1 /* hypertorus --- Shows a hypertorus that rotates in 4d */
4 static const char sccsid[] = "@(#)hypertorus.c 1.2 05/09/28 xlockmore";
7 /* Copyright (c) 2003-2009 Carsten Steger <carsten@mirsanmir.org>. */
10 * Permission to use, copy, modify, and distribute this software and its
11 * documentation for any purpose and without fee is hereby granted,
12 * provided that the above copyright notice appear in all copies and that
13 * both that copyright notice and this permission notice appear in
14 * supporting documentation.
16 * This file is provided AS IS with no warranties of any kind. The author
17 * shall have no liability with respect to the infringement of copyrights,
18 * trade secrets or any patents by this file or any part thereof. In no
19 * event will the author be liable for any lost revenue or profits or
20 * other special, indirect and consequential damages.
23 * C. Steger - 03/05/18: Initial version
24 * C. Steger - 05/09/28: Added the spirals appearance mode
25 * and trackball support
26 * C. Steger - 07/01/23: Improved 4d trackball support
27 * C. Steger - 09/08/22: Removed check-config.pl warnings
31 * This program shows the Clifford torus as it rotates in 4d. The Clifford
32 * torus is a torus lies on the "surface" of the hypersphere in 4d. The
33 * program projects the 4d torus to 3d using either a perspective or an
34 * orthographic projection. Of the two alternatives, the perspecitve
35 * projection looks much more appealing. In orthographic projections the
36 * torus degenerates into a doubly covered cylinder for some angles. The
37 * projected 3d torus can then be projected to the screen either perspectively
38 * or orthographically. There are three display modes for the torus: mesh
39 * (wireframe), solid, or transparent. Furthermore, the appearance of the
40 * torus can be as a solid object or as a set of see-through bands or
41 * see-through spirals. Finally, the colors with with the torus is drawn can
42 * be set to either two-sided or to colorwheel. In the first case, the torus
43 * is drawn with red on the outside and green on the inside. This mode
44 * enables you to see that the torus turns inside-out as it rotates in 4d.
45 * The second mode draws the torus in a fully saturated color wheel. This
46 * gives a very nice effect when combined with the see-through bands or
47 * see-through spirals mode. The rotation speed for each of the six planes
48 * around which the torus rotates can be chosen. This program is very much
49 * inspired by Thomas Banchoff's book "Beyond the Third Dimension: Geometry,
50 * Computer Graphics, and Higher Dimensions", Scientific American Library,
55 #define M_PI 3.14159265358979323846
58 #define DISP_WIREFRAME 0
59 #define DISP_SURFACE 1
60 #define DISP_TRANSPARENT 2
62 #define APPEARANCE_SOLID 0
63 #define APPEARANCE_BANDS 1
64 #define APPEARANCE_SPIRALS 2
66 #define COLORS_TWOSIDED 0
67 #define COLORS_COLORWHEEL 1
69 #define DISP_3D_PERSPECTIVE 0
70 #define DISP_3D_ORTHOGRAPHIC 1
72 #define DISP_4D_PERSPECTIVE 0
73 #define DISP_4D_ORTHOGRAPHIC 1
75 #define DEF_DISPLAY_MODE "surface"
76 #define DEF_APPEARANCE "bands"
77 #define DEF_COLORS "colorwheel"
78 #define DEF_PROJECTION_3D "perspective"
79 #define DEF_PROJECTION_4D "perspective"
80 #define DEF_SPEEDWX "1.1"
