libgender/oct.C

#include <cstdlib>

#include <vector>

using namespace std;

#define GL_GLEXT_PROTOTYPES
#include <GL/gl.h>

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

vector<GLuint> occ_query_objects;

static GLuint begin_occ_query ()
{
  GLuint id;

  if (occ_query_objects.size ())
    {
      id = *(occ_query_objects.end () - 1);
      occ_query_objects.pop_back ();
    }
  else
    glGenQueries (1, &id);

  glBeginQuery (GL_SAMPLES_PASSED, id);
  return id;
}

#define end_occ_query() glEndQuery (GL_SAMPLES_PASSED);

static GLuint occ_query_result (GLuint id)
{
  GLuint count;

  glGetQueryObjectuiv (id, GL_QUERY_RESULT, &count);
  occ_query_objects.push_back (id);

  return count;
}

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

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

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

static bool overlap (const sector &o1, uoffs ea, const box &bbox)
{
  sector a2, b2;

  ea /= 2;

  a2.x = o1.x + ea;
  a2.y = o1.y + ea;
  a2.z = o1.z + ea;
  
  b2.x = (bbox.a.x + bbox.b.x) / 2;
  b2.y = (bbox.a.y + bbox.b.y) / 2;
  b2.z = (bbox.a.z + bbox.b.z) / 2;

  return abs (a2.x - b2.x) <= ea + (bbox.b.x - bbox.a.x)
      && abs (a2.y - b2.y) <= ea + (bbox.b.y - bbox.a.y)
      && abs (a2.z - b2.z) <= ea + (bbox.b.z - bbox.a.z);
}

void octant::add (entity_base *e)
{
  box bbox = translate (e->bbox, e->orig, sector (0, 0, 0));

  uoffs size = max (abs (bbox.b.x - bbox.a.x),
               max (abs (bbox.b.y - bbox.a.y),
                    abs (bbox.b.z - bbox.a.z)));

  if (overlap (orig, extent, bbox))
    {
      uoffs extent2 = extent / 2;

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

      for (int i = 8; i--; )
        {
          sector s = orig;
          s.offset (i, extent2);
          if (overlap (s, extent2, bbox))
            {
              if (!sub[i])
                sub[i] = new octant (this, s, extent2);

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

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

void octant::detect_visibility (view &ctx)
{
  visibility_state &vs = ctx.vismap[this];

  if (vs.generation != ctx.generation)
    vs.visibility = visibility_state::UNKNOWN;

  const sector &cam = ctx.orig;
  if (cam.x >= orig.x && cam.x <= orig.x + extent
      && cam.y >= orig.y && cam.y <= orig.y + extent
      && cam.z >= orig.z && cam.z <= orig.z + extent)
    {
      vs.visibility = visibility_state::PARTIAL;
      vs.generation = ctx.generation;
    }
  else
    {
      point center (
        orig.x + (soffs)extent / 2 - cam.x,
        orig.y + (soffs)extent / 2 - cam.y,
        orig.z + (soffs)extent / 2 - cam.z 
      );

      GLfloat dia = (0.5 * sqrtf (3))*(GLfloat)extent;

      if (ctx.frustum.t.distance (center) < -dia) return;
      if (ctx.frustum.b.distance (center) < -dia) return;
      if (ctx.frustum.l.distance (center) < -dia) return;
      if (ctx.frustum.r.distance (center) < -dia) return;
      if (ctx.frustum.n.distance (center) < -dia) return;
      if (ctx.frustum.f.distance (center) < -dia) return;
    }

  if (size ())
    ctx.vislist.push_back (this);

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

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

  for (int i = 0; i < 8; i++)
    {
      si ^= next[i];

      if (sub[si])
        sub[si]->detect_visibility (ctx);
    }

  vs.generation = ctx.generation;
}

void octant::display (view &ctx)
{
#if 0
  glBegin (GL_LINES);
  sector s = orig;
  s.x -= ctx.orig.x;
  s.y -= ctx.orig.y;
  s.z -= ctx.orig.z;
  vec3 clr(0, 0.8, 0);
  glMaterialfv (GL_FRONT_AND_BACK, GL_DIFFUSE, (const GLfloat*)&clr);

