--- /dev/null
+/* MetaBalls, Copyright (c) 2002-2003 W.P. van Paassen <peter@paassen.tmfweb.nl>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation. No representations are made about the suitability of this
+ * software for any purpose. It is provided "as is" without express or
+ * implied warranty.
+ *
+ * Module - "metaballs.c"
+ *
+ * [01/24/03] - W.P. van Paassen: Additional features
+ * [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
+ * [12/26/02] - W.P. van Paassen: Creation for the Demo Effects Collection (http://demo-effects.sourceforge.net)
+ */
+
+#include <math.h>
+#include "screenhack.h"
+#include <X11/Xutil.h>
+
+/*#define VERBOSE*/
+
+char *progclass = "Metaballs";
+
+char *defaults [] = {
+ ".background: black",
+ ".foreground: white",
+ "*color: random",
+ "*count: 10",
+ "*cycles: 1000",
+ "*ncolors: 256",
+ "*delay: 5000",
+ "*radius: 100",
+ "*delta: 3",
+ 0
+};
+
+XrmOptionDescRec options [] = {
+ { "-color", ".color", XrmoptionSepArg, 0 },
+ { "-ncolors", ".ncolors", XrmoptionSepArg, 0 },
+ { "-count", ".count", XrmoptionSepArg, 0 },
+ { "-delay", ".delay", XrmoptionSepArg, 0 },
+ { "-cycles", ".cycles", XrmoptionSepArg, 0 },
+ { "-radius", ".radius", XrmoptionSepArg, 0 },
+ { "-delta", ".delta", XrmoptionSepArg, 0 },
+ { 0, 0, 0, 0 }
+};
+
+static unsigned short iWinWidth, iWinHeight;
+static char *sColor;
+
+/*blob structure*/
+typedef struct
+{
+ short xpos,ypos;
+} BLOB;
+
+static unsigned char nBlobCount;
+static unsigned char radius;
+static unsigned char delta;
+static unsigned char dradius;
+static unsigned short sradius;
+static unsigned char **blob;
+static BLOB *blobs;
+static unsigned char **blub;
+
+static void init_blob(BLOB *blob)
+{
+ blob->xpos = (iWinWidth>> 1) - radius;
+ blob->ypos = (iWinHeight >> 1) - radius;
+}
+
+static void Execute( Display *pDisplay,
+ Window MainWindow,
+ GC *pGC, XImage *pImage,
+ signed short iColorCount, unsigned long *aiColorVals )
+{
+ unsigned int i, j, k;
+
+ /* clear blub array */
+ for (i = 0; i < iWinHeight; ++i)
+ memset(blub[i], 0, iWinWidth * sizeof(unsigned char));
+
+ /* move blobs */
+ for (i = 0; i < nBlobCount; i++)
+ {
+ blobs[i].xpos += -delta + (int)((delta + .5f) * frand(2.0));
+ blobs[i].ypos += -delta + (int)((delta + .5f) * frand(2.0));
+ }
+
+ /* draw blobs to blub array */
+ for (k = 0; k < nBlobCount; ++k)
+ {
+ if (blobs[k].ypos > -dradius && blobs[k].xpos > -dradius && blobs[k].ypos < iWinHeight && blobs[k].xpos < iWinWidth)
+ {
+ for (i = 0; i < dradius; ++i)
+ {
+ if (blobs[k].ypos + i >= 0 && blobs[k].ypos + i < iWinHeight)
+ {
+ for (j = 0; j < dradius; ++j)
+ {
+ if (blobs[k].xpos + j >= 0 && blobs[k].xpos + j < iWinWidth)
+ {
+ if (blub[blobs[k].ypos + i][blobs[k].xpos + j] < iColorCount)
+ {
+ if (blub[blobs[k].ypos + i][blobs[k].xpos + j] + blob[i][j] > iColorCount)
+ blub[blobs[k].ypos + i][blobs[k].xpos + j] = iColorCount;
+ else
+ blub[blobs[k].ypos + i][blobs[k].xpos + j] += blob[i][j];
+ }
+ }
+ }
+ }
+ }
+ }
+ else
+ init_blob(blobs + k);
+ }
+
+ memset( pImage->data, 0, pImage->bytes_per_line * pImage->height);
+
+ /* draw blub array to screen */
+ for (i = 0; i < iWinHeight; ++i)
+ {
+ for (j = 0; j < iWinWidth; ++j)
+ {
+ if (aiColorVals[blub[i][j]] > 0)
+ XPutPixel( pImage, j, i, aiColorVals[blub[i][j]] );
+ }
+ }
+
+ XPutImage( pDisplay, MainWindow, *pGC, pImage,
+ 0, 0, 0, 0, iWinWidth, iWinHeight );