81 #define DEF_SPEEDWY "1.3"
82 #define DEF_SPEEDWZ "1.5"
83 #define DEF_SPEEDXY "1.7"
84 #define DEF_SPEEDXZ "1.9"
85 #define DEF_SPEEDYZ "2.1"
88 # define DEFAULTS "*delay: 25000 \n" \
89 "*showFPS: False \n" \
91 # define refresh_hypertorus 0
92 # include "xlockmore.h" /* from the xscreensaver distribution */
93 #else /* !STANDALONE */
94 # include "xlock.h" /* from the xlockmore distribution */
95 #endif /* !STANDALONE */
99 # include <X11/keysym.h>
102 #include "gltrackball.h"
106 ModStruct hypertorus_description =
107 {"hypertorus", "init_hypertorus", "draw_hypertorus", "release_hypertorus",
108 "draw_hypertorus", "change_hypertorus", NULL, &hypertorus_opts,
109 25000, 1, 1, 1, 1.0, 4, "",
110 "Shows a hypertorus rotating in 4d", 0, NULL};
116 static int display_mode;
118 static int appearance;
119 static int num_spirals;
120 static char *color_mode;
122 static char *proj_3d;
123 static int projection_3d;
124 static char *proj_4d;
125 static int projection_4d;
126 static float speed_wx;
127 static float speed_wy;
128 static float speed_wz;
129 static float speed_xy;
130 static float speed_xz;
131 static float speed_yz;
133 static const float offset4d[4] = { 0.0, 0.0, 0.0, 2.0 };
134 static const float offset3d[4] = { 0.0, 0.0, -2.0, 0.0 };
137 static XrmOptionDescRec opts[] =
139 {"-mode", ".displayMode", XrmoptionSepArg, 0 },
140 {"-wireframe", ".displayMode", XrmoptionNoArg, "wireframe" },
141 {"-surface", ".displayMode", XrmoptionNoArg, "surface" },
142 {"-transparent", ".displayMode", XrmoptionNoArg, "transparent" },
143 {"-appearance", ".appearance", XrmoptionSepArg, 0 },
144 {"-solid", ".appearance", XrmoptionNoArg, "solid" },
145 {"-bands", ".appearance", XrmoptionNoArg, "bands" },
146 {"-spirals-1", ".appearance", XrmoptionNoArg, "spirals-1" },
147 {"-spirals-2", ".appearance", XrmoptionNoArg, "spirals-2" },
148 {"-spirals-4", ".appearance", XrmoptionNoArg, "spirals-4" },
149 {"-spirals-8", ".appearance", XrmoptionNoArg, "spirals-8" },
150 {"-spirals-16", ".appearance", XrmoptionNoArg, "spirals-16" },
151 {"-twosided", ".colors", XrmoptionNoArg, "twosided" },
152 {"-colorwheel", ".colors", XrmoptionNoArg, "colorwheel" },
153 {"-perspective-3d", ".projection3d", XrmoptionNoArg, "perspective" },
154 {"-orthographic-3d", ".projection3d", XrmoptionNoArg, "orthographic" },
155 {"-perspective-4d", ".projection4d", XrmoptionNoArg, "perspective" },
156 {"-orthographic-4d", ".projection4d", XrmoptionNoArg, "orthographic" },
157 {"-speed-wx", ".speedwx", XrmoptionSepArg, 0 },
158 {"-speed-wy", ".speedwy", XrmoptionSepArg, 0 },
159 {"-speed-wz", ".speedwz", XrmoptionSepArg, 0 },
160 {"-speed-xy", ".speedxy", XrmoptionSepArg, 0 },
161 {"-speed-xz", ".speedxz", XrmoptionSepArg, 0 },
162 {"-speed-yz", ".speedyz", XrmoptionSepArg, 0 }
165 static argtype vars[] =
167 { &mode, "displayMode", "DisplayMode", DEF_DISPLAY_MODE, t_String },
168 { &appear, "appearance", "Appearance", DEF_APPEARANCE, t_String },
169 { &color_mode, "colors", "Colors", DEF_COLORS, t_String },
170 { &proj_3d, "projection3d", "Projection3d", DEF_PROJECTION_3D, t_String },
171 { &proj_4d, "projection4d", "Projection4d", DEF_PROJECTION_4D, t_String },
172 { &speed_wx, "speedwx", "Speedwx", DEF_SPEEDWX, t_Float},
173 { &speed_wy, "speedwy", "Speedwy", DEF_SPEEDWY, t_Float},
