X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?p=xscreensaver;a=blobdiff_plain;f=hacks%2Fglx%2Fsierpinski3d.c;h=d11daf1aeed98a98498b861af1262f56744baff5;hp=9a783a04794600165780e6b80f64ef05f3fa6b53;hb=06e9a7886a77cad92f9ddbc169d6d199a4d8b76d;hpb=14463b6ad1ab1ccf81f9c33350b048e410ba94cb diff --git a/hacks/glx/sierpinski3d.c b/hacks/glx/sierpinski3d.c index 9a783a04..d11daf1a 100644 --- a/hacks/glx/sierpinski3d.c +++ b/hacks/glx/sierpinski3d.c @@ -22,6 +22,9 @@ static const char sccsid[] = "@(#)sierpinski3D.c 00.01 99/11/04 xlockmore"; * Revision History: * 1999: written by Tim Robinson * a 3-D representation of the Sierpinski gasket fractal. + * + * 10-Dec-99 jwz rewrote to draw a set of tetrahedrons instead of a + * random scattering of points. */ /*- @@ -38,7 +41,9 @@ static const char sccsid[] = "@(#)sierpinski3D.c 00.01 99/11/04 xlockmore"; # define gasket_opts xlockmore_opts # define DEFAULTS "*count: 1 \n" \ "*cycles: 9999 \n" \ - "*delay: 100 \n" \ + "*delay: 8000 \n" \ + "*maxDepth: 5 \n" \ + "*speed: 150 \n" \ "*wireframe: False \n" # include "xlockmore.h" /* from the xscreensaver distribution */ #else /* !STANDALONE */ @@ -47,8 +52,23 @@ static const char sccsid[] = "@(#)sierpinski3D.c 00.01 99/11/04 xlockmore"; #ifdef USE_GL -ModeSpecOpt gasket_opts = -{0, NULL, 0, NULL, NULL}; +#undef countof +#define countof(x) (sizeof((x))/sizeof((*x))) + +static int max_depth; +static int speed; +static XrmOptionDescRec opts[] = { + {"-depth", ".sierpinski3d.maxDepth", XrmoptionSepArg, (caddr_t) 0 }, + {"-speed", ".sierpinski3d.speed", XrmoptionSepArg, (caddr_t) 0 } +}; + +static argtype vars[] = { + {(caddr_t *) &max_depth, "maxDepth", "MaxDepth", "5", t_Int}, + {(caddr_t *) &speed, "speed", "Speed", "150", t_Int}, +}; + + +ModeSpecOpt gasket_opts = {countof(opts), opts, countof(vars), vars, NULL}; #ifdef USE_MODULES ModStruct gasket_description = @@ -74,9 +94,9 @@ typedef struct { GLuint gasket1; GLXContext *glx_context; Window window; -#if 0 - Window win; -#endif + + int current_depth; + } gasketstruct; static gasketstruct *gasket = NULL; @@ -85,11 +105,205 @@ static gasketstruct *gasket = NULL; /* static GLuint limit; */ + +/* Computing normal vectors (thanks to Nat Friedman ) + */ + +typedef struct vector { + GLfloat x, y, z; +} vector; + +typedef struct plane { + vector p1, p2, p3; +} plane; + +static void +vector_set(vector *v, GLfloat x, GLfloat y, GLfloat z) +{ + v->x = x; + v->y = y; + v->z = z; +} + +static void +vector_cross(vector v1, vector v2, vector *v3) +{ + v3->x = (v1.y * v2.z) - (v1.z * v2.y); + v3->y = (v1.z * v2.x) - (v1.x * v2.z); + v3->z = (v1.x * v2.y) - (v1.y * v2.x); +} + +static void +vector_subtract(vector v1, vector v2, vector *res) +{ + res->x = v1.x - v2.x; + res->y = v1.y - v2.y; + res->z = v1.z - v2.z; +} + +static void +plane_normal(plane p, vector *n) +{ + vector v1, v2; + vector_subtract(p.p1, p.p2, &v1); + vector_subtract(p.p1, p.p3, &v2); + vector_cross(v2, v1, n); +} + +static void +do_normal(GLfloat x1, GLfloat y1, GLfloat z1, + GLfloat x2, GLfloat y2, GLfloat z2, + GLfloat x3, GLfloat y3, GLfloat z3) +{ + plane plane; + vector n; + vector_set(&plane.p1, x1, y1, z1); + vector_set(&plane.p2, x2, y2, z2); + vector_set(&plane.p3, x3, y3, z3); + plane_normal(plane, &n); + n.x = -n.x; n.y = -n.y; n.z = -n.z; + + glNormal3f(n.x, n.y, n.z); + +#ifdef DEBUG + /* Draw a line in the direction of this