libgender/oct.C

#include <cstdlib>

#include <vector>
using namespace std;

#include "opengl.h"

#include "oct.h"
#include "view.h"
#include "entity.h"

enum visibility_state { FULL, PARTIAL, SMALL, OCCLUDED, SUBTREE_OCCLUDED };

struct evis {
  visibility_state state;
  double last; // time of last check
  evis () : last(0.), state(FULL) { };
};

struct oct_visibility : visibility_base
{
  typedef map<entity *, evis> evismap;
  evismap vismap;

  visibility_state state;

  oct_visibility (octant &oct)
  : state(FULL)
  {
  }
};

octant world(0, sector (0, 0, 0), MAXEXTENT);

octant::octant (octant *parent, const sector &orig, uoffs extent)
: parent(parent)
, orig(orig)
, extent(extent)
{
  for (fill = 8; fill--; )
    sub[fill] = 0;
}

visibility_base *octant::new_visibility ()
{
  return new oct_visibility (*this);
}

void octant::clear_visibility (visibility_base *vs)
{
  ((oct_visibility *)vs)->vismap.clear ();
  ((oct_visibility *)vs)->state = FULL;
}

octant::~octant ()
{
  for (fill = 8; fill--; )
    delete sub[fill];
}

static bool overlap (const sector &orig, uoffs extent, const sector &a, const sector &b)
{
  sector size   = (b - a + 1) >> 1;
  sector center = a + size;

  return abs (orig - center) <= extent + size;
}

static sector offset (const sector &s, int subindex, uoffs extent)
{
  return sector (
    s.x + (subindex & 1 ? extent : -extent),
    s.y + (subindex & 2 ? extent : -extent),
    s.z + (subindex & 4 ? extent : -extent)
  );
}

void octant::add (entity *e)
{
  const sector &a = e->a;
  const sector &b = e->b;

  if (overlap (orig, extent, a, b))
    {
      uoffs extent2 = extent >> 1;
      uoffs size = max (abs (b - a));

      if (size >= extent2)
        {
          push_back (e);
          e->o.push_back (this);
          return;
        }

      for (int i = 8; i--; )
        {
          sector s = offset (orig, i, extent2);

          if (overlap (s, extent2, a, b))
            {
              if (!sub[i])
                {
                  sub[i] = new octant (this, s, extent2);
                  fill++;
                }

              sub[i]->add (e);
            }
        }
    }
}

void octant::remove (entity *e)
{
}

bool octant::detect_visibility (view &ctx)
{
  ctx.stat1++;//D

  sector centeri = orig - ctx.orig;
  point centerf = point (centeri);

  GLfloat rad = ctx.diagfact * extent;

  if (!overlap (ctx.frustum.c, sphere (centerf, rad)))
    return false;

  oct_visibility &vs = *(oct_visibility *)get_visibility (ctx);

  if (max (abs (centeri)) <= extent)
    vs.state = PARTIAL;
  else
    {
      if (distance (ctx.frustum.t, centerf) < -rad) return false;
      if (distance (ctx.frustum.b, centerf) < -rad) return false;
      if (distance (ctx.frustum.l, centerf) < -rad) return false;
      if (distance (ctx.frustum.r, centerf) < -rad) return false;
      if (distance (ctx.frustum.n, centerf) < -rad) return false;

#if 0
      GLfloat fd = distance (ctx.frustum.f, centerf);

      if (fd < -(ctx.c_far - ctx.z_far) -rad * 3.F)
        return false;
#endif
    }

  // very important, optimize?
  GLfloat z = ctx.z_near + distance (ctx.frustum.n, centerf) + rad;
  if (ctx.perspfact * extent / z < 1.) // very crude "too small to see" check
    return false;

#if 0
  if (vs.state == PARTIAL || vs.state == FULL)
    ctx.nc_far = max (ctx.nc_far, z);
#endif

  if (vs.state == SUBTREE_OCCLUDED)
    {
      ctx.vislist.push_back (this);
      return false;
    }
 
  bool visible = size () && (vs.state == PARTIAL || vs.state == FULL);

  // node to start with
  unsigned char si = centeri.x > 0 ? 1 : 0
                   | centeri.y > 0 ? 2 : 0
                   | centeri.z > 0 ? 4 : 0;

