/* romanboy --- Shows a 3d immersion of the real projective plane that rotates in 3d or on which you can walk and that can deform smoothly between the Roman surface and the Boy surface. */ #if 0 static const char sccsid[] = "@(#)romanboy.c 1.1 14/10/03 xlockmore"; #endif /* Copyright (c) 2013-2014 Carsten Steger . */ /* * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose and without fee is hereby granted, * provided that the above copyright notice appear in all copies and that * both that copyright notice and this permission notice appear in * supporting documentation. * * This file is provided AS IS with no warranties of any kind. The author * shall have no liability with respect to the infringement of copyrights, * trade secrets or any patents by this file or any part thereof. In no * event will the author be liable for any lost revenue or profits or * other special, indirect and consequential damages. * * REVISION HISTORY: * C. Steger - 14/10/03: Initial version */ /* * This program shows a 3d immersion of the real projective plane * that smoothly deforms between the Roman surface and the Boy * surface. You can walk on the projective plane or turn in 3d. The * smooth deformation (homotopy) between these two famous immersions * of the real projective plane was constructed by François Apéry. * * The real projective plane is a non-orientable surface. To make * this apparent, the two-sided color mode can be used. * Alternatively, orientation markers (curling arrows) can be drawn as * a texture map on the surface of the projective plane. While * walking on the projective plane, you will notice that the * orientation of the curling arrows changes (which it must because * the projective plane is non-orientable). * * The real projective plane is a model for the projective geometry in * 2d space. One point can be singled out as the origin. A line can * be singled out as the line at infinity, i.e., a line that lies at * an infinite distance to the origin. The line at infinity is * topologically a circle. Points on the line at infinity are also * used to model directions in projective geometry. The origin can be * visualized in different manners. When using distance colors, the * origin is the point that is displayed as fully saturated red, which * is easier to see as the center of the reddish area on the * projective plane. Alternatively, when using distance bands, the * origin is the center of the only band that projects to a disk. * When using direction bands, the origin is the point where all * direction bands collapse to a point. Finally, when orientation * markers are being displayed, the origin the the point where all * orientation markers are compressed to a point. The line at * infinity can also be visualized in different ways. When using * distance colors, the line at infinity is the line that is displayed * as fully saturated magenta. When two-sided colors are used, the * line at infinity lies at the points where the red and green "sides" * of the projective plane meet (of course, the real projective plane * only has one side, so this is a design choice of the * visualization). Alternatively, when orientation markers are being * displayed, the line at infinity is the place where the orientation * markers change their orientation. * * Note that when the projective plane is displayed with bands, the * orientation markers are placed in the middle of the bands. For * distance bands, the bands are chosen in such a way that the band at * the origin is only half as wide as the remaining bands, which * results in a disk being displayed at the origin that has the same * diameter as the remaining bands. This choice, however, also * implies that the band at infinity is half as wide as the other * bands. Since the projective plane is attached to itself (in a * complicated fashion) at the line at infinity, effectively the band * at infinity is again as wide as the remaining bands. However, * since the orientation markers are displayed in the middle of the * bands, this means that only one half of the orientation markers * will be displayed twice at the line at infinity if distance bands * are used. If direction bands are used or if the projective plane * is displayed as a solid surface, the orientation markers are * displayed fully at the respective sides of the line at infinity. * * The immersed projective plane can be projected to the screen either * perspectively or orthographically. When using the walking modes, * perspective projection to the screen will be used. * * There are three display modes for the projective plane: mesh * (wireframe), solid, or transparent. Furthermore, the appearance of * the projective plane can be as a solid object or as a set of * see-through bands. The bands can be distance bands, i.e., bands * that lie at increasing distances from the origin, or direction * bands, i.e., bands that lie at increasing angles with respect to * the origin. * * When the projective plane is displayed with direction bands, you * will be able to see that