174 { &speed_wz, "speedwz", "Speedwz", DEF_SPEEDWZ, t_Float},
175 { &speed_xy, "speedxy", "Speedxy", DEF_SPEEDXY, t_Float},
176 { &speed_xz, "speedxz", "Speedxz", DEF_SPEEDXZ, t_Float},
177 { &speed_yz, "speedyz", "Speedyz", DEF_SPEEDYZ, t_Float}
180 static OptionStruct desc[] =
182 { "-wireframe", "display the torus as a wireframe mesh" },
183 { "-surface", "display the torus as a solid surface" },
184 { "-transparent", "display the torus as a transparent surface" },
185 { "-solid", "display the torus as a solid object" },
186 { "-bands", "display the torus as see-through bands" },
187 { "-spirals-{1,2,4,8,16}", "display the torus as see-through spirals" },
188 { "-twosided", "display the torus with two colors" },
189 { "-colorwheel", "display the torus with a smooth color wheel" },
190 { "-perspective-3d", "project the torus perspectively from 3d to 2d" },
191 { "-orthographic-3d", "project the torus orthographically from 3d to 2d" },
192 { "-perspective-4d", "project the torus perspectively from 4d to 3d" },
193 { "-orthographic-4d", "project the torus orthographically from 4d to 3d" },
194 { "-speed-wx <arg>", "rotation speed around the wx plane" },
195 { "-speed-wy <arg>", "rotation speed around the wy plane" },
196 { "-speed-wz <arg>", "rotation speed around the wz plane" },
197 { "-speed-xy <arg>", "rotation speed around the xy plane" },
198 { "-speed-xz <arg>", "rotation speed around the xz plane" },
199 { "-speed-yz <arg>", "rotation speed around the yz plane" }
202 ENTRYPOINT ModeSpecOpt hypertorus_opts =
203 {sizeof opts / sizeof opts[0], opts, sizeof vars / sizeof vars[0], vars, desc};
208 GLXContext *glx_context;
209 /* 4D rotation angles */
210 float alpha, beta, delta, zeta, eta, theta;
211 /* Aspect ratio of the current window */
213 /* Trackball states */
214 trackball_state *trackballs[2];
215 int current_trackball;
222 static hypertorusstruct *hyper = (hypertorusstruct *) NULL;
225 /* Add a rotation around the wx-plane to the matrix m. */
226 static void rotatewx(float m[4][4], float phi)
244 /* Add a rotation around the wy-plane to the matrix m. */
245 static void rotatewy(float m[4][4], float phi)
263 /* Add a rotation around the wz-plane to the matrix m. */
264 static void rotatewz(float m[4][4], float phi)
282 /* Add a rotation around the xy-plane to the matrix m. */
283 static void rotatexy(float m[4][4], float phi)
301 /* Add a rotation around the xz-plane to the matrix m. */
302 static void rotatexz(float m[4][4], float phi)
320 /* Add a rotation around the yz-plane to the matrix m. */
321 static void rotateyz(float m[4][4], float phi)
339 /* Compute the rotation matrix m from the rotation angles. */
340 static void rotateall(float al, float be, float de, float ze, float et,
341 float th, float m[4][4])
357 /* Multiply two rotation matrices: o=m*n. */
358 static void mult_rotmat(float m[4][4], float n[4][4], float o[4][4])
368 o[i][j] += m[i][k]*n[k][j];
374 /* Compute a 4D rotation matrix from two unit quaternions. */
375 static void quats_to_rotmat(float p[4], float q[4], float m[4][4])
377 double al, be, de, ze, et, th;
378 double r00, r01, r02, r12, r22;
380 r00 = 1.0-2.0*(p[1]*p[1]+p[2]*p[2]);
381 r01 = 2.0*(p[0]*p[1]+p[2]*p[3]);
382 r02 = 2.0*(p[2]*p[0]-p[1]*p[3]);
