1 /* lavalite --- 3D Simulation a Lava Lite, written by jwz.
3 * This software Copyright (c) 2002-2014 Jamie Zawinski <jwz@jwz.org>
5 * Permission to use, copy, modify, distribute, and sell this software and its
6 * documentation for any purpose is hereby granted without fee, provided that
7 * the above copyright notice appear in all copies and that both that
8 * copyright notice and this permission notice appear in supporting
9 * documentation. No representations are made about the suitability of this
10 * software for any purpose. It is provided "as is" without express or
13 * LAVA®, LAVA LITE®, LAVA WORLD INTERNATIONAL® and the configuration of the
14 * LAVA® brand motion lamp are registered trademarks of Haggerty Enterprises,
15 * Inc. The configuration of the globe and base of the motion lamp are
16 * registered trademarks of Haggerty Enterprises, Inc. in the U.S.A. and in
17 * other countries around the world.
19 * Official Lava Lite web site: http://www.lavaworld.com/
21 * Implementation details:
23 * The blobs are generated using metaballs. For an explanation of what
24 * those are, see http://astronomy.swin.edu.au/~pbourke/modelling/implicitsurf/
25 * or http://www.fifi.org/doc/povray-manual/pov30005.htm
27 * Basically, each bubble of lava is a few (4) overlapping spherical metaballs
28 * of various sizes following similar but slightly different steep, slow
29 * parabolic arcs from the bottom to the top and back.
31 * We then polygonize the surface of the lava using the marching squares
32 * algorithm implemented in marching.c.
34 * Like real lavalites, this program is very slow.
36 * Surprisingly, it's loading the CPU and not the graphics engine: the speed
37 * bottleneck is in *computing* the scene rather than *rendering* it. We
38 * actually don't use a huge number of polygons, but computing the mesh for
39 * the surface takes a lot of cycles.
41 * I eliminated all the square roots, but there is still a lot of
42 * floating-point multiplication in here. I tried optimizing away the
43 * fp divisions, but that didn't seem to make a difference.
45 * -style lamp shape: classic, giant, cone, rocket, or random.
46 * -speed frequency at which new blobs launch.
47 * -resolution density of the polygon mesh.
48 * -count max number of blobs allowed at once.
49 * -wander, -spin whether to roll the scene around the screen.
50 * -lava-color color of the blobbies
51 * -fluid-color color of the stuff the blobbies float in
52 * -base-color color of the base of the lamp
53 * -table-color color of the table under the lamp
54 * -impatient at startup, skip forward in the animation so
55 * that at least one blob is fully exposed.
59 * - make the table look better, somehow.
60 * - should the lava be emissive? should the one at the bottom be
61 * more brightly colored than the ones at the top? light distance?
62 * - is there some way to put a specular reflection on the front glass
63 * itself? Maybe render it twice with FRONT/BACK tweaked, or alpha
64 * with depth buffering turned off?
67 #define DEFAULTS "*delay: 30000 \n" \
68 "*showFPS: False \n" \
69 "*wireframe: False \n" \
70 "*geometry: 600x900\n" \
71 "*count: " DEF_COUNT " \n" \
73 # define refresh_lavalite 0
74 # define release_lavalite 0
77 #define BLOBS_PER_GROUP 4
79 #define GRAVITY 0.000013 /* odwnward acceleration */
80 #define CONVECTION 0.005 /* initial upward velocity (bell curve) */
81 #define TILT 0.00166666 /* horizontal velocity (bell curve) */
84 #define countof(x) (sizeof((x))/sizeof((*x)))
87 #define ABS(n) ((n)<0?-(n):(n))
89 #define SIGNOF(n) ((n)<0?-1:1)
91 #include "xlockmore.h"
94 #include "gltrackball.h"
95 #include "xpm-ximage.h"
98 #ifdef USE_GL /* whole file */
102 #define DEF_WANDER "False"
103 #define DEF_SPEED "0.003"
104 #define DEF_RESOLUTION "40"
105 #define DEF_SMOOTH "True"
106 #define DEF_COUNT "3"
107 #define DEF_STYLE "random"
108 #define DEF_IMPATIENT "False"
109 #define DEF_LCOLOR "#FF0000" /* lava */