  for (int i = 8; i--; )
    for (int ji = 3; ji--; )
      {
        int j = i | (1 << ji);
        if (i != j)
          {
            glVertex3i (s.x + !!(i & 1) * extent,
                        s.y + !!(i & 2) * extent,
                        s.z + !!(i & 4) * extent);
            glVertex3i (s.x + !!(j & 1) * extent,
                        s.y + !!(j & 2) * extent,
                        s.z + !!(j & 4) * extent);
          }
      }
  
  glEnd ();
  glDisable(GL_COLOR_MATERIAL);
#endif

  for (iterator i = end (); i != begin (); )
    (*--i)->display (ctx);
}


Revision:	1.19
Committed:	Wed Oct 6 00:55:37 2004 UTC (19 years, 8 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.18:	+32 -45 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#include <cstdlib>
2
3	root	1.8	#include <vector>
4
5			using namespace std;
6
7			#define GL_GLEXT_PROTOTYPES
8			#include <GL/gl.h>
9
10	root	1.1	#include "oct.h"
11	root	1.8	#include "view.h"
12	root	1.2	#include "entity.h"
13
14	root	1.8	vector<GLuint> occ_query_objects;
15	root	1.2
16	root	1.8	static GLuint begin_occ_query ()
17	root	1.2	{
18	root	1.8	GLuint id;
19	root	1.2
20	root	1.8	if (occ_query_objects.size ())
21	root	1.3	{
22	root	1.8	id = *(occ_query_objects.end () - 1);
23			occ_query_objects.pop_back ();
24	root	1.3	}
25			else
26	root	1.11	glGenQueries (1, &id);
27	root	1.8
28	root	1.11	glBeginQuery (GL_SAMPLES_PASSED, id);
29	root	1.8	return id;
30			}
31
32	root	1.11	#define end_occ_query() glEndQuery (GL_SAMPLES_PASSED);
33	root	1.8
34			static GLuint occ_query_result (GLuint id)
35			{
36			GLuint count;
37
38	root	1.11	glGetQueryObjectuiv (id, GL_QUERY_RESULT, &count);
39	root	1.8	occ_query_objects.push_back (id);
40
41			return count;
42			}
43
44			octant world(0, sector (SOFFS_MIN, SOFFS_MIN, SOFFS_MIN), MAXEXTENT);
45
46			octant::octant (octant *parent, const sector &orig, uoffs extent)
47			: parent(parent), orig(orig), extent(extent)
48			{
49			for (fill = 8; fill--; )
50			sub[fill] = 0;
51	root	1.2	}
52
53			octant::~octant ()
54			{
55			for (fill = 8; fill--; )
56			delete sub[fill];
57			}
58
59	root	1.8	static bool overlap (const sector &o1, uoffs ea, const box &bbox)
60	root	1.4	{
61	root	1.8	sector a2, b2;
62	root	1.4
63			ea /= 2;
64
65			a2.x = o1.x + ea;
66			a2.y = o1.y + ea;
67			a2.z = o1.z + ea;
68
69	root	1.8	b2.x = (bbox.a.x + bbox.b.x) / 2;
70			b2.y = (bbox.a.y + bbox.b.y) / 2;
71			b2.z = (bbox.a.z + bbox.b.z) / 2;
72
73			return abs (a2.x - b2.x) <= ea + (bbox.b.x - bbox.a.x)
74			&& abs (a2.y - b2.y) <= ea + (bbox.b.y - bbox.a.y)
75			&& abs (a2.z - b2.z) <= ea + (bbox.b.z - bbox.a.z);
76	root	1.4	}
77
78	root	1.6	void octant::add (entity_base *e)
79	root	1.2	{
80	root	1.8	box bbox = translate (e->bbox, e->orig, sector (0, 0, 0));
81	root	1.7
82			uoffs size = max (abs (bbox.b.x - bbox.a.x),
83	root	1.8	max (abs (bbox.b.y - bbox.a.y),
84			abs (bbox.b.z - bbox.a.z)));
85	root	1.3
86	root	1.8	if (overlap (orig, extent, bbox))
87	root	1.4	{
88	root	1.8	uoffs extent2 = extent / 2;
89
90			if (size > extent2 \|\| !extent2)
91			{
92			push_back (e);
