diff options
| -rw-r--r-- | source/blender/physics/intern/BPH_mass_spring.cpp | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/source/blender/physics/intern/BPH_mass_spring.cpp b/source/blender/physics/intern/BPH_mass_spring.cpp index 3b6e39ef48f..051f11aa1d9 100644 --- a/source/blender/physics/intern/BPH_mass_spring.cpp +++ b/source/blender/physics/intern/BPH_mass_spring.cpp @@ -137,6 +137,35 @@ static float cloth_calc_volume(ClothModifierData *clmd) return vol; } +static float cloth_calc_rest_volume(ClothModifierData *clmd) +{ + /* Calculate the (closed) cloth volume. */ + Cloth *cloth = clmd->clothObject; + const MVertTri *tri = cloth->tri; + const ClothVertex *v = cloth->verts; + float weights[3] = {1.0f, 1.0f, 1.0f}; + float vol = 0; + + /* Early exit for hair, as it never has volume. */ + if (clmd->hairdata) { + return 0.0f; + } + + for (unsigned int i = 0; i < cloth->primitive_num; i++) { + const MVertTri *vt = &tri[i]; + + if (cloth_get_pressure_weights(clmd, vt, weights)) { + vol += volume_tri_tetrahedron_signed_v3_6x( + v[vt->tri[0]].xrest, v[vt->tri[1]].xrest, v[vt->tri[2]].xrest); + } + } + + /* We need to divide by 6 to get the actual volume. */ + vol = vol / 6.0f; + + return vol; +} + static float cloth_calc_average_pressure(ClothModifierData *clmd, const float *vertex_pressure) { Cloth *cloth = clmd->clothObject; @@ -219,7 +248,7 @@ void BKE_cloth_solver_set_volume(ClothModifierData *clmd) { Cloth *cloth = clmd->clothObject; - cloth->initial_mesh_volume = cloth_calc_volume(clmd); + cloth->initial_mesh_volume = cloth_calc_rest_volume(clmd); } /* Init constraint matrix |