110 #define DEF_FCOLOR "#00AAFF" /* fluid */
111 #define DEF_BCOLOR "#666666" /* base */
112 #define DEF_TCOLOR "#000000" /*"#00FF00"*/ /* table */
114 #define DEF_FTEX "(none)"
115 #define DEF_BTEX "(none)"
116 #define DEF_TTEX "(none)"
118 typedef struct metaball metaball;
125 double r; /* hard radius */
126 double R; /* radius of field of influence */
128 double z; /* vertical position */
129 double pos_r; /* position on horizontal circle */
130 double pos_th; /* position on horizontal circle */
131 double dr, dz; /* current velocity */
133 double x, y; /* h planar position - compused from the above */
135 metaball *leader; /* stay close to this other ball */
139 typedef enum { CLASSIC = 0, GIANT, CONE, ROCKET } lamp_style;
140 typedef enum { CAP = 100, BOTTLE, BASE } lamp_part;
146 GLfloat texture_elevation;
149 static const lamp_geometry classic_lamp[] = {
150 { CAP, 1.16, 0.089, 0.00 },
151 { BOTTLE, 0.97, 0.120, 0.40 },
152 { BOTTLE, 0.13, 0.300, 0.87 },
153 { BOTTLE, 0.07, 0.300, 0.93 },
154 { BASE, 0.00, 0.280, 0.00 },
155 { BASE, -0.40, 0.120, 0.50 },
156 { BASE, -0.80, 0.280, 1.00 },
160 static const lamp_geometry giant_lamp[] = {
161 { CAP, 1.12, 0.105, 0.00 },
162 { BOTTLE, 0.97, 0.130, 0.30 },
163 { BOTTLE, 0.20, 0.300, 0.87 },
164 { BOTTLE, 0.15, 0.300, 0.93 },
165 { BASE, 0.00, 0.230, 0.00 },
166 { BASE, -0.18, 0.140, 0.20 },
167 { BASE, -0.80, 0.280, 1.00 },
171 static const lamp_geometry cone_lamp[] = {
172 { CAP, 1.35, 0.001, 0.00 },
173 { CAP, 1.35, 0.020, 0.00 },
174 { CAP, 1.30, 0.055, 0.05 },
175 { BOTTLE, 0.97, 0.120, 0.40 },
176 { BOTTLE, 0.13, 0.300, 0.87 },
177 { BASE, 0.00, 0.300, 0.00 },
178 { BASE, -0.04, 0.320, 0.04 },
179 { BASE, -0.60, 0.420, 0.50 },
183 static const lamp_geometry rocket_lamp[] = {
184 { CAP, 1.35, 0.001, 0.00 },
185 { CAP, 1.34, 0.020, 0.00 },
186 { CAP, 1.30, 0.055, 0.05 },
187 { BOTTLE, 0.97, 0.120, 0.40 },
188 { BOTTLE, 0.13, 0.300, 0.87 },
189 { BOTTLE, 0.07, 0.300, 0.93 },
190 { BASE, 0.00, 0.280, 0.00 },
191 { BASE, -0.50, 0.180, 0.50 },
192 { BASE, -0.75, 0.080, 0.75 },
193 { BASE, -0.80, 0.035, 0.80 },
194 { BASE, -0.90, 0.035, 1.00 },
201 GLXContext *glx_context;
203 const lamp_geometry *model;
206 trackball_state *trackball;
209 GLfloat max_bottle_radius; /* radius of widest part of the bottle */
211 GLfloat launch_chance; /* how often to percolate */
212 int blobs_per_group; /* how many metaballs we launch at once */
213 Bool just_started_p; /* so we launch some goo right away */
215 int grid_size; /* resolution for marching-cubes */
222 int bottle_poly_count; /* polygons in the bottle only */
224 } lavalite_configuration;
226 static lavalite_configuration *bps = NULL;
228 static char *do_spin;
229 static char *do_style;
230 static GLfloat speed;
231 static Bool do_wander;
232 static int resolution;
233 static Bool do_smooth;
234 static Bool do_impatient;
236 static char *lava_color_str, *fluid_color_str, *base_color_str,
238 static char *fluid_tex, *base_tex, *table_tex;
240 static GLfloat lava_color[4], fluid_color[4], base_color[4], table_color[4];
242 static const GLfloat lava_spec[4] = {1.0, 1.0, 1.0, 1.0};
243 static const GLfloat lava_shininess = 128.0;
244 static const GLfloat foot_color[4] = {0.2, 0.2, 0.2, 1.0};
246 static const GLfloat light0_pos[4] = {-0.6, 0.0, 1.0, 0.0};
247 static const GLfloat light1_pos[4] = { 1.0, 0.0, 0.2, 0.0};
248 static const GLfloat light2_pos[4] = { 0.6, 0.0, 1.0, 0.0};
252 static XrmOptionDescRec opts[] = {
253 { "-style", ".style", XrmoptionSepArg, 0 },
254 { "-spin", ".spin", XrmoptionSepArg, 0 },
255 { "+spin", ".spin", XrmoptionNoArg, "" },
256 { "-speed", ".speed", XrmoptionSepArg, 0 },
257 { "-wander", ".wander", XrmoptionNoArg, "True" },
258 { "+wander", ".wander", XrmoptionNoArg, "False" },
259 { "-resolution", ".resolution", XrmoptionSepArg, 0 },
260 { "-smooth", ".smooth", XrmoptionNoArg, "True" },
261 { "+smooth", ".smooth", XrmoptionNoArg, "False" },
262 { "-impatient", ".impatient", XrmoptionNoArg, "True" },
