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Diffstat (limited to 'src/Frustum.cpp')
| -rw-r--r-- | src/Frustum.cpp | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/src/Frustum.cpp b/src/Frustum.cpp new file mode 100644 index 0000000..0e617b8 --- /dev/null +++ b/src/Frustum.cpp @@ -0,0 +1,246 @@ +#include <cmath> +#ifdef OS9 +#include "gl.h" +#else +#include <GL/gl.h> +#endif + +#include "Frustum.h" + +void FRUSTUM:: + GetFrustum() { + float projmatrix[16]; + float mvmatrix[16]; + float clip[16]; + float t; + + glGetFloatv(GL_PROJECTION_MATRIX, projmatrix); + glGetFloatv(GL_MODELVIEW_MATRIX, mvmatrix); + + // Combine the matrices + clip[0] = mvmatrix[0] * projmatrix[0] + mvmatrix[1] * projmatrix[4] + mvmatrix[2] * projmatrix[8] + mvmatrix[3] * projmatrix[12]; + clip[1] = mvmatrix[0] * projmatrix[1] + mvmatrix[1] * projmatrix[5] + mvmatrix[2] * projmatrix[9] + mvmatrix[3] * projmatrix[13]; + clip[2] = mvmatrix[0] * projmatrix[2] + mvmatrix[1] * projmatrix[6] + mvmatrix[2] * projmatrix[10] + mvmatrix[3] * projmatrix[14]; + clip[3] = mvmatrix[0] * projmatrix[3] + mvmatrix[1] * projmatrix[7] + mvmatrix[2] * projmatrix[11] + mvmatrix[3] * projmatrix[15]; + + clip[4] = mvmatrix[4] * projmatrix[0] + mvmatrix[5] * projmatrix[4] + mvmatrix[6] * projmatrix[8] + mvmatrix[7] * projmatrix[12]; + clip[5] = mvmatrix[4] * projmatrix[1] + mvmatrix[5] * projmatrix[5] + mvmatrix[6] * projmatrix[9] + mvmatrix[7] * projmatrix[13]; + clip[6] = mvmatrix[4] * projmatrix[2] + mvmatrix[5] * projmatrix[6] + mvmatrix[6] * projmatrix[10] + mvmatrix[7] * projmatrix[14]; + clip[7] = mvmatrix[4] * projmatrix[3] + mvmatrix[5] * projmatrix[7] + mvmatrix[6] * projmatrix[11] + mvmatrix[7] * projmatrix[15]; + + clip[8] = mvmatrix[8] * projmatrix[0] + mvmatrix[9] * projmatrix[4] + mvmatrix[10] * projmatrix[8] + mvmatrix[11] * projmatrix[12]; + clip[9] = mvmatrix[8] * projmatrix[1] + mvmatrix[9] * projmatrix[5] + mvmatrix[10] * projmatrix[9] + mvmatrix[11] * projmatrix[13]; + clip[10] = mvmatrix[8] * projmatrix[2] + mvmatrix[9] * projmatrix[6] + mvmatrix[10] * projmatrix[10] + mvmatrix[11] * projmatrix[14]; + clip[11] = mvmatrix[8] * projmatrix[3] + mvmatrix[9] * projmatrix[7] + mvmatrix[10] * projmatrix[11] + mvmatrix[11] * projmatrix[15]; + + clip[12] = mvmatrix[12] * projmatrix[0] + mvmatrix[13] * projmatrix[4] + mvmatrix[14] * projmatrix[8] + mvmatrix[15] * projmatrix[12]; + clip[13] = mvmatrix[12] * projmatrix[1] + mvmatrix[13] * projmatrix[5] + mvmatrix[14] * projmatrix[9] + mvmatrix[15] * projmatrix[13]; + clip[14] = mvmatrix[12] * projmatrix[2] + mvmatrix[13] * projmatrix[6] + mvmatrix[14] * projmatrix[10] + mvmatrix[15] * projmatrix[14]; + clip[15] = mvmatrix[12] * projmatrix[3] + mvmatrix[13] * projmatrix[7] + mvmatrix[14] * projmatrix[11] + mvmatrix[15] * projmatrix[15]; + + // Right plane + frustum[0][0] = clip[3] - clip[0]; + frustum[0][1] = clip[7] - clip[4]; + frustum[0][2] = clip[11] - clip[8]; + frustum[0][3] = clip[15] - clip[12]; + + // Left plane + frustum[1][0] = clip[3] + clip[0]; + frustum[1][1] = clip[7] + clip[4]; + frustum[1][2] = clip[11] + clip[8]; + frustum[1][3] = clip[15] + clip[12]; + + // Bottom plane + frustum[2][0] = clip[3] + clip[1]; + frustum[2][1] = clip[7] + clip[5]; + frustum[2][2] = clip[11] + clip[9]; + frustum[2][3] = clip[15] + clip[13]; + + // Top plane + frustum[3][0] = clip[3] - clip[1]; + frustum[3][1] = clip[7] - clip[5]; + frustum[3][2] = clip[11] - clip[9]; + frustum[3][3] = clip[15] - clip[13]; + + // Far plane + frustum[4][0] = clip[3] - clip[2]; + frustum[4][1] = clip[7] - clip[6]; + frustum[4][2] = clip[11] - clip[10]; + frustum[4][3] = clip[15] - clip[14]; + + // Near plane + frustum[5][0] = clip[3] + clip[2]; + frustum[5][1] = clip[7] + clip[6]; + frustum[5][2] = clip[11] + clip[10]; + frustum[5][3] = clip[15] + clip[14]; + + /* normalize the right plane */ + t = sqrt(frustum[0][0]*frustum[0][0] + + frustum[0][1]*frustum[0][1] + + frustum[0][2]*frustum[0][2]); + frustum[0][0] /= t; + frustum[0][1] /= t; + frustum[0][2] /= t; + frustum[0][3] /= t; + + /* calculate