X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=hacks%2Flmorph.c;fp=hacks%2Flmorph.c;h=11099d26bcb58ced25ff3b344f8f44ba9705ae95;hb=df7adbee81405e2849728a24b498ad2117784b1f;hp=0000000000000000000000000000000000000000;hpb=41fae2ad67bc37e31c4d967bae81e4f3f50fa55a;p=xscreensaver diff --git a/hacks/lmorph.c b/hacks/lmorph.c new file mode 100644 index 00000000..11099d26 --- /dev/null +++ b/hacks/lmorph.c @@ -0,0 +1,513 @@ + +/************************************************************************** + * + * FILE lmorph.c + * MODULE OF xscreensaver + * + * DESCRIPTION Bilinear interpolation for morphing line shapes. + * + * WRITTEN BY Sverre H. Huseby Glenn T. Lines + * Kurvn. 30 Østgaardsgt. 5 + * N-0495 Oslo N-0474 Oslo + * Norway Norway + * + * Phone: +47 901 63 579 Phone: +47 22 04 67 28 + * E-mail: sverrehu@online.no E-mail: gtl@si.sintef.no + * URL: http://home.sol.no/~sverrehu/ + * + * The original idea, and the bilinear interpolation + * mathematics used, emerged in the head of the wise + * Glenn T. Lines. + * + * MODIFICATIONS june 1998 (shh) + * * Minor code cleanup. + * + * march 1997 (shh) + * * Added -mailfile option to allow checking for + * new mail while the screensaver is active. + * + * january 1997 (shh) + * * Some code reformatting. + * * Added possibility to use float arithmetic. + * * Added -figtype option. + * * Made color blue default. + * + * december 1995 (jwz) + * * Function headers converted from ANSI to K&R. + * * Added posibility for random number of steps, and + * made this the default. + * + * march 1995 (shh) + * * Converted from an MS-Windows program to X Window. + * + **************************************************************************/ + +#include +#include +#include +#include +#include "screenhack.h" + +/************************************************************************** + * * + * P R I V A T E D A T A * + * * + **************************************************************************/ + +/* define MARGINS to make some space around the figure. */ +#define MARGINS + +/* define USE_FLOAT to avoid using integer calculations in + createPoints. integer calculation is supposed to be faster, but it + won't work for displays larger than 2048x2048 or so pixels. */ +#undef USE_FLOAT + +#define MAXFIGS 20 +#define TWO_PI (2.0 * M_PI) +#define RND(x) (random() % (x)) + +#define FT_OPEN 1 +#define FT_CLOSED 2 +#define FT_ALL (FT_OPEN | FT_CLOSED) + +static int + numFigs = 0, /* number of figure arrays. */ + numPoints, /* number of points in each array. */ + nWork, /* current work array number. */ + nFrom, /* current from array number. */ + nTo, /* current to array number. */ + figType; +static long delay; /* usecs to wait between updates. */ +static XPoint + *aWork[2], /* working arrays. */ + *a[MAXFIGS], /* the figure arrays. */ + *aTmp, /* used as source when interrupting morph */ + *aPrev, /* previous points displayed. */ + *aCurr, /* the current points displayed. */ + *aFrom, /* figure converting from. */ + *aTo; /* figure converting to. */ +static int scrWidth, scrHeight; +static double currGamma, maxGamma = 1.0, deltaGamma; +static GC gcDraw, gcClear; +static Display *dpy; +static Window window; + + + +/************************************************************************** + * * + * P U B L I C D A T A * + * * + **************************************************************************/ + +char *progclass = "LMorph"; + +char *defaults [] = { + ".background: black", + ".foreground: blue", + "*points: 150", + "*steps: 0", + "*delay: 50000", + "*figtype: all", + 0 +}; + +XrmOptionDescRec options [] = { + { "-points", ".points", XrmoptionSepArg, 0 }, + { "-steps", ".steps", XrmoptionSepArg, 0 }, + { "-delay", ".delay", XrmoptionSepArg, 0 }, + { "-figtype", ".figtype", XrmoptionSepArg, 0 }, + { 0, 0, 0, 0 } +}; +int options_size = (sizeof (options) / sizeof (options[0])); + + + +/************************************************************************** + * * + * P R I V A T E F U N C T I O N S * + * * + **************************************************************************/ + +static void * +xmalloc(size_t size) +{ + void *ret; + + if ((ret = malloc(size)) == NULL) { + fprintf(stderr, "lmorph: out of memory\n"); + exit(1); + } + return ret; +} + +static void +initPointArrays(void) +{ + int q, w, + mx, my, /* max screen coordinates. */ + mp, /* max point number. */ + s, rx, ry, + marginx, marginy; + double scalex, scaley; + + mx = scrWidth - 1; + my = scrHeight - 1; + mp = numPoints - 1; + + aWork[0] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + aWork[1] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + aTmp = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + + if (figType & FT_CLOSED) { + /* rectangle */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + s = numPoints / 4; + for (q = 0; q < s; q++) { + a[numFigs][q].x = ((double) q / s) * mx; + a[numFigs][q].y = 0; + a[numFigs][s + q].x = mx; + a[numFigs][s + q].y = ((double) q / s) * my; + a[numFigs][2 * s + q].x = mx - ((double) q / s) * mx; + a[numFigs][2 * s + q].y = my; + a[numFigs][3 * s + q].x = 0; + a[numFigs][3 * s + q].y = my - ((double) q / s) * my; + } + for (q = 4 * s; q < numPoints; q++) + a[numFigs][q].x = a[numFigs][q].y = 0; + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + rx * sin(1 * TWO_PI * (double) q / mp); + a[numFigs][q].y = my / 2 + ry * cos(3 * TWO_PI * (double) q / mp); + } + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + ry * sin(3 * TWO_PI * (double) q / mp); + a[numFigs][q].y = my / 2 + ry * cos(1 * TWO_PI * (double) q / mp); + } + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + ry + * (0.8 - 0.2 * sin(30 * TWO_PI * q / mp)) + * sin(TWO_PI * (double) q / mp); + a[numFigs][q].y = my / 2 + ry + * (0.8 - 0.2 * sin(30 * TWO_PI * q / mp)) + * cos(TWO_PI * (double) q / mp); + } + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + ry * sin(TWO_PI * (double) q / mp); + a[numFigs][q].y = my / 2 + ry * cos(TWO_PI * (double) q / mp); + } + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + rx * cos(TWO_PI * (double) q / mp); + a[numFigs][q].y = my / 2 + ry * sin(TWO_PI * (double) q / mp); + } + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + rx * sin(2 * TWO_PI * (double) q / mp); + a[numFigs][q].y = my / 2 + ry * cos(3 * TWO_PI * (double) q / mp); + } + a[numFigs][mp].x = a[numFigs][0].x; + a[numFigs][mp].y = a[numFigs][0].y; + ++numFigs; + } + + if (figType & FT_OPEN) { + /* sine wave, one period */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = ((double) q / numPoints) * mx; + a[numFigs][q].y = (1.0 - sin(((double) q / mp) * TWO_PI)) + * my / 2.0; + } + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = ((double) q / mp) * mx; + a[numFigs][q].y = (1.0 - cos(((double) q / mp) * 3 * TWO_PI)) + * my / 2.0; + } + ++numFigs; + + /* spiral, one endpoint at bottom */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + ry * sin(5 * TWO_PI * (double) q / mp) + * ((double) q / mp); + a[numFigs][q].y = my / 2 + ry * cos(5 * TWO_PI * (double) q / mp) + * ((double) q / mp); + } + ++numFigs; + + /* spiral, one endpoint at top */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + rx = mx / 2; + ry = my / 2; + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = mx / 2 + ry * sin(6 * TWO_PI * (double) q / mp) + * ((double) q / mp); + a[numFigs][q].y = my / 2 - ry * cos(6 * TWO_PI * (double) q / mp) + * ((double) q / mp); + } + ++numFigs; + + /* */ + a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint)); + for (q = 0; q < numPoints; q++) { + a[numFigs][q].x = ((double) q / mp) * mx; + a[numFigs][q].y = (1.0 - sin(((double) q / mp) * 5 * TWO_PI)) + * my / 2.0; + } + ++numFigs; + } + +#ifdef MARGINS + /* make some space around the figures. */ + marginx = (mx + 1) / 10; + marginy = (my + 1) / 10; + scalex = (double) ((mx + 1) - 2.0 * marginx) / (mx + 1.0); + scaley = (double) ((my + 1) - 2.0 * marginy) / (my + 1.0); + for (q = 0; q < numFigs; q++) + for (w = 0; w < numPoints; w++) { + a[q][w].x = marginx + a[q][w].x * scalex; + a[q][w].y = marginy + a[q][w].y * scaley; + } +#endif +} + +static void +initLMorph(void) +{ + int steps; + XGCValues gcv; + XWindowAttributes wa; + Colormap cmap; + char *ft; + + numPoints = get_integer_resource("points", "Integer"); + steps = get_integer_resource("steps", "Integer"); + delay = get_integer_resource("delay", "Integer"); + ft = get_string_resource("figtype", "String"); + + if (strcmp(ft, "all") == 0) + figType = FT_ALL; + else if (strcmp(ft, "open") == 0) + figType = FT_OPEN; + else if (strcmp(ft, "closed") == 0) + figType = FT_CLOSED; + else { + fprintf(stderr, "figtype should be `all', `open' or `closed'.