2 Copyright (C) 2003, 2010 - Wolfire Games
4 This file is part of Lugaru.
6 Lugaru is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 Lugaru is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with Lugaru. If not, see <http://www.gnu.org/licenses/>.
29 static float projmatrix[16];
30 static float mvmatrix[16];
31 static float clip[16];
33 glGetFloatv(GL_PROJECTION_MATRIX, projmatrix);
34 glGetFloatv(GL_MODELVIEW_MATRIX, mvmatrix);
36 // Combine the matrices
37 clip[0] = mvmatrix[0] * projmatrix[0] + mvmatrix[1] * projmatrix[4] + mvmatrix[2] * projmatrix[8] + mvmatrix[3] * projmatrix[12];
38 clip[1] = mvmatrix[0] * projmatrix[1] + mvmatrix[1] * projmatrix[5] + mvmatrix[2] * projmatrix[9] + mvmatrix[3] * projmatrix[13];
39 clip[2] = mvmatrix[0] * projmatrix[2] + mvmatrix[1] * projmatrix[6] + mvmatrix[2] * projmatrix[10] + mvmatrix[3] * projmatrix[14];
40 clip[3] = mvmatrix[0] * projmatrix[3] + mvmatrix[1] * projmatrix[7] + mvmatrix[2] * projmatrix[11] + mvmatrix[3] * projmatrix[15];
42 clip[4] = mvmatrix[4] * projmatrix[0] + mvmatrix[5] * projmatrix[4] + mvmatrix[6] * projmatrix[8] + mvmatrix[7] * projmatrix[12];
43 clip[5] = mvmatrix[4] * projmatrix[1] + mvmatrix[5] * projmatrix[5] + mvmatrix[6] * projmatrix[9] + mvmatrix[7] * projmatrix[13];
44 clip[6] = mvmatrix[4] * projmatrix[2] + mvmatrix[5] * projmatrix[6] + mvmatrix[6] * projmatrix[10] + mvmatrix[7] * projmatrix[14];
45 clip[7] = mvmatrix[4] * projmatrix[3] + mvmatrix[5] * projmatrix[7] + mvmatrix[6] * projmatrix[11] + mvmatrix[7] * projmatrix[15];
47 clip[8] = mvmatrix[8] * projmatrix[0] + mvmatrix[9] * projmatrix[4] + mvmatrix[10] * projmatrix[8] + mvmatrix[11] * projmatrix[12];
48 clip[9] = mvmatrix[8] * projmatrix[1] + mvmatrix[9] * projmatrix[5] + mvmatrix[10] * projmatrix[9] + mvmatrix[11] * projmatrix[13];
49 clip[10] = mvmatrix[8] * projmatrix[2] + mvmatrix[9] * projmatrix[6] + mvmatrix[10] * projmatrix[10] + mvmatrix[11] * projmatrix[14];
50 clip[11] = mvmatrix[8] * projmatrix[3] + mvmatrix[9] * projmatrix[7] + mvmatrix[10] * projmatrix[11] + mvmatrix[11] * projmatrix[15];
52 clip[12] = mvmatrix[12] * projmatrix[0] + mvmatrix[13] * projmatrix[4] + mvmatrix[14] * projmatrix[8] + mvmatrix[15] * projmatrix[12];
53 clip[13] = mvmatrix[12] * projmatrix[1] + mvmatrix[13] * projmatrix[5] + mvmatrix[14] * projmatrix[9] + mvmatrix[15] * projmatrix[13];
54 clip[14] = mvmatrix[12] * projmatrix[2] + mvmatrix[13] * projmatrix[6] + mvmatrix[14] * projmatrix[10] + mvmatrix[15] * projmatrix[14];
55 clip[15] = mvmatrix[12] * projmatrix[3] + mvmatrix[13] * projmatrix[7] + mvmatrix[14] * projmatrix[11] + mvmatrix[15] * projmatrix[15];
58 frustum[0][0] = clip[3] - clip[0];
59 frustum[0][1] = clip[7] - clip[4];
60 frustum[0][2] = clip[11] - clip[8];
61 frustum[0][3] = clip[15] - clip[12];
64 frustum[1][0] = clip[3] + clip[0];
65 frustum[1][1] = clip[7] + clip[4];
66 frustum[1][2] = clip[11] + clip[8];
67 frustum[1][3] = clip[15] + clip[12];
70 frustum[2][0] = clip[3] + clip[1];
71 frustum[2][1] = clip[7] + clip[5];
72 frustum[2][2] = clip[11] + clip[9];
73 frustum[2][3] = clip[15] + clip[13];
76 frustum[3][0] = clip[3] - clip[1];
77 frustum[3][1] = clip[7] - clip[5];
78 frustum[3][2] = clip[11] - clip[9];
79 frustum[3][3] = clip[15] - clip[13];
82 frustum[4][0] = clip[3] - clip[2];
83 frustum[4][1] = clip[7] - clip[6];
84 frustum[4][2] = clip[11] - clip[10];
85 frustum[4][3] = clip[15] - clip[14];
88 frustum[5][0] = clip[3] + clip[2];
89 frustum[5][1] = clip[7] + clip[6];
90 frustum[5][2] = clip[11] + clip[10];
91 frustum[5][3] = clip[15] + clip[14];
95 CubeInFrustum(float x, float y, float z, float size)
99 for (int i = 0; i < 6; i++) {
101 if (frustum[i][0] * (x - size) + frustum[i][1] * (y - size) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
103 if (frustum[i][0] * (x + size) + frustum[i][1] * (y - size) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
105 if (frustum[i][0] * (x - size) + frustum[i][1] * (y + size) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
107 if (frustum[i][0] * (x + size) + frustum[i][1] * (y + size) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
109 if (frustum[i][0] * (x - size) + frustum[i][1] * (y - size) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
111 if (frustum[i][0] * (x + size) + frustum[i][1] * (y - size) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
113 if (frustum[i][0] * (x - size) + frustum[i][1] * (y + size) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
115 if (frustum[i][0] * (x + size) + frustum[i][1] * (y + size) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
129 CubeInFrustum(float x, float y, float z, float size, float height)
133 for (int i = 0; i < 6; i++) {
135 if (frustum[i][0] * (x - size) + frustum[i][1] * (y - height) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
137 if (frustum[i][0] * (x + size) + frustum[i][1] * (y - height) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
139 if (frustum[i][0] * (x - size) + frustum[i][1] * (y + height) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
141 if (frustum[i][0] * (x + size) + frustum[i][1] * (y + height) + frustum[i][2] * (z - size) + frustum[i][3] > 0)
143 if (frustum[i][0] * (x - size) + frustum[i][1] * (y - height) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
145 if (frustum[i][0] * (x + size) + frustum[i][1] * (y - height) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
147 if (frustum[i][0] * (x - size) + frustum[i][1] * (y + height) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
149 if (frustum[i][0] * (x + size) + frustum[i][1] * (y + height) + frustum[i][2] * (z + size) + frustum[i][3] > 0)
163 SphereInFrustum(float x, float y, float z, float radius)
167 for (int i = 0; i < 6; i++) {
168 if (frustum[i][0] * x + frustum[i][1] * y + frustum[i][2] * z + frustum[i][3] > -1 * radius)