1 /* MetaBalls, Copyright (c) 2002-2003 W.P. van Paassen <peter@paassen.tmfweb.nl>
3 * Permission to use, copy, modify, distribute, and sell this software and its
4 * documentation for any purpose is hereby granted without fee, provided that
5 * the above copyright notice appear in all copies and that both that
6 * copyright notice and this permission notice appear in supporting
7 * documentation. No representations are made about the suitability of this
8 * software for any purpose. It is provided "as is" without express or
11 * Module - "metaballs.c"
13 * [01/24/03] - W.P. van Paassen: Additional features
14 * [12/29/02] - W.P. van Paassen: Port to X for use with XScreenSaver, the shadebob hack by Shane Smit was used as a template
15 * [12/26/02] - W.P. van Paassen: Creation for the Demo Effects Collection (http://demo-effects.sourceforge.net)
19 #include "screenhack.h"
20 #include <X11/Xutil.h>
24 char *progclass = "Metaballs";
39 XrmOptionDescRec options [] = {
40 { "-color", ".color", XrmoptionSepArg, 0 },
41 { "-ncolors", ".ncolors", XrmoptionSepArg, 0 },
42 { "-count", ".count", XrmoptionSepArg, 0 },
43 { "-delay", ".delay", XrmoptionSepArg, 0 },
44 { "-cycles", ".cycles", XrmoptionSepArg, 0 },
45 { "-radius", ".radius", XrmoptionSepArg, 0 },
46 { "-delta", ".delta", XrmoptionSepArg, 0 },
50 static unsigned short iWinWidth, iWinHeight;
59 static unsigned int nBlobCount;
60 static unsigned char radius;
61 static unsigned char delta;
62 static unsigned char dradius;
63 static unsigned short sradius;
64 static unsigned char **blob;
66 static unsigned char **blub;
69 #define BELLRAND(n) ((frand((n)) + frand((n)) + frand((n))) / 3)
71 static void init_blob(BLOB *blob)
73 blob->xpos = iWinWidth/4 + BELLRAND(iWinWidth/2) - radius;
74 blob->ypos = iWinHeight/4 + BELLRAND(iWinHeight/2) - radius;
77 static void Execute( Display *pDisplay,
79 GC *pGC, XImage *pImage,
80 signed short iColorCount, unsigned long *aiColorVals )
84 /* clear blub array */
85 for (i = 0; i < iWinHeight; ++i)
86 memset(blub[i], 0, iWinWidth * sizeof(unsigned char));
89 for (i = 0; i < nBlobCount; i++)
91 blobs[i].xpos += -delta + (int)((delta + .5f) * frand(2.0));
92 blobs[i].ypos += -delta + (int)((delta + .5f) * frand(2.0));
95 /* draw blobs to blub array */
96 for (k = 0; k < nBlobCount; ++k)
98 if (blobs[k].ypos > -dradius && blobs[k].xpos > -dradius && blobs[k].ypos < iWinHeight && blobs[k].xpos < iWinWidth)
100 for (i = 0; i < dradius; ++i)
102 if (blobs[k].ypos + i >= 0 && blobs[k].ypos + i < iWinHeight)
104 for (j = 0; j < dradius; ++j)
106 if (blobs[k].xpos + j >= 0 && blobs[k].xpos + j < iWinWidth)
108 if (blub[blobs[k].ypos + i][blobs[k].xpos + j] < iColorCount)
110 if (blub[blobs[k].ypos + i][blobs[k].xpos + j] + blob[i][j] > iColorCount)
111 blub[blobs[k].ypos + i][blobs[k].xpos + j] = iColorCount;
113 blub[blobs[k].ypos + i][blobs[k].xpos + j] += blob[i][j];
121 init_blob(blobs + k);
124 memset( pImage->data, 0, pImage->bytes_per_line * pImage->height);
126 /* draw blub array to screen */
127 for (i = 0; i < iWinHeight; ++i)