263 { "+impatient", ".impatient", XrmoptionNoArg, "False" },
265 { "-lava-color", ".lavaColor", XrmoptionSepArg, 0 },
266 { "-fluid-color", ".fluidColor", XrmoptionSepArg, 0 },
267 { "-base-color", ".baseColor", XrmoptionSepArg, 0 },
268 { "-table-color", ".tableColor", XrmoptionSepArg, 0 },
270 { "-fluid-texture",".fluidTexture", XrmoptionSepArg, 0 },
271 { "-base-texture", ".baseTexture", XrmoptionSepArg, 0 },
272 { "-table-texture",".tableTexture", XrmoptionSepArg, 0 },
275 static argtype vars[] = {
276 {&do_style, "style", "Style", DEF_STYLE, t_String},
277 {&do_spin, "spin", "Spin", DEF_SPIN, t_String},
278 {&do_wander, "wander", "Wander", DEF_WANDER, t_Bool},
279 {&speed, "speed", "Speed", DEF_SPEED, t_Float},
280 {&resolution, "resolution", "Resolution", DEF_RESOLUTION, t_Int},
281 {&do_smooth, "smooth", "Smooth", DEF_SMOOTH, t_Bool},
282 {&do_impatient, "impatient", "Impatient", DEF_IMPATIENT, t_Bool},
284 {&lava_color_str, "lavaColor", "LavaColor", DEF_LCOLOR, t_String},
285 {&fluid_color_str, "fluidColor", "FluidColor", DEF_FCOLOR, t_String},
286 {&base_color_str, "baseColor", "BaseColor", DEF_BCOLOR, t_String},
287 {&table_color_str, "tableColor", "TableColor", DEF_TCOLOR, t_String},
289 {&fluid_tex, "fluidTexture", "FluidTexture", DEF_FTEX, t_String},
290 {&base_tex, "baseTexture", "BaseTexture", DEF_BTEX, t_String},
291 {&table_tex, "tableTexture", "BaseTexture", DEF_TTEX, t_String},
294 ENTRYPOINT ModeSpecOpt lavalite_opts = {countof(opts), opts, countof(vars), vars, NULL};
297 /* Window management, etc
300 reshape_lavalite (ModeInfo *mi, int width, int height)
302 GLfloat h = (GLfloat) height / (GLfloat) width;
304 glViewport (0, 0, (GLint) width, (GLint) height);
306 glMatrixMode(GL_PROJECTION);
308 gluPerspective (30.0, 1/h, 1.0, 100.0);
310 glMatrixMode(GL_MODELVIEW);
312 gluLookAt( 0.0, 0.0, 30.0,
316 glClear(GL_COLOR_BUFFER_BIT);
325 load_texture (ModeInfo *mi, const char *filename)
327 Display *dpy = mi->dpy;
328 Visual *visual = mi->xgwa.visual;
329 Colormap cmap = mi->xgwa.colormap;
335 !strcasecmp (filename, "(none)"))
337 glDisable (GL_TEXTURE_2D);
341 image = xpm_file_to_ximage (dpy, visual, cmap, filename);
344 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
345 image->width, image->height, 0,
346 GL_RGBA, GL_UNSIGNED_BYTE, image->data);
347 sprintf (buf, "texture: %.100s (%dx%d)",
348 filename, image->width, image->height);
351 glPixelStorei (GL_UNPACK_ALIGNMENT, 4);
352 glPixelStorei (GL_UNPACK_ROW_LENGTH, image->width);
353 glTexEnvf (GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
354 glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
355 glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
356 glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
357 glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
359 glEnable (GL_TEXTURE_2D);
365 /* Generating the lamp's bottle, caps, and base.
369 draw_disc (GLfloat r, GLfloat z, int faces, Bool up_p, Bool wire)
373 GLfloat step = M_PI * 2 / faces;
377 glFrontFace (up_p ? GL_CW : GL_CCW);
378 glNormal3f (0, (up_p ? 1 : -1), 0);
379 glBegin (wire ? GL_LINE_LOOP : GL_TRIANGLES);
384 for (j = 0, th = 0; j <= faces; j++)
386 glTexCoord2f (-j / (GLfloat) faces, 1);
387 glVertex3f (0, z, 0);
389 glTexCoord2f (-j / (GLfloat) faces, 0);
390 glVertex3f (x, z, y);
396 glTexCoord2f (-j / (GLfloat) faces, 0);
397 glVertex3f (x, z, y);
408 draw_tube (GLfloat r0, GLfloat r1,
409 GLfloat z0, GLfloat z1,
410 GLfloat t0, GLfloat t1,
411 int faces, Bool inside_out_p, Bool smooth_p, Bool wire)
415 GLfloat x, y, x0=0, y0=0;
416 GLfloat step = M_PI * 2 / faces;
420 glFrontFace (inside_out_p ? GL_CW : GL_CCW);
421 glBegin (wire ? GL_LINES : (smooth_p ? GL_QUAD_STRIP : GL_QUADS));
433 if (smooth_p) faces++;
435 for (i = 0; i < faces; i++)
437 int nsign = (inside_out_p ? -1 : 1);
440 glNormal3f (x * nsign, z1, y * nsign);
442 glNormal3f (x0 * nsign, z1, y0 * nsign);
444 glTexCoord2f (nsign * -i / (GLfloat) faces, 1-t1);
