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Diffstat (limited to 'hacks/glx/extrusion-twistoid.c')
| -rw-r--r-- | hacks/glx/extrusion-twistoid.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/hacks/glx/extrusion-twistoid.c b/hacks/glx/extrusion-twistoid.c new file mode 100644 index 0000000..82034af --- /dev/null +++ b/hacks/glx/extrusion-twistoid.c @@ -0,0 +1,215 @@ +/* + * twistoid.c + * + * FUNCTION: + * Show extrusion of open contours. Also, show how torsion is applied. + * + * HISTORY: + * -- linas Vepstas October 1991 + * -- heavily modified to draw corrugated surface, Feb 1993, Linas + * -- modified to demo twistoid March 1993 + * -- port to glut Linas Vepstas March 1995 + */ + +#include "extrusion.h" + +#include <math.h> +#include <stdlib.h> + +/* Some <math.h> files do not define M_PI... */ +#ifndef M_PI +#define M_PI 3.14159265358979323846 +#endif + +/* controls shape of object */ +extern float lastx; +extern float lasty; + +#define OPENGL_10 +/* =========================================================== */ + +#define NUM_TOID1_PTS 5 +static double toid1_points[NUM_TOID1_PTS][3]; +static float toid1_colors [NUM_TOID1_PTS][3]; +static double toid1_twists [NUM_TOID1_PTS]; + +#define TSCALE (6.0) + +#define TPTS(x,y) { \ + toid1_points[i][0] = TSCALE * (x); \ + toid1_points[i][1] = TSCALE * (y); \ + toid1_points[i][2] = TSCALE * (0.0); \ + i++; \ +} + +#define TCOLS(r,g,b) { \ + toid1_colors[i][0] = (r); \ + toid1_colors[i][1] = (g); \ + toid1_colors[i][2] = (b); \ + i++; \ +} + +#define TXZERO() { \ + toid1_twists[i] = 0.0; \ + i++; \ +} + +static void init_toid1_line (void) +{ + int i; + + i=0; + TPTS (-1.1, 0.0); + TPTS (-1.0, 0.0); + TPTS (0.0, 0.0); + TPTS (1.0, 0.0); + TPTS (1.1, 0.0); + + i=0; + TCOLS (0.8, 0.8, 0.5); + TCOLS (0.8, 0.4, 0.5); + TCOLS (0.8, 0.8, 0.3); + TCOLS (0.4, 0.4, 0.5); + TCOLS (0.8, 0.8, 0.5); + + i=0; + TXZERO (); + TXZERO (); + TXZERO (); + TXZERO (); + TXZERO (); +} + +/* =========================================================== */ + +#define SCALE 0.6 +#define TWIST(x,y) { \ + double ax, ay, alen; \ + twistation[i][0] = SCALE * (x); \ + twistation[i][1] = SCALE * (y); \ + if (i!=0) { \ + ax = twistation[i][0] - twistation[i-1][0]; \ + ay = twistation[i][1] - twistation[i-1][1]; \ + alen = 1.0 / sqrt (ax*ax + ay*ay); \ + ax *= alen; ay *= alen; \ + twist_normal [i-1][0] = - ay; \ + twist_normal [i-1][1] = ax; \ + } \ + i++; \ +} + +#define NUM_TWIS_PTS (20) + +static double twistation [NUM_TWIS_PTS][2]; +static double twist_normal [NUM_TWIS_PTS][2]; + +static void init_tripples (void) +{ + int i; + double angle; + double co, si; + + /* outline of extrusion */ + i=0; + /* first, draw a semi-curcular "hump" */ + while (i< 11) { + angle = M_PI * ((double) i) / 10.0; + co = cos (angle); + si = sin (angle); + TWIST ((-7.0 -3.0*co), 1.8*si); + } + + /* now, a zig-zag corrugation */ + while (1) { + if (i >= NUM_TWIS_PTS) break; + TWIST ((-10.0 +(double) i), 0.0); + if (i >= NUM_TWIS_PTS) break; + TWIST ((-9.5 +(double) i), 1.0); + } +} + + +/* =========================================================== */ + +#define V3F(x,y,z) { \ + float vvv[3]; \ + vvv[0] = x; vvv[1] = y; vvv[2] = z; v3f (vvv); \ +} + +#define N3F(x,y,z) { \ + float nnn[3]; \ + nnn[0] = x; nnn[1] = y; nnn[2] = z; n3f (nnn); \ +} + +/* =========================================================== */ + +void DrawStuff_twistoid (void) { + int i; + + toid1_twists[2] = (lastx-121.0) / 8.0; + + i=3; +/* + TPTS (1.0, lasty /400.0); + TPTS (1.1, 1.1 * lasty / 400.0); +*/ + TPTS (1.0, -(lasty-121.0) /200.0); + TPTS (1.1, -1.1 * (lasty-121.0) / 200.0); + +#ifdef IBM_GL_32 + rotate (230, 'x'); + rotate (230, 'y'); + scale (1.8, 1.8, 1.8); + + if (mono_color) { + RGBcolor (178, 178, 204); + twist_extrusion (NUM_TWIS_PTS, twistation, twist_normal, + NULL, NUM_TOID1_PTS, toid1_points, NULL, toid1_twists); + } else { + twist_extrusion (NUM_TWIS_PTS, twistation, twist_normal, + NULL, NUM_TOID1_PTS, toid1_points, toid1_colors, toid1_twists); + } +#endif + +#ifdef OPENGL_10 + glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + + glFrontFace(GL_CW); /* jwz */ + + /* set up some matrices so that the object spins with the mouse */ + glPushMatrix (); +/* glTranslatef (0.0, 0.0, -80.0); */ +/* glRotated (43.0, 1.0, 0.0, 0.0); */ +/* glRotated (43.0, 0.0, 1.0, 0.0); */ + glScaled (1.8, 1.8, 1.8); + gleTwistExtrusion (NUM_TWIS_PTS, twistation, twist_normal, + NULL, NUM_TOID1_PTS, toid1_points, NULL, toid1_twists); + glPopMatrix (); +#endif + +} + +/* =========================================================== */ + +void InitStuff_twistoid (void) +{ + int js; + + init_toid1_line (); + init_tripples (); + +#ifdef IBM_GL_32 + js = getjoinstyle (); + js &= ~TUBE_CONTOUR_CLOSED; + setjoinstyle (js); +#endif + +#ifdef OPENGL_10 + js = gleGetJoinStyle (); + js &= ~TUBE_CONTOUR_CLOSED; + gleSetJoinStyle (js); +#endif + +} + +/* ------------------ end of file -------------------- */ |