-
-/**************************************************************************
- *
- * 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.
+/* lmorph, Copyright (c) 1993-1999 Sverre H. Huseby and Glenn T. Lines
*
- * 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.
- *
- **************************************************************************/
+ * 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.
+ */
+
+/*------------------------------------------------------------------------
+ |
+ | FILE lmorph.c
+ | MODULE OF xscreensaver
+ |
+ | DESCRIPTION Smooth and non-linear morphing between 1D curves.
+ |
+ | 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: glennli@ifi.uio.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 october 1999 (shh)
+ | * Removed option to use integer arithmetic.
+ | * Increased default number of points, and brightened
+ | the foreground color a little bit.
+ | * Minor code cleanup (very minor, that is).
+ | * Default number of steps is no longer random.
+ | * Added -linewidth option (and resource).
+ |
+ | october 1999 (gtl)
+ | * Added cubic interpolation between shapes
+ | * Added non-linear transformation speed
+ |
+ | june 1998 (shh)
+ | * Minor code cleanup.
+ |
+ | 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.
+ |
+ | november 1993 (gtl, shh, lots of beer)
+ | * Original Windows version (we didn't know better).
+ +----------------------------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "screenhack.h"
-/**************************************************************************
- * *
- * P R I V A T E D A T A *
- * *
- **************************************************************************/
+/*-----------------------------------------------------------------------+
+| PRIVATE DATA |
++-----------------------------------------------------------------------*/
/* 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))
nWork, /* current work array number. */
nFrom, /* current from array number. */
nTo, /* current to array number. */
+ nNext, /* current next array number (after to).*/
+ shift, /* shifts the starting point of a figure */
figType;
static long delay; /* usecs to wait between updates. */
static XPoint
*aPrev, /* previous points displayed. */
*aCurr, /* the current points displayed. */
*aFrom, /* figure converting from. */
- *aTo; /* figure converting to. */
+ *aTo, /* figure converting to. */
+ *aNext, /* figure converting to next time. */
+ *aSlopeFrom, /* slope at start of morph */
+ *aSlopeTo; /* slope at end of morph */
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 *
- * *
- **************************************************************************/
+/*-----------------------------------------------------------------------+
+| PUBLIC DATA |
++-----------------------------------------------------------------------*/
char *progclass = "LMorph";
char *defaults [] = {
".background: black",
- ".foreground: blue",
- "*points: 150",
- "*steps: 0",
- "*delay: 50000",
+ ".foreground: #4444FF",
+ "*points: 200",
+ "*steps: 150",
+ "*delay: 70000",
"*figtype: all",
+ "*linewidth: 5",
0
};
XrmOptionDescRec options [] = {
- { "-points", ".points", XrmoptionSepArg, 0 },
- { "-steps", ".steps", XrmoptionSepArg, 0 },
- { "-delay", ".delay", XrmoptionSepArg, 0 },
- { "-figtype", ".figtype", XrmoptionSepArg, 0 },
- { 0, 0, 0, 0 }
+ { "-points", ".points", XrmoptionSepArg, 0 },
+ { "-steps", ".steps", XrmoptionSepArg, 0 },
+ { "-delay", ".delay", XrmoptionSepArg, 0 },
+ { "-figtype", ".figtype", XrmoptionSepArg, 0 },
+ { "-linewidth", ".linewidth", 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 *
- * *
- **************************************************************************/
+/*-----------------------------------------------------------------------+
+| PRIVATE FUNCTIONS |
++-----------------------------------------------------------------------*/
static void *
xmalloc(size_t size)
static void
initPointArrays(void)
{
- int q, w,
- mx, my, /* max screen coordinates. */
- mp, /* max point number. */