445 glVertex3f (x * r1, z1, y * r1);
447 glTexCoord2f (nsign * -i / (GLfloat) faces, 1-t0);
448 glVertex3f (x * r0, z0, y * r0);
459 glTexCoord2f (nsign * -(i+1) / (double) faces, 1-t0);
460 glVertex3f (x * r0, z0, y * r0);
462 glTexCoord2f (nsign * -(i+1) / (double) faces, 1-t1);
463 glVertex3f (x * r1, z1, y * r1);
475 draw_table (GLfloat z, Bool wire)
478 GLfloat step = M_PI * 2 / faces;
484 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, table_color);
488 glBegin(wire ? GL_LINE_LOOP : GL_TRIANGLE_FAN);
492 glTexCoord2f (-0.5, 0.5);
496 for (j = 0, th = 0; j <= faces; j++)
498 GLfloat x = cos (th);
499 GLfloat y = sin (th);
500 glTexCoord2f (-(x+1)/2.0, (y+1)/2.0);
501 glVertex3f(x*s, z, y*s);
511 draw_wing (GLfloat w, GLfloat h, GLfloat d, Bool wire)
513 static const int coords[2][8][2] = {
534 int maxx = coords[0][countof(coords[0])-1][0];
535 int maxy = coords[0][countof(coords[0])-1][1];
538 for (x = 1; x < countof(coords[0]); x++)
540 GLfloat px0 = (GLfloat) coords[0][x-1][0] / maxx * w;
541 GLfloat py0 = (GLfloat) coords[0][x-1][1] / maxy * h;
542 GLfloat px1 = (GLfloat) coords[1][x-1][0] / maxx * w;
543 GLfloat py1 = (GLfloat) coords[1][x-1][1] / maxy * h;
544 GLfloat px2 = (GLfloat) coords[0][x ][0] / maxx * w;
545 GLfloat py2 = (GLfloat) coords[0][x ][1] / maxy * h;
546 GLfloat px3 = (GLfloat) coords[1][x ][0] / maxx * w;
547 GLfloat py3 = (GLfloat) coords[1][x ][1] / maxy * h;
553 glNormal3f (0, 0, -1);
554 glBegin (wire ? GL_LINE_LOOP : GL_QUADS);
556 glTexCoord2f (px0, py0); glVertex3f (px0, -py0, -zz);
557 glTexCoord2f (px1, py1); glVertex3f (px1, -py1, -zz);
558 glTexCoord2f (px3, py3); glVertex3f (px3, -py3, -zz);
559 glTexCoord2f (px2, py2); glVertex3f (px2, -py2, -zz);
565 glFrontFace (GL_CCW);
566 glNormal3f (0, 0, -1);
567 glBegin (wire ? GL_LINE_LOOP : GL_QUADS);
568 glTexCoord2f(px0, py0); glVertex3f (px0, -py0, zz);
569 glTexCoord2f(px1, py1); glVertex3f (px1, -py1, zz);
570 glTexCoord2f(px3, py3); glVertex3f (px3, -py3, zz);
571 glTexCoord2f(px2, py2); glVertex3f (px2, -py2, zz);
577 glFrontFace (GL_CCW);
578 glNormal3f (1, -1, 0); /* #### wrong */
579 glBegin (wire ? GL_LINE_LOOP : GL_QUADS);
580 glTexCoord2f(px0, py0); glVertex3f (px0, -py0, -zz);
581 glTexCoord2f(px0, py0); glVertex3f (px0, -py0, zz);
582 glTexCoord2f(px2, py2); glVertex3f (px2, -py2, zz);
583 glTexCoord2f(px2, py2); glVertex3f (px2, -py2, -zz);
590 glNormal3f (-1, 1, 0); /* #### wrong */
591 glBegin (wire ? GL_LINE_LOOP : GL_QUADS);
592 glTexCoord2f(px1, py1); glVertex3f (px1, -py1, -zz);
593 glTexCoord2f(px1, py1); glVertex3f (px1, -py1, zz);
594 glTexCoord2f(px3, py3); glVertex3f (px3, -py3, zz);
595 glTexCoord2f(px3, py3); glVertex3f (px3, -py3, -zz);
608 generate_bottle (ModeInfo *mi)
610 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
611 int wire = MI_IS_WIREFRAME(mi);
612 int faces = resolution * 1.5;
613 Bool smooth = do_smooth;
615 const lamp_geometry *top_slice = bp->model;
616 const char *current_texture = 0;
617 lamp_part last_part = 0;
619 if (faces < 3) faces = 3;
620 else if (wire && faces > 20) faces = 20;
621 else if (faces > 60) faces = 60;
623 bp->bottle_poly_count = 0;
625 glNewList (bp->bottle_list, GL_COMPILE);
628 glRotatef (90, 1, 0, 0);
629 glTranslatef (0, -0.5, 0);
631 /* All parts of the lamp use the same specularity and shininess. */
632 glMaterialfv (GL_FRONT, GL_SPECULAR, lava_spec);
633 glMateriali (GL_FRONT, GL_SHININESS, lava_shininess);
637 const lamp_geometry *bot_slice = top_slice + 1;
639 const char *texture = 0;
643 glDisable (GL_LIGHT2);
645 switch (top_slice->part)
655 if (!wire) glEnable (GL_LIGHT2); /* light2 affects only fluid */
662 if (!wire && texture && texture != current_texture)
664 current_texture = texture;
665 load_texture (mi, current_texture);
668 /* Color the discs darker than the tube walls. */
669 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, foot_color);
671 /* Do a top disc if this is the first slice of the CAP or BASE.