383 r12 = 2.0*(p[1]*p[2]+p[0]*p[3]);
384 r22 = 1.0-2.0*(p[1]*p[1]+p[0]*p[0]);
386 al = atan2(-r12,r22)*180.0/M_PI;
387 be = atan2(r02,sqrt(r00*r00+r01*r01))*180.0/M_PI;
388 de = atan2(-r01,r00)*180.0/M_PI;
390 r00 = 1.0-2.0*(q[1]*q[1]+q[2]*q[2]);
391 r01 = 2.0*(q[0]*q[1]+q[2]*q[3]);
392 r02 = 2.0*(q[2]*q[0]-q[1]*q[3]);
393 r12 = 2.0*(q[1]*q[2]+q[0]*q[3]);
394 r22 = 1.0-2.0*(q[1]*q[1]+q[0]*q[0]);
396 et = atan2(-r12,r22)*180.0/M_PI;
397 th = atan2(r02,sqrt(r00*r00+r01*r01))*180.0/M_PI;
398 ze = atan2(-r01,r00)*180.0/M_PI;
400 rotateall(al,be,de,ze,et,-th,m);
404 /* Compute a fully saturated and bright color based on an angle. */
405 static void color(double angle)
411 if (colors != COLORS_COLORWHEEL)
415 angle = fmod(angle,2*M_PI);
417 angle = fmod(angle,-2*M_PI);
418 s = floor(angle/(M_PI/3));
419 t = angle/(M_PI/3)-s;
455 if (display_mode == DISP_TRANSPARENT)
460 glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT_AND_DIFFUSE,color);
464 /* Draw a hypertorus projected into 3D. Note that the spirals appearance
465 will only work correctly if numu and numv are set to 64 or any higher
466 power of 2. Similarly, the banded appearance will only work correctly
467 if numu and numv are divisible by 4. */
468 static int hypertorus(ModeInfo *mi, double umin, double umax, double vmin,
469 double vmax, int numu, int numv)
472 static const GLfloat mat_diff_red[] = { 1.0, 0.0, 0.0, 1.0 };
473 static const GLfloat mat_diff_green[] = { 0.0, 1.0, 0.0, 1.0 };
474 static const GLfloat mat_diff_trans_red[] = { 1.0, 0.0, 0.0, 0.7 };
475 static const GLfloat mat_diff_trans_green[] = { 0.0, 1.0, 0.0, 0.7 };
476 float p[3], pu[3], pv[3], n[3], mat[4][4];
477 int i, j, k, l, m, b, skew;
479 double cu, su, cv, sv;
480 double xx[4], xxu[4], xxv[4], x[4], xu[4], xv[4];
482 float q1[4], q2[4], r1[4][4], r2[4][4];
483 hypertorusstruct *hp = &hyper[MI_SCREEN(mi)];
485 rotateall(hp->alpha,hp->beta,hp->delta,hp->zeta,hp->eta,hp->theta,r1);
487 gltrackball_get_quaternion(hp->trackballs[0],q1);
488 gltrackball_get_quaternion(hp->trackballs[1],q2);
489 quats_to_rotmat(q1,q2,r2);
491 mult_rotmat(r2,r1,mat);
493 if (colors != COLORS_COLORWHEEL)
495 glColor3fv(mat_diff_red);
496 if (display_mode == DISP_TRANSPARENT)
498 glMaterialfv(GL_FRONT,GL_AMBIENT_AND_DIFFUSE,mat_diff_trans_red);
499 glMaterialfv(GL_BACK,GL_AMBIENT_AND_DIFFUSE,mat_diff_trans_green);
503 glMaterialfv(GL_FRONT,GL_AMBIENT_AND_DIFFUSE,mat_diff_red);
504 glMaterialfv(GL_BACK,GL_AMBIENT_AND_DIFFUSE,mat_diff_green);
511 for (i=0; i<numu; i++)
513 if ((appearance == APPEARANCE_BANDS ||
514 appearance == APPEARANCE_SPIRALS) && ((i & 3) >= 2))
516 if (display_mode == DISP_WIREFRAME)
517 glBegin(GL_QUAD_STRIP);
519 glBegin(GL_TRIANGLE_STRIP);
520 for (j=0; j<=numv; j++)
528 if (appearance == APPEARANCE_SPIRALS)
530 u += 4.0*skew/numv*v;
531 b = ((i/4)&(skew-1))*(numu/(4*skew));
532 color(ur*4*b/numu+umin);
561 r += mat[l][m]*xx[m];
562 s += mat[l][m]*xxu[m];
563 t += mat[l][m]*xxv[m];
569 if (projection_4d == DISP_4D_ORTHOGRAPHIC)
573 p[l] = (x[l]+offset4d[l])/1.5+offset3d[l];
580 s = x[3]+offset4d[3];
584 r = x[l]+offset4d[l];
585 p[l] = r/s+offset3d[l];
586 pu[l] = (xu[l]*s-r*xu[3])/t;
587 pv[l] = (xv[l]*s-r*xv[3])/t;
590 n[0] = pu[1]*pv[2]-pu[2]*pv[1];
591 n[1] = pu[2]*pv[0]-pu[0]*pv[2];