  // bit-toggle to find next child for front-to-back order
  static unsigned char toggle[8+1]
    = { 0,  0^1, 1^2, 2^4, 4^3, 3^5, 5^6,  6^7, 0 };

  unsigned char *next = toggle;
  do
    {
      si ^= *next;

      if (sub[si])
        visible = visible | sub[si]->detect_visibility (ctx);
    }
  while (*++next);

  if (visible)
    {
      if (size ())
        ctx.vislist.push_back (this);
    }
  else
    vs.state = SUBTREE_OCCLUDED;

  return visible;
}

void octant::draw_depth (view &ctx)
{
  oct_visibility &vs = *(oct_visibility *)get_visibility (ctx);

  if (vs.state == OCCLUDED || vs.state == SUBTREE_OCCLUDED)
    return;

  for (iterator i = begin (); i != end (); )
    {
      entity *e = *i++;

      evis &evs = vs.vismap[e];

      if (evs.state != OCCLUDED)
        {
          if (!ctx.may_draw (e))
            continue;

          sector center = ((e->a + e->b) >> 1) - ctx.orig;
          GLfloat z = length (vec3 (center));
          ctx.pixfact = ctx.perspfact / z;

          ctx.nz_far  = max (ctx.nz_far,  z + extent);
          ctx.nz_near = min (ctx.nz_near, z - extent);

          e->draw (ctx);
        }
    }
}

void octant::draw_postdepth (view &ctx)
{
  oct_visibility &vs = *(oct_visibility *)get_visibility (ctx);

  if (vs.state == OCCLUDED || vs.state == SUBTREE_OCCLUDED)
    {
      ctx.begin_occ_query (*this, 0);
      sector s = orig - ctx.orig;
      gl::draw_bbox (s - extent, s + extent);
      ctx.end_occ_query ();
    }
  else
    {
      int nvis = 0;

      for (iterator i = begin (); i != end (); )
        {
          entity *e = *i++;

          evis &evs = vs.vismap[e];

          if (evs.state == OCCLUDED)
            {
              if (!ctx.may_draw (e))
                continue;

              ctx.begin_occ_query (*this, e);
              gl::draw_bbox (e->a - ctx.orig, e->b - ctx.orig);
              ctx.end_occ_query ();
            }
          else
            nvis++;
        }

      if (nvis == 0 && size ())
        vs.state = OCCLUDED;
    }
}

void octant::draw_lighted (view &ctx)
{
  oct_visibility &vs = *(oct_visibility *)get_visibility (ctx);

  if (vs.state == OCCLUDED || vs.state == SUBTREE_OCCLUDED)
    return;

  for (iterator i = begin (); i != end (); )
    {
      entity *e = *i++;

      evis &evs = vs.vismap[e];

      if (evs.state != OCCLUDED)
        {
          if (!ctx.may_draw (e))
            continue;

          sector center = ((e->a + e->b) >> 1) - ctx.orig;
          GLfloat z = length (vec3 (center));
          ctx.pixfact = ctx.perspfact / z;

          if (ctx.pass->type != LIGHTED 
              || !ctx.first_lighted
              || evs.last + 0.1 > timer.now)
            e->draw (ctx);
          else
            {
              evs.last = timer.now;
              ctx.begin_occ_query (*this, e);
              e->draw (ctx);
              ctx.end_occ_query ();
            }
        }
    }
}

void octant::event (occ_query &ev)
{
  oct_visibility &vs = *(oct_visibility *)get_visibility (ev.ctx);
  entity *e = (entity *)ev.id;

  if (e)
    {
      evis &evs = vs.vismap[e];
      evs.state = ev.count ? FULL : OCCLUDED;
    }
  else
    vs.state = ev.count ? FULL : OCCLUDED;
}