+ XSync( pDisplay, False );
+}
+
+static unsigned long * SetPalette(Display *pDisplay, Window Win, char *sColor, signed short *piColorCount )
+{
+ XWindowAttributes XWinAttribs;
+ XColor Color, *aColors;
+ unsigned long *aiColorVals;
+ signed short iColor;
+ float nHalfColors;
+
+ XGetWindowAttributes( pDisplay, Win, &XWinAttribs );
+
+ Color.red = random() % 0xFFFF;
+ Color.green = random() % 0xFFFF;
+ Color.blue = random() % 0xFFFF;
+
+ if( strcasecmp( sColor, "random" ) && !XParseColor( pDisplay, XWinAttribs.colormap, sColor, &Color ) )
+ fprintf( stderr, "%s: color %s not found in database. Choosing to random...\n", progname, sColor );
+
+#ifdef VERBOSE
+ printf( "%s: Base color (RGB): <%d, %d, %d>\n", progclass, Color.red, Color.green, Color.blue );
+#endif /* VERBOSE */
+
+ *piColorCount = get_integer_resource( "ncolors", "Integer" );
+ if( *piColorCount < 2 ) *piColorCount = 2;
+ if( *piColorCount > 255 ) *piColorCount = 255;
+
+ aColors = calloc( *piColorCount, sizeof(XColor) );
+ aiColorVals = calloc( *piColorCount, sizeof(unsigned long) );
+
+ for( iColor=0; iColor<*piColorCount; iColor++ )
+ {
+ nHalfColors = *piColorCount / 2.0F;
+ /* Black -> Base Color */
+ if( iColor < (*piColorCount/2) )
+ {
+ aColors[ iColor ].red = ( Color.red / nHalfColors ) * iColor;
+ aColors[ iColor ].green = ( Color.green / nHalfColors ) * iColor;
+ aColors[ iColor ].blue = ( Color.blue / nHalfColors ) * iColor;
+ }
+ /* Base Color -> White */
+ else
+ {
+ aColors[ iColor ].red = ( ( ( 0xFFFF - Color.red ) / nHalfColors ) * ( iColor - nHalfColors ) ) + Color.red;
+ aColors[ iColor ].green = ( ( ( 0xFFFF - Color.green ) / nHalfColors ) * ( iColor - nHalfColors ) ) + Color.green;
+ aColors[ iColor ].blue = ( ( ( 0xFFFF - Color.blue ) / nHalfColors ) * ( iColor - nHalfColors ) ) + Color.blue;
+ }
+
+ if( !XAllocColor( pDisplay, XWinAttribs.colormap, &aColors[ iColor ] ) )
+ {
+ /* start all over with less colors */
+ XFreeColors( pDisplay, XWinAttribs.colormap, aiColorVals, iColor, 0 );
+ free( aColors );
+ free( aiColorVals );
+ (*piColorCount)--;
+
+ if (*piColorCount < 6)
+ {
+ fprintf (stderr, "%s: insufficient colors!\n",
+ progname);
+ exit (1);
+ }
+
+ aColors = calloc( *piColorCount, sizeof(XColor) );
+ aiColorVals = calloc( *piColorCount, sizeof(unsigned long) );
+ iColor = -1;
+ }
+ else
+ aiColorVals[ iColor ] = aColors[ iColor ].pixel;
+ }
+
+ free( aColors );
+
+ XSetWindowBackground( pDisplay, Win, aiColorVals[ 0 ] );
+
+ return aiColorVals;
+}
+
+
+static void Initialize( Display *pDisplay, Window Win, GC *pGC, XImage **ppImage )
+{
+ XGCValues gcValues;
+ XWindowAttributes XWinAttribs;
+ int iBitsPerPixel, i, j;
+ unsigned int distance_squared;
+ float fraction;
+
+ /* Create the Image for drawing */
+ XGetWindowAttributes( pDisplay, Win, &XWinAttribs );
+
+ /* Find the preferred bits-per-pixel. (jwz) */
+ {
+ int i, pfvc = 0;
+ XPixmapFormatValues *pfv = XListPixmapFormats( pDisplay, &pfvc );
+ for( i=0; i<pfvc; i++ )
+ if( pfv[ i ].depth == XWinAttribs.depth )
+ {
+ iBitsPerPixel = pfv[ i ].bits_per_pixel;
+ break;
+ }
+ if( pfv )
+ XFree (pfv);
+ }
+
+ /* Create the GC. */
+ *pGC = XCreateGC( pDisplay, Win, 0, &gcValues );
+
+ *ppImage = XCreateImage( pDisplay, XWinAttribs.visual, XWinAttribs.depth, ZPixmap, 0, NULL,
+ XWinAttribs.width, XWinAttribs.height, BitmapPad( pDisplay ), 0 );
+ (*ppImage)->data = calloc((*ppImage)->bytes_per_line, (*ppImage)->height);