673 if ((top_slice->part == CAP && last_part == 0) ||
674 (top_slice->part == BASE && last_part == BOTTLE))
675 bp->bottle_poly_count +=
676 draw_disc (top_slice->radius, top_slice->elevation, faces,
679 /* Do a bottom disc if this is the last slice of the CAP or BASE.
681 if ((top_slice->part == CAP && bot_slice->part == BOTTLE) ||
682 (top_slice->part == BASE && bot_slice->part == 0))
684 const lamp_geometry *sl = (bot_slice->part == 0
685 ? top_slice : bot_slice);
686 bp->bottle_poly_count +=
687 draw_disc (sl->radius, sl->elevation, faces, False, wire);
690 if (bot_slice->part == 0) /* done! */
695 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color);
697 t0 = top_slice->texture_elevation;
698 t1 = bot_slice->texture_elevation;
700 /* Restart the texture coordinates for the glass.
702 if (top_slice->part == BOTTLE)
704 Bool first_p = (top_slice[-1].part != BOTTLE);
705 Bool last_p = (bot_slice->part != BOTTLE);
710 bp->bottle_poly_count +=
711 draw_tube (top_slice->radius, bot_slice->radius,
712 top_slice->elevation, bot_slice->elevation,
715 (top_slice->part == BOTTLE),
718 last_part = top_slice->part;
722 if (bp->style == ROCKET)
725 for (i = 0; i < 3; i++)
728 glRotatef (120 * i, 0, 1, 0);
729 glTranslatef (0.14, -0.05, 0);
730 bp->bottle_poly_count += draw_wing (0.4, 0.95, 0.02, wire);
733 glTranslatef (0, -0.1, 0); /* move floor down a little */
737 if (!wire) load_texture (mi, table_tex);
738 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, table_color);
739 bp->bottle_poly_count += draw_table (top_slice->elevation, wire);
743 glDisable (GL_TEXTURE_2D); /* done with textured objects */
750 /* Generating blobbies
754 bellrand (double extent) /* like frand(), but a bell curve. */
756 return (((frand(extent) + frand(extent) + frand(extent)) / 3)
761 static void move_ball (ModeInfo *mi, metaball *b);
763 /* Bring a ball into play, and re-randomize its values.
766 reset_ball (ModeInfo *mi, metaball *b)
768 /* lavalite_configuration *bp = &bps[MI_SCREEN(mi)]; */
771 b->R = 0.12 + bellrand(0.10);
773 b->pos_r = bellrand (0.9);
774 b->pos_th = frand(M_PI*2);
777 b->dr = bellrand(TILT);
789 /* returns the first metaball that is not in use, or 0.
792 get_ball (ModeInfo *mi)
794 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
796 for (i = 0; i < bp->nballs; i++)
798 metaball *b = &bp->balls[i];
806 /* Generate the blobs that don't move: the ones at teh top and bottom
807 that are part of the scenery.
810 generate_static_blobs (ModeInfo *mi)
812 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
823 /* the giant blob at the bottom of the bottle.
833 /* the small blob at the top of the bottle.
843 /* Some extra blobs at the bottom of the bottle, to jumble the surface.
845 for (i = 0; i < bp->blobs_per_group; i++)
859 max_bottle_radius (lavalite_configuration *bp)
862 const lamp_geometry *slice;
863 for (slice = bp->model; slice->part != 0; slice++)
865 if (slice->part == BOTTLE && slice->radius > r)
866 r = slice->radius; /* top */
867 if (slice[1].radius > r)
868 r = slice[1].radius; /* bottom */
875 bottle_radius_at (lavalite_configuration *bp, GLfloat z)
877 GLfloat topz = -999, botz = -999, topr = 0, botr = 0;
878 const lamp_geometry *slice;
881 for (slice = bp->model; slice->part != 0; slice++)
882 if (z > slice->elevation)
885 topz = slice->elevation;
886 topr = slice->radius;
889 if (topz == -999) return 0;
891 for (; slice->part != 0; slice++)
892 if (z > slice->elevation)
894 botz = slice->elevation;
895 botr = slice->radius;
898 if (botz == -999) return 0;
900 ratio = (z - botz) / (topz - botz);
902 return (botr + ((topr - botr) * ratio));
907 move_ball (ModeInfo *mi, metaball *b)
909 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
910 double gravity = GRAVITY;
913 if (b->static_p) return;
925 else if (b->pos_r < 0)
927 b->pos_r = -b->pos_r;
931 real_r = b->pos_r * bottle_radius_at (bp, b->z);
933 b->x = cos (b->pos_th) * real_r;
934 b->y = sin (b->pos_th) * real_r;
936 if (b->z < -b->R) /* dropped below bottom of glass - turn it off */
941 /* This function makes sure that balls that are part of a group always stay
942 relatively close to each other.
