--- /dev/null
+#if !defined( lint ) && !defined( SABER )
+static const char sccsid[] = "@(#)b_sphere.c 4.11 98/06/16 xlockmore";
+
+#endif
+
+/*-
+ * BUBBLE3D (C) 1998 Richard W.M. Jones.
+ * b_sphere.c: Create a list of vertices and triangles in a
+ * normalized sphere, which is then later used as the basic shape
+ * for all bubbles. This code is run once when the program starts
+ * up.
+ */
+
+#include "bubble3d.h"
+
+/* The list of vertices created. */
+typedef glb_vertex vertex;
+static vertex *vertices = 0;
+static int nr_vertices = 0, nr_vertices_allocated = 0;
+
+/* The list of triangles created. */
+typedef glb_triangle triangle;
+static triangle *triangles = 0;
+static int nr_triangles = 0, nr_triangles_allocated = 0;
+
+/* Have we initialized the lists yet? */
+static int initialized = 0;
+
+#define EPSILON GLB_VERTICES_EPSILON
+
+/* Should be taken care of already... but just in case */
+#if !defined( __GNUC__ ) && !defined(__cplusplus) && !defined(c_plusplus)
+#undef inline
+#define inline /* */
+#endif
+static inline int
+close_enough(GLfloat * v1, GLfloat * v2)
+{
+ return fabs((double) (v1[0] - v2[0])) <= EPSILON &&
+ fabs((double) (v1[1] - v2[1])) <= EPSILON &&
+ fabs((double) (v1[2] - v2[2])) <= EPSILON;
+}
+
+#define INCR(n) ((n == 0) ? (n = 1) : (n *= 2))
+#define INCR_ALLOCATION(a, n, t) (a = (t *) realloc (a, INCR (n) * sizeof (t)))
+
+static inline GLuint
+save_vertex(GLfloat * v)
+{
+ int i;
+
+ /* Inefficient, but we only do this a few times. Check to see if there's
+ * an existing vertex which is `close enough' to this one.
+ */
+ for (i = 0; i < nr_vertices; ++i)
+ if (close_enough(v, vertices[i]))
+ return i;
+
+ if (nr_vertices_allocated <= nr_vertices) {
+ if (vertices == 0) {
+ vertices = (vertex *) malloc(INCR(nr_vertices_allocated) * sizeof (vertex));
+ } else {
+ INCR_ALLOCATION(vertices, nr_vertices_allocated, vertex);
+ }
+ }
+ vertices[nr_vertices][0] = v[0];
+ vertices[nr_vertices][1] = v[1];
+ vertices[nr_vertices][2] = v[2];
+ return nr_vertices++;
+}
+
+static inline GLuint
+save_triangle(GLuint v1, GLuint v2, GLuint v3)
+{
+ if (nr_triangles_allocated <= nr_triangles) {
+ if (triangles == 0) {
+ triangles = (triangle *) malloc(INCR(nr_triangles_allocated) * sizeof (triangle));
+ } else {
+ INCR_ALLOCATION(triangles, nr_triangles_allocated, triangle);
+ }
+ }
+ triangles[nr_triangles][0] = v1;
+ triangles[nr_triangles][1] = v2;
+ triangles[nr_triangles][2] = v3;
+ return nr_triangles++;
+}
+
+static inline void
+normalize(GLfloat v[3])
+{
+ GLfloat d = (GLfloat) sqrt((double) (v[0] * v[0] + v[1] * v[1] + v[2] * v[2]));
+