each direction band (modulo the "pinching" * at the origin) is a Moebius strip, which also shows that the * projective plane is non-orientable. * * Finally, the colors with with the projective plane is drawn can be * set to two-sided, distance, or direction. In two-sided mode, the * projective plane is drawn with red on one "side" and green on the * "other side". As described above, the projective plane only has * one side, so the color jumps from red to green along the line at * infinity. This mode enables you to see that the projective plane * is non-orientable. In distance mode, the projective plane is * displayed with fully saturated colors that depend on the distance * of the points on the projective plane to the origin. The origin is * displayed in red, the line at infinity is displayed in magenta. If * the projective plane is displayed as distance bands, each band will * be displayed with a different color. In direction mode, the * projective plane is displayed with fully saturated colors that * depend on the angle of the points on the projective plane with * respect to the origin. Angles in opposite directions to the origin * (e.g., 15 and 205 degrees) are displayed in the same color since * they are projectively equivalent. If the projective plane is * displayed as direction bands, each band will be displayed with a * different color. * * The rotation speed for each of the three coordinate axes around * which the projective plane rotates can be chosen. * * Furthermore, in the walking mode the walking direction in the 2d * base square of the projective plane and the walking speed can be * chosen. The walking direction is measured as an angle in degrees * in the 2d square that forms the coordinate system of the surface of * the projective plane. A value of 0 or 180 means that the walk is * along a circle at a randomly chosen distance from the origin * (parallel to a distance band). A value of 90 or 270 means that the * walk is directly from the origin to the line at infinity and back * (analogous to a direction band). Any other value results in a * curved path from the origin to the line at infinity and back. * * By default, the immersion of the real projective plane smoothly * deforms between the Roman and Boy surfaces. It is possible to * choose the speed of the deformation. Furthermore, it is possible * to switch the deformation off. It is also possible to determine * the initial deformation of the immersion. This is mostly useful if * the deformation is switched off, in which case it will determine * the appearance of the surface. * * As a final option, it is possible to display generalized versions * of the immersion discussed above by specifying the order of the * surface. The default surface order of 3 results in the immersion * of the real projective described above. The surface order can be * chosen between 2 and 9. Odd surface orders result in generalized * immersions of the real projective plane, while even numbers result * in a immersion of a topological sphere (which is orientable). The * most interesting even case is a surface order of 2, which results * in an immersion of the halfway model of Morin's sphere eversion (if * the deformation is switched off). * * This program is inspired by François Apéry's book "Models of the * Real Projective Plane", Vieweg, 1987. */ #include "curlicue.h" #ifndef M_PI #define M_PI 3.14159265358979323846 #endif #define DISP_WIREFRAME 0 #define DISP_SURFACE 1 #define DISP_TRANSPARENT 2 #define NUM_DISPLAY_MODES 3 #define APPEARANCE_SOLID 0 #define APPEARANCE_DISTANCE_BANDS 1 #define APPEARANCE_DIRECTION_BANDS 2 #define NUM_APPEARANCES 3 #define COLORS_TWOSIDED 0 #define COLORS_DISTANCE 1 #define COLORS_DIRECTION 2 #define NUM_COLORS 3 #define VIEW_WALK 0 #define VIEW_TURN 1 #define NUM_VIEW_MODES 2 #define DISP_PERSPECTIVE 0 #define DISP_ORTHOGRAPHIC 1 #define NUM_DISP_MODES 2 #define DEF_DISPLAY_MODE "random" #define DEF_APPEARANCE "random" #define DEF_COLORS "random" #define DEF_VIEW_MODE "random" #define DEF_MARKS "False" #define DEF_DEFORM "True" #define DEF_PROJECTION "random" #define DEF_SPEEDX "1.1" #define DEF_SPEEDY "1.3" #define DEF_SPEEDZ "1.5" #define DEF_WALK_DIRECTION "83.0" #define DEF_WALK_SPEED "20.0" #define DEF_DEFORM_SPEED "10.0" #define DEF_INIT_DEFORM "1000.0" #define DEF_SURFACE_ORDER "3" #ifdef STANDALONE # define DEFAULTS "*delay: 10000 \n" \ "*showFPS: False \n" \ # define release_romanboy 0 # include "xlockmore.h" /* from the xscreensaver distribution */ #else /* !STANDALONE */ # include "xlock.h" /* from the xlockmore distribution */ #endif /* !STANDALONE */ #ifdef USE_GL #ifndef HAVE_JWXYZ # include #endif #include "gltrackball.h" #include #ifdef USE_MODULES ModStruct romanboy_description = {"romanboy", "init_romanboy", "draw_romanboy", NULL, "draw_romanboy", "change_romanboy", "free_romanboy", &romanboy_opts, 25000, 1, 1, 1, 1.0, 4, "", "Rotate a 3d immersion of the real projective plane in 3d or walk on it", 0, NULL}; #endif static char *mode; static char *appear; static char *color_mode; static char *view_mode; static Bool marks; static Bool deform; static char *proj; static float speed_x; static float speed_y; static float speed_z; static float walk_direction; static float walk_speed; static float deform_speed; static float init_deform; static int surface_order; static XrmOptionDescRec opts[] = { {"-mode", ".displayMode", XrmoptionSepArg, 0 }, {"-wireframe", ".displayMode", XrmoptionNoArg, "wireframe" }, {"-surface", ".displayMode", XrmoptionNoArg, "surface" }, {"-transparent", ".displayMode", XrmoptionNoArg, "transparent" }, {"-appearance", ".appearance", XrmoptionSepArg, 0 }, {"-solid", ".appearance", XrmoptionNoArg, "solid" }, {"-distance-bands", ".appearance", XrmoptionNoArg, "distance-bands" }, {"-direction-bands", ".appearance", XrmoptionNoArg, "direction-bands" }, {"-colors", ".colors", XrmoptionSepArg, 0 }, {"-twosided-colors", ".colors", XrmoptionNoArg, "two-sided" }, {"-distance-colors", ".colors", XrmoptionNoArg, "distance" }, {"-direction-colors", ".colors", XrmoptionNoArg, "direction" }, {"-view-mode", ".viewMode", XrmoptionSepArg, 0 }, {"-walk", ".viewMode", XrmoptionNoArg, "walk" }, {"-turn", ".viewMode", XrmoptionNoArg, "turn" }, {"-deform", ".deform", XrmoptionNoArg, "on"}, {"+deform", ".deform", XrmoptionNoArg, "off"}, {"-orientation-marks", ".marks", XrmoptionNoArg, "on"}, {"+orientation-marks", ".marks", XrmoptionNoArg, "off"}, {"-projection", ".projection", XrmoptionSepArg, 0 }, {"-perspective", ".projection", XrmoptionNoArg, "perspective" }, {"-orthographic", ".projection", XrmoptionNoArg, "orthographic" }, {"-speed-x", ".speedx", XrmoptionSepArg, 0 }, {"-speed-y", ".speedy", XrmoptionSepArg, 0 }, {"-speed-z", ".speedz", XrmoptionSepArg, 0 }, {"-walk-direction", ".walkDirection", XrmoptionSepArg, 0 }, {"-walk-speed", ".walkSpeed", XrmoptionSepArg, 0 }, {"-deformation-speed", ".deformSpeed", XrmoptionSepArg, 0 }, {"-initial-deformation", ".initDeform", XrmoptionSepArg, 0 }, {"-roman", ".initDeform", XrmoptionNoArg, "0.0" }, {"-boy", ".initDeform", XrmoptionNoArg, "1000.0" }, {"-surface-order", ".surfaceOrder", XrmoptionSepArg, 0 }, }; static argtype vars[] = { { &mode, "displayMode", "DisplayMode", DEF_DISPLAY_MODE, t_String }, { &appear, "appearance", "Appearance", DEF_APPEARANCE, t_String }, { &color_mode, "colors", "Colors", DEF_COLORS, t_String }, { &view_mode, "viewMode", "ViewMode", DEF_VIEW_MODE, t_String }, { &deform, "deform", "Deform", DEF_DEFORM, t_Bool }, { &marks, "marks", "Marks", DEF_MARKS, t_Bool }, { &proj, "projection", "Projection", DEF_PROJECTION, t_String }, { &speed_x, "speedx", "Speedx", DEF_SPEEDX, t_Float}, { &speed_y, "speedy", "Speedy", DEF_SPEEDY, t_Float}, { &speed_z, "speedz", "Speedz", DEF_SPEEDZ, t_Float}, { &walk_direction, "walkDirection", "WalkDirection", DEF_WALK_DIRECTION, t_Float}, { &walk_speed, "walkSpeed", "WalkSpeed", DEF_WALK_SPEED, t_Float}, { &deform_speed, "deformSpeed", "DeformSpeed", DEF_DEFORM_SPEED, t_Float}, { &init_deform, "initDeform", "InitDeform", DEF_INIT_DEFORM, t_Float }, { &surface_order, "surfaceOrder", "SurfaceOrder", DEF_SURFACE_ORDER, t_Int } }; ENTRYPOINT ModeSpecOpt romanboy_opts = {sizeof opts / sizeof opts[0], opts, sizeof vars / sizeof vars[0], vars, NULL}; /* Offset by which we walk above the projective plane */ #define DELTAY 0.01 /* Number of subdivisions of the projective plane */ #define NUMU 64 #define NUMV 128 /* Number of subdivisions per band */ #define NUMB 8 typedef struct { GLint WindH, WindW; GLXContext *glx_context; /* Options */ int display_mode; int appearance; int colors; int view; int projection; Bool marks; /* 3D rotation angles */ float alpha, beta, delta; /* Movement parameters */ float umove, vmove, dumove, dvmove; int side, dir; /* Deformation parameters */ float dd; int defdir; /* The type of the generalized Roman-Boy surface */ int g; /* The viewing offset in 3d */ float offset3d[3]; /* The 3d coordinates of the projective plane and their derivatives */ float *pp; float *pn; /* The precomputed colors of the projective plane */ float *col; /* The precomputed texture coordinates of the projective plane */ float *tex; /* The "curlicue" texture */ GLuint tex_name; /* Aspect ratio of the current window */ float aspect; /* Trackball states */ trackball_state *trackball; Bool button_pressed; /* A random factor to modify the rotation speeds */ float speed_scale; } romanboystruct; static romanboystruct *romanboy = (romanboystruct *) NULL; /* Add a rotation around the x-axis to the matrix m. */ static void rotatex(float m[3][3], float phi) { float c, s, u, v; int i; phi *= M_PI/180.0; c = cos(phi); s = sin(phi); for (i=0; i<3; i++) { u = m[i][1]; v = m[i][2]; m[i][1] = c*u+s*v; m[i][2] = -s*u+c*v; } } /* Add a rotation around the y-axis to the matrix m. */ static void rotatey(float m[3][3], float phi) { float c, s, u, v; int i; phi *= M_PI/180.0; c = cos(phi); s = sin(phi); for (i=0; i<3; i++) { u = m[i][0]; v = m[i][2]; m[i][0] = c*u-s*v; m[i][2] = s*u+c*v; } } /* Add a rotation around the z-axis to the matrix m. */ static