diff options
-rw-r--r-- | source/blender/blenkernel/intern/collision.c | 41 | ||||
-rw-r--r-- | source/blender/blenkernel/intern/editmesh_bvh.c | 3 | ||||
-rw-r--r-- | source/blender/blenlib/BLI_math_geom.h | 22 | ||||
-rw-r--r-- | source/blender/blenlib/intern/math_geom.c | 238 | ||||
-rw-r--r-- | source/blender/draw/intern/draw_cache_extract_mesh.c | 3 | ||||
-rw-r--r-- | source/blender/python/mathutils/mathutils_bvhtree.c | 4 |
6 files changed, 178 insertions, 133 deletions
diff --git a/source/blender/blenkernel/intern/collision.c b/source/blender/blenkernel/intern/collision.c index 31d49dd4508..f358355912b 100644 --- a/source/blender/blenkernel/intern/collision.c +++ b/source/blender/blenkernel/intern/collision.c @@ -212,7 +212,6 @@ static float compute_collision_point_tri_tri(const float a1[3], float dist = FLT_MAX; float tmp_co1[3], tmp_co2[3]; float isect_a[3], isect_b[3]; - int isect_count = 0; float tmp, tmp_vec[3]; float normal[3], cent[3]; bool backside = false; @@ -226,38 +225,16 @@ static float compute_collision_point_tri_tri(const float a1[3], copy_v3_v3(b[2], b3); /* Find intersections. */ - for (int i = 0; i < 3; i++) { - if (isect_line_segment_tri_v3(a[i], a[next_ind(i)], b[0], b[1], b[2], &tmp, NULL)) { - interp_v3_v3v3(isect_a, a[i], a[next_ind(i)], tmp); - isect_count++; - } - } - - if (isect_count == 0) { - for (int i = 0; i < 3; i++) { - if (isect_line_segment_tri_v3(b[i], b[next_ind(i)], a[0], a[1], a[2], &tmp, NULL)) { - isect_count++; - } - } - } - else if (isect_count == 1) { - for (int i = 0; i < 3; i++) { - if (isect_line_segment_tri_v3(b[i], b[next_ind(i)], a[0], a[1], a[2], &tmp, NULL)) { - interp_v3_v3v3(isect_b, b[i], b[next_ind(i)], tmp); - break; - } - } - } + int tri_a_edge_isect_count; + const bool is_intersecting = isect_tri_tri_v3_ex( + a, b, isect_a, isect_b, &tri_a_edge_isect_count); /* Determine collision side. */ if (culling) { normal_tri_v3(normal, b[0], b[1], b[2]); mid_v3_v3v3v3(cent, b[0], b[1], b[2]); - if (isect_count == 2) { - backside = true; - } - else if (isect_count == 0) { + if (!is_intersecting) { for (int i = 0; i < 3; i++) { sub_v3_v3v3(tmp_vec, a[i], cent); if (dot_v3v3(tmp_vec, normal) < 0.0f) { @@ -266,12 +243,16 @@ static float compute_collision_point_tri_tri(const float a1[3], } } } + else if (tri_a_edge_isect_count != 1) { + /* It is not Edge intersection. */ + backside = true; + } } else if (use_normal) { normal_tri_v3(normal, b[0], b[1], b[2]); } - if (isect_count == 1) { + if (tri_a_edge_isect_count == 1) { /* Edge intersection. */ copy_v3_v3(r_a, isect_a); copy_v3_v3(r_b, isect_b); @@ -383,7 +364,7 @@ static float compute_collision_point_tri_tri(const float a1[3], } /* Closest edge. */ - if (isect_count == 0) { + if (!is_intersecting) { for (int i = 0; i < 3; i++) { for (int j = 0; j < 3; j++) { isect_seg_seg_v3(a[i], a[next_ind(i)], b[j], b[next_ind(j)], tmp_co1, tmp_co2); @@ -398,7 +379,7 @@ static float compute_collision_point_tri_tri(const float a1[3], } } - if (isect_count == 0) { + if (!is_intersecting) { sub_v3_v3v3(r_vec, r_a, r_b); dist = sqrtf(dist); } diff --git a/source/blender/blenkernel/intern/editmesh_bvh.c b/source/blender/blenkernel/intern/editmesh_bvh.c index 72793919570..dc194f0077c 100644 --- a/source/blender/blenkernel/intern/editmesh_bvh.c +++ b/source/blender/blenkernel/intern/editmesh_bvh.c @@ -563,8 +563,7 @@ static bool bmbvh_overlap_cb(void *userdata, int index_a, int index_b, int UNUSE } } - return (isect_tri_tri_epsilon_v3( - UNPACK3(tri_a_co), UNPACK3(tri_b_co), ix_pair[0], ix_pair[1], data->epsilon) && + return (isect_tri_tri_v3(UNPACK3(tri_a_co), UNPACK3(tri_b_co), ix_pair[0], ix_pair[1]) && /* if we share a vertex, check the intersection isn't a 'point' */ ((verts_shared == 0) || (len_squared_v3v3(ix_pair[0], ix_pair[1]) > data->epsilon))); } diff --git a/source/blender/blenlib/BLI_math_geom.h b/source/blender/blenlib/BLI_math_geom.h index 3d1edb9c3b1..213f5a029b0 100644 --- a/source/blender/blenlib/BLI_math_geom.h +++ b/source/blender/blenlib/BLI_math_geom.h @@ -402,15 +402,19 @@ bool isect_ray_tri_epsilon_v3(const float ray_origin[3], float *r_lambda, float r_uv[2], const float epsilon); -bool isect_tri_tri_epsilon_v3(const float t_a0[3], - const float t_a1[3], - const float t_a2[3], - const float t_b0[3], - const float t_b1[3], - const float t_b2[3], - float r_i1[3], - float r_i2[3], - const float epsilon); +bool isect_tri_tri_v3_ex(const float tri_a[3][3], + const float tri_b[3][3], + float r_i1[3], + float r_i2[3], + int *r_tri_a_edge_isect_count); +bool isect_tri_tri_v3(const float t_a0[3], + const float t_a1[3], + const float t_a2[3], + const float t_b0[3], + const float t_b1[3], + const float t_b2[3], + float r_i1[3], + float r_i2[3]); bool isect_tri_tri_v2(const float p1[2], const float q1[2], diff --git a/source/blender/blenlib/intern/math_geom.c b/source/blender/blenlib/intern/math_geom.c index 7717c2f26ff..1afcf83bf73 100644 --- a/source/blender/blenlib/intern/math_geom.c +++ b/source/blender/blenlib/intern/math_geom.c @@ -2300,109 +2300,171 @@ bool isect_plane_plane_v3(const float plane_a[4], /** * Intersect two triangles. * - * \param r_i1, r_i2: Optional arguments to retrieve the overlapping edge between the 2 triangles. + * \param r_i1, r_i2: Retrieve the overlapping edge between the 2 triangles. + * \param r_tri_a_edge_isect_count: Indicates how many edges in the first triangle are intersected. * \return true when the triangles intersect. * + * \note If it exists, \a r_i1 will be a point on the edge of the 1st triangle. * \note intersections between coplanar triangles are currently undetected. */ -bool isect_tri_tri_epsilon_v3(const float t_a0[3], - const float t_a1[3], - const float t_a2[3], - const float t_b0[3], - const float t_b1[3], - const float t_b2[3], - float r_i1[3], - float r_i2[3], - const float epsilon) -{ - const float *tri_pair[2][3] = {{t_a0, t_a1, t_a2}, {t_b0, t_b1, t_b2}}; - float plane_a[4], plane_b[4]; - float plane_co[3], plane_no[3]; - - BLI_assert((r_i1 != NULL) == (r_i2 != NULL)); - - /* normalizing is needed for small triangles T46007 */ - normal_tri_v3(plane_a, UNPACK3(tri_pair[0])); - normal_tri_v3(plane_b, UNPACK3(tri_pair[1])); - - plane_a[3] = -dot_v3v3(plane_a, t_a0); - plane_b[3] = -dot_v3v3(plane_b, t_b0); - - if (isect_plane_plane_v3(plane_a, plane_b, plane_co, plane_no) && - (normalize_v3(plane_no) > epsilon)) { - /** - * Implementation note: its simpler to project the triangles onto the intersection plane - * before intersecting their edges with the ray, defined by 'isect_plane_plane_v3'. - * This way we can use 'line_point_factor_v3_ex' to see if an edge crosses 'co_proj', - * then use the factor to calculate the world-space point. - */ - struct { - float min, max; - } range[2] = {{FLT_MAX, -FLT_MAX}, {FLT_MAX, -FLT_MAX}}; - int t; - float co_proj[3]; - - closest_to_plane3_normalized_v3(co_proj, plane_no, plane_co); - - /* For both triangles, find the overlap with the line defined by the ray [co_proj, plane_no]. - * When the ranges overlap we know the triangles do too. */ - for (t = 0; t < 2; t++) { - int j, j_prev; - float tri_proj[3][3]; - - closest_to_plane3_normalized_v3(tri_proj[0], plane_no, tri_pair[t][0]); - closest_to_plane3_normalized_v3(tri_proj[1], plane_no, tri_pair[t][1]); - closest_to_plane3_normalized_v3(tri_proj[2], plane_no, tri_pair[t][2]); - - for (j = 0, j_prev = 2; j < 3; j_prev = j++) { - /* note that its important to have a very small nonzero epsilon here - * otherwise this fails for very small faces. - * However if its too small, large adjacent faces will count as intersecting */ - const float edge_fac = line_point_factor_v3_ex( - co_proj, tri_proj[j_prev], tri_proj[j], 1e-10f, -1.0f); - /* ignore collinear lines, they are either an edge shared between 2 tri's - * (which runs along [co_proj, plane_no], but can be safely ignored). - * - * or a collinear edge placed away from the ray - - * which we don't intersect with & can ignore. */ - if (UNLIKELY(edge_fac == -1.0f)) { - /* pass */ - } - /* Important to include 0.0f and 1.0f as one of the triangles vertices may be placed - * exactly on the plane. In this case both it's edges will have a factor of 0 or 1, - * but not be going through the plane. See T73566. */ - else if (edge_fac >= 0.0f && edge_fac <= 1.0f) { - float ix_tri[3]; - float span_fac; - - interp_v3_v3v3(ix_tri, tri_pair[t][j_prev], tri_pair[t][j], edge_fac); - /* the actual distance, since 'plane_no' is normalized */ - span_fac = dot_v3v3(plane_no, ix_tri); - - range[t].min = min_ff(range[t].min, span_fac); - range[t].max = max_ff(range[t].max, span_fac); - } - } +bool isect_tri_tri_v3_ex(const float tri_a[3][3], + const float tri_b[3][3], + float r_i1[3], + float r_i2[3], + int *r_tri_a_edge_isect_count) +{ + struct { + /* Factor that indicates the position of the intersection point on the line + * that intersects the planes of the triangles. */ + float min, max; + /* Intersection point location. */ + float loc[2][3]; + } range[2]; + + float side[2][3]; + float ba[3], bc[3], plane_a[4], plane_b[4]; + *r_tri_a_edge_isect_count = 