left plane */ + frustum[1][0] = clip[ 3] + clip[ 0]; + frustum[1][1] = clip[ 7] + clip[ 4]; + frustum[1][2] = clip[11] + clip[ 8]; + frustum[1][3] = clip[15] + clip[12]; + + /* normalize the left plane */ + t = sqrt(frustum[1][0]*frustum[1][0] + + frustum[1][1]*frustum[1][1] + + frustum[1][2]*frustum[1][2]); + frustum[1][0] /= t; + frustum[1][1] /= t; + frustum[1][2] /= t; + frustum[1][3] /= t; + + /* calculate the bottom plane */ + frustum[2][0] = clip[ 3] + clip[ 1]; + frustum[2][1] = clip[ 7] + clip[ 5]; + frustum[2][2] = clip[11] + clip[ 9]; + frustum[2][3] = clip[15] + clip[13]; + + /* normalize the bottom plane */ + t = sqrt(frustum[2][0]*frustum[2][0] + + frustum[2][1]*frustum[2][1] + + frustum[2][2]*frustum[2][2]); + frustum[2][0] /= t; + frustum[2][1] /= t; + frustum[2][2] /= t; + frustum[2][3] /= t; + + /* calculate the top plane */ + frustum[3][0] = clip[ 3] - clip[ 1]; + frustum[3][1] = clip[ 7] - clip[ 5]; + frustum[3][2] = clip[11] - clip[ 9]; + frustum[3][3] = clip[15] - clip[13]; + + /* normalize the top plane */ + t = sqrt(frustum[3][0]*frustum[3][0] + + frustum[3][1]*frustum[3][1] + + frustum[3][2]*frustum[3][2]); + frustum[3][0] /= t; + frustum[3][1] /= t; + frustum[3][2] /= t; + frustum[3][3] /= t; + + /* calculate the far plane */ + frustum[4][0] = clip[ 3] - clip[ 2]; + frustum[4][1] = clip[ 7] - clip[ 6]; + frustum[4][2] = clip[11] - clip[10]; + frustum[4][3] = clip[15] - clip[14]; + + /* normalize the far plane */ + t = sqrt(frustum[4][0]*frustum[4][0] + + frustum[4][1]*frustum[4][1] + + frustum[4][2]*frustum[4][2]); + frustum[4][0] /= t; + frustum[4][1] /= t; + frustum[4][2] /= t; + frustum[4][3] /= t; + + /* calculate the near plane */ + frustum[5][0] = clip[ 3] + clip[ 2]; + frustum[5][1] = clip[ 7] + clip[ 6]; + frustum[5][2] = clip[11] + clip[10]; + frustum[5][3] = clip[15] + clip[14]; + + /* normalize the near plane */ + t = sqrt(frustum[5][0]*frustum[5][0] + + frustum[5][1]*frustum[5][1] + + frustum[5][2]*frustum[5][2]); + frustum[5][0] /= t; + frustum[5][1] /= t; + frustum[5][2] /= t; + frustum[5][3] /= t; + +} + +int FRUSTUM:: + CubeInFrustum(float x, float y, float z, float size) { + int c, c2; + + c2 = 0; + for(int i=0; i<6; i++) { + c=0; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y-size) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y-size) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y+size) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y+size) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y-size) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y-size) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y+size) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y+size) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(c==0) + return 0; + if(c==8) + c2++; + } + if(c2>=6) + return 2; + else + return 1; +} + +int FRUSTUM:: + CubeInFrustum(float x, float y, float z, float size, float height) { + int c, c2; + + c2 = 0; + for(int i=0; i<6; i++) { + c=0; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y-height) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y-height) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y+height) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y+height) + frustum[i][2] * (z-size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y-height) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y-height) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x-size) + frustum[i][1] * (y+height) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(frustum[i][0] * (x+size) + frustum[i][1] * (y+height) + frustum[i][2] * (z+size) + frustum[i][3] > 0) + c++; + if(c==0) + return 0; + if(c==8) + c2++; + } + if(c2>=6) + return 2; + else + return 1; +} + +int FRUSTUM:: + SphereInFrustum(float x, float y, float z, float radius) { + int c2; + + c2 = 0; + for(int i=0; i<6; i++) { + if(frustum[i][0] * x + frustum[i][1] * y + frustum[i][2] * z + frustum[i][3] > -1*radius) + c2++; + else + return 0; + } + if(c2>=6) + return 2; + else + return 1; +} |