void rotatez(float m[3][3], float phi) { float c, s, u, v; int i; phi *= M_PI/180.0; c = cos(phi); s = sin(phi); for (i=0; i<3; i++) { u = m[i][0]; v = m[i][1]; m[i][0] = c*u+s*v; m[i][1] = -s*u+c*v; } } /* Compute the rotation matrix m from the rotation angles. */ static void rotateall(float al, float be, float de, float m[3][3]) { int i, j; for (i=0; i<3; i++) for (j=0; j<3; j++) m[i][j] = (i==j); rotatex(m,al); rotatey(m,be); rotatez(m,de); } /* Multiply two rotation matrices: o=m*n. */ static void mult_rotmat(float m[3][3], float n[3][3], float o[3][3]) { int i, j, k; for (i=0; i<3; i++) { for (j=0; j<3; j++) { o[i][j] = 0.0; for (k=0; k<3; k++) o[i][j] += m[i][k]*n[k][j]; } } } /* Compute a 3D rotation matrix from a unit quaternion. */ static void quat_to_rotmat(float p[4], float m[3][3]) { double al, be, de; double r00, r01, r02, r12, r22; r00 = 1.0-2.0*(p[1]*p[1]+p[2]*p[2]); r01 = 2.0*(p[0]*p[1]+p[2]*p[3]); r02 = 2.0*(p[2]*p[0]-p[1]*p[3]); r12 = 2.0*(p[1]*p[2]+p[0]*p[3]); r22 = 1.0-2.0*(p[1]*p[1]+p[0]*p[0]); al = atan2(-r12,r22)*180.0/M_PI; be = atan2(r02,sqrt(r00*r00+r01*r01))*180.0/M_PI; de = atan2(-r01,r00)*180.0/M_PI; rotateall(al,be,de,m); } /* Compute a fully saturated and bright color based on an angle. */ static void color(romanboystruct *pp, double angle, float col[4]) { int s; double t; if (pp->colors == COLORS_TWOSIDED) return; if (angle >= 0.0) angle = fmod(angle,2.0*M_PI); else angle = fmod(angle,-2.0*M_PI); s = floor(angle/(M_PI/3)); t = angle/(M_PI/3)-s; if (s >= 6) s = 0; switch (s) { case 0: col[0] = 1.0; col[1] = t; col[2] = 0.0; break; case 1: col[0] = 1.0-t; col[1] = 1.0; col[2] = 0.0; break; case 2: col[0] = 0.0; col[1] = 1.0; col[2] = t; break; case 3: col[0] = 0.0; col[1] = 1.0-t; col[2] = 1.0; break; case 4: col[0] = t; col[1] = 0.0; col[2] = 1.0; break; case 5: col[0] = 1.0; col[1] = 0.0; col[2] = 1.0-t; break; } if (pp->display_mode == DISP_TRANSPARENT) col[3] = 0.7; else col[3] = 1.0; } /* Set up the projective plane colors and texture. */ static void setup_roman_boy_color_texture(ModeInfo *mi, double umin, double umax, double vmin, double vmax, int numu, int numv) { int i, j, k, g; double u, v, ur, vr; romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; g = pp->g; ur = umax-umin; vr = vmax-vmin; for (i=0; i<=numv; i++) { for (j=0; j<=numu; j++) { k = i*(numu+1)+j; if (pp->appearance != APPEARANCE_DIRECTION_BANDS) u = -ur*j/numu+umin; else u = ur*j/numu+umin; v = vr*i/numv+vmin; if (pp->colors == COLORS_DIRECTION) color(pp,2.0*M_PI-fmod(2.0*u,2.0*M_PI),&pp->col[4*k]); else /* pp->colors == COLORS_DISTANCE */ color(pp,v*(5.0/6.0),&pp->col[4*k]); pp->tex[2*k+0] = -16*g*u/(2.0*M_PI); if (pp->appearance == APPEARANCE_DISTANCE_BANDS) pp->tex[2*k+1] = 32*v/(2.0*M_PI)-0.5; else pp->tex[2*k+1] = 32*v/(2.0*M_PI); } } } /* Draw a 3d immersion of the projective plane. */ static int roman_boy(ModeInfo *mi, double umin, double umax, double vmin, double vmax, int numu, int numv) { int polys = 0; static const GLfloat mat_diff_red[] = { 1.0, 0.0, 0.0, 1.0 }; static const GLfloat mat_diff_green[] = { 0.0, 1.0, 0.0, 1.0 }; static const GLfloat mat_diff_trans_red[] = { 1.0, 0.0, 0.0, 0.7 }; static const GLfloat mat_diff_trans_green[] = { 0.0, 1.0, 0.0, 0.7 }; float p[3], pu[3], pv[3], pm[3], n[3], b[3], mat[3][3]; int i, j, k, l, m, o, g; double u, v, ur, vr, oz; double xx[3], xxu[3], xxv[3]; double r, s, t; double d, dd, radius; double cu, su, cgu, sgu, cgm1u, sgm1u, cv, c2v, s2v, cv2; double sqrt2og, h1m1og, gm1, nomx, nomy, nomux, nomuy, nomvx, nomvy; double den, den2, denu, denv; float qu[4], r1[3][3], r2[3][3]; romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; g = pp->g; dd = pp->dd; d = ((6.0*dd-15.0)*dd+10.0)*dd*dd*dd; r = 1.0+d*d*(1.0/2.0+d*d*(1.0/6.0+d*d*(1.0/3.0))); radius = 1.0/r; oz = 0.5*r; if (pp->view == VIEW_WALK) { u = pp->umove; v = pp->vmove; if (g & 1) v = 0.5*M_PI-0.25*v; else v = 0.5*M_PI-0.5*v; sqrt2og = M_SQRT2/g; h1m1og = 0.5*(1.0-1.0/g); gm1 = g-1.0; cu = cos(u); su = sin(u); cgu = cos(g*u); sgu = sin(g*u); cgm1u = cos(gm1*u); sgm1u = sin(gm1*u); cv = cos(v); c2v = cos(2.0*v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; nomux = -sqrt2og*cv2*gm1*sgm1u-h1m1og*s2v*su; nomuy = sqrt2og*cv2*gm1*cgm1u-h1m1og*s2v*cu; nomvx = -sqrt2og*s2v*cgm1u+2.0*h1m1og*c2v*cu; nomvy = -sqrt2og*s2v*sgm1u-2.0*h1m1og*c2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); den2 = den*den; denu = 0.5*M_SQRT2*d*g*cgu*s2v; denv = M_SQRT2*d*sgu*c2v; xx[0] = nomx*den; xx[1] = nomy*den; xx[2] = cv2*den-oz; /* Avoid degenerate tangential plane basis vectors. */ if (0.5*M_PI-fabs(v) < FLT_EPSILON) { if (0.5*M_PI-v < FLT_EPSILON) v = 0.5*M_PI-FLT_EPSILON; else v = -0.5*M_PI+FLT_EPSILON; cv = cos(v); c2v = cos(2.0*v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; nomux = -sqrt2og*cv2*gm1*sgm1u-h1m1og*s2v*su; nomuy = sqrt2og*cv2*gm1*cgm1u-h1m1og*s2v*cu; nomvx = -sqrt2og*s2v*cgm1u+2.0*h1m1og*c2v*cu; nomvy = -sqrt2og*s2v*sgm1u-2.0*h1m1og*c2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); den2 = den*den; denu = 