Original 5.40

1 files changed, 219 insertions, 0 deletions

diff --git a/hacks/glx/b_sphere.c b/hacks/glx/b_sphere.c
new file mode 100644
index 0000000..78be392
--- /dev/null
+++ b/hacks/glx/b_sphere.c
@@ -0,0 +1,219 @@
+#if 0
+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"
+
+typedef glb_vertex vertex;
+typedef glb_triangle triangle;
+
+struct glb_data {
+
+  /* The list of vertices created. */
+  vertex *vertices;
+  int nr_vertices, nr_vertices_allocated;
+
+  /* The list of triangles created. */
+  triangle *triangles;
+  int nr_triangles, nr_triangles_allocated;
+};
+
+
+#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(const GLfloat * v1, const 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(glb_data *d, const 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 < d->nr_vertices; ++i)
+		if (close_enough(v, d->vertices[i]))
+			return i;
+
+	if (d->nr_vertices_allocated <= d->nr_vertices) {
+		if (d->vertices == 0) {
+			d->vertices = (vertex *) malloc(INCR(d->nr_vertices_allocated) * sizeof (vertex));
+		} else {
+			INCR_ALLOCATION(d->vertices, d->nr_vertices_allocated, vertex);
+		}
+	}
+	d->vertices[d->nr_vertices][0] = v[0];
+	d->vertices[d->nr_vertices][1] = v[1];
+	d->vertices[d->nr_vertices][2] = v[2];
+	return d->nr_vertices++;
+}
+
+static inline GLuint
+save_triangle(glb_data *d, GLuint v1, GLuint v2, GLuint v3)
+{
+	if (d->nr_triangles_allocated <= d->nr_triangles) {
+		if (d->triangles == 0) {
+			d->triangles = (triangle *) malloc(INCR(d->nr_triangles_allocated) * sizeof (triangle));
+		} else {
+			INCR_ALLOCATION(d->triangles, d->nr_triangles_allocated, triangle);
+		}
+	}
+	d->triangles[d->nr_triangles][0] = v1;
+	d->triangles[d->nr_triangles][1] = v2;
+	d->triangles[d->nr_triangles][2] = v3;
+	return d->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(glb_data *d,
+          const GLfloat * v1, GLuint vi1,
+	  const GLfloat * v2, GLuint vi2,
+	  const GLfloat * v3, GLuint vi3,
+	  int depth)
+{
+	int         i;
+
+	if (depth == 0) {
+		save_triangle(d, 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(d, v12);
+		normalize(v23);
+		vi23 = save_vertex(d, v23);
+		normalize(v31);
+		vi31 = save_vertex(d, v31);
+		subdivide(d, v1, vi1, v12, vi12, v31, vi31, depth - 1);
+		subdivide(d, v2, vi2, v23, vi23, v12, vi12, depth - 1);
+		subdivide(d, v3, vi3, v31, vi31, v23, vi23, depth - 1);
+		subdivide(d, v12, vi12, v23, vi23, v31, vi31, depth - 1);
+	}
+}
+
+#define ICO_X 0.525731112119133606
+#define ICO_Z 0.850650808352039932
+
+static const 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 const 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. */
+glb_data *
+glb_sphere_init(void)
+{
+        glb_data *d = (glb_data *) calloc (1, sizeof (*d));
+	int         i;
+
+	for (i = 0; i < 20; ++i) {
+		subdivide(d, vdata[tindices[i][0]], save_vertex(d, vdata[tindices[i][0]]),
+		   vdata[tindices[i][1]], save_vertex(d, vdata[tindices[i][1]]),
+		   vdata[tindices[i][2]], save_vertex(d, vdata[tindices[i][2]]),
+			  glb_config.subdivision_depth);
+	}
+
+	return d;
+}
+
+/* Return the vertices list. */
+glb_vertex *
+glb_sphere_get_vertices(glb_data *d, int *nr_vertices_ptr)
+{
+	*nr_vertices_ptr = d->nr_vertices;
+	return d->vertices;
+}
+
+/* Return the triangles list. */
+glb_triangle *
+glb_sphere_get_triangles(glb_data *d, int *nr_triangles_ptr)
+{
+	*nr_triangles_ptr = d->nr_triangles;
+	return d->triangles;
+}
+
+/* Free up memory. */
+void
+glb_sphere_end(glb_data *d)
+{
+	(void) free((void *) d->vertices);
+	(void) free((void *) d->triangles);
+        free (d);
+}