face's normal. */ + { + GLfloat ax = n.x > 0 ? n.x : -n.x; + GLfloat ay = n.y > 0 ? n.y : -n.y; + GLfloat az = n.z > 0 ? n.z : -n.z; + GLfloat mx = (x1 + x2 + x3) / 3; + GLfloat my = (y1 + y2 + y3) / 3; + GLfloat mz = (z1 + z2 + z3) / 3; + GLfloat xx, yy, zz; + + GLfloat max = ax > ay ? ax : ay; + if (az > max) max = az; + max *= 2; + xx = n.x / max; + yy = n.y / max; + zz = n.z / max; + + glBegin(GL_LINE_LOOP); + glVertex3f(mx, my, mz); + glVertex3f(mx+xx, my+yy, mz+zz); + glEnd(); + } +#endif /* DEBUG */ +} + + + +static void +triangle (GLfloat x1, GLfloat y1, GLfloat z1, + GLfloat x2, GLfloat y2, GLfloat z2, + GLfloat x3, GLfloat y3, GLfloat z3, + Bool wireframe_p) +{ + if (wireframe_p) + glBegin (GL_LINE_LOOP); + else + { + do_normal (x1, y1, z1, x2, y2, z2, x3, y3, z3); + glBegin (GL_TRIANGLES); + } + glVertex3f (x1, y1, z1); + glVertex3f (x2, y2, z2); + glVertex3f (x3, y3, z3); + glEnd(); +} + +static void +four_tetras (GL_VECTOR *outer, Bool wireframe_p, int countdown) +{ + if (countdown <= 0) + { + triangle (outer[0].x, outer[0].y, outer[0].z, + outer[1].x, outer[1].y, outer[1].z, + outer[2].x, outer[2].y, outer[2].z, + wireframe_p); + triangle (outer[0].x, outer[0].y, outer[0].z, + outer[3].x, outer[3].y, outer[3].z, + outer[1].x, outer[1].y, outer[1].z, + wireframe_p); + triangle (outer[0].x, outer[0].y, outer[0].z, + outer[2].x, outer[2].y, outer[2].z, + outer[3].x, outer[3].y, outer[3].z, + wireframe_p); + triangle (outer[1].x, outer[1].y, outer[1].z, + outer[3].x, outer[3].y, outer[3].z, + outer[2].x, outer[2].y, outer[2].z, + wireframe_p); + } + else + { +# define M01 0 +# define M02 1 +# define M03 2 +# define M12 3 +# define M13 4 +# define M23 5 + GL_VECTOR inner[M23+1]; + GL_VECTOR corner[4]; + + inner[M01].x = (outer[0].x + outer[1].x) / 2.0; + inner[M01].y = (outer[0].y + outer[1].y) / 2.0; + inner[M01].z = (outer[0].z + outer[1].z) / 2.0; + + inner[M02].x = (outer[0].x + outer[2].x) / 2.0; + inner[M02].y = (outer[0].y + outer[2].y) / 2.0; + inner[M02].z = (outer[0].z + outer[2].z) / 2.0; + + inner[M03].x = (outer[0].x + outer[3].x) / 2.0; + inner[M03].y = (outer[0].y + outer[3].y) / 2.0; + inner[M03].z = (outer[0].z + outer[3].z) / 2.0; + + inner[M12].x = (outer[1].x + outer[2].x) / 2.0; + inner[M12].y = (outer[1].y + outer[2].y) / 2.0; + inner[M12].z = (outer[1].z + outer[2].z) / 2.0; + + inner[M13].x = (outer[1].x + outer[3].x) / 2.0; + inner[M13].y = (outer[1].y + outer[3].y) / 2.0; + inner[M13].z = (outer[1].z + outer[3].z) / 2.0; + + inner[M23].x = (outer[2].x + outer[3].x) / 2.0; + inner[M23].y = (outer[2].y + outer[3].y) / 2.0; + inner[M23].z = (outer[2].z + outer[3].z) / 2.0; + + countdown--; + + corner[0] = outer[0]; + corner[1] = inner[M01]; + corner[2] = inner[M02]; + corner[3] = inner[M03]; + four_tetras (corner, wireframe_p, countdown); + + corner[0] = inner[M01]; + corner[1] = outer[1]; + corner[2] = inner[M12]; + corner[3] = inner[M13]; + four_tetras (corner, wireframe_p, countdown); + + corner[0] = inner[M02]; + corner[1] = inner[M12]; + corner[2] = outer[2]; + corner[3] = inner[M23]; + four_tetras (corner, wireframe_p, countdown); + + corner[0] = inner[M03]; + corner[1] = inner[M13]; + corner[2] = inner[M23]; + corner[3] = outer[3]; + four_tetras (corner, wireframe_p, countdown); + } +} + + static void compile_gasket(ModeInfo *mi) { - int i,p; - int points = MI_CYCLES(mi) ? MI_CYCLES(mi) : 9999; + Bool