592 n[2] = pu[0]*pv[1]-pu[1]*pv[0];
593 t = sqrt(n[0]*n[0]+n[1]*n[1]+n[2]*n[2]);
609 static void init(ModeInfo *mi)
611 static const GLfloat light_ambient[] = { 0.0, 0.0, 0.0, 1.0 };
612 static const GLfloat light_diffuse[] = { 1.0, 1.0, 1.0, 1.0 };
613 static const GLfloat light_specular[] = { 1.0, 1.0, 1.0, 1.0 };
614 static const GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };
615 static const GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
616 hypertorusstruct *hp = &hyper[MI_SCREEN(mi)];
625 glMatrixMode(GL_PROJECTION);
627 if (projection_3d == DISP_3D_PERSPECTIVE)
628 gluPerspective(60.0,1.0,0.1,100.0);
630 glOrtho(-1.0,1.0,-1.0,1.0,0.1,100.0);;
631 glMatrixMode(GL_MODELVIEW);
634 if (display_mode == DISP_WIREFRAME)
636 glDisable(GL_DEPTH_TEST);
637 glShadeModel(GL_FLAT);
638 glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);
639 glDisable(GL_LIGHTING);
640 glDisable(GL_LIGHT0);
643 else if (display_mode == DISP_SURFACE)
645 glEnable(GL_DEPTH_TEST);
646 glDepthFunc(GL_LESS);
647 glShadeModel(GL_SMOOTH);
648 glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
649 glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,GL_TRUE);
650 glEnable(GL_LIGHTING);
652 glLightfv(GL_LIGHT0,GL_AMBIENT,light_ambient);
653 glLightfv(GL_LIGHT0,GL_DIFFUSE,light_diffuse);
654 glLightfv(GL_LIGHT0,GL_SPECULAR,light_specular);
655 glLightfv(GL_LIGHT0,GL_POSITION,light_position);
656 glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,mat_specular);
657 glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,50.0);
658 glDepthMask(GL_TRUE);
661 else if (display_mode == DISP_TRANSPARENT)
663 glDisable(GL_DEPTH_TEST);
664 glShadeModel(GL_SMOOTH);
665 glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
666 glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,GL_TRUE);
667 glEnable(GL_LIGHTING);
669 glLightfv(GL_LIGHT0,GL_AMBIENT,light_ambient);
670 glLightfv(GL_LIGHT0,GL_DIFFUSE,light_diffuse);
671 glLightfv(GL_LIGHT0,GL_SPECULAR,light_specular);
672 glLightfv(GL_LIGHT0,GL_POSITION,light_position);
673 glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,mat_specular);
674 glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,50.0);
675 glDepthMask(GL_FALSE);
677 glBlendFunc(GL_SRC_ALPHA,GL_ONE);
681 glDisable(GL_DEPTH_TEST);
682 glShadeModel(GL_FLAT);
683 glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);
684 glDisable(GL_LIGHTING);
685 glDisable(GL_LIGHT0);
691 /* Redisplay the hypertorus. */
692 static void display_hypertorus(ModeInfo *mi)
694 hypertorusstruct *hp = &hyper[MI_SCREEN(mi)];
696 if (!hp->button_pressed)
698 hp->alpha += speed_wx * hp->speed_scale;
699 if (hp->alpha >= 360.0)
701 hp->beta += speed_wy * hp->speed_scale;
702 if (hp->beta >= 360.0)
704 hp->delta += speed_wz * hp->speed_scale;
705 if (hp->delta >= 360.0)
707 hp->zeta += speed_xy * hp->speed_scale;
708 if (hp->zeta >= 360.0)
710 hp->eta += speed_xz * hp->speed_scale;
711 if (hp->eta >= 360.0)
713 hp->theta += speed_yz * hp->speed_scale;
714 if (hp->theta >= 360.0)
718 glMatrixMode(GL_PROJECTION);
720 if (projection_3d == DISP_3D_ORTHOGRAPHIC)
722 if (hp->aspect >= 1.0)
723 glOrtho(-hp->aspect,hp->aspect,-1.0,1.0,0.1,100.0);
725 glOrtho(-1.0,1.0,-1.0/hp->aspect,1.0/hp->aspect,0.1,100.0);