+
+ iWinWidth = XWinAttribs.width;
+ iWinHeight = XWinAttribs.height;
+
+ /* Get the base color. */
+ sColor = get_string_resource( "color", "Color" );
+
+ /* Get the delta. */
+ delta = get_integer_resource( "delta", "Integer" );
+ if (delta < 1)
+ delta = 1;
+ else if (delta > 20)
+ delta = 20;
+
+ /* Get the radius. */
+ radius = get_integer_resource( "radius", "Integer" );
+ if (radius < 2)
+ radius = 2;
+ if (radius > 100)
+ radius = 100;
+
+ radius = (radius / 100.0) * (iWinHeight >> 3);
+
+ dradius = radius * 2;
+ sradius = radius * radius;
+
+ /* create blob */
+ blob = malloc ( dradius * sizeof(unsigned char*));
+ for (i = 0; i < dradius; ++i)
+ blob[i] = malloc( dradius * sizeof(unsigned char));
+
+ /* create blub array */
+ blub = malloc( iWinHeight * sizeof(unsigned char*));
+ for (i = 0; i < iWinHeight; ++i)
+ blub[i] = malloc( iWinWidth * sizeof(unsigned char));
+
+ /* create blob */
+ for (i = -radius; i < radius; ++i)
+ {
+ for (j = -radius; j < radius; ++j)
+ {
+ distance_squared = i * i + j * j;
+ if (distance_squared <= sradius)
+ {
+ /* compute density */
+ fraction = (float)distance_squared / (float)sradius;
+ blob[i + radius][j + radius] = pow((1.0 - (fraction * fraction)),4.0) * 255.0;
+ }
+ else
+ {
+ blob[i + radius][j + radius] = 0;
+ }
+ }
+ }
+
+ for (i = 0; i < nBlobCount; i++)
+ {
+ init_blob(blobs + i);
+ }
+}
+
+void screenhack(Display *pDisplay, Window Win )
+{
+ GC gc;
+ signed short iColorCount = 0;
+ unsigned long *aiColorVals = NULL;
+ XImage *pImage = NULL;
+#ifdef VERBOSE
+ time_t nTime = time( NULL );
+ unsigned short iFrame = 0;
+#endif /* VERBOSE */
+ int delay, cycles, i;
+
+ nBlobCount = get_integer_resource( "count", "Integer" );
+ if( nBlobCount > 255 ) nBlobCount = 255;
+ if( nBlobCount < 2 ) nBlobCount = 2;
+
+ if( ( blobs = calloc( nBlobCount, sizeof(BLOB) ) ) == NULL )
+ {
+ fprintf( stderr, "%s: Could not allocate %d Blobs\n", progclass, nBlobCount );
+ return;
+ }
+#ifdef VERBOSE
+ printf( "%s: Allocated %d Blobs\n", progclass, nBlobCount );
+#endif /* VERBOSE */
+
+ Initialize( pDisplay, Win, &gc, &pImage );
+
+ delay = get_integer_resource( "delay", "Integer" );
+ cycles = get_integer_resource( "cycles", "Integer" );
+ i = cycles;
+
+ while( 1 )
+ {
+ screenhack_handle_events( pDisplay );
+
+ if( i++ >= cycles )
+ {
+ XWindowAttributes XWinAttribs;
+ XGetWindowAttributes( pDisplay, Win, &XWinAttribs );
+
+ memset( pImage->data, 0, pImage->bytes_per_line * pImage->height );
+ XFreeColors( pDisplay, XWinAttribs.colormap, aiColorVals, iColorCount, 0 );
+ free( aiColorVals );
+ aiColorVals = SetPalette( pDisplay, Win, sColor, &iColorCount );
+ XClearWindow( pDisplay, Win );
+ for (i = 0; i < nBlobCount; i++)
+ {
+ init_blob(blobs + i);
+ }
+ i = 0;
+ }
+
+ Execute( pDisplay, Win, &gc, pImage, iColorCount - 1, aiColorVals );
+
+ if( delay && !(i % 4) )
+ usleep(delay);
+
+#ifdef VERBOSE
+ iFrame++;
+ if( nTime - time( NULL ) )
+ {
+ printf( "%s: %d FPS\n", progclass, iFrame );
+ nTime = time( NULL );
+ iFrame = 0;
+ }
+#endif /* VERBOSE */
+ }
+
+ free( pImage->data );
+ XDestroyImage( pImage );
+ free( aiColorVals );
+ free( blobs );
+ for (i = 0; i < iWinHeight; ++i)
+ free( blub[i] );
+ free( blub );
+ for (i = 0; i < dradius; ++i)
+ free( blob[i] );
+ free( blob );
+}
+
+
+/* End of Module - "metaballs.c" */
+
projects / xscreensaver / blobdiff