129 for (j = 0; j < iWinWidth; ++j)
131 if (aiColorVals[blub[i][j]] > 0)
132 XPutPixel( pImage, j, i, aiColorVals[blub[i][j]] );
136 XPutImage( pDisplay, MainWindow, *pGC, pImage,
137 0, 0, 0, 0, iWinWidth, iWinHeight );
138 XSync( pDisplay, False );
141 static unsigned long * SetPalette(Display *pDisplay, Window Win, char *sColor, signed short *piColorCount )
143 XWindowAttributes XWinAttribs;
144 XColor Color, *aColors;
145 unsigned long *aiColorVals;
149 XGetWindowAttributes( pDisplay, Win, &XWinAttribs );
151 Color.red = random() % 0xFFFF;
152 Color.green = random() % 0xFFFF;
153 Color.blue = random() % 0xFFFF;
155 if( strcasecmp( sColor, "random" ) && !XParseColor( pDisplay, XWinAttribs.colormap, sColor, &Color ) )
156 fprintf( stderr, "%s: color %s not found in database. Choosing to random...\n", progname, sColor );
159 printf( "%s: Base color (RGB): <%d, %d, %d>\n", progclass, Color.red, Color.green, Color.blue );
162 *piColorCount = get_integer_resource( "ncolors", "Integer" );
163 if( *piColorCount < 2 ) *piColorCount = 2;
164 if( *piColorCount > 255 ) *piColorCount = 255;
166 aColors = calloc( *piColorCount, sizeof(XColor) );
167 aiColorVals = calloc( *piColorCount, sizeof(unsigned long) );
169 for( iColor=0; iColor<*piColorCount; iColor++ )
171 nHalfColors = *piColorCount / 2.0F;
172 /* Black -> Base Color */
173 if( iColor < (*piColorCount/2) )
175 aColors[ iColor ].red = ( Color.red / nHalfColors ) * iColor;
176 aColors[ iColor ].green = ( Color.green / nHalfColors ) * iColor;
177 aColors[ iColor ].blue = ( Color.blue / nHalfColors ) * iColor;
179 /* Base Color -> White */
182 aColors[ iColor ].red = ( ( ( 0xFFFF - Color.red ) / nHalfColors ) * ( iColor - nHalfColors ) ) + Color.red;
183 aColors[ iColor ].green = ( ( ( 0xFFFF - Color.green ) / nHalfColors ) * ( iColor - nHalfColors ) ) + Color.green;
184 aColors[ iColor ].blue = ( ( ( 0xFFFF - Color.blue ) / nHalfColors ) * ( iColor - nHalfColors ) ) + Color.blue;
187 if( !XAllocColor( pDisplay, XWinAttribs.colormap, &aColors[ iColor ] ) )
189 /* start all over with less colors */
190 XFreeColors( pDisplay, XWinAttribs.colormap, aiColorVals, iColor, 0 );
195 if (*piColorCount < 6)
197 fprintf (stderr, "%s: insufficient colors!\n",
202 aColors = calloc( *piColorCount, sizeof(XColor) );
203 aiColorVals = calloc( *piColorCount, sizeof(unsigned long) );
207 aiColorVals[ iColor ] = aColors[ iColor ].pixel;
212 XSetWindowBackground( pDisplay, Win, aiColorVals[ 0 ] );
218 static void Initialize( Display *pDisplay, Window Win, GC *pGC, XImage **ppImage )
221 XWindowAttributes XWinAttribs;
222 int iBitsPerPixel, i, j;
223 unsigned int distance_squared;
226 /* Create the Image for drawing */
227 XGetWindowAttributes( pDisplay, Win, &XWinAttribs );
229 /* Find the preferred bits-per-pixel. (jwz) */
232 XPixmapFormatValues *pfv = XListPixmapFormats( pDisplay, &pfvc );
233 for( i=0; i<pfvc; i++ )
234 if( pfv[ i ].depth == XWinAttribs.depth )
236 iBitsPerPixel = pfv[ i ].bits_per_pixel;
244 *pGC = XCreateGC( pDisplay, Win, 0, &gcValues );
