http://ftp.x.org/contrib/applications/xscreensaver-3.19.tar.gz

[xscreensaver] / hacks / glx / extrusion-screw.c

diff --git a/hacks/glx/extrusion-screw.c b/hacks/glx/extrusion-screw.c
new file mode 100644 (file)
index 0000000..16f12b1
--- /dev/null
+++ b/hacks/glx/extrusion-screw.c
@@ -0,0 +1,126 @@
+/* 
+ * screw.c
+ * 
+ * FUNCTION:
+ * Draws a screw shape.
+ *
+ * HISTORY:
+ * -- created by Linas Vepstas October 1991
+ * -- heavily modified to draw more texas shapes, Feb 1993, Linas
+ * -- converted to use GLUT -- December 1995, Linas
+ *
+ */
+
+/* required include files */
+#include <math.h>
+#include <stdlib.h>
+#include <GL/gl.h>
+#include <GL/glut.h>
+#include <GL/tube.h>
+
+#ifndef NULL
+#define NULL ((void *) 0x0)
+#endif /* NULL */
+
+/* =========================================================== */
+
+#define SCALE 1.3
+#define CONTOUR(x,y) {                                 \
+   double ax, ay, alen;                                        \
+   contour[i][0] = SCALE * (x);                                \
+   contour[i][1] = SCALE * (y);                                \
+   if (i!=0) {                                         \
+      ax = contour[i][0] - contour[i-1][0];            \
+      ay = contour[i][1] - contour[i-1][1];            \
+      alen = 1.0 / sqrt (ax*ax + ay*ay);               \
+      ax *= alen;   ay *= alen;                                \
+      norms [i-1][0] = ay;                             \
+      norms [i-1][1] = -ax;                            \
+   }                                                   \
+   i++;                                                        \
+}
+
+#define NUM_PTS (25)
+
+double contour [NUM_PTS][2];
+double norms [NUM_PTS][2];
+
+static void init_contour (void)
+{
+   int i;
+
+   /* outline of extrusion */
+   i=0;
+   CONTOUR (1.0, 1.0);
+   CONTOUR (1.0, 2.9);
+   CONTOUR (0.9, 3.0);
+   CONTOUR (-0.9, 3.0);
+   CONTOUR (-1.0, 2.9);
+
+   CONTOUR (-1.0, 1.0);
+   CONTOUR (-2.9, 1.0);
+   CONTOUR (-3.0, 0.9);
+   CONTOUR (-3.0, -0.9);
+   CONTOUR (-2.9, -1.0);
+
+   CONTOUR (-1.0, -1.0);
+   CONTOUR (-1.0, -2.9);
+   CONTOUR (-0.9, -3.0);
+   CONTOUR (0.9, -3.0);
+   CONTOUR (1.0, -2.9);
+
+   CONTOUR (1.0, -1.0);
+   CONTOUR (2.9, -1.0);
+   CONTOUR (3.0, -0.9);
+   CONTOUR (3.0, 0.9);
+   CONTOUR (2.9, 1.0);
+
+   CONTOUR (1.0, 1.0);   /* repeat so that last normal is computed */
+}
+   
+/* =========================================================== */
+
+extern float lastx;
+extern float lasty;
+extern float rot_x;
+extern float rot_y;
+extern float rot_z;
+
+void InitStuff_screw (void)
+{
+   int style;
+
+   /* configure the pipeline */
+   style = TUBE_JN_CAP;
+   style |= TUBE_CONTOUR_CLOSED;
+   style |= TUBE_NORM_FACET;
+   style |= TUBE_JN_ANGLE;
+   gleSetJoinStyle (style);
+
+   init_contour();
+}
+
+/* =========================================================== */
+
+void DrawStuff_screw (void) {
+
+   glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+   glColor3f (0.5, 0.6, 0.6);
+
+   /* set up some matrices so that the object spins with the mouse */
+   glPushMatrix ();
+   glTranslatef (0.0, 0.0, -80.0);
+   glRotatef(rot_x, 1, 0, 0);
+   glRotatef(rot_y, 0, 1, 0);
+   glRotatef(rot_z, 0, 0, 1);
+/*     glRotatef (130.0, 0.0, 1.0, 0.0); */
+/*     glRotatef (65.0, 1.0, 0.0, 0.0); */
+
+   /* draw the brand and the handle */
+   gleScrew (20, contour, norms, 
+                 NULL, -6.0, 9.0, lasty);
+
+   glPopMatrix ();
+}
+
+/* ===================== END OF FILE ================== */