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Diffstat (limited to 'core/math/geometry.h')
-rw-r--r-- | core/math/geometry.h | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/core/math/geometry.h b/core/math/geometry.h index 3bbd1911ee..5a8e21d02b 100644 --- a/core/math/geometry.h +++ b/core/math/geometry.h @@ -1024,6 +1024,249 @@ public: static Vector<Vector3> compute_convex_mesh_points(const Plane *p_planes, int p_plane_count); +#define FINDMINMAX(x0, x1, x2, min, max) \ + min = max = x0; \ + if (x1 < min) \ + min = x1; \ + if (x1 > max) \ + max = x1; \ + if (x2 < min) \ + min = x2; \ + if (x2 > max) \ + max = x2; + + _FORCE_INLINE_ static bool planeBoxOverlap(Vector3 normal, float d, Vector3 maxbox) { + int q; + Vector3 vmin, vmax; + for (q = 0; q <= 2; q++) { + if (normal[q] > 0.0f) { + vmin[q] = -maxbox[q]; + vmax[q] = maxbox[q]; + } else { + vmin[q] = maxbox[q]; + vmax[q] = -maxbox[q]; + } + } + if (normal.dot(vmin) + d > 0.0f) + return false; + if (normal.dot(vmax) + d >= 0.0f) + return true; + + return false; + } + +/*======================== X-tests ========================*/ +#define AXISTEST_X01(a, b, fa, fb) \ + p0 = a * v0.y - b * v0.z; \ + p2 = a * v2.y - b * v2.z; \ + if (p0 < p2) { \ + min = p0; \ + max = p2; \ + } else { \ + min = p2; \ + max = p0; \ + } \ + rad = fa * boxhalfsize.y + fb * boxhalfsize.z; \ + if (min > rad || max < -rad) \ + return false; + +#define AXISTEST_X2(a, b, fa, fb) \ + p0 = a * v0.y - b * v0.z; \ + p1 = a * v1.y - b * v1.z; \ + if (p0 < p1) { \ + min = p0; \ + max = p1; \ + } else { \ + min = p1; \ + max = p0; \ + } \ + rad = fa * boxhalfsize.y + fb * boxhalfsize.z; \ + if (min > rad || max < -rad) \ + return false; + +/*======================== Y-tests ========================*/ +#define AXISTEST_Y02(a, b, fa, fb) \ + p0 = -a * v0.x + b * v0.z; \ + p2 = -a * v2.x + b * v2.z; \ + if (p0 < p2) { \ + min = p0; \ + max = p2; \ + } else { \ + min = p2; \ + max = p0; \ + } \ + rad = fa * boxhalfsize.x + fb * boxhalfsize.z; \ + if (min > rad || max < -rad) \ + return false; + +#define AXISTEST_Y1(a, b, fa, fb) \ + p0 = -a * v0.x + b * v0.z; \ + p1 = -a * v1.x + b * v1.z; \ + if (p0 < p1) { \ + min = p0; \ + max = p1; \ + } else { \ + min = p1; \ + max = p0; \ + } \ + rad = fa * boxhalfsize.x + fb * boxhalfsize.z; \ + if (min > rad || max < -rad) \ + return false; + + /*======================== Z-tests ========================*/ + +#define AXISTEST_Z12(a, b, fa, fb) \ + p1 = a * v1.x - b * v1.y; \ + p2 = a * v2.x - b * v2.y; \ + if (p2 < p1) { \ + min = p2; \ + max = p1; \ + } else { \ + min = p1; \ + max = p2; \ + } \ + rad = fa * boxhalfsize.x + fb * boxhalfsize.y; \ + if (min > rad || max < -rad) \ + return false; + +#define AXISTEST_Z0(a, b, fa, fb) \ + p0 = a * v0.x - b * v0.y; \ + p1 = a * v1.x - b * v1.y; \ + if (p0 < p1) { \ + min = p0; \ + max = p1; \ + } else { \ + min = p1; \ + max = p0; \ + } \ + rad = fa * boxhalfsize.x + fb * boxhalfsize.y; \ + if (min > rad || max < -rad) \ + return false; + + _FORCE_INLINE_ static bool triangle_box_overlap(const Vector3 &boxcenter, const Vector3 boxhalfsize, const Vector3 *triverts) { + + /* use separating axis theorem to test overlap between triangle and box */ + /* need to test for overlap in these directions: */ + /* 1) the {x,y,z}-directions (actually, since we use the AABB of the triangle */ + /* we do not even need to test these) */ + /* 2) normal of the triangle */ + /* 3) crossproduct(edge from tri, {x,y,z}-directin) */ + /* this gives 3x3=9 more tests */ + Vector3 v0, v1, v2; + float min, max, d, p0, p1, p2, rad, fex, fey, fez; + Vector3 normal, e0, e1, e2; + + /* This is the fastest branch on Sun */ + /* move everything so that the boxcenter is in (0,0,0) */ + + v0 = triverts[0] - boxcenter; + v1 = triverts[1] - boxcenter; + v2 = triverts[2] - boxcenter; + + /* compute