0.5*M_SQRT2*d*g*cgu*s2v; denv = M_SQRT2*d*sgu*c2v; } xxu[0] = nomux*den+nomx*denu*den2; xxu[1] = nomuy*den+nomy*denu*den2; xxu[2] = cv2*denu*den2; xxv[0] = nomvx*den+nomx*denv*den2; xxv[1] = nomvy*den+nomy*denv*den2; xxv[2] = -s2v*den+cv2*denv*den2; for (l=0; l<3; l++) { p[l] = xx[l]*radius; pu[l] = xxu[l]*radius; pv[l] = xxv[l]*radius; } n[0] = pu[1]*pv[2]-pu[2]*pv[1]; n[1] = pu[2]*pv[0]-pu[0]*pv[2]; n[2] = pu[0]*pv[1]-pu[1]*pv[0]; t = 1.0/(pp->side*4.0*sqrt(n[0]*n[0]+n[1]*n[1]+n[2]*n[2])); n[0] *= t; n[1] *= t; n[2] *= t; pm[0] = pu[0]*pp->dumove-pv[0]*0.25*pp->dvmove; pm[1] = pu[1]*pp->dumove-pv[1]*0.25*pp->dvmove; pm[2] = pu[2]*pp->dumove-pv[2]*0.25*pp->dvmove; t = 1.0/(4.0*sqrt(pm[0]*pm[0]+pm[1]*pm[1]+pm[2]*pm[2])); pm[0] *= t; pm[1] *= t; pm[2] *= t; b[0] = n[1]*pm[2]-n[2]*pm[1]; b[1] = n[2]*pm[0]-n[0]*pm[2]; b[2] = n[0]*pm[1]-n[1]*pm[0]; t = 1.0/(4.0*sqrt(b[0]*b[0]+b[1]*b[1]+b[2]*b[2])); b[0] *= t; b[1] *= t; b[2] *= t; /* Compute alpha, beta, gamma from the three basis vectors. | -b[0] -b[1] -b[2] | m = | n[0] n[1] n[2] | | -pm[0] -pm[1] -pm[2] | */ pp->alpha = atan2(-n[2],-pm[2])*180/M_PI; pp->beta = atan2(-b[2],sqrt(b[0]*b[0]+b[1]*b[1]))*180/M_PI; pp->delta = atan2(b[1],-b[0])*180/M_PI; /* Compute the rotation that rotates the projective plane in 3D. */ rotateall(pp->alpha,pp->beta,pp->delta,mat); u = pp->umove; v = pp->vmove; if (g & 1) v = 0.5*M_PI-0.25*v; else v = 0.5*M_PI-0.5*v; sqrt2og = M_SQRT2/g; h1m1og = 0.5*(1.0-1.0/g); gm1 = g-1.0; cu = cos(u); su = sin(u); sgu = sin(g*u); cgm1u = cos(gm1*u); sgm1u = sin(gm1*u); cv = cos(v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); xx[0] = nomx*den; xx[1] = nomy*den; xx[2] = cv2*den-oz; for (l=0; l<3; l++) { r = 0.0; for (m=0; m<3; m++) r += mat[l][m]*xx[m]; p[l] = r*radius; } pp->offset3d[0] = -p[0]; pp->offset3d[1] = -p[1]-DELTAY; pp->offset3d[2] = -p[2]; } else { /* Compute the rotation that rotates the projective plane in 3D, including the trackball rotations. */ rotateall(pp->alpha,pp->beta,pp->delta,r1); gltrackball_get_quaternion(pp->trackball,qu); quat_to_rotmat(qu,r2); mult_rotmat(r2,r1,mat); } if (pp->colors == COLORS_TWOSIDED) { glColor3fv(mat_diff_red); if (pp->display_mode == DISP_TRANSPARENT) { glMaterialfv(GL_FRONT,GL_AMBIENT_AND_DIFFUSE,mat_diff_trans_red); glMaterialfv(GL_BACK,GL_AMBIENT_AND_DIFFUSE,mat_diff_trans_green); } else { glMaterialfv(GL_FRONT,GL_AMBIENT_AND_DIFFUSE,mat_diff_red); glMaterialfv(GL_BACK,GL_AMBIENT_AND_DIFFUSE,mat_diff_green); } } glBindTexture(GL_TEXTURE_2D,pp->tex_name); ur = umax-umin; vr = vmax-vmin; /* Set up the projective plane coordinates and normals. */ if (pp->appearance != APPEARANCE_DIRECTION_BANDS) { for (i=0; i<=numv; i++) { if (pp->appearance == APPEARANCE_DISTANCE_BANDS && ((i & (NUMB-1)) >= NUMB/4+1) && ((i & (NUMB-1)) < 3*NUMB/4)) continue; for (j=0; j<=numu; j++) { o = i*(numu+1)+j; u = ur*j/numu+umin; v = vr*i/numv+vmin; if (g & 1) v = 0.5*M_PI-0.25*v; else v = 0.5*M_PI-0.5*v; sqrt2og = M_SQRT2/g; h1m1og = 0.5*(1.0-1.0/g); gm1 = g-1.0; cu = cos(u); su = sin(u); cgu = cos(g*u); sgu = sin(g*u); cgm1u = cos(gm1*u); sgm1u = sin(gm1*u); cv = cos(v); c2v = cos(2.0*v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; nomux = -sqrt2og*cv2*gm1*sgm1u-h1m1og*s2v*su; nomuy = sqrt2og*cv2*gm1*cgm1u-h1m1og*s2v*cu; nomvx = -sqrt2og*s2v*cgm1u+2.0*h1m1og*c2v*cu; nomvy = -sqrt2og*s2v*sgm1u-2.0*h1m1og*c2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); den2 = den*den; denu = 0.5*M_SQRT2*d*g*cgu*s2v; denv = M_SQRT2*d*sgu*c2v; xx[0] = nomx*den; xx[1] = nomy*den; xx[2] = cv2*den-oz; /* Avoid degenerate tangential plane basis vectors. */ if (0.5*M_PI-fabs(v) < FLT_EPSILON) { if (0.5*M_PI-v < FLT_EPSILON) v = 0.5*M_PI-FLT_EPSILON; else v = -0.5*M_PI+FLT_EPSILON; cv = cos(v); c2v = cos(2.0*v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; nomux = -sqrt2og*cv2*gm1*sgm1u-h1m1og*s2v*su; nomuy = sqrt2og*cv2*gm1*cgm1u-h1m1og*s2v*cu; nomvx = -sqrt2og*s2v*cgm1u+2.0*h1m1og*c2v*cu; nomvy = -sqrt2og*s2v*sgm1u-2.0*h1m1og*c2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); den2 = den*den; denu = 0.5*M_SQRT2*d*g*cgu*s2v; denv = M_SQRT2*d*sgu*c2v; } xxu[0] = nomux*den+nomx*denu*den2; xxu[1] = nomuy*den+nomy*denu*den2; xxu[2] = cv2*denu*den2; xxv[0] = nomvx*den+nomx*denv*den2; xxv[1] = nomvy*den+nomy*denv*den2; xxv[2] = -s2v*den+cv2*denv*den2; for (l=0; l<3; l++) { r = 0.0; s = 0.0; t = 0.0; for (m=0; m<3; m++) { r += mat[l][m]*xx[m]; s += mat[l][m]*xxu[m]; t += mat[l][m]*xxv[m]; } p[l] = r*radius+pp->offset3d[l]; pu[l] = s*radius; pv[l] = t*radius; } n[0] = pu[1]*pv[2]-pu[2]*pv[1]; n[1] = pu[2]*pv[0]-pu[0]*pv[2]; n[2] = pu[0]*pv[1]-pu[1]*pv[0]; t = 1.0/sqrt(n[0]*n[0]+n[1]*n[1]+n[2]*n[2]); n[0] *= t; n[1] *= t; n[2] *= t; pp->pp[3*o+0] = p[0]; pp->pp[3*o+1] = p[1]; pp->pp[3*o+2] = p[2]; pp->pn[3*o+0] = n[0]; pp->pn[3*o+1] = n[1]; pp->pn[3*o+2] = n[2]; } } } else /* pp->appearance == APPEARANCE_DIRECTION_BANDS */ { for (j=0; j<=numu; j++) { if ((j & (NUMB-1)) >= NUMB/2+1) continue; for (i=0; i<=numv; i++) { o = i*(numu+1)+j; u = -ur*j/numu+umin; v = vr*i/numv+vmin; if (g & 1) v = 0.5*M_PI-0.25*v; else v = 0.5*M_PI-0.5*v; sqrt2og = M_SQRT2/g; h1m1og = 0.5*(1.0-1.0/g); gm1 = g-1.0; cu = cos(u); su = sin(u); cgu = cos(g*u); sgu = sin(g*u); cgm1u = cos(gm1*u); sgm1u = sin(gm1*u); cv = cos(v); c2v = cos(2.0*v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; nomux = -sqrt2og*cv2*gm1*sgm1u-h1m1og*s2v*su; nomuy = sqrt2og*cv2*gm1*cgm1u-h1m1og*s2v*cu; nomvx = -sqrt2og*s2v*cgm1u+2.0*h1m1og*c2v*cu; nomvy = -sqrt2og*s2v*sgm1u-2.0*h1m1og*c2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); den2 = den*den; denu = 0.5*M_SQRT2*d*g*cgu*s2v; denv = M_SQRT2*d*sgu*c2v; xx[0] = nomx*den; xx[1] = nomy*den; xx[2] = cv2*den-oz; /* Avoid degenerate tangential plane basis vectors. */ if (0.5*M_PI-fabs(v) < FLT_EPSILON) { if (0.5*M_PI-v < FLT_EPSILON) v = 0.5*M_PI-FLT_EPSILON; else v = -0.5*M_PI+FLT_EPSILON; cv = cos(v); c2v = cos(2.0*v); s2v = sin(2.0*v); cv2 = cv*cv; nomx = sqrt2og*cv2*cgm1u+h1m1og*s2v*cu; nomy = sqrt2og*cv2*sgm1u-h1m1og*s2v*su; nomux = -sqrt2og*cv2*gm1*sgm1u-h1m1og*s2v*su; nomuy = sqrt2og*cv2*gm1*cgm1u-h1m1og*s2v*cu; nomvx = -sqrt2og*s2v*cgm1u+2.0*h1m1og*c2v*cu; nomvy = -sqrt2og*s2v*sgm1u-2.0*h1m1og*c2v*su; den = 1.0/(1.0-0.5*M_SQRT2*d*s2v*sgu); den2 = den*den; denu = 0.5*M_SQRT2*d*g*cgu*s2v; denv = M_SQRT2*d*sgu*c2v; } xxu[0] = nomux*den+nomx*denu*den2; xxu[1] = nomuy*den+nomy*denu*den2; xxu[2] = cv2*denu*den2; xxv[0] = nomvx*den+nomx*denv*den2; xxv[1] = nomvy*den+nomy*denv*den2; xxv[2] = -s2v*den+cv2*denv*den2; for (l=0; l<3; l++) { r = 0.0; s = 0.0; t = 0.0; for (m=0; m<3; m++) { r += mat[l][m]*xx[m]; s += mat[l][m]*xxu[m]; t += mat[l][m]*xxv[m]; } p[l] = r*radius+pp->offset3d[l]; pu[l] = s*radius; pv[l] = t*radius; } n[0] = pu[1]*pv[2]-pu[2]*pv[1]; n[1] = pu[2]*pv[0]-pu[0]*pv[2]; n[2] = pu[0]*pv[1]-pu[1]*pv[0]; t = 1.0/sqrt(n[0]*n[0]+n[1]*n[1]+n[2]*n[2]); n[0] *= t; n[1] *= t; n[2] *= t; pp->pp[3*o+0] = p[0]; pp->pp[3*o+1] = p[1]; pp->pp[3*o+2] = p[2]; pp->pn[3*o+0] = n[0]; pp->pn[3*o+1] = n[1]; pp->pn[3*o+2] = n[2]; } } } if (pp->appearance != APPEARANCE_DIRECTION_BANDS) { for (i=0; iappearance == APPEARANCE_DISTANCE_BANDS && ((i & (NUMB-1)) >= NUMB/4) && ((i & (NUMB-1)) < 3*NUMB/4)) continue; if (pp->display_mode == DISP_WIREFRAME) glBegin(GL_QUAD_STRIP); else glBegin(GL_TRIANGLE_STRIP); for (j=0; j<=numu; j++) { for (k=0; k<=1; k++) { l = (i+k); m = j; o = l*(numu+1)+m; glTexCoord2fv(&pp->tex[2*o]); if (pp->colors != COLORS_TWOSIDED) { glColor3fv(&pp->col[4*o]); glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT_AND_DIFFUSE, &pp->col[4*o]); } glNormal3fv(&pp->pn[3*o]); glVertex3fv(&pp->pp[3*o]); polys++; } } glEnd(); } } else /* pp->appearance == APPEARANCE_DIRECTION_BANDS */ { for (j=0; j= NUMB/2) continue; if (pp->display_mode == DISP_WIREFRAME) glBegin(GL_QUAD_STRIP); else glBegin(GL_TRIANGLE_STRIP); for (i=0; i<=numv; i++) { for (k=0; k<=1; k++) { l = i; m = (j+k); o = l*(numu+1)+m; glTexCoord2fv(&pp->tex[2*o]); if (pp->colors != COLORS_TWOSIDED) { glColor3fv(&pp->col[4*o]); glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT_AND_DIFFUSE, &pp->col[4*o]); } glNormal3fv(&pp->pn[3*o]); glVertex3fv(&pp->pp[3*o]); polys++; } } glEnd(); } } polys /= 2; return polys; } /* Generate a texture image that shows the orientation reversal. */ static void gen_texture(ModeInfo *mi) { romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; glGenTextures(1,&pp->tex_name); glBindTexture(GL_TEXTURE_2D,pp->tex_name); glPixelStorei(GL_UNPACK_ALIGNMENT,1); glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT); glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT); glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR); glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE); glTexImage2D(GL_TEXTURE_2D,0,GL_RGB,TEX_DIMENSION,TEX_DIMENSION,0, GL_LUMINANCE,GL_UNSIGNED_BYTE,texture); } static void init(ModeInfo *mi) { static const GLfloat light_ambient[] = { 0.0, 0.0, 0.0, 1.0 }; static const GLfloat light_diffuse[] = { 1.0, 1.0, 1.0, 1.0 }; static const GLfloat light_specular[] = { 1.0, 1.0, 1.0, 1.0 }; static const GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 }; static const GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 }; romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; if (deform_speed == 0.0) deform_speed = 10.0; if (init_deform < 0.0) init_deform = 0.0; if (init_deform > 1000.0) init_deform = 1000.0; if (walk_speed == 0.0) walk_speed = 20.0; if (pp->view == VIEW_TURN) { pp->alpha = frand(360.0); pp->beta = frand(360.0); pp->delta = frand(360.0); } else { pp->alpha = 0.0; pp->beta = 0.0; pp->delta = 0.0; } pp->umove = frand(2.0*M_PI); pp->vmove = frand(2.0*M_PI); pp->dumove = 0.0; pp->dvmove = 0.0; pp->side = 1; if (sin(walk_direction*M_PI/180.0) >= 0.0) pp->dir = 1; else pp->dir = -1; pp->dd = init_deform*0.001; pp->defdir = -1; pp->offset3d[0] = 0.0; pp->offset3d[1] = 0.0; pp->offset3d[2] = -1.8; gen_texture(mi); setup_roman_boy_color_texture(mi,0.0,2.0*M_PI,0.0,2.0*M_PI,pp->g*NUMU,NUMV); if (pp->marks) glEnable(GL_TEXTURE_2D); else glDisable(GL_TEXTURE_2D); glMatrixMode(GL_PROJECTION); glLoadIdentity(); if (pp->projection == DISP_PERSPECTIVE || pp->view == VIEW_WALK) { if (pp->view == VIEW_WALK) gluPerspective(60.0,1.0,0.01,10.0); else gluPerspective(60.0,1.0,0.1,10.0); } else { glOrtho(-1.0,1.0,-1.0,1.0,0.1,10.0); } glMatrixMode(GL_MODELVIEW); glLoadIdentity(); # ifdef HAVE_JWZGLES /* #### glPolygonMode other than GL_FILL unimplemented */ if (pp->display_mode == DISP_WIREFRAME) pp->display_mode = DISP_SURFACE; # endif if (pp->display_mode == DISP_SURFACE) { glEnable(GL_DEPTH_TEST); glDepthFunc(GL_LESS); glShadeModel(GL_SMOOTH); glPolygonMode(GL_FRONT_AND_BACK,GL_FILL); glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,GL_TRUE); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glLightfv(GL_LIGHT0,GL_AMBIENT,light_ambient); glLightfv(GL_LIGHT0,GL_DIFFUSE,light_diffuse); glLightfv(GL_LIGHT0,GL_SPECULAR,light_specular); glLightfv(GL_LIGHT0,GL_POSITION,light_position); glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,mat_specular); glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,50.0); glDepthMask(GL_TRUE); glDisable(GL_BLEND); } else if (pp->display_mode == DISP_TRANSPARENT) { glDisable(GL_DEPTH_TEST); glShadeModel(GL_SMOOTH); glPolygonMode(GL_FRONT_AND_BACK,GL_FILL); glLightModeli(GL_LIGHT_MODEL_TWO_SIDE,GL_TRUE); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); glLightfv(GL_LIGHT0,GL_AMBIENT,light_ambient); glLightfv(GL_LIGHT0,GL_DIFFUSE,light_diffuse); glLightfv(GL_LIGHT0,GL_SPECULAR,light_specular); glLightfv(GL_LIGHT0,GL_POSITION,light_position); glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,mat_specular); glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,50.0); glDepthMask(GL_FALSE); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA,GL_ONE); } else /* pp->display_mode == DISP_WIREFRAME */ { glDisable(GL_DEPTH_TEST); glShadeModel(GL_FLAT); glPolygonMode(GL_FRONT_AND_BACK,GL_LINE); glDisable(GL_LIGHTING); glDisable(GL_LIGHT0); glDisable(GL_BLEND); } } /* Redisplay the Klein bottle. */ static void display_romanboy(ModeInfo *mi) { romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; if (!pp->button_pressed) { if (deform) { pp->dd += pp->defdir*deform_speed*0.001; if (pp->dd < 0.0) { pp->dd = -pp->dd; pp->defdir = -pp->defdir; } if (pp->dd > 1.0) { pp->dd = 2.0-pp->dd; pp->defdir = -pp->defdir; } } if (pp->view == VIEW_TURN) { pp->alpha += speed_x * pp->speed_scale; if (pp->alpha >= 360.0) pp->alpha -= 360.0; pp->beta += speed_y * pp->speed_scale; if (pp->beta >= 360.0) pp->beta -= 360.0; pp->delta += speed_z * pp->speed_scale; if (pp->delta >= 360.0) pp->delta -= 360.0; } if (pp->view == VIEW_WALK) { pp->dvmove = (pp->dir*sin(walk_direction*M_PI/180.0)* walk_speed*M_PI/4096.0); pp->vmove += pp->dvmove; if (pp->vmove > 2.0*M_PI) { pp->vmove = 4.0*M_PI-pp->vmove; pp->umove = pp->umove-M_PI; if (pp->umove < 0.0) pp->umove += 2.0*M_PI; pp->side = -pp->side; pp->dir = -pp->dir; pp->dvmove = -pp->dvmove; } if (pp->vmove < 0.0) { pp->vmove = -pp->vmove; pp->umove = pp->umove-M_PI; if (pp->umove < 0.0) pp->umove += 2.0*M_PI; pp->dir = -pp->dir; pp->dvmove = -pp->dvmove; } pp->dumove = cos(walk_direction*M_PI/180.0)*walk_speed*M_PI/4096.0; pp->umove += pp->dumove; if (pp->umove >= 2.0*M_PI) pp->umove -= 2.0*M_PI; if (pp->umove < 0.0) pp->umove += 2.0*M_PI; } } glMatrixMode(GL_PROJECTION); glLoadIdentity(); if (pp->projection == DISP_PERSPECTIVE || pp->view == VIEW_WALK) { if (pp->view == VIEW_WALK) gluPerspective(60.0,pp->aspect,0.01,10.0); else gluPerspective(60.0,pp->aspect,0.1,10.0); } else { if (pp->aspect >= 1.0) glOrtho(-pp->aspect,pp->aspect,-1.0,1.0,0.1,10.0); else glOrtho(-1.0,1.0,-1.0/pp->aspect,1.0/pp->aspect,0.1,10.0); } glMatrixMode(GL_MODELVIEW); glLoadIdentity(); mi->polygon_count = roman_boy(mi,0.0,2.0*M_PI,0.0,2.0*M_PI,pp->g*NUMU,NUMV); } ENTRYPOINT void reshape_romanboy(ModeInfo *mi, int width, int height) { romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; int y = 0; if (width > height * 5) { /* tiny window: show middle */ height = width; y = -height/2; } pp->WindW = (GLint)width; pp->WindH = (GLint)height; glViewport(0,y,width,height); pp->aspect = (GLfloat)width/(GLfloat)height; } ENTRYPOINT Bool romanboy_handle_event(ModeInfo *mi, XEvent *event) { romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; if (event->xany.type == ButtonPress && event->xbutton.button == Button1) { pp->button_pressed = True; gltrackball_start(pp->trackball, event->xbutton.x, event->xbutton.y, MI_WIDTH(mi), MI_HEIGHT(mi)); return True; } else if (event->xany.type == ButtonRelease && event->xbutton.button == Button1) { pp->button_pressed = False; return True; } else if (event->xany.type == MotionNotify && pp->button_pressed) { gltrackball_track(pp->trackball, event->xmotion.x, event->xmotion.y, MI_WIDTH(mi), MI_HEIGHT(mi)); return True; } return False; } /* *----------------------------------------------------------------------------- *----------------------------------------------------------------------------- * Xlock