93			e->o.push_back (this);
94			return;
95			}
96	root	1.5
97	root	1.8	for (int i = 8; i--; )
98	root	1.5	{
99	root	1.8	sector s = orig;
100			s.offset (i, extent2);
101			if (overlap (s, extent2, bbox))
102	root	1.5	{
103	root	1.8	if (!sub[i])
104			sub[i] = new octant (this, s, extent2);
105
106			sub[i]->add (e);
107	root	1.5	}
108	root	1.8	}
109	root	1.4	}
110	root	1.2	}
111	root	1.1
112			void octant::remove (entity_base *e)
113			{
114			}
115
116	root	1.19	void octant::detect_visibility (view &ctx)
117	root	1.1	{
118	root	1.8	visibility_state &vs = ctx.vismap[this];
119
120			if (vs.generation != ctx.generation)
121	root	1.10	vs.visibility = visibility_state::UNKNOWN;
122
123	root	1.19	const sector &cam = ctx.orig;
124	root	1.10	if (cam.x >= orig.x && cam.x <= orig.x + extent
125			&& cam.y >= orig.y && cam.y <= orig.y + extent
126			&& cam.z >= orig.z && cam.z <= orig.z + extent)
127			{
128			vs.visibility = visibility_state::PARTIAL;
129			vs.generation = ctx.generation;
130			}
131			else
132			{
133			point center (
134	root	1.18	orig.x + (soffs)extent / 2 - cam.x,
135			orig.y + (soffs)extent / 2 - cam.y,
136	root	1.14	orig.z + (soffs)extent / 2 - cam.z
137	root	1.10	);
138
139	root	1.14	GLfloat dia = (0.5 * sqrtf (3))*(GLfloat)extent;
140
141			if (ctx.frustum.t.distance (center) < -dia) return;
142			if (ctx.frustum.b.distance (center) < -dia) return;
143			if (ctx.frustum.l.distance (center) < -dia) return;
144			if (ctx.frustum.r.distance (center) < -dia) return;
145			if (ctx.frustum.n.distance (center) < -dia) return;
146			if (ctx.frustum.f.distance (center) < -dia) return;
147	root	1.10	}
148	root	1.8
149	root	1.19	if (size ())
150			ctx.vislist.push_back (this);
151
152			// node to start with
153			unsigned char si = ctx.d.x < 0 ? 1 : 0
154			\| ctx.d.y < 0 ? 2 : 0
155			\| ctx.d.z < 0 ? 4 : 0;
156
157			// bit-toggle to find next child for front-to-back order
158			static unsigned char next[8]
159			= { 0, 0^1, 1^2, 2^4, 4^3, 3^5, 5^6, 6^7 };
160
161			for (int i = 0; i < 8; i++)
162			{
163			si ^= next[i];
164
165			if (sub[si])
166			sub[si]->detect_visibility (ctx);
167			}
168
169			vs.generation = ctx.generation;
170			}
171
172			void octant::display (view &ctx)
173			{
174	root	1.17	#if 0
175	root	1.8	glBegin (GL_LINES);
176			sector s = orig;
177	root	1.19	s.x -= ctx.orig.x;
178			s.y -= ctx.orig.y;
179			s.z -= ctx.orig.z;
180	root	1.13	vec3 clr(0, 0.8, 0);
181			glMaterialfv (GL_FRONT_AND_BACK, GL_DIFFUSE, (const GLfloat*)&clr);
182	root	1.8
183			for (int i = 8; i--; )
184			for (int ji = 3; ji--; )
185			{
186			int j = i \| (1 << ji);
187			if (i != j)
188			{
189			glVertex3i (s.x + !!(i & 1) * extent,
190			s.y + !!(i & 2) * extent,
191			s.z + !!(i & 4) * extent);
192			glVertex3i (s.x + !!(j & 1) * extent,
193			s.y + !!(j & 2) * extent,
194			s.z + !!(j & 4) * extent);
195			}
196			}
197
198			glEnd ();
199	root	1.13	glDisable(GL_COLOR_MATERIAL);
200	root	1.8	#endif
201
202	root	1.19	for (iterator i = end (); i != begin (); )
203			(*--i)->display (ctx);
204	root	1.1	}
205	root	1.8
206
207	root	1.2