- s, rx, ry,
- marginx, marginy;
+ int q, w;
+ int mx, my; /* max screen coordinates. */
+ int mp; /* max point number. */
+ int s, rx, ry;
+ int marginx, marginy;
double scalex, scaley;
mx = scrWidth - 1;
a[numFigs][mp].y = a[numFigs][0].y;
++numFigs;
- /* */
+
+ /* */
a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint));
rx = mx / 2;
ry = my / 2;
a[numFigs][mp].y = a[numFigs][0].y;
++numFigs;
+
/* */
a[numFigs] = (XPoint *) xmalloc(numPoints * sizeof(XPoint));
rx = mx / 2;
XWindowAttributes wa;
Colormap cmap;
char *ft;
-
+ int i;
+
numPoints = get_integer_resource("points", "Integer");
steps = get_integer_resource("steps", "Integer");
delay = get_integer_resource("delay", "Integer");
aPrev = NULL;
currGamma = maxGamma + 1.0; /* force creation of new figure at startup */
nTo = RND(numFigs);
+ do {
+ nNext = RND(numFigs);
+ } while (nNext == nTo);
+
+ aSlopeTo = (XPoint *) xmalloc(numPoints * sizeof(XPoint));
+ aSlopeFrom = (XPoint *) xmalloc(numPoints * sizeof(XPoint));
+ aNext = (XPoint *) xmalloc(numPoints * sizeof(XPoint));
+
+ for (i = 0; i < numPoints ; i++) {
+ aSlopeTo[i].x = 0.0;
+ aSlopeTo[i].y = 0.0;
+ }
- { /* 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);
+ { /* jwz for version 2.11 */
+ /* int width = random() % 10;*/
+ int width = get_integer_resource("linewidth", "Integer");
+ 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);
}
}
static void
createPoints(void)
{
- int q;
+ int q;
XPoint *pa = aCurr, *pa1 = aFrom, *pa2 = aTo;
-#ifdef USE_FLOAT
- float fg, f1g;
-#else
- long lg, l1g;
-#endif
+ XPoint *qa1 = aSlopeFrom, *qa2 = aSlopeTo;
+ float fg, f1g;
+ float speed;
-#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
+ speed = 0.45 * sin(TWO_PI * (double) (q + shift) / (numPoints - 1));
+ fg = currGamma + 1.67 * speed
+ * exp(-200.0 * (currGamma - 0.5 + 0.7 * speed)
+ * (currGamma - 0.5 + 0.7 * speed));
+
+ f1g = 1.0 - fg;
+ pa->x = (short) (f1g * f1g * f1g * pa1->x + f1g * f1g * fg
+ * (3 * pa1->x + qa1->x) + f1g * fg * fg
+ * (3 * pa2->x - qa2->x) + fg * fg * fg * pa2->x);
+ pa->y = (short) (f1g * f1g * f1g * pa1->y + f1g * f1g * fg
+ * (3 * pa1->y + qa1->y) + f1g * fg * fg
+ * (3 * pa2->y - qa2->y) + fg * fg * fg * pa2->y);
+
++pa;
++pa1;
++pa2;
+ ++qa1;
+ ++qa2;
}
}
static void
drawImage(void)
{
- int q;
+ 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
+ * small black pixels on the figure. To fix this, we draw the
* entire figure using XDrawLines() afterwards. */
if (aPrev) {
old0 = aPrev;
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, gcClear,
+ old0->x, old0->y, old1->x, old1->y);
XDrawLine(dpy, window, gcDraw,
new0->x, new0->y, new1->x, new1->y);
++old0;
static void
animateLMorph(void)
{
+ int i;
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;
- }
+ nFrom = nTo;
+ nTo = nNext;
+ aFrom = a[nFrom];
+ aTo = a[nTo];
do {
- nTo = RND(numFigs);
- } while (nTo == nFrom);
- aTo = a[nTo];
+ nNext = RND(numFigs);
+ } while (nNext == nTo);
+ aNext = a[nNext];
+
+ shift = RND(numPoints);
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;
+ p = aNext[i1];
+ aNext[i1] = aNext[i2];
+ aNext[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 */
+
+ /* calculate the slopes */
+ for (i = 0; i < numPoints ; i++) {
+ aSlopeFrom[i].x = aSlopeTo[i].x;
+ aSlopeFrom[i].y = aSlopeTo[i].y;
+ aSlopeTo[i].x = aNext[i].x - aTo[i].x;
+ aSlopeTo[i].y = (aNext[i].y - aTo[i].y);
+ }
}
createPoints();
currGamma += deltaGamma;
}
-
-
-/**************************************************************************
- * *
- * P U B L I C F U N C T I O N S *
- * *
- **************************************************************************/
+/*-----------------------------------------------------------------------+
+| PUBLIC FUNCTIONS |
++-----------------------------------------------------------------------*/
void
screenhack(Display *disp, Window win)
window = win;
initLMorph();
for (;;) {
- animateLMorph();
+ animateLMorph();
screenhack_handle_events (dpy);
usleep(delay);
- }
+ }
+
}
projects / xscreensaver / blobdiff