triangle edges */ + e0 = v1 - v0; /* tri edge 0 */ + e1 = v2 - v1; /* tri edge 1 */ + e2 = v0 - v2; /* tri edge 2 */ + + /* Bullet 3: */ + /* test the 9 tests first (this was faster) */ + fex = Math::abs(e0.x); + fey = Math::abs(e0.y); + fez = Math::abs(e0.z); + AXISTEST_X01(e0.z, e0.y, fez, fey); + AXISTEST_Y02(e0.z, e0.x, fez, fex); + AXISTEST_Z12(e0.y, e0.x, fey, fex); + + fex = Math::abs(e1.x); + fey = Math::abs(e1.y); + fez = Math::abs(e1.z); + AXISTEST_X01(e1.z, e1.y, fez, fey); + AXISTEST_Y02(e1.z, e1.x, fez, fex); + AXISTEST_Z0(e1.y, e1.x, fey, fex); + + fex = Math::abs(e2.x); + fey = Math::abs(e2.y); + fez = Math::abs(e2.z); + AXISTEST_X2(e2.z, e2.y, fez, fey); + AXISTEST_Y1(e2.z, e2.x, fez, fex); + AXISTEST_Z12(e2.y, e2.x, fey, fex); + + /* Bullet 1: */ + /* first test overlap in the {x,y,z}-directions */ + /* find min, max of the triangle each direction, and test for overlap in */ + /* that direction -- this is equivalent to testing a minimal AABB around */ + /* the triangle against the AABB */ + + /* test in X-direction */ + FINDMINMAX(v0.x, v1.x, v2.x, min, max); + if (min > boxhalfsize.x || max < -boxhalfsize.x) + return false; + + /* test in Y-direction */ + FINDMINMAX(v0.y, v1.y, v2.y, min, max); + if (min > boxhalfsize.y || max < -boxhalfsize.y) + return false; + + /* test in Z-direction */ + FINDMINMAX(v0.z, v1.z, v2.z, min, max); + if (min > boxhalfsize.z || max < -boxhalfsize.z) + return false; + + /* Bullet 2: */ + /* test if the box intersects the plane of the triangle */ + /* compute plane equation of triangle: normal*x+d=0 */ + normal = e0.cross(e1); + d = -normal.dot(v0); /* plane eq: normal.x+d=0 */ + return planeBoxOverlap(normal, d, boxhalfsize); /* if true, box and triangle overlaps */ + } + + static Vector<Point2i> pack_rects(const Vector<Size2i> &p_sizes, const Size2i &p_atlas_size); + static Vector<Vector3i> partial_pack_rects(const Vector<Vector2i> &p_sizes, const Size2i &p_atlas_size); + + static Vector<uint32_t> generate_edf(const Vector<bool> &p_voxels, const Vector3i &p_size, bool p_negative); + static Vector<int8_t> generate_sdf8(const Vector<uint32_t> &p_positive, const Vector<uint32_t> &p_negative); + + static Vector3 triangle_get_barycentric_coords(const Vector3 &p_a, const Vector3 &p_b, const Vector3 &p_c, const Vector3 &p_pos) { + Vector3 v0 = p_b - p_a; + Vector3 v1 = p_c - p_a; + Vector3 v2 = p_pos - p_a; + + float d00 = v0.dot(v0); + float d01 = v0.dot(v1); + float d11 = v1.dot(v1); + float d20 = v2.dot(v0); + float d21 = v2.dot(v1); + float denom = (d00 * d11 - d01 * d01); + if (denom == 0) { + return Vector3(); //invalid triangle, return empty + } + float v = (d11 * d20 - d01 * d21) / denom; + float w = (d00 * d21 - d01 * d20) / denom; + float u = 1.0f - v - w; + return Vector3(u, v, w); + } + + static Color tetrahedron_get_barycentric_coords(const Vector3 &p_a, const Vector3 &p_b, const Vector3 &p_c, const Vector3 &p_d, const Vector3 &p_pos) { + Vector3 vap = p_pos - p_a; + Vector3 vbp = p_pos - p_b; + + Vector3 vab = p_b - p_a; + Vector3 vac = p_c - p_a; + Vector3 vad = p_d - p_a; + + Vector3 vbc = p_c - p_b; + Vector3 vbd = p_d - p_b; + // ScTP computes the scalar triple product +#define STP(m_a, m_b, m_c) ((m_a).dot((m_b).cross((m_c)))) + float va6 = STP(vbp, vbd, vbc); + float vb6 = STP(vap, vac, vad); + float vc6 = STP(vap, vad, vab); + float vd6 = STP(vap, vab, vac); + float v6 = 1 / STP(vab, vac, vad); + return Color(va6 * v6, vb6 * v6, vc6 * v6, vd6 * v6); +#undef STP + } + private: static Vector<Vector<Point2>> _polypaths_do_operation(PolyBooleanOperation p_op, const Vector<Point2> &p_polypath_a, const Vector<Point2> &p_polypath_b, bool is_a_open = false); static Vector<Vector<Point2>> _polypath_offset(const Vector<Point2> &p_polypath, real_t p_delta, PolyJoinType p_join_type, PolyEndType p_end_type); |