Revision:	1.78
Committed:	Wed Nov 10 01:57:15 2004 UTC (19 years, 7 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.77:	+1 -4 lines
Log Message:	* empty log message *
#	Content
1	#include <cstdlib>
2
3	#include <vector>
4	using namespace std;
5
6	#include "opengl.h"
7
8	#include "oct.h"
9	#include "view.h"
10	#include "entity.h"
11
12	enum visibility_state { FULL, PARTIAL, SMALL, OCCLUDED, SUBTREE_OCCLUDED };
13
14	struct evis {
15	visibility_state state;
16	double last; // time of last check
17	evis () : last(0.), state(FULL) { };
18	};
19
20	struct oct_visibility : visibility_base
21	{
22	typedef map<entity *, evis> evismap;
23	evismap vismap;
24
25	visibility_state state;
26
27	oct_visibility (octant &oct)
28	: state(FULL)
29	{
30	}
31	};
32
33	octant world(0, sector (0, 0, 0), MAXEXTENT);
34
35	octant::octant (octant *parent, const sector &orig, uoffs extent)
36	: parent(parent)
37	, orig(orig)
38	, extent(extent)
39	{
40	for (fill = 8; fill--; )
41	sub[fill] = 0;
42	}
43
44	visibility_base *octant::new_visibility ()
45	{
46	return new oct_visibility (*this);
47	}
48
49	void octant::clear_visibility (visibility_base *vs)
50	{
51	((oct_visibility *)vs)->vismap.clear ();
52	((oct_visibility *)vs)->state = FULL;
53	}
54
55	octant::~octant ()
56	{
57	for (fill = 8; fill--; )
58	delete sub[fill];
59	}
60
61	static bool overlap (const sector &orig, uoffs extent, const sector &a, const sector &b)
62	{
63	sector size = (b - a + 1) >> 1;
64	sector center = a + size;
65
66	return abs (orig - center) <= extent + size;
67	}
68
69	static sector offset (const sector &s, int subindex, uoffs extent)
70	{
71	return sector (
72	s.x + (subindex & 1 ? extent : -extent),
73	s.y + (subindex & 2 ? extent : -extent),
74	s.z + (subindex & 4 ? extent : -extent)
75	);
76	}
77
78	void octant::add (entity *e)
79	{
80	const sector &a = e->a;
81	const sector &b = e->b;
82
83	if (overlap (orig, extent, a, b))
84	{
85	uoffs extent2 = extent >> 1;
86	uoffs size = max (abs (b - a));
87
88	if (size >= extent2)
89	{
90	push_back (e);
91	e->o.push_back (this);
92	return;
93	}
94
95	for (int i = 8; i--; )
96	{
97	sector s = offset (orig, i, extent2);
98
99	if (overlap (s, extent2, a, b))
100	{
101	if (!sub[i])
102	{
103	sub[i] = new octant (this, s, extent2);
104	fill++;
105	}
106
107	sub[i]->add (e);
108	}
109	}
110	}
111	}
112
113	void octant::remove (entity *e)
114	{
115	}
116
117	bool octant::detect_visibility (view &ctx)
118	{
119	ctx.stat1++;//D
120
121	sector centeri = orig - ctx.orig;
122	point centerf = point (centeri);
123
124	GLfloat rad = ctx.diagfact * extent;
125
126	if (!overlap (ctx.frustum.c, sphere (centerf, rad)))
127	return false;
128
129	oct_visibility &vs = (oct_visibility )get_visibility (ctx);
130
131	if (max (abs (centeri)) <= extent)
132	vs.state = PARTIAL;
133	else
134	{
135	if (distance (ctx.frustum.t, centerf) < -rad) return false;
136	if (distance (ctx.frustum.b, centerf) < -rad) return false;
137	if (distance (ctx.frustum.l, centerf) < -rad) return false;
138	if (distance (ctx.frustum.r, centerf) < -rad) return false;
139	if (distance (ctx.frustum.n, centerf) < -rad) return false;
140
141	#if 0
142	GLfloat fd = distance (ctx.frustum.f, centerf);
143
144	if (fd < -(ctx.c_far - ctx.z_far) -rad * 3.F)
145	return false;
146	#endif
147	}
148
149	// very important, optimize?
150	GLfloat z = ctx.z_near + distance (ctx.frustum.n, centerf) + rad;
151	if (ctx.perspfact * extent / z < 1.) // very crude "too small to see" check
