--- /dev/null
+/* -*- Mode: C; tab-width: 4 -*- */
+/* bubble3d.c - 3D bubbles */
+
+#if !defined( lint ) && !defined( SABER )
+static const char sccsid[] = "@(#)bubble3d.c 4.11 98/06/16 xlockmore";
+
+#endif
+
+/*-
+ * BUBBLE3D (C) 1998 Richard W.M. Jones.
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation for any purpose and without fee is hereby granted,
+ * provided that the above copyright notice appear in all copies and that
+ * both that copyright notice and this permission notice appear in
+ * supporting documentation.
+ *
+ * This file is provided AS IS with no warranties of any kind. The author
+ * shall have no liability with respect to the infringement of copyrights,
+ * trade secrets or any patents by this file or any part thereof. In no
+ * event will the author be liable for any lost revenue or profits or
+ * other special, indirect and consequential damages.
+ *
+ * Revision History:
+ * 16-Jun-98: Written.
+ *
+ * bubble.c: This code is responsible for creating and managing
+ * bubbles over their lifetime.
+ * The bubbles may be drawn inside out.
+ */
+
+#include "bubble3d.h"
+
+typedef struct bubble {
+ GLfloat *contributions; /* List of contributions from each
+ * nudge to each vertex. This list has
+ * length nr_vertices * nr_nudge_axes.
+ */
+ GLfloat x, y, z; /* (x,y,z) location of the bubble. */
+ GLfloat scale; /* Scaling factor applied to bubble. */
+ GLfloat y_incr, scale_incr; /* Change in y and scale each frame. */
+ GLfloat rotx, roty, rotz; /* Current rotation. */
+ GLfloat rotx_incr, roty_incr, rotz_incr; /* Amount by which we increase
+ * rotation each step.
+ */
+ GLfloat *nudge_angle; /* Current angle (radians) of each
+ * nudge. This list has length nr_nudge_axes.
+ */
+ GLfloat *nudge_angle_incr; /* Amount by which we increase each nudge
+ * angle in each frame.
+ */
+} bubble;
+
+/* 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 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 inline GLfloat
+dotprod(GLfloat * v1, GLfloat * v2)
+{
+ return v1[0] * v2[0] + v1[1] * v2[1] + v1[2] * v2[2];
+}
+
+static inline GLfloat
+max(GLfloat a, GLfloat b)
+{
+ return a > b ? a : b;
+}
+
+/* Create a new bubble. */
+void *
+glb_bubble_new(GLfloat x, GLfloat y, GLfloat z, GLfloat scale,
+ GLfloat y_incr, GLfloat scale_incr)
+{
+ int i, j;
+
+ /* GLfloat axes [glb_config.nr_nudge_axes][3]; */
+ GLfloat axes[5][3]; /* HARD CODED for SunCC */
+ int nr_vertices;
+ glb_vertex *vertices = glb_sphere_get_vertices(&nr_vertices);
+
+ bubble *b = (bubble *) malloc(sizeof *b);
+
+ if (b == 0)
+ return 0;
+
+ b->contributions = (GLfloat *) malloc(sizeof (GLfloat) * nr_vertices *
+ glb_config.nr_nudge_axes);
+ if (b->contributions == 0) {
+ (void) free((void *) b);
+ return 0;
+ }
+ b->nudge_angle = (GLfloat *) malloc(sizeof (GLfloat) * glb_config.nr_nudge_axes);
+ if (b->nudge_angle == 0) {
+ (void) free((void *) b->contributions);
+ (void) free((void *) b);
+ return 0;
+ }
+ b->nudge_angle_incr = (GLfloat *) malloc(sizeof (GLfloat) * glb_config.nr_nudge_axes);
+ if (b->nudge_angle_incr == 0) {
+ (void) free((void *) b->nudge_angle);
+ (void) free((void *) b->contributions);
+ (void) free((void *) b);
+ return 0;
+ }
+ /* Initialize primitive elements. */
+ b->x = x;
+ b->y = y;
+ b->z = z;
+ b->scale = scale;
+ b->y_incr = y_incr;
+ b->scale_incr = scale_incr;
+ b->rotx = b->roty = b->rotz = 0;
+ b->rotx_incr = glb_drand() * glb_config.rotation_factor * 2
+ - glb_config.rotation_factor;
+ b->roty_incr = glb_drand() * glb_config.rotation_factor * 2