+ if (d != 0) {
+ v[0] /= d;
+ v[1] /= d;
+ v[2] /= d;
+ } else {
+ v[0] = v[1] = v[2] = 0;
+ }
+}
+
+static void
+subdivide(GLfloat * v1, GLuint vi1,
+ GLfloat * v2, GLuint vi2,
+ GLfloat * v3, GLuint vi3,
+ int depth)
+{
+ int i;
+
+ if (depth == 0) {
+ save_triangle(vi1, vi2, vi3);
+ } else {
+ GLuint vi12, vi23, vi31;
+ GLfloat v12[3], v23[3], v31[3];
+
+ for (i = 0; i < 3; ++i) {
+ v12[i] = v1[i] + v2[i];
+ v23[i] = v2[i] + v3[i];
+ v31[i] = v3[i] + v1[i];
+ }
+ normalize(v12);
+ vi12 = save_vertex(v12);
+ normalize(v23);
+ vi23 = save_vertex(v23);
+ normalize(v31);
+ vi31 = save_vertex(v31);
+ subdivide(v1, vi1, v12, vi12, v31, vi31, depth - 1);
+ subdivide(v2, vi2, v23, vi23, v12, vi12, depth - 1);
+ subdivide(v3, vi3, v31, vi31, v23, vi23, depth - 1);
+ subdivide(v12, vi12, v23, vi23, v31, vi31, depth - 1);
+ }
+}
+
+#define ICO_X 0.525731112119133606
+#define ICO_Z 0.850650808352039932
+
+static GLfloat vdata[12][3] =
+{
+ {-ICO_X, 0, ICO_Z},
+ {ICO_X, 0, ICO_Z},
+ {-ICO_X, 0, -ICO_Z},
+ {ICO_X, 0, -ICO_Z},
+ {0, ICO_Z, ICO_X},
+ {0, ICO_Z, -ICO_X},
+ {0, -ICO_Z, ICO_X},
+ {0, -ICO_Z, -ICO_X},
+ {ICO_Z, ICO_X, 0},
+ {-ICO_Z, ICO_X, 0},
+ {ICO_Z, -ICO_X, 0},
+ {-ICO_Z, -ICO_X, 0}
+};
+
+static GLuint tindices[20][3] =
+{
+ {0, 4, 1},
+ {0, 9, 4},
+ {9, 5, 4},
+ {4, 5, 8},
+ {4, 8, 1},
+ {8, 10, 1},
+ {8, 3, 10},
+ {5, 3, 8},
+ {5, 2, 3},
+ {2, 7, 3},
+ {7, 10, 3},
+ {7, 6, 10},
+ {7, 11, 6},
+ {11, 0, 6},
+ {0, 1, 6},
+ {6, 1, 10},
+ {9, 0, 11},
+ {9, 11, 2},
+ {9, 2, 5},
+ {7, 2, 11}
+};
+
+/* Public interface: Create the sphere. */
+void
+glb_sphere_init(void)
+{
+ int i;
+
+ if (initialized)
+ return;
+
+ for (i = 0; i < 20; ++i) {
+ subdivide(vdata[tindices[i][0]], save_vertex(vdata[tindices[i][0]]),
+ vdata[tindices[i][1]], save_vertex(vdata[tindices[i][1]]),
+ vdata[tindices[i][2]], save_vertex(vdata[tindices[i][2]]),
+ glb_config.subdivision_depth);
+ }
+
+ initialized = 1;
+}
+
+/* Return the vertices list. */
+glb_vertex *
+glb_sphere_get_vertices(int *nr_vertices_ptr)
+{
+ glb_sphere_init();
+ *nr_vertices_ptr = nr_vertices;
+ return vertices;
+}
+
+/* Return the triangles list. */
+glb_triangle *
+glb_sphere_get_triangles(int *nr_triangles_ptr)
+{
+ glb_sphere_init();
+ *nr_triangles_ptr = nr_triangles;
+ return triangles;
+}
+
+/* Free up memory. */
+#if 0
+void
+glb_sphere_end(void)
+{
+ initialized = 0;
+
+ (void) free((void *) vertices);
+ (void) free((void *) triangles);
+
+ vertices = 0;
+ nr_vertices = nr_vertices_allocated = 0;
+
+ triangles = 0;
+ nr_triangles = nr_triangles_allocated = 0;
+}
+
+#endif
projects / xscreensaver / blobdiff