+++ /dev/null
-
-/**************************************************************************
- *
- * FILE lmorph.c
- * MODULE OF xscreensaver
- *
- * DESCRIPTION Bilinear interpolation for morphing line shapes.
- *
- * WRITTEN BY Sverre H. Huseby Glenn T. Lines
- * Maridalsvn. 122, leil 101 Frysjavn. 3, 5. etg.
- * N-0461 Oslo N-0883 Oslo
- * Norway Norway
- *
- * Phone: +47 22 71 99 08 Phone: +47 22 23 71 99
- * E-mail: sverrehu@ifi.uio.no E-mail: gtl@si.sintef.no
- *
- * The original idea, and the bilinear interpolation
- * mathematics used, emerged in the head of the wise
- * Glenn Terje Lines.
- *
- * MODIFICATIONS march 1995
- * * Converted from an MS-Windows program to X Window.
- *
- **************************************************************************/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#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 MAXFIGS 20
-#define TWO_PI (2.0 * M_PI)
-#define RND(x) (random() % (x))
-static int
- cFig = 0, /* Number of figure arrays. */
- cPoint, /* Number of points in each array. */
- nWork, /* Current work array number. */
- nFrom, /* Current from array number. */
- nTo; /* Current to array number. */
-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 double
- gam,
- maxGamma = 1.0,
- delta_gam;
-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 [] = {
- "LMorph.background: black",
- "LMorph.foreground: green",
- "*points: 150",
- "*steps: 0",
- "*delay: 50000",
- 0
-};
-
-XrmOptionDescRec options [] = {
- { "-points", ".points", XrmoptionSepArg, 0 },
- { "-steps", ".steps", XrmoptionSepArg, 0 },
- { "-delay", ".delay", XrmoptionSepArg, 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)
- size_t size;
-{
- void *ret;
-
- if ((ret = malloc(size)) == NULL) {
- fprintf(stderr, "lmorph: out of memory\n");
- exit(1);
- }
- return ret;
-}
-
-
-
-static double frnd()
-{
- /*
- * Hm. for some reason the second line (using RAND_MAX) didn't
- * work on some machines, so I always use the first.
- */
-#undef RAND_MAX
-#ifndef RAND_MAX
- return (double) (random() & 0x7FFF) / 0x7FFF;
-#else
- return ((double) random()) / RAND_MAX;
-#endif
-}
-
-
-
-static void initPointArrays()
-{
- XWindowAttributes wa;
- int q, w,
- mx, my, /* Max screen coordinates. */
- mp, /* Max point number. */
- s, rx, ry,
- marginx, marginy;
- double scalex, scaley;
-
- XGetWindowAttributes(dpy, window, &wa);
- mx = wa.width - 1;
- my = wa.height - 1;
- mp = cPoint - 1;
-
- aWork[0] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- aWork[1] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- aTmp = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
-
-
- /*
- * Figure 0
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- s = cPoint / 4;
- for (q = 0; q < s; q++) {
- a[cFig][q].x = ((double) q / s) * mx;
- a[cFig][q].y = 0;
- a[cFig][s + q].x = mx;
- a[cFig][s + q].y = ((double) q / s) * my;
- a[cFig][2 * s + q].x = mx - ((double) q / s) * mx;
- a[cFig][2 * s + q].y = my;
- a[cFig][3 * s + q].x = 0;
- a[cFig][3 * s + q].y = my - ((double) q / s) * my;
- }
- for (q = 4 * s; q < cPoint; q++)
- a[cFig][q].x = a[cFig][q].y = 0;
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 1
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = ((double) q / cPoint) * mx;
- a[cFig][q].y = (1.0 - sin(((double) q / mp) * TWO_PI)) * my / 2.0;
- }
- ++cFig;
-
- /*
- * Figure 2
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + rx * sin(1 * TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * cos(3 * TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 3
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + ry * sin(3 * TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * cos(1 * TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 4
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + ry * (1 - 0.1 * frnd())
- * sin(TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * (1 - 0.1 * frnd())
- * cos(TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 5
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + ry * (0.8 - 0.2 * sin(30 * TWO_PI * q / mp))