+ - glb_config.rotation_factor;
+ b->rotz_incr = glb_drand() * glb_config.rotation_factor * 2
+ - glb_config.rotation_factor;
+
+ /* Initialize the nudge angle arrays. */
+ for (i = 0; i < glb_config.nr_nudge_axes; ++i) {
+ b->nudge_angle[i] = 0;
+ b->nudge_angle_incr[i] = glb_drand() * glb_config.nudge_angle_factor;
+ }
+
+ /* Choose some random nudge axes. */
+ for (i = 0; i < glb_config.nr_nudge_axes; ++i) {
+ axes[i][0] = glb_drand() * 2 - 1;
+ axes[i][1] = glb_drand() * 2 - 1;
+ axes[i][2] = glb_drand() * 2 - 1;
+ normalize(axes[i]);
+ }
+
+ /* Calculate the contribution that each nudge axis has on each vertex. */
+ for (i = 0; i < nr_vertices; ++i)
+ for (j = 0; j < glb_config.nr_nudge_axes; ++j)
+ b->contributions[i * glb_config.nr_nudge_axes + j]
+ = max(0, dotprod(vertices[i], axes[j]));
+
+ return (void *) b;
+}
+
+/* Delete a bubble and free up all memory. */
+void
+glb_bubble_delete(void *bb)
+{
+ bubble *b = (bubble *) bb;
+
+ if (b != NULL) {
+ if (b->nudge_angle_incr) {
+ (void) free((void *) b->nudge_angle_incr);
+ b->nudge_angle_incr = NULL;
+ }
+ if (b->nudge_angle) {
+ (void) free((void *) b->nudge_angle);
+ b->nudge_angle = NULL;
+ }
+ if (b->contributions) {
+ (void) free((void *) b->contributions);
+ b->contributions = NULL;
+ }
+ (void) free((void *) b);
+ b = NULL;
+ }
+}
+
+/* Rotate and wobble a bubble by a single step. */
+void
+glb_bubble_step(void *bb)
+{
+ int i;
+ bubble *b = (bubble *) bb;
+
+ /* Update the rotation. */
+ b->rotx += b->rotx_incr;
+ b->roty += b->roty_incr;
+ b->rotz += b->rotz_incr;
+
+ /* Update the nudge angles. */
+ for (i = 0; i < glb_config.nr_nudge_axes; ++i)
+ b->nudge_angle[i] += b->nudge_angle_incr[i];
+
+ /* Move it upwards & outwards. */
+ b->y += b->y_incr;
+ b->scale += b->scale_incr;
+}
+
+/* Draw a bubble. */
+void
+glb_bubble_draw(void *bb)
+{
+ int i, j;
+ bubble *b = (bubble *) bb;
+ int nr_vertices;
+ glb_vertex *vertices = glb_sphere_get_vertices(&nr_vertices);
+ int nr_triangles;
+ glb_triangle *triangles = glb_sphere_get_triangles(&nr_triangles);
+ glb_vertex *new_vertices;
+
+ new_vertices = (glb_vertex *) malloc(sizeof (glb_vertex) * nr_vertices);
+ /* Calculate the vertices of this bubble, factoring in each nudge axis. */
+ for (i = 0; i < nr_vertices; ++i) {
+ GLfloat s = 0;
+
+ for (j = 0; j < glb_config.nr_nudge_axes; ++j)
+ s += ((GLfloat) cos((double) (b->nudge_angle[j])) *
+ glb_config.nudge_factor - glb_config.nudge_factor / 2) *
+ b->contributions[i * glb_config.nr_nudge_axes + j];
+
+ new_vertices[i][0] = vertices[i][0] * (s + 1);
+ new_vertices[i][1] = vertices[i][1] * (s + 1);
+ new_vertices[i][2] = vertices[i][2] * (s + 1);
+ }
+
+ glPushMatrix();
+
+ /* Apply translation, rotation and scalings. */
+ glTranslatef(b->x, b->y, b->z);
+
+ glRotatef(b->rotx, 1, 0, 0);
+ glRotatef(b->roty, 0, 1, 0);
+ glRotatef(b->rotz, 0, 0, 1);
+
+ glScalef(b->scale, b->scale, b->scale);
+
+ /* Draw the bubble. */
+ glBegin(GL_TRIANGLES);
+ for (i = 0; i < nr_triangles; ++i) {
+ glNormal3fv(new_vertices[triangles[i][0]]);
+ glVertex3fv(new_vertices[triangles[i][0]]);
+ glNormal3fv(new_vertices[triangles[i][1]]);
+ glVertex3fv(new_vertices[triangles[i][1]]);
+ glNormal3fv(new_vertices[triangles[i][2]]);
+ glVertex3fv(new_vertices[triangles[i][2]]);
+ }
+ glEnd();
+ glPopMatrix();
+ (void) free((void *) new_vertices);
+}
+
+/* Return y value. */
+GLfloat
+glb_bubble_get_y(void *bb)
+{
+ bubble *b = (bubble *) bb;
+
+ return b->y;
+}
projects / xscreensaver / blobdiff