246 *ppImage = XCreateImage( pDisplay, XWinAttribs.visual, XWinAttribs.depth, ZPixmap, 0, NULL,
247 XWinAttribs.width, XWinAttribs.height, BitmapPad( pDisplay ), 0 );
248 (*ppImage)->data = calloc((*ppImage)->bytes_per_line, (*ppImage)->height);
250 iWinWidth = XWinAttribs.width;
251 iWinHeight = XWinAttribs.height;
253 /* Get the base color. */
254 sColor = get_string_resource( "color", "Color" );
257 delta = get_integer_resource( "delta", "Integer" );
263 /* Get the radius. */
264 radius = get_integer_resource( "radius", "Integer" );
270 radius = (radius / 100.0) * (iWinHeight >> 3);
271 if (radius >= 128) /* should use UCHAR_MAX? */
272 radius = 127; /* dradius should fit in u_char */
274 dradius = radius * 2;
275 sradius = radius * radius;
278 blob = malloc ( dradius * sizeof(unsigned char*));
279 for (i = 0; i < dradius; ++i)
280 blob[i] = malloc( dradius * sizeof(unsigned char));
282 /* create blub array */
283 blub = malloc( iWinHeight * sizeof(unsigned char*));
284 for (i = 0; i < iWinHeight; ++i)
285 blub[i] = malloc( iWinWidth * sizeof(unsigned char));
288 for (i = -radius; i < radius; ++i)
290 for (j = -radius; j < radius; ++j)
292 distance_squared = i * i + j * j;
293 if (distance_squared <= sradius)
295 /* compute density */
296 fraction = (float)distance_squared / (float)sradius;
297 blob[i + radius][j + radius] = pow((1.0 - (fraction * fraction)),4.0) * 255.0;
301 blob[i + radius][j + radius] = 0;
306 for (i = 0; i < nBlobCount; i++)
308 init_blob(blobs + i);
312 void screenhack(Display *pDisplay, Window Win )
315 signed short iColorCount = 0;
316 unsigned long *aiColorVals = NULL;
317 XImage *pImage = NULL;
319 time_t nTime = time( NULL );
320 unsigned short iFrame = 0;
322 int delay, cycles, i;
324 nBlobCount = get_integer_resource( "count", "Integer" );
325 if( nBlobCount > 255 ) nBlobCount = 255;
326 if( nBlobCount < 2 ) nBlobCount = 2;
328 if( ( blobs = calloc( nBlobCount, sizeof(BLOB) ) ) == NULL )
330 fprintf( stderr, "%s: Could not allocate %d Blobs\n", progclass, nBlobCount );
334 printf( "%s: Allocated %d Blobs\n", progclass, nBlobCount );
337 Initialize( pDisplay, Win, &gc, &pImage );
339 delay = get_integer_resource( "delay", "Integer" );
340 cycles = get_integer_resource( "cycles", "Integer" );
345 screenhack_handle_events( pDisplay );
349 XWindowAttributes XWinAttribs;
350 XGetWindowAttributes( pDisplay, Win, &XWinAttribs );
352 memset( pImage->data, 0, pImage->bytes_per_line * pImage->height );
353 XFreeColors( pDisplay, XWinAttribs.colormap, aiColorVals, iColorCount, 0 );
355 aiColorVals = SetPalette( pDisplay, Win, sColor, &iColorCount );
356 XClearWindow( pDisplay, Win );
357 for (i = 0; i < nBlobCount; i++)
359 init_blob(blobs + i);
364 Execute( pDisplay, Win, &gc, pImage, iColorCount - 1, aiColorVals );
366 if( delay && !(i % 4) )
371 if( nTime - time( NULL ) )
373 printf( "%s: %d FPS\n", progclass, iFrame );
374 nTime = time( NULL );
380 free( pImage->data );
381 XDestroyImage( pImage );
384 for (i = 0; i < iWinHeight; ++i)
387 for (i = 0; i < dradius; ++i)
393 /* End of Module - "metaballs.c" */