729 gluPerspective(60.0,hp->aspect,0.1,100.0);
731 glMatrixMode(GL_MODELVIEW);
734 mi->polygon_count = hypertorus(mi,0.0,2.0*M_PI,0.0,2.0*M_PI,64,64);
738 ENTRYPOINT void reshape_hypertorus(ModeInfo *mi, int width, int height)
740 hypertorusstruct *hp = &hyper[MI_SCREEN(mi)];
742 hp->WindW = (GLint)width;
743 hp->WindH = (GLint)height;
744 glViewport(0,0,width,height);
745 hp->aspect = (GLfloat)width/(GLfloat)height;
749 ENTRYPOINT Bool hypertorus_handle_event(ModeInfo *mi, XEvent *event)
751 hypertorusstruct *hp = &hyper[MI_SCREEN(mi)];
755 if (event->xany.type == KeyPress || event->xany.type == KeyRelease)
756 XLookupString (&event->xkey, &c, 1, &sym, 0);
758 if (event->xany.type == ButtonPress &&
759 event->xbutton.button == Button1)
761 hp->button_pressed = True;
762 gltrackball_start(hp->trackballs[hp->current_trackball],
763 event->xbutton.x, event->xbutton.y,
764 MI_WIDTH(mi), MI_HEIGHT(mi));
767 else if (event->xany.type == ButtonRelease &&
768 event->xbutton.button == Button1)
770 hp->button_pressed = False;
773 else if (event->xany.type == KeyPress)
775 if (sym == XK_Shift_L || sym == XK_Shift_R)
777 hp->current_trackball = 1;
778 if (hp->button_pressed)
779 gltrackball_start(hp->trackballs[hp->current_trackball],
780 event->xbutton.x, event->xbutton.y,
781 MI_WIDTH(mi), MI_HEIGHT(mi));
785 else if (event->xany.type == KeyRelease)
787 if (sym == XK_Shift_L || sym == XK_Shift_R)
789 hp->current_trackball = 0;
790 if (hp->button_pressed)
791 gltrackball_start(hp->trackballs[hp->current_trackball],
792 event->xbutton.x, event->xbutton.y,
793 MI_WIDTH(mi), MI_HEIGHT(mi));
797 else if (event->xany.type == MotionNotify && hp->button_pressed)
799 gltrackball_track(hp->trackballs[hp->current_trackball],
800 event->xmotion.x, event->xmotion.y,
801 MI_WIDTH(mi), MI_HEIGHT(mi));
810 *-----------------------------------------------------------------------------
811 *-----------------------------------------------------------------------------
813 *-----------------------------------------------------------------------------
814 *-----------------------------------------------------------------------------
818 *-----------------------------------------------------------------------------
819 * Initialize hypertorus. Called each time the window changes.
820 *-----------------------------------------------------------------------------
823 ENTRYPOINT void init_hypertorus(ModeInfo *mi)
825 hypertorusstruct *hp;
829 hyper = (hypertorusstruct *)calloc(MI_NUM_SCREENS(mi),
830 sizeof(hypertorusstruct));
834 hp = &hyper[MI_SCREEN(mi)];
837 hp->trackballs[0] = gltrackball_init();
838 hp->trackballs[1] = gltrackball_init();
839 hp->current_trackball = 0;
840 hp->button_pressed = False;
842 /* Set the display mode. */
843 if (!strcasecmp(mode,"wireframe") || !strcasecmp(mode,"0"))
845 display_mode = DISP_WIREFRAME;
847 else if (!strcasecmp(mode,"surface") || !strcasecmp(mode,"1"))
849 display_mode = DISP_SURFACE;
851 else if (!strcasecmp(mode,"transparent") || !strcasecmp(mode,"2"))
853 display_mode = DISP_TRANSPARENT;
857 display_mode = DISP_SURFACE;
860 /* Set the appearance. */
861 if (!strcasecmp(appear,"solid") || !strcasecmp(appear,"0"))
863 appearance = APPEARANCE_SOLID;
865 else if (!strcasecmp(appear,"bands") || !strcasecmp(appear,"1"))