- * sin(TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * (0.8 - 0.2 * sin(30 * TWO_PI * q / mp))
- * cos(TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 6
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + ry * sin(TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * cos(TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 7
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + rx * cos(TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * sin(TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 8
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = ((double) q / mp) * mx;
- a[cFig][q].y = (1.0 - cos(((double) q / mp) * 3 * TWO_PI)) * my / 2.0;
- }
- ++cFig;
-
- /*
- * Figure 9
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + rx * sin(2 * TWO_PI * (double) q / mp);
- a[cFig][q].y = my / 2 + ry * cos(3 * TWO_PI * (double) q / mp);
- }
- a[cFig][mp].x = a[cFig][0].x;
- a[cFig][mp].y = a[cFig][0].y;
- ++cFig;
-
- /*
- * Figure 10
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + ry * sin(5 * TWO_PI * (double) q / mp)
- * ((double) q / mp);
- a[cFig][q].y = my / 2 + ry * cos(5 * TWO_PI * (double) q / mp)
- * ((double) q / mp);
- }
- ++cFig;
-
- /*
- * Figure 11
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- rx = mx / 2;
- ry = my / 2;
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = mx / 2 + ry * sin(6 * TWO_PI * (double) q / mp)
- * ((double) q / mp);
- a[cFig][q].y = my / 2 - ry * cos(6 * TWO_PI * (double) q / mp)
- * ((double) q / mp);
- }
- ++cFig;
-
- /*
- * Figure 12
- */
- a[cFig] = (XPoint *) xmalloc(cPoint * sizeof(XPoint));
- for (q = 0; q < cPoint; q++) {
- a[cFig][q].x = ((double) q / mp) * mx;
- a[cFig][q].y = (1.0 - sin(((double) q / mp) * 5 * TWO_PI)) * my / 2.0;
- }
- ++cFig;
-
-#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 < cFig; q++)
- for (w = 0; w < cPoint; w++) {
- a[q][w].x = marginx + a[q][w].x * scalex;
- a[q][w].y = marginy + a[q][w].y * scaley;
- }
-#endif
-}
-
-
-
-static void createPoints()
-{
- int q;
- XPoint *pa = aCurr, *pa1 = aFrom, *pa2 = aTo;
- long lg, l1g;
-
-
- lg = 8192L * gam, l1g = 8192L * (1.0 - gam);
- for (q = 0; q < cPoint; q++) {
- pa->x = (short) ((l1g * pa1->x + lg * pa2->x) / 8192L);
- pa->y = (short) ((l1g * pa1->y + lg * pa2->y) / 8192L);
- ++pa;
- ++pa1;
- ++pa2;
- }
-}
-
-
-static void drawImage()
-{
- register 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 = cPoint - 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, cPoint, CoordModeOrigin);
- XFlush(dpy);
-}
-
-static void initLMorph()
-{
- int steps;
- XGCValues gcv;
- XWindowAttributes wa;
- Colormap cmap;
-
- cPoint = get_integer_resource("points", "Integer");
- steps = get_integer_resource("steps", "Integer");
- delay = get_integer_resource("delay", "Integer");
-
- if (steps <= 0)
- steps = (random() % 400) + 100;
-
- delta_gam = 1.0 / steps;
- XGetWindowAttributes(dpy, window, &wa);
- 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;
- gam = 2.0;
- nTo = RND(cFig);
-}
-
-static void animateLMorph()
-{
- if (gam > maxGamma) {
- gam = 0.0;
- if (maxGamma == 1.0) {
- nFrom = nTo;
- aFrom = a[nFrom];
- } else {
- memcpy(aTmp, aCurr, cPoint * sizeof(XPoint));
- aFrom = aTmp;
- nFrom = -1;
- }
- do {
- nTo = RND(cFig);
- } 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 = cPoint - 1; i1 < cPoint / 2; i1++, i2--) {
- p = aTo[i1];
- aTo[i1] = aTo[i2];
- aTo[i2] = p;
- }
- }
- /*
- * It may be nice to interrupt the next run.
- */
- if (RND(3) > 0)
- maxGamma = 0.1 + 0.7 * (RND(1001) / 1000.0);
- else
- maxGamma = 1.0;
- }
-
- createPoints();
- drawImage();
- aPrev = aCurr;
- aCurr = aWork[nWork ^= 1];
-
- gam += delta_gam;
-}
-
-
-
-/**************************************************************************
- * *
- * P U B L I C F U N C T I O N S *
- * *
- **************************************************************************/
-
-void screenhack(disp, win)
- Display *disp;
- Window win;
-{
- dpy = disp;
- window = win;
- initLMorph();
- for (;;) {
- animateLMorph();
- screenhack_usleep(delay);
- }
-}
projects / xscreensaver / blobdiff