945 clamp_balls (ModeInfo *mi)
947 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
949 for (i = 0; i < bp->nballs; i++)
951 metaball *b = &bp->balls[i];
952 if (b->alive_p && b->leader)
955 double minz = b->leader->z - zslack;
956 double maxz = b->leader->z + zslack;
958 /* Try to keep the Z values near those of the leader.
959 Don't let it go out of range (above or below) and clamp it
960 if it does. If we've clamped it, make sure dz will be
961 moving it in the right direction (back toward the leader.)
963 We aren't currently clamping r, only z -- doesn't seem to
966 This is kind of flaky, I think. Sometimes you can see
967 the blobbies "twitch". That's no good.
972 if (b->dz < 0) b->dz = -b->dz;
978 if (b->dz > 0) b->dz = -b->dz;
987 move_balls (ModeInfo *mi) /* for great justice */
989 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
991 for (i = 0; i < bp->nballs; i++)
993 metaball *b = &bp->balls[i];
1003 /* Rendering blobbies using marching cubes.
1007 compute_metaball_influence (lavalite_configuration *bp,
1008 double x, double y, double z,
1009 int nballs, metaball *balls)
1014 for (i = 0; i < nballs; i++)
1016 metaball *b = &balls[i];
1018 double d2, r, R, r2, R2;
1020 if (!b->alive_p) continue;
1027 if (dx > R || dx < -R || /* quick check before multiplying */
1028 dy > R || dy < -R ||
1032 d2 = (dx*dx + dy*dy + dz*dz);
1038 if (d2 <= r2) /* (d <= r) inside the hard radius */
1040 else if (d2 > R2) /* (d > R) outside the radius of influence */
1042 else /* somewhere in between: linear drop-off from r=1 to R=0 */
1044 /* was: vv += 1 - ((d-r) / (R-r)); */
1045 vv += 1 - ((d2-r2) / (R2-r2));
1053 /* callback for marching_cubes() */
1055 obj_init (double grid_size, void *closure)
1057 lavalite_configuration *bp = (lavalite_configuration *) closure;
1058 bp->grid_size = grid_size;
1064 /* Returns True if the given point is outside of the glass tube.
1067 clipped_by_glass_p (double x, double y, double z,
1068 lavalite_configuration *bp)
1070 double d2, or, or2, ir2;
1072 or = bp->max_bottle_radius;
1074 if (x > or || x < -or || /* quick check before multiplying */
1079 or = bottle_radius_at (bp, z);
1083 if (d2 > or2) /* (sqrt(d) > or) */
1088 if (d2 > ir2) /* (sqrt(d) > ir) */
1092 /* was: (1 - (d-ratio2) / (ratio1-ratio2)) */
1093 return (1 - (d2-dr2) / (dr1-dr2));
1101 /* callback for marching_cubes() */
1103 obj_compute (double x, double y, double z, void *closure)
1105 lavalite_configuration *bp = (lavalite_configuration *) closure;
1108 x /= bp->grid_size; /* convert from 0-N to 0-1. */
1112 x -= 0.5; /* X and Y range from -.5 to +.5; z ranges from 0-1. */
1115 clip = clipped_by_glass_p (x, y, z, bp);
1116 if (clip == 0) return 0;
1119 compute_metaball_influence (bp, x, y, z, bp->nballs, bp->balls));
1123 /* callback for marching_cubes() */
1125 obj_free (void *closure)
1130 /* Send a new blob travelling upward.
1131 This blob will actually be composed of N metaballs that are near
1135 launch_balls (ModeInfo *mi)
1137 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
1138 metaball *b0 = get_ball (mi);
1142 reset_ball (mi, b0);
1144 for (i = 0; i < bp->blobs_per_group; i++)
1146 metaball *b1 = get_ball (mi);
1150 reset_ball (mi, b1);
1153 # define FROB(FIELD,AMT) \
1154 b1->FIELD += (bellrand(AMT) * b0->FIELD)
1156 /* FROB (pos_r, 0.7); */
1157 /* FROB (pos_th, 0.7); */
1167 animate_lava (ModeInfo *mi)
1169 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
1170 int wire = MI_IS_WIREFRAME(mi);
1171 Bool just_started_p = bp->just_started_p;
1173 double isolevel = 0.3;
1175 /* Maybe bubble a new blobby to the surface.
1177 if (just_started_p ||
1178 frand(1.0) < bp->launch_chance)
1180 bp->just_started_p = False;
1183 if (do_impatient && just_started_p)
1188 for (i = 0; i < bp->nballs; i++)
1190 metaball *b = &bp->balls[i];
1191 if (b->alive_p && !b->static_p && !b->leader &&
1201 glNewList (bp->ball_list, GL_COMPILE);
1204 glMaterialfv (GL_FRONT, GL_SPECULAR, lava_spec);
1205 glMateriali (GL_FRONT, GL_SHININESS, lava_shininess);
1206 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, lava_color);
1208 /* For the blobbies, the origin is on the axis at the bottom of the
1209 glass bottle; and the top of the bottle is +1 on Z.
