2 static const char sccsid[] = "@(#)b_draw.c 4.11 98/06/16 xlockmore";
6 * BUBBLE3D (C) 1998 Richard W.M. Jones.
7 * b_draw.c: This code creates new bubbles, manages them and controls
8 * them as they are drawn on the screen.
13 typedef struct draw_context {
14 /* The list of bubbles currently on the screen. */
18 /* When was the last time we created a new bubble? */
30 GLfloat mat_specular[] =
32 GLfloat mat_emission[] =
34 GLfloat mat_shininess[] =
38 GLfloat light_position[][4] =
43 GLfloat light_diffuse[][4] =
48 GLfloat light_specular[][4] =
54 /* Initialize the context. */
55 c = (struct draw_context *) malloc(sizeof (struct draw_context));
61 c->bubble_count = glb_config.create_bubbles_every;
63 /* Do some GL initialization. */
64 glClearColor(glb_config.bg_colour[0],
65 glb_config.bg_colour[1],
66 glb_config.bg_colour[2],
67 glb_config.bg_colour[3]);
69 glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, glb_config.bubble_colour);
70 glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, mat_specular);
71 glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, mat_emission);
72 glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, mat_shininess);
74 if (glb_config.transparent_p)
75 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
77 glEnable(GL_LIGHTING);
82 if (glb_config.transparent_p)
85 glEnable(GL_DEPTH_TEST);
87 glEnable(GL_AUTO_NORMAL);
88 glEnable(GL_NORMALIZE);
90 if (glb_config.transparent_p)
91 glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
93 glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambient);
94 glLightfv(GL_LIGHT0, GL_POSITION, light_position[0]);
95 glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse[0]);
96 glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular[0]);
97 glLightfv(GL_LIGHT1, GL_POSITION, light_position[1]);
98 glLightfv(GL_LIGHT1, GL_DIFFUSE, light_diffuse[1]);
99 glLightfv(GL_LIGHT1, GL_SPECULAR, light_specular[1]);
100 glLightfv(GL_LIGHT2, GL_POSITION, light_position[2]);
101 glLightfv(GL_LIGHT2, GL_DIFFUSE, light_diffuse[2]);
102 glLightfv(GL_LIGHT2, GL_SPECULAR, light_specular[2]);
104 c->d = glb_sphere_init();
110 delete_bubble(draw_context * c, int j)
114 glb_bubble_delete(c->bubble_list[j]);
116 for (i = j; i < c->nr_bubbles - 1; ++i)
117 c->bubble_list[i] = c->bubble_list[i + 1];
123 glb_draw_end(void *cc)
125 draw_context *c = (draw_context *) cc;
128 for (i = 0; i < c->nr_bubbles; ++i) {
133 glb_sphere_end (c->d);
135 (void) free((void *) c->bubble_list);
136 (void) free((void *) c);
140 create_new_bubbles(draw_context * c)
143 double r = glb_drand();
144 GLfloat size, speed, scale_incr, x, y, z;
146 void **old_bubble_list;
148 /* How many bubbles to make? */
149 if (r < glb_config.p_bubble_group[0])
151 else if (r < glb_config.p_bubble_group[1])
153 else if (r < glb_config.p_bubble_group[2])
158 /* Initial position of top-most bubble in group. */
159 x = glb_drand() * 4 - 2;
160 y = glb_config.screen_bottom;
161 z = glb_drand() * 2 - 2;
164 size = glb_config.min_size
165 + glb_drand() * (glb_config.max_size - glb_config.min_size);
168 speed = glb_config.min_speed
169 + glb_drand() * (glb_config.max_speed - glb_config.min_speed);
171 /* Work out the scaling increment. Bubbles should increase by scale_factor
172 * as they go from bottom to top of screen.
174 scale_incr = (size * glb_config.scale_factor - size)
175 / ((glb_config.screen_top - glb_config.screen_bottom) / speed);
177 /* Create the bubble(s). */
178 for (i = 0; i < n; ++i) {
179 if ((b[i] = glb_bubble_new(c->d, x, y, z, size, speed, scale_incr)) == 0) {
180 /* Out of memory - recover. */
183 glb_bubble_delete(b[i]);
186 /* Create the next bubble below the last bubble. */
190 /* Add the bubbles to the list. */
192 old_bubble_list = c->bubble_list;
193 if (c->bubble_list == 0) {
194 c->bubble_list = (void **) malloc(c->nr_bubbles * sizeof (void *));
196 c->bubble_list = (void **) realloc(c->bubble_list,
197 c->nr_bubbles * sizeof (void *));
200 if (c->bubble_list == 0) {
201 /* Out of memory - recover. */
202 for (i = 0; i < n; ++i)
203 glb_bubble_delete(b[i]);
204 c->bubble_list = old_bubble_list;
208 for (i = 0; i < n; ++i)
209 c->bubble_list[c->nr_bubbles - i - 1] = b[i];
215 glb_draw_step(void *cc)
217 draw_context *c = (draw_context *) cc;
220 /* Consider creating a new bubble or bubbles. */
221 if (c->nr_bubbles < glb_config.max_bubbles &&
222 c->bubble_count++ > glb_config.create_bubbles_every) {
223 if (create_new_bubbles(c))
226 /* Clear the display. */
227 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
229 /* XXX Draw the background here ... */
231 /* Draw all the bubbles on the display. */
232 for (i = 0; i < c->nr_bubbles; ++i) {
233 void *b = c->bubble_list[i];
236 glb_bubble_draw(c->d, b);
238 /* Has the bubble reached the top of the screen? */
239 if (glb_bubble_get_y(b) >= glb_config.screen_top) {