\n"); + figType = FT_ALL; + } + + if (steps <= 0) + steps = (random() % 400) + 100; + + deltaGamma = 1.0 / steps; + XGetWindowAttributes(dpy, window, &wa); + scrWidth = wa.width; + scrHeight = wa.height; + cmap = wa.colormap; + gcv.foreground = get_pixel_resource("foreground", "Foreground", dpy, cmap); + gcDraw = XCreateGC(dpy, window, GCForeground, &gcv); + XSetForeground(dpy, gcDraw, gcv.foreground); + gcv.foreground = get_pixel_resource("background", "Background", dpy, cmap); + gcClear = XCreateGC(dpy, window, GCForeground, &gcv); + XClearWindow(dpy, window); + + srandom(time(NULL)); + initPointArrays(); + aCurr = aWork[nWork = 0]; + aPrev = NULL; + currGamma = maxGamma + 1.0; /* force creation of new figure at startup */ + nTo = RND(numFigs); + + { /* jwz for version 2.11 */ + int width = random() % 10; + int style = LineSolid; + int cap = (width > 1 ? CapRound : CapButt); + int join = (width > 1 ? JoinRound : JoinBevel); + if (width == 1) width = 0; + XSetLineAttributes(dpy, gcDraw, width, style, cap, join); + XSetLineAttributes(dpy, gcClear, width, style, cap, join); + } +} + +/* 55% of execution time */ +static void +createPoints(void) +{ + int q; + XPoint *pa = aCurr, *pa1 = aFrom, *pa2 = aTo; +#ifdef USE_FLOAT + float fg, f1g; +#else + long lg, l1g; +#endif + +#ifdef USE_FLOAT + fg = currGamma; + f1g = 1.0 - currGamma; +#else + lg = 8192L * currGamma; + l1g = 8192L * (1.0 - currGamma); +#endif + for (q = numPoints; q; q--) { +#ifdef USE_FLOAT + pa->x = (short) (f1g * pa1->x + fg * pa2->x); + pa->y = (short) (f1g * pa1->y + fg * pa2->y); +#else + pa->x = (short) ((l1g * pa1->x + lg * pa2->x) / 8192L); + pa->y = (short) ((l1g * pa1->y + lg * pa2->y) / 8192L); +#endif + ++pa; + ++pa1; + ++pa2; + } +} + +/* 36% of execution time */ +static void +drawImage(void) +{ + int q; + XPoint *old0, *old1, *new0, *new1; + + /* Problem: update the window without too much flickering. I do + * this by handling each linesegment separately. First remove a + * line, then draw the new line. The problem is that this leaves + * small black pixels on the figure. To fix this, I draw the + * entire figure using XDrawLines() afterwards. */ + if (aPrev) { + old0 = aPrev; + old1 = aPrev + 1; + new0 = aCurr; + new1 = aCurr + 1; + for (q = numPoints - 1; q; q--) { + XDrawLine(dpy, window, gcClear, + old0->x, old0->y, old1->x, old1->y); + XDrawLine(dpy, window, gcDraw, + new0->x, new0->y, new1->x, new1->y); + ++old0; + ++old1; + ++new0; + ++new1; + } + } + XDrawLines(dpy, window, gcDraw, aCurr, numPoints, CoordModeOrigin); + + XFlush(dpy); +} + +/* neglectible % of execution time */ +static void +animateLMorph(void) +{ + if (currGamma > maxGamma) { + currGamma = 0.0; + if (maxGamma == 1.0) { + nFrom = nTo; + aFrom = a[nFrom]; + } else { + memcpy(aTmp, aCurr, numPoints * sizeof(XPoint)); + aFrom = aTmp; + nFrom = -1; + } + do { + nTo = RND(numFigs); + } while (nTo == nFrom); + aTo = a[nTo]; + if (RND(2)) { + /* reverse the array to get more variation. */ + int i1, i2; + XPoint p; + + for (i1 = 0, i2 = numPoints - 1; i1 < numPoints / 2; i1++, i2--) { + p = aTo[i1]; + aTo[i1] = aTo[i2]; + aTo[i2] = p; + } + } + /* occationally interrupt the next run. */ + if (RND(4) == 0) + maxGamma = 0.1 + 0.7 * (RND(1001) / 1000.0); /* partial run */ + else + maxGamma = 1.0; /* full run */ + } + + createPoints(); + drawImage(); + aPrev = aCurr; + aCurr = aWork[nWork ^= 1]; + + currGamma += deltaGamma; +} + + + +/************************************************************************** + * * + * P U B L I C F U N C T I O N S * + * * + **************************************************************************/ + +void +screenhack(Display *disp, Window win) +{ + dpy = disp; + window = win; + initLMorph(); + for (;;) { + animateLMorph(); + screenhack_handle_events (dpy); + usleep(delay); + } +}