wireframe_p = MI_IS_WIREFRAME(mi); + gasketstruct *gp = &gasket[MI_SCREEN(mi)]; + GL_VECTOR vertex[5]; /* define verticies */ @@ -113,30 +327,38 @@ compile_gasket(ModeInfo *mi) vertex[4].y = 0.0; vertex[4].z = 0.0; - glBegin(GL_POINTS); - for( i = 0; i < points ; i++ ) - { - p = NRAND(4); - vertex[4].x = ( vertex[4].x + vertex[p].x )/2.0; - vertex[4].y = ( vertex[4].y + vertex[p].y )/2.0; - vertex[4].z = ( vertex[4].z + vertex[p].z )/2.0; - - glVertex4f( vertex[4].x, vertex[4].y, vertex[4].z, 1.0 ); - } - glEnd(); + four_tetras (vertex, wireframe_p, + (gp->current_depth < 0 + ? -gp->current_depth : gp->current_depth)); } static void draw(ModeInfo *mi) { gasketstruct *gp = &gasket[MI_SCREEN(mi)]; + static int tick = 0; - glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + static float position0[] = {-0.5, 1.2, 0.5, 0.0}; + static float ambient0[] = {0.4, 0.6, 0.4, 1.0}; + static float spec[] = {0.7, 0.7, 0.7, 1.0}; + static float shine[] = {70.0}; + + glLightfv(GL_LIGHT0, GL_POSITION, position0); + glLightfv(GL_LIGHT0, GL_AMBIENT, ambient0); + glLightfv(GL_LIGHT0, GL_SPECULAR, spec); + glLightfv(GL_LIGHT0, GL_SHININESS, shine); + glLightfv(GL_LIGHT0, GL_DIFFUSE, gp->light_colour); + + glShadeModel(GL_SMOOTH); - glLightfv(GL_LIGHT0, GL_AMBIENT, gp->light_colour); glEnable(GL_LIGHTING); glEnable(GL_LIGHT0); + glEnable(GL_DEPTH_TEST); + glEnable(GL_NORMALIZE); + glEnable(GL_CULL_FACE); + + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glPushMatrix(); glTranslatef( gp->pos[0], gp->pos[1], gp->pos[2] ); @@ -152,6 +374,24 @@ draw(ModeInfo *mi) glPopMatrix(); + + if (tick++ >= speed) + { + tick = 0; + if (gp->current_depth >= max_depth) + gp->current_depth = -max_depth; + gp->current_depth++; + + glDeleteLists (gp->gasket1, 1); + glNewList (gp->gasket1, GL_COMPILE); + compile_gasket (mi); + glEndList(); + + /* do the colour change */ + gp->light_colour[0] = 3.0*SINF(gp->angle/20.0) + 4.0; + gp->light_colour[1] = 3.0*SINF(gp->angle/30.0) + 4.0; + gp->light_colour[2] = 3.0*SINF(gp->angle/60.0) + 4.0; + } } @@ -171,7 +411,7 @@ reshape(int width, int height) 0.0, 1.0, 0.0); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); - glTranslatef(0.0, 0.0, -40.0); + glTranslatef(0.0, 0.0, -15.0); /* The depth buffer will be cleared, if needed, before the * next frame. Right now we just want to black the screen. @@ -196,6 +436,7 @@ pinit(ModeInfo *mi) gp->pos[2] = 0.0; /* draw the gasket */ gp->gasket1 = glGenLists(1); + gp->current_depth = 1; /* start out at level 1, not 0 */ glNewList(gp->gasket1, GL_COMPILE); compile_gasket(mi); glEndList(); @@ -245,16 +486,16 @@ draw_gasket(ModeInfo * mi) glDrawBuffer(GL_BACK); + if (max_depth > 10) + max_depth = 10; + glXMakeCurrent(display, window, *(gp->glx_context)); draw(mi); - /* do the colour change & movement thing */ + /* rotate */ gp->angle = (int) (gp->angle + angle_incr) % 360; - gp->light_colour[0] = 3.0*SINF(gp->angle/20.0) + 4.0; - gp->light_colour[1] = 3.0*SINF(gp->angle/30.0) + 4.0; - gp->light_colour[2] = 3.0*SINF(gp->angle/60.0) + 4.0; - if ( FABSF( gp->pos[0] ) > 9.0 ) gp->xinc = -1.0 * gp->xinc; - if ( FABSF( gp->pos[1] ) > 7.0 ) gp->yinc = -1.0 * gp->yinc; + if ( FABSF( gp->pos[0] ) > 8.0 ) gp->xinc = -1.0 * gp->xinc; + if ( FABSF( gp->pos[1] ) > 6.0 ) gp->yinc = -1.0 * gp->yinc; if ( FABSF( gp->pos[2] ) >15.0 ) gp->zinc = -1.0 * gp->zinc; gp->pos[0] += gp->xinc; gp->pos[1] += gp->yinc;