152	return false;
153
154	#if 0
155	if (vs.state == PARTIAL \|\| vs.state == FULL)
156	ctx.nc_far = max (ctx.nc_far, z);
157	#endif
158
159	if (vs.state == SUBTREE_OCCLUDED)
160	{
161	ctx.vislist.push_back (this);
162	return false;
163	}
164
165	bool visible = size () && (vs.state == PARTIAL \|\| vs.state == FULL);
166
167	// node to start with
168	unsigned char si = centeri.x > 0 ? 1 : 0
169	\| centeri.y > 0 ? 2 : 0
170	\| centeri.z > 0 ? 4 : 0;
171
172	// bit-toggle to find next child for front-to-back order
173	static unsigned char toggle[8+1]
174	= { 0, 0^1, 1^2, 2^4, 4^3, 3^5, 5^6, 6^7, 0 };
175
176	unsigned char *next = toggle;
177	do
178	{
179	si ^= *next;
180
181	if (sub[si])
182	visible = visible \| sub[si]->detect_visibility (ctx);
183	}
184	while (*++next);
185
186	if (visible)
187	{
188	if (size ())
189	ctx.vislist.push_back (this);
190	}
191	else
192	vs.state = SUBTREE_OCCLUDED;
193
194	return visible;
195	}
196
197	void octant::draw_depth (view &ctx)
198	{
199	oct_visibility &vs = (oct_visibility )get_visibility (ctx);
200
201	if (vs.state == OCCLUDED \|\| vs.state == SUBTREE_OCCLUDED)
202	return;
203
204	for (iterator i = begin (); i != end (); )
205	{
206	entity e = i++;
207
208	evis &evs = vs.vismap[e];
209
210	if (evs.state != OCCLUDED)
211	{
212	if (!ctx.may_draw (e))
213	continue;
214
215	sector center = ((e->a + e->b) >> 1) - ctx.orig;
216	GLfloat z = length (vec3 (center));
217	ctx.pixfact = ctx.perspfact / z;
218
219	ctx.nz_far = max (ctx.nz_far, z + extent);
220	ctx.nz_near = min (ctx.nz_near, z - extent);
221
222	e->draw (ctx);
223	}
224	}
225	}
226
227	void octant::draw_postdepth (view &ctx)
228	{
229	oct_visibility &vs = (oct_visibility )get_visibility (ctx);
230
231	if (vs.state == OCCLUDED \|\| vs.state == SUBTREE_OCCLUDED)
232	{
233	ctx.begin_occ_query (*this, 0);
234	sector s = orig - ctx.orig;
235	gl::draw_bbox (s - extent, s + extent);
236	ctx.end_occ_query ();
237	}
238	else
239	{
240	int nvis = 0;
241
242	for (iterator i = begin (); i != end (); )
243	{
244	entity e = i++;
245
246	evis &evs = vs.vismap[e];
247
248	if (evs.state == OCCLUDED)
249	{
250	if (!ctx.may_draw (e))
251	continue;
252
253	ctx.begin_occ_query (*this, e);
254	gl::draw_bbox (e->a - ctx.orig, e->b - ctx.orig);
255	ctx.end_occ_query ();
256	}
257	else
258	nvis++;
259	}
260
261	if (nvis == 0 && size ())
262	vs.state = OCCLUDED;
263	}
264	}
265
266	void octant::draw_lighted (view &ctx)
267	{
268	oct_visibility &vs = (oct_visibility )get_visibility (ctx);
269
270	if (vs.state == OCCLUDED \|\| vs.state == SUBTREE_OCCLUDED)
271	return;
272
273	for (iterator i = begin (); i != end (); )
274	{
275	entity e = i++;
276
277	evis &evs = vs.vismap[e];
278
279	if (evs.state != OCCLUDED)
280	{
281	if (!ctx.may_draw (e))
282	continue;
283
284	sector center = ((e->a + e->b) >> 1) - ctx.orig;
285	GLfloat z = length (vec3 (center));
286	ctx.pixfact = ctx.perspfact / z;
287
288	if (ctx.pass->type != LIGHTED
289	\|\| !ctx.first_lighted
290	\|\| evs.last + 0.1 > timer.now)
291	e->draw (ctx);
292	else
293	{
294	evs.last = timer.now;
295	ctx.begin_occ_query (*this, e);
296	e->draw (ctx);
297	ctx.end_occ_query ();
298	}
299	}
300	}
301	}
302
303	void octant::event (occ_query &ev)
304	{
305	oct_visibility &vs = (oct_visibility )get_visibility (ev.ctx);
306	entity e = (entity )ev.id;
307
308	if (e)
309	{
310	evis &evs = vs.vismap[e];
311	evs.state = ev.count ? FULL : OCCLUDED;
312	}
313	else
314	vs.state = ev.count ? FULL : OCCLUDED;
315	}
316
317