/*!
\file Draw_FillEllipse.c
\author Mario Palomo <mpalomo@ihman.com>
\author Jose M. de la Huerga Fernández
\author Pepe González Mora
\date 05-2002
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Foundation,
Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#if SDL_DRAW_BPP == 1
#define SDL_DRAW_PUTPIXEL \
memset(((Uint8*)super->pixels+ (y0+y)*super->pitch+ (x0-x)), \
color, 2*x+1); \
memset(((Uint8*)super->pixels+ (y0-y)*super->pitch+ (x0-x)), \
color, 2*x+1);
#elif SDL_DRAW_BPP == 2
#define SDL_DRAW_PUTPIXEL \
{ \
p0 = ((Uint8*)super->pixels+ (y0+y)*super->pitch+ (x0-x)*2); \
p1 = ((Uint8*)super->pixels+ (y0-y)*super->pitch+ (x0-x)*2); \
i = 2*x+1; \
switch( i % 4 ) { \
do{ \
case 0: *(Uint16*)p0 = color; *(Uint16*)p1 = color; \
p0+=2; p1+=2; \
case 3: *(Uint16*)p0 = color; *(Uint16*)p1 = color; \
p0+=2; p1+=2; \
case 2: *(Uint16*)p0 = color; *(Uint16*)p1 = color; \
p0+=2; p1+=2; \
case 1: *(Uint16*)p0 = color; *(Uint16*)p1 = color; \
p0+=2; p1+=2; \
}while( (i-=4) > 0 ); \
} \
}
#elif SDL_DRAW_BPP == 3
#define SDL_DRAW_PUTPIXEL_BPP_3_AUX \
if (SDL_BYTEORDER == SDL_BIG_ENDIAN) { \
p0[0] = colorbyte2; \
p0[1] = colorbyte1; \
p0[2] = colorbyte0; \
p1[0] = colorbyte2; \
p1[1] = colorbyte1; \
p1[2] = colorbyte0; \
} else { \
p0[0] = colorbyte0; \
p0[1] = colorbyte1; \
p0[2] = colorbyte2; \
p1[0] = colorbyte0; \
p1[1] = colorbyte1; \
p1[2] = colorbyte2; \
}
#define SDL_DRAW_PUTPIXEL \
{ \
p0 = ((Uint8*)super->pixels+ (y0+y)*super->pitch+ (x0-x)*3); \
p1 = ((Uint8*)super->pixels+ (y0-y)*super->pitch+ (x0-x)*3); \
i = 2*x+1; \
switch( i % 4 ) { \
do{ \
case 0: SDL_DRAW_PUTPIXEL_BPP_3_AUX \
p0+=3; p1+=3; \
case 3: SDL_DRAW_PUTPIXEL_BPP_3_AUX \
p0+=3; p1+=3; \
case 2: SDL_DRAW_PUTPIXEL_BPP_3_AUX \
p0+=3; p1+=3; \
case 1: SDL_DRAW_PUTPIXEL_BPP_3_AUX \
p0+=3; p1+=3; \
}while( (i-=4) > 0 ); \
} \
}
#elif SDL_DRAW_BPP == 4
#ifdef __linux__
#define SDL_DRAW_WMEMSET_START \
if (sizeof(wchar_t) == sizeof(Uint32)) { \
wmemset( (wchar_t*)((Uint8*)super->pixels+ (y0+y)*super->pitch+ (x0-x)*4), \
color, 2*x+1); \
wmemset( (wchar_t*)((Uint8*)super->pixels+ (y0-y)*super->pitch+ (x0-x)*4), \
color, 2*x+1); \
} else {
#define SDL_DRAW_WMEMSET_END }
#else
#define SDL_DRAW_WMEMSET_START
#define SDL_DRAW_WMEMSET_END
#endif
#define SDL_DRAW_PUTPIXEL \
SDL_DRAW_WMEMSET_START \
p0 = ((Uint8*)super->pixels+ (y0+y)*super->pitch+ (x0-x)*4); \
p1 = ((Uint8*)super->pixels+ (y0-y)*super->pitch+ (x0-x)*4); \
i = 2*x+1; \
switch( i % 4 ) { \
do{ \
case 0: *(Uint32*)p0 = color; *(Uint32*)p1 = color; \
p0+=4; p1+=4; \
case 3: *(Uint32*)p0 = color; *(Uint32*)p1 = color; \
p0+=4; p1+=4; \
case 2: *(Uint32*)p0 = color; *(Uint32*)p1 = color; \
p0+=4; p1+=4; \
case 1: *(Uint32*)p0 = color; *(Uint32*)p1 = color; \
p0+=4; p1+=4; \
}while( (i-=4) > 0 ); \
} \
SDL_DRAW_WMEMSET_END
#endif /*SDL_DRAW_BPP*/
void SDL_DRAWFUNCTION(SDL_Surface *super,
Sint16 x0, Sint16 y0,
Uint16 Xradius, Uint16 Yradius,
Uint32 color)
{
#if SDL_DRAW_BPP == 3
Uint8 colorbyte0 = (Uint8) (color & 0xff);
Uint8 colorbyte1 = (Uint8) ((color >> 8) & 0xff);
Uint8 colorbyte2 = (Uint8) ((color >> 16) & 0xff);
#endif
#if SDL_DRAW_BPP != 1
register Uint8 *p0;
register Uint8 *p1;
register Sint16 i;
#endif
Sint32 x, y;
Sint32 Xchange, Ychange;
Sint32 EllipseError;
Sint32 TwoASquare, TwoBSquare;
Sint32 StoppingX, StoppingY;
TwoASquare = 2*Xradius*Xradius;
TwoBSquare = 2*Yradius*Yradius;
/*1st set of points*/
x = Xradius-1; /*radius zero == draw nothing*/
y = 0;
Xchange = Yradius*Yradius*(1-2*Xradius);
Ychange = Xradius*Xradius;
EllipseError = 0;
StoppingX = TwoBSquare*Xradius;
StoppingY = 0;
/*Plot 2 ellipse scan lines for iteration*/
while (StoppingX > StoppingY) {
SDL_DRAW_PUTPIXEL
++y;
StoppingY += TwoASquare;
EllipseError += Ychange;
Ychange += TwoASquare;
if (( 2*EllipseError + Xchange) > 0) {
--x;
StoppingX -= TwoBSquare;
EllipseError += Xchange;
Xchange += TwoBSquare;
}
}/*while*/
/*2nd set of points*/
x = 0;
y = Yradius-1; /*radius zero == draw nothing*/
Xchange = Yradius*Yradius;
Ychange = Xradius*Xradius*(1-2*Yradius);
EllipseError = 0;
StoppingX = 0;
StoppingY = TwoASquare*Yradius;
/*Plot 2 ellipse scan lines for iteration*/
while (StoppingX < StoppingY) {
SDL_DRAW_PUTPIXEL
++x;
StoppingX += TwoBSquare;
EllipseError += Xchange;
Xchange += TwoBSquare;
if ((2*EllipseError + Ychange) > 0) {
--y;
StoppingY -= TwoASquare;
EllipseError += Ychange;
Ychange += TwoASquare;
}
}
}/*Draw_FillEllipse*/
#undef SDL_DRAW_PUTPIXEL
#undef SDL_DRAW_PUTPIXEL_BPP_3_AUX
#undef SDL_DRAW_WMEMSET_START
#undef SDL_DRAW_WMEMSET_END