1211 glTranslatef (0, 0, -0.5);
1213 mi->polygon_count = 0;
1216 if (bp->grid_size == 0) bp->grid_size = 1; /* first time through */
1217 s = 1.0/bp->grid_size;
1220 glTranslatef (-0.5, -0.5, 0);
1222 marching_cubes (resolution, isolevel, wire, do_smooth,
1223 obj_init, obj_compute, obj_free, bp,
1224 &mi->polygon_count);
1228 mi->polygon_count += bp->bottle_poly_count;
1236 /* Startup initialization
1240 lavalite_handle_event (ModeInfo *mi, XEvent *event)
1242 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
1244 if (gltrackball_event_handler (event, bp->trackball,
1245 MI_WIDTH (mi), MI_HEIGHT (mi),
1246 &bp->button_down_p))
1254 parse_color (ModeInfo *mi, const char *name, const char *s, GLfloat *a)
1257 a[3] = 1.0; /* alpha */
1259 if (! XParseColor (MI_DISPLAY(mi), MI_COLORMAP(mi), s, &c))
1261 fprintf (stderr, "%s: can't parse %s color %s", progname, name, s);
1264 a[0] = c.red / 65536.0;
1265 a[1] = c.green / 65536.0;
1266 a[2] = c.blue / 65536.0;
1271 init_lavalite (ModeInfo *mi)
1273 lavalite_configuration *bp;
1274 int wire = MI_IS_WIREFRAME(mi);
1277 bps = (lavalite_configuration *)
1278 calloc (MI_NUM_SCREENS(mi), sizeof (lavalite_configuration));
1280 fprintf(stderr, "%s: out of memory\n", progname);
1285 bp = &bps[MI_SCREEN(mi)];
1287 bp->glx_context = init_GL(mi);
1289 reshape_lavalite (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
1293 if (!s || !*s || !strcasecmp (s, "classic")) bp->style = CLASSIC;
1294 else if (!strcasecmp (s, "giant")) bp->style = GIANT;
1295 else if (!strcasecmp (s, "cone")) bp->style = CONE;
1296 else if (!strcasecmp (s, "rocket")) bp->style = ROCKET;
1297 else if (!strcasecmp (s, "random"))
1299 if (random() & 1) bp->style = CLASSIC; /* half the time */
1300 else bp->style = (random() % ((int) ROCKET+1));
1305 "%s: style must be Classic, Giant, Cone, or Rocket (not \"%s\")\n",
1311 parse_color (mi, "lava", lava_color_str, lava_color);
1312 parse_color (mi, "fluid", fluid_color_str, fluid_color);
1313 parse_color (mi, "base", base_color_str, base_color);
1314 parse_color (mi, "table", table_color_str, table_color);
1318 GLfloat amb[4] = {0.0, 0.0, 0.0, 1.0};
1319 GLfloat dif[4] = {1.0, 1.0, 1.0, 1.0};
1320 GLfloat spc0[4] = {0.0, 1.0, 1.0, 1.0};
1321 GLfloat spc1[4] = {1.0, 0.0, 1.0, 1.0};
1323 glEnable(GL_LIGHTING);
1324 glEnable(GL_LIGHT0);
1325 glEnable(GL_LIGHT1);
1326 glEnable(GL_DEPTH_TEST);
1327 glEnable(GL_CULL_FACE);
1328 glEnable(GL_NORMALIZE);
1329 glShadeModel(GL_SMOOTH);
1331 glLightfv(GL_LIGHT0, GL_AMBIENT, amb);
1332 glLightfv(GL_LIGHT0, GL_DIFFUSE, dif);
1333 glLightfv(GL_LIGHT0, GL_SPECULAR, spc0);
1335 glLightfv(GL_LIGHT1, GL_AMBIENT, amb);
1336 glLightfv(GL_LIGHT1, GL_DIFFUSE, dif);
1337 glLightfv(GL_LIGHT1, GL_SPECULAR, spc1);
1339 glLightfv(GL_LIGHT2, GL_AMBIENT, amb);
1340 glLightfv(GL_LIGHT2, GL_DIFFUSE, dif);
1341 glLightfv(GL_LIGHT2, GL_SPECULAR, spc0);
1345 Bool spinx=False, spiny=False, spinz=False;
1346 double spin_speed = 0.4;
1347 double wander_speed = 0.03;
1352 if (*s == 'x' || *s == 'X') spinx = True;
1353 else if (*s == 'y' || *s == 'Y') spiny = True;
1354 else if (*s == 'z' || *s == 'Z') spinz = True;
1355 else if (*s == '0') ;
1359 "%s: spin must contain only the characters X, Y, or Z (not \"%s\")\n",
1366 bp->rot = make_rotator (spinx ? spin_speed : 0,
1367 spiny ? spin_speed : 0,
1368 spinz ? spin_speed : 0,
1370 do_wander ? wander_speed : 0,
1372 bp->rot2 = make_rotator (spin_speed, 0, 0,
1375 bp->trackball = gltrackball_init (False);
1377 /* move initial camera position up by around 15 degrees:
1378 in other words, tilt the scene toward the viewer. */
1379 gltrackball_start (bp->trackball, 50, 50, 100, 100);
1380 gltrackball_track (bp->trackball, 50, 5, 100, 100);
1382 /* Oh, but if it's the "Giant" model, tilt the scene away: make it
