}
}
else
{
if ( ImVfbQWidth( dstVfb ) != wDst )
{
ImErrNo = IMEWIDTH;
return (IMVFBNULL);
}
if ( ImVfbQHeight( dstVfb ) != hDst )
{
ImErrNo = IMEHEIGHT;
return (IMVFBNULL);
}
if ( (fieldMask & ImVfbQFields(dstVfb)) != fieldMask )
{
ImErrNo = IMEFIELD;
return (IMVFBNULL);
}
}
/*
* Walk the image and rotate it by 90 into the destination VFB.
*/
psrc = ImVfbQFirst( sourceVfb );
for ( i = 0; i < wDst; i++ )
{
for ( j = hDst-1; j >= 0; j-- )
{
pdst = ImVfbQPtr( dstVfb, i, j );
if (fieldMask&IMVFBRGB)
{
ImVfbSRed (dstVfb, pdst, ImVfbQRed(sourceVfb, psrc));
ImVfbSGreen (dstVfb, pdst, ImVfbQGreen(sourceVfb, psrc));
ImVfbSBlue (dstVfb, pdst, ImVfbQBlue(sourceVfb, psrc));
}
if (fieldMask&IMVFBZ)
{
ImVfbSZ (dstVfb, pdst, ImVfbQZ(sourceVfb, psrc));
}
if (fieldMask&IMVFBWPROT)
{
ImVfbSWProt (dstVfb, pdst, ImVfbQWProt(sourceVfb, psrc));
}
if (fieldMask&IMVFBIDATA)
{
ImVfbSIData (dstVfb, pdst, ImVfbQIData(sourceVfb, psrc));
}
if (fieldMask&IMVFBFDATA)
{
ImVfbSFData (dstVfb, pdst, ImVfbQFData(sourceVfb, psrc));
}
if (fieldMask&IMVFBMONO)
{
ImVfbSMono (dstVfb, pdst, ImVfbQMono(sourceVfb, psrc));
}
if (fieldMask&IMVFBALPHA)
{
ImVfbSAlpha (dstVfb, pdst, ImVfbQAlpha(sourceVfb, psrc));
}
if (fieldMask&IMVFBINDEX8)
{
ImVfbSIndex8 (dstVfb, pdst, ImVfbQIndex8(sourceVfb, psrc));
}
if (fieldMask&IMVFBINDEX16)
{
ImVfbSIndex16 (dstVfb, pdst, ImVfbQIndex16(sourceVfb, psrc));
}
ImVfbSInc( sourceVfb, psrc );
}
}
return (dstVfb);
}