0; + + sub_v3_v3v3(ba, tri_a[0], tri_a[1]); + sub_v3_v3v3(bc, tri_a[2], tri_a[1]); + cross_v3_v3v3(plane_a, ba, bc); + plane_a[3] = -dot_v3v3(tri_a[1], plane_a); + side[1][0] = plane_point_side_v3(plane_a, tri_b[0]); + side[1][1] = plane_point_side_v3(plane_a, tri_b[1]); + side[1][2] = plane_point_side_v3(plane_a, tri_b[2]); + + if (!side[1][0] && !side[1][1] && !side[1][2]) { + /* Coplanar case is not supported. */ + return false; + } - if (range[t].min == FLT_MAX) { - return false; + if ((side[1][0] && side[1][1] && side[1][2]) && (side[1][0] < 0.0f) == (side[1][1] < 0.0f) && + (side[1][0] < 0.0f) == (side[1][2] < 0.0f)) { + /* All vertices of the 2nd triangle are positioned on the same side to the + * plane defined by the 1st triangle. */ + return false; + } + + sub_v3_v3v3(ba, tri_b[0], tri_b[1]); + sub_v3_v3v3(bc, tri_b[2], tri_b[1]); + cross_v3_v3v3(plane_b, ba, bc); + plane_b[3] = -dot_v3v3(tri_b[1], plane_b); + side[0][0] = plane_point_side_v3(plane_b, tri_a[0]); + side[0][1] = plane_point_side_v3(plane_b, tri_a[1]); + side[0][2] = plane_point_side_v3(plane_b, tri_a[2]); + if ((side[0][0] && side[0][1] && side[0][2]) && (side[0][0] < 0.0f) == (side[0][1] < 0.0f) && + (side[0][0] < 0.0f) == (side[0][2] < 0.0f)) { + /* All vertices of the 1st triangle are positioned on the same side to the + * plane defined by the 2nd triangle. */ + return false; + } + + /* Direction of the line that intersects the planes of the triangles. */ + float isect_dir[3]; + cross_v3_v3v3(isect_dir, plane_a, plane_b); + for (int i = 0; i < 2; i++) { + const float(*tri)[3] = i == 0 ? tri_a : tri_b; + /* Rearrange the triangle so that the vertex that is alone on one side + * of the plane is located at index 1. */ + int tri_i[3]; + if ((side[i][0] && side[i][1]) && (side[i][0] < 0.0f) == (side[i][1] < 0.0f)) { + tri_i[0] = 1; + tri_i[1] = 2; + tri_i[2] = 0; + } + else if ((side[i][1] && side[i][2]) && (side[i][1] < 0.0f) == (side[i][2] < 0.0f)) { + tri_i[0] = 2; + tri_i[1] = 0; + tri_i[2] = 1; + } + else { + tri_i[0] = 0; + tri_i[1] = 1; + tri_i[2] = 2; + } + + float dot_b = dot_v3v3(isect_dir, tri[tri_i[1]]); + range[i].min = dot_b; + range[i].max = dot_b; + + float sidec = side[i][tri_i[1]]; + if (sidec) { + float dot_a = dot_v3v3(isect_dir, tri[tri_i[0]]); + float dot_c = dot_v3v3(isect_dir, tri[tri_i[2]]); + float fac0 = sidec / (sidec - side[i][tri_i[0]]); + float fac1 = sidec / (sidec - side[i][tri_i[2]]); + float offset0 = fac0 * (dot_a - dot_b); + float offset1 = fac1 * (dot_c - dot_b); + if (offset0 > offset1) { + /* Sort min max. */ + SWAP(float, offset0, offset1); + SWAP(float, fac0, fac1); + SWAP(int, tri_i[0], tri_i[2]); } + + range[i].min += offset0; + range[i].max += offset1; + interp_v3_v3v3(range[i].loc[0], tri[tri_i[1]], tri[tri_i[0]], fac0); + interp_v3_v3v3(range[i].loc[1], tri[tri_i[1]], tri[tri_i[2]], fac1); + } + else { + copy_v3_v3(range[i].loc[0], tri[tri_i[1]]); + copy_v3_v3(range[i].loc[1], tri[tri_i[1]]); } + } - if (((range[0].min > range[1].max) || (range[0].max < range[1].min)) == 0) { - if (r_i1 && r_i2) { - project_plane_normalized_v3_v3v3(plane_co, plane_co, plane_no); - madd_v3_v3v3fl(r_i1, plane_co, plane_no, max_ff(range[0].min, range[1].min)); - madd_v3_v3v3fl(r_i2, plane_co, plane_no, min_ff(range[0].max, range[1].max)); + if ((range[0].max >= range[1].min) && (range[0].min <= range[1].max)) { + /* The triangles intersect because they overlap on the intersection line. + * Now identify the two points of intersection that are in the middle to get the actual + * intersection between the triangles. (B--C from A--B--C--D) */ + if (range[0].min >= range[1].min) { + copy_v3_v3(r_i1, range[0].loc[0]); + if (range[0].max <= range[1].max) { + copy_v3_v3(r_i2, range[0].loc[1]); + *r_tri_a_edge_isect_count = 2; + } + else { + copy_v3_v3(r_i2, range[1].loc[1]); + *r_tri_a_edge_isect_count = 1; } - - return true; } + else { + if (range[0].max <= range[1].max) { + copy_v3_v3(r_i1, range[0].loc[1]); + copy_v3_v3(r_i2, range[1].loc[0]); + *r_tri_a_edge_isect_count = 1; + } + else { + copy_v3_v3(r_i1, range[1].loc[0]); + copy_v3_v3(r_i2, range[1].loc[1]); + } + } + return true; } return false; } +bool isect_tri_tri_v3(const float t_a0[3], + const float t_a1[3], + const float t_a2[3], + const float t_b0[3], + const float t_b1[3], + const float t_b2[3], + float r_i1[3], + float r_i2[3]) +{ + float tri_a[3][3], tri_b[3][3]; + int dummy; + copy_v3_v3(tri_a[0], t_a0); + copy_v3_v3(tri_a[1], t_a1); + copy_v3_v3(tri_a[2], t_a2); + copy_v3_v3(tri_b[0], t_b0); + copy_v3_v3(tri_b[1], t_b1); + copy_v3_v3(tri_b[2], t_b2); + return isect_tri_tri_v3_ex(tri_a, tri_b, r_i1, r_i2, &dummy); +} + /* -------------------------------------------------------------------- */ /** \name Tri-Tri Intersect 2D * diff --git a/source/blender/draw/intern/draw_cache_extract_mesh.c b/source/blender/draw/intern/draw_cache_extract_mesh.c index a22d4cc95a2..934b47d583e 100644 --- a/source/blender/draw/intern/draw_cache_extract_mesh.c +++ b/source/blender/draw/intern/draw_cache_extract_mesh.c @@ -4046,8 +4046,7 @@ static bool bvh_overlap_cb(void *userdata, int index_a, int index_b, int UNUSED( return false; } - return (isect_tri_tri_epsilon_v3( - UNPACK3(tri_a_co), UNPACK3(tri_b_co), ix_pair[0], ix_pair[1], data->epsilon) && + return (isect_tri_tri_v3(UNPACK3(tri_a_co), UNPACK3(tri_b_co), ix_pair[0], ix_pair[1]) && /* if we share a vertex, check the intersection isn't a 'point' */ ((verts_shared == 0) || (len_squared_v3v3(ix_pair[0], ix_pair[1]) > data->epsilon))); } diff --git a/source/blender/python/mathutils/mathutils_bvhtree.c b/source/blender/python/mathutils/mathutils_bvhtree.c index 80a72696d77..0c53639c67d 100644 --- a/source/blender/python/mathutils/mathutils_bvhtree.c +++ b/source/blender/python/mathutils/mathutils_bvhtree.c @@ -549,8 +549,8 @@ static bool py_bvhtree_overlap_cb(void *userdata, int index_a, int index_b, int } } - return (isect_tri_tri_epsilon_v3( - UNPACK3(tri_a_co), UNPACK3(tri_b_co), ix_pair[0], ix_pair[1], data->epsilon) && + return (isect_tri_tri_v3( + UNPACK3(tri_a_co), UNPACK3(tri_b_co), ix_pair[0], ix_pair[1]) && ((verts_shared == 0) || (len_squared_v3v3(ix_pair[0], ix_pair[1]) > data->epsilon))); } |