1383 look like we're looking up at it instead of down at it! */
1384 if (bp->style == GIANT)
1385 gltrackball_track (bp->trackball, 50, -12, 100, 100);
1386 else if (bp->style == ROCKET) /* same for rocket, but not as much */
1387 gltrackball_track (bp->trackball, 50, -4, 100, 100);
1392 case CLASSIC: bp->model = classic_lamp; break;
1393 case GIANT: bp->model = giant_lamp; break;
1394 case CONE: bp->model = cone_lamp; break;
1395 case ROCKET: bp->model = rocket_lamp; break;
1396 default: abort(); break;
1399 bp->max_bottle_radius = max_bottle_radius (bp);
1401 bp->launch_chance = speed;
1402 bp->blobs_per_group = BLOBS_PER_GROUP;
1403 bp->just_started_p = True;
1405 bp->nballs = (((MI_COUNT (mi) + 1) * bp->blobs_per_group)
1407 bp->balls = (metaball *) calloc (sizeof(*bp->balls), bp->nballs+1);
1409 bp->bottle_list = glGenLists (1);
1410 bp->ball_list = glGenLists (1);
1412 generate_bottle (mi);
1413 generate_static_blobs (mi);
1421 draw_lavalite (ModeInfo *mi)
1423 lavalite_configuration *bp = &bps[MI_SCREEN(mi)];
1424 Display *dpy = MI_DISPLAY(mi);
1425 Window window = MI_WINDOW(mi);
1427 if (!bp->glx_context)
1430 glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *(bp->glx_context));
1432 glMatrixMode (GL_MODELVIEW);
1436 double cx, cy, cz; /* camera position, 0-1. */
1437 double px, py, pz; /* object position, 0-1. */
1438 double rx, ry, rz; /* object rotation, 0-1. */
1440 get_position (bp->rot2, 0, &cy, &cz, !bp->button_down_p);
1441 get_rotation (bp->rot2, &cx, 0, 0, !bp->button_down_p);
1443 get_position (bp->rot, &px, &py, &pz, !bp->button_down_p);
1444 get_rotation (bp->rot, &rx, &ry, &rz, !bp->button_down_p);
1451 #else /* #### this crud doesn't really work yet */
1454 /* We have c[xyz] parameters describing a camera position, but we don't
1455 want to just map those to points in space: the lamp doesn't look very
1456 good from the inside, or from underneath...
1458 Good observation points form a ring around the lamp: basically, a
1459 torus ringing the lamp, parallel to the lamp's floor.
1461 We interpret cz as distance from the origin.
1463 cx is then used as position in the torus (theta).
1467 double cx2, cy2, cz2;
1474 cy2 = (cy * 0.4); /* cam elevation: 0.0 (table) - 0.4 up. */
1475 d = 0.9 + cz; /* cam distance: 0.9 - 1.9. */
1477 cz2 = 0.5 + (d * cos (cx * M_PI * 2));
1478 cx2 = 0.5 + (d * sin (cx * M_PI * 2));
1488 glRotatef(current_device_rotation(), 0, 0, 1);
1490 gluLookAt ((cx - 0.5) * 8, /* Position the camera */
1496 gltrackball_rotate (bp->trackball); /* Apply mouse-based camera position */
1498 /* Place the lights relative to the object, before the object has
1499 been rotated or wandered within the scene. */
1500 glLightfv(GL_LIGHT0, GL_POSITION, light0_pos);
1501 glLightfv(GL_LIGHT1, GL_POSITION, light1_pos);
1502 glLightfv(GL_LIGHT2, GL_POSITION, light2_pos);
1505 /* Position the lamp in the scene according to the "wander" settings */
1506 glTranslatef ((px - 0.5), (py - 0.5), (pz - 0.5));
1508 /* Rotate the object according to the "spin" settings */
1509 glRotatef (rx * 360, 1.0, 0.0, 0.0);
1510 glRotatef (ry * 360, 0.0, 1.0, 0.0);
1511 glRotatef (rz * 360, 0.0, 0.0, 1.0);
1513 /* Move the lamp up slightly: make 0,0 be at its vertical center. */
1516 case CLASSIC: glTranslatef (0, 0, 0.33); break;
1517 case GIANT: glTranslatef (0, 0, 0.33); break;
1518 case CONE: glTranslatef (0, 0, 0.16); break;
1519 case ROCKET: glTranslatef (0, 0, 0.30);
1520 glScalef (0.85,0.85,0.85); break;
1521 default: abort(); break;
1527 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
1528 glCallList (bp->bottle_list);
1529 glCallList (bp->ball_list);
1532 if (mi->fps_p) do_fps (mi);
1535 glXSwapBuffers(dpy, window);
1538 XSCREENSAVER_MODULE ("Lavalite", lavalite)