hooks. *----------------------------------------------------------------------------- *----------------------------------------------------------------------------- */ /* *----------------------------------------------------------------------------- * Initialize romanboy. Called each time the window changes. *----------------------------------------------------------------------------- */ ENTRYPOINT void init_romanboy(ModeInfo *mi) { romanboystruct *pp; MI_INIT (mi, romanboy); pp = &romanboy[MI_SCREEN(mi)]; if (surface_order < 2) pp->g = 2; else if (surface_order > 9) pp->g = 9; else pp->g = surface_order; pp->pp = calloc(3*pp->g*(NUMU+1)*(NUMV+1),sizeof(float)); pp->pn = calloc(3*pp->g*(NUMU+1)*(NUMV+1),sizeof(float)); pp->col = calloc(4*pp->g*(NUMU+1)*(NUMV+1),sizeof(float)); pp->tex = calloc(2*pp->g*(NUMU+1)*(NUMV+1),sizeof(float)); pp->trackball = gltrackball_init(True); pp->button_pressed = False; /* Set the display mode. */ if (!strcasecmp(mode,"random")) { pp->display_mode = random() % NUM_DISPLAY_MODES; } else if (!strcasecmp(mode,"wireframe")) { pp->display_mode = DISP_WIREFRAME; } else if (!strcasecmp(mode,"surface")) { pp->display_mode = DISP_SURFACE; } else if (!strcasecmp(mode,"transparent")) { pp->display_mode = DISP_TRANSPARENT; } else { pp->display_mode = random() % NUM_DISPLAY_MODES; } pp->marks = marks; /* Orientation marks don't make sense in wireframe mode. */ if (pp->display_mode == DISP_WIREFRAME) pp->marks = False; /* Set the appearance. */ if (!strcasecmp(appear,"random")) { pp->appearance = random() % NUM_APPEARANCES; } else if (!strcasecmp(appear,"solid")) { pp->appearance = APPEARANCE_SOLID; } else if (!strcasecmp(appear,"distance-bands")) { pp->appearance = APPEARANCE_DISTANCE_BANDS; } else if (!strcasecmp(appear,"direction-bands")) { pp->appearance = APPEARANCE_DIRECTION_BANDS; } else { pp->appearance = random() % NUM_APPEARANCES; } /* Set the color mode. */ if (!strcasecmp(color_mode,"random")) { pp->colors = random() % NUM_COLORS; } else if (!strcasecmp(color_mode,"two-sided")) { pp->colors = COLORS_TWOSIDED; } else if (!strcasecmp(color_mode,"distance")) { pp->colors = COLORS_DISTANCE; } else if (!strcasecmp(color_mode,"direction")) { pp->colors = COLORS_DIRECTION; } else { pp->colors = random() % NUM_COLORS; } /* Set the view mode. */ if (!strcasecmp(view_mode,"random")) { pp->view = random() % NUM_VIEW_MODES; } else if (!strcasecmp(view_mode,"walk")) { pp->view = VIEW_WALK; } else if (!strcasecmp(view_mode,"turn")) { pp->view = VIEW_TURN; } else { pp->view = random() % NUM_VIEW_MODES; } /* Set the 3d projection mode. */ if (!strcasecmp(proj,"random")) { /* Orthographic projection only makes sense in turn mode. */ if (pp->view == VIEW_TURN) pp->projection = random() % NUM_DISP_MODES; else pp->projection = DISP_PERSPECTIVE; } else if (!strcasecmp(proj,"perspective")) { pp->projection = DISP_PERSPECTIVE; } else if (!strcasecmp(proj,"orthographic")) { pp->projection = DISP_ORTHOGRAPHIC; } else { /* Orthographic projection only makes sense in turn mode. */ if (pp->view == VIEW_TURN) pp->projection = random() % NUM_DISP_MODES; else pp->projection = DISP_PERSPECTIVE; } /* make multiple screens rotate at slightly different rates. */ pp->speed_scale = 0.9 + frand(0.3); if ((pp->glx_context = init_GL(mi)) != NULL) { reshape_romanboy(mi,MI_WIDTH(mi),MI_HEIGHT(mi)); glDrawBuffer(GL_BACK); init(mi); } else { MI_CLEARWINDOW(mi); } } /* *----------------------------------------------------------------------------- * Called by the mainline code periodically to update the display. *----------------------------------------------------------------------------- */ ENTRYPOINT void draw_romanboy(ModeInfo *mi) { Display *display = MI_DISPLAY(mi); Window window = MI_WINDOW(mi); romanboystruct *pp; if (romanboy == NULL) return; pp = &romanboy[MI_SCREEN(mi)]; MI_IS_DRAWN(mi) = True; if (!pp->glx_context) return; glXMakeCurrent(display, window, *pp->glx_context); glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT); glLoadIdentity(); display_romanboy(mi); if (MI_IS_FPS(mi)) do_fps (mi); glFlush(); glXSwapBuffers(display,window); } /* *----------------------------------------------------------------------------- * The display is being taken away from us. Free up malloc'ed * memory and X resources that we've alloc'ed. *----------------------------------------------------------------------------- */ ENTRYPOINT void free_romanboy(ModeInfo *mi) { romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; if (!pp->glx_context) return; glXMakeCurrent (MI_DISPLAY(mi), MI_WINDOW(mi), *pp->glx_context); if (pp->pp) free(pp->pp); if (pp->pn) free(pp->pn); if (pp->col) free(pp->col); if (pp->tex) free(pp->tex); gltrackball_free (pp->trackball); if (pp->tex_name) glDeleteTextures (1, &pp->tex_name); } #ifndef STANDALONE ENTRYPOINT void change_romanboy(ModeInfo *mi) { romanboystruct *pp = &romanboy[MI_SCREEN(mi)]; if (!pp->glx_context) return; glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *pp->glx_context); init(mi); } #endif /* !STANDALONE */ XSCREENSAVER_MODULE ("RomanBoy", romanboy) #endif /* USE_GL */