867 appearance = APPEARANCE_BANDS;
870 else if (!strcasecmp(appear,"spirals-1") || !strcasecmp(appear,"3"))
872 appearance = APPEARANCE_SPIRALS;
875 else if (!strcasecmp(appear,"spirals-2") || !strcasecmp(appear,"4"))
877 appearance = APPEARANCE_SPIRALS;
880 else if (!strcasecmp(appear,"spirals-4") || !strcasecmp(appear,"5"))
882 appearance = APPEARANCE_SPIRALS;
885 else if (!strcasecmp(appear,"spirals-8") || !strcasecmp(appear,"6"))
887 appearance = APPEARANCE_SPIRALS;
890 else if (!strcasecmp(appear,"spirals-16") || !strcasecmp(appear,"7"))
892 appearance = APPEARANCE_SPIRALS;
897 appearance = APPEARANCE_BANDS;
901 /* Set the color mode. */
902 if (!strcasecmp(color_mode,"twosided"))
904 colors = COLORS_TWOSIDED;
906 else if (!strcasecmp(color_mode,"colorwheel"))
908 colors = COLORS_COLORWHEEL;
912 colors = COLORS_COLORWHEEL;
915 /* Set the 3d projection mode. */
916 if (!strcasecmp(proj_3d,"perspective") || !strcasecmp(proj_3d,"0"))
918 projection_3d = DISP_3D_PERSPECTIVE;
920 else if (!strcasecmp(proj_3d,"orthographic") || !strcasecmp(proj_3d,"1"))
922 projection_3d = DISP_3D_ORTHOGRAPHIC;
926 projection_3d = DISP_3D_PERSPECTIVE;
929 /* Set the 4d projection mode. */
930 if (!strcasecmp(proj_4d,"perspective") || !strcasecmp(proj_4d,"0"))
932 projection_4d = DISP_4D_PERSPECTIVE;
934 else if (!strcasecmp(proj_4d,"orthographic") || !strcasecmp(proj_4d,"1"))
936 projection_4d = DISP_4D_ORTHOGRAPHIC;
940 projection_4d = DISP_4D_PERSPECTIVE;
943 /* make multiple screens rotate at slightly different rates. */
944 hp->speed_scale = 0.9 + frand(0.3);
946 if ((hp->glx_context = init_GL(mi)) != NULL)
948 reshape_hypertorus(mi,MI_WIDTH(mi),MI_HEIGHT(mi));
949 glDrawBuffer(GL_BACK);
959 *-----------------------------------------------------------------------------
960 * Called by the mainline code periodically to update the display.
961 *-----------------------------------------------------------------------------
963 ENTRYPOINT void draw_hypertorus(ModeInfo *mi)
965 Display *display = MI_DISPLAY(mi);
966 Window window = MI_WINDOW(mi);
967 hypertorusstruct *hp;
971 hp = &hyper[MI_SCREEN(mi)];
973 MI_IS_DRAWN(mi) = True;
974 if (!hp->glx_context)
977 glXMakeCurrent(display,window,*(hp->glx_context));
979 glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
982 display_hypertorus(mi);
989 glXSwapBuffers(display,window);
994 *-----------------------------------------------------------------------------
995 * The display is being taken away from us. Free up malloc'ed
996 * memory and X resources that we've alloc'ed. Only called
997 * once, we must zap everything for every screen.
998 *-----------------------------------------------------------------------------
1001 ENTRYPOINT void release_hypertorus(ModeInfo *mi)
1007 for (screen = 0; screen < MI_NUM_SCREENS(mi); screen++)
1009 hypertorusstruct *hp = &hyper[screen];
1011 if (hp->glx_context)
1012 hp->glx_context = (GLXContext *)NULL;
1014 (void) free((void *)hyper);
1015 hyper = (hypertorusstruct *)NULL;
1021 ENTRYPOINT void change_hypertorus(ModeInfo *mi)
1023 hypertorusstruct *hp = &hyper[MI_SCREEN(mi)];
1025 if (!hp->glx_context)
1028 glXMakeCurrent(MI_DISPLAY(mi),MI_WINDOW(mi),*(hp->glx_context));
1031 #endif /* !STANDALONE */
1033 XSCREENSAVER_MODULE ("Hypertorus", hypertorus)