3DPrinting/PrusaSlicer-NonPlainar
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Another bulk of bug fixes. Some problems however persist, support points are still placed on weird spots

Browse source
This commit is contained in:
PavelMikus 2022-04-29 17:19:26 +02:00
parent 6caec6926c
commit 6f6a0e7efd
2 changed files with 74 additions and 66 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

133
src/libslic3r/SupportableIssuesSearch.cpp
View file

@ -58,11 +58,12 @@ struct Cell {
struct CentroidAccumulator {
Polygon convex_hull { };
Points points { };
Vec3d accumulated_value = Vec3d::Zero();
Vec3f accumulated_value = Vec3f::Zero();
float accumulated_volume { };
const double base_height { };
float base_area { };
const float base_height { };
explicit CentroidAccumulator(double base_height) :
explicit CentroidAccumulator(float base_height) :
base_height(base_height) {
}
@ -80,7 +81,7 @@ struct CentroidAccumulators {
acccumulators.reserve(reserve_count);
}
CentroidAccumulator& create_accumulator(int id, double base_height) {
CentroidAccumulator& create_accumulator(int id, float base_height) {
mapping[id] = acccumulators.size();
acccumulators.push_back(CentroidAccumulator { base_height });
return this->access(id);
@ -100,6 +101,7 @@ struct CentroidAccumulators {
to_acc.accumulated_volume += from_acc.accumulated_volume;
to_acc.points.insert(to_acc.points.end(), from_acc.points.begin(), from_acc.points.end());
to_acc.calculate_base_hull();
to_acc.base_area += from_acc.base_area;
mapping[from_id] = mapping[to_id];
}
};
@ -265,7 +267,7 @@ struct BalanceDistributionGrid {
Vec3crd cell_center = this->get_cell_center(
Vec3i(current_coords.x(), current_coords.y(), local_z_index_offset));
acc.points.push_back(Point(cell_center.head<2>()));
acc.accumulated_value += cell_center.cast<double>() * cell.volume;
acc.accumulated_value += unscale(cell_center).cast<float>() * cell.volume;
acc.accumulated_volume += cell.volume;
for (int y_offset = -1; y_offset <= 1; ++y_offset) {
@ -279,6 +281,7 @@ struct BalanceDistributionGrid {
}
next_island_id--;
acc.calculate_base_hull();
acc.base_area = unscale<float>(unscale<float>(acc.convex_hull.area())); //apply unscale 2x, it has units of area
}
}
}
@ -295,6 +298,7 @@ struct BalanceDistributionGrid {
issues.supports_nedded[index].position.z());
acc.points.push_back(Point(scaled(Vec2f(issues.supports_nedded[index].position.head<2>()))));
acc.calculate_base_hull();
acc.base_area = params.support_points_inteface_area;
}
for (const CurledFilament &curling : issues.curling_up) {
@ -343,9 +347,10 @@ struct BalanceDistributionGrid {
accumulators.merge_to(id, min_island_id_found);
}
CentroidAccumulator &acc = accumulators.access(current.island_id);
CentroidAccumulator &acc = accumulators.access(min_island_id_found);
acc.accumulated_value += current.volume
* this->get_cell_center(this->to_global_cell_coords(Vec3i(x, y, z))).cast<double>();
* unscale(this->get_cell_center(this->to_global_cell_coords(Vec3i(x, y, z)))).cast<
float>();
acc.accumulated_volume += current.volume;
modified_acc_ids.insert(min_island_id_found);
}
@ -353,109 +358,107 @@ struct BalanceDistributionGrid {
}
}
// check stability of modified centroid accumulators.
// Stability is the amount of work needed to push the object from stable position into unstable.
// This amount of work is proportional to the increase of height of the centroid during toppling.
// image here: https://hgphysics.com/gph/c-forces/2-force-effects/1-moment/stability/
// better image in Czech here in the first question: https://www.priklady.eu/cs/fyzika/mechanika-tuheho-telesa/stabilita-teles.alej
for (int acc_id : modified_acc_ids) {
std::cout << "controlling acc id: " << acc_id << std::endl;
std::cout << "Z: " << z << " controlling acc id: " << acc_id << std::endl;
CentroidAccumulator &acc = accumulators.access(acc_id);
Vec3d centroid = acc.accumulated_value / acc.accumulated_volume;
Vec3f centroid = acc.accumulated_value / acc.accumulated_volume;
std::cout << "acc.accumulated_value : " << acc.accumulated_value.x() << " "
<< acc.accumulated_value.y() << " " << acc.accumulated_value.z() << std::endl;
std::cout << "acc.accumulated_volume : " << acc.accumulated_volume << std::endl;
std::cout << "centorid: " << centroid.x() << " " << centroid.y() << " " << centroid.z() << std::endl;
std::cout << "centroid: " << centroid.x() << " " << centroid.y() << " " << centroid.z() << std::endl;
//determine signed shortest distance to the convex hull
Point centroid_base_projection = Point(centroid.head<2>().cast<coord_t>());
Point centroid_base_projection = Point(scaled(Vec2f(centroid.head<2>())));
Point pivot;
double distance_sq = std::numeric_limits<double>::max();
double distance_scaled_sq = std::numeric_limits<double>::max();
bool inside = true;
if (acc.convex_hull.points.size() == 1) {
pivot = acc.convex_hull.points[0];
distance_sq = (pivot - centroid_base_projection).squaredNorm();
distance_scaled_sq = (pivot - centroid_base_projection).squaredNorm();
inside = true;
} else {
for (Line line : acc.convex_hull.lines()) {
Point closest_point;
double dist_sq = line.distance_to_squared(centroid_base_projection, &closest_point);
if (dist_sq < distance_sq) {
if (dist_sq < distance_scaled_sq) {
pivot = closest_point;
distance_sq = dist_sq;
distance_scaled_sq = dist_sq;
}
if (float(angle(line.b - line.a, centroid_base_projection - line.b)) < 0) {
if ((centroid_base_projection - closest_point).cast<double>().dot(line.normal().cast<double>())
> 0) {
inside = false;
}
}
}
std::cout << "centoroid inside ? " << inside << " and distance is: " << distance_sq << std::endl;
float centroid_pivot_distance = unscaled(sqrt(distance_scaled_sq));
float base_center_pivot_distance = float(unscale(Vec2crd(acc.convex_hull.centroid() - pivot)).norm());
std::cout << "centroid inside ? " << inside << " and distance is: " << centroid_pivot_distance
<< std::endl;
bool additional_supports_needed = false;
double base_area = std::max(acc.convex_hull.area(), scale_(5.0)); // assume 5 mm^2 area for support points and other degenerate bases
double sticking_force = base_area
* (acc.base_height == 0 ? scale_(params.base_adhesion) : scale_(params.support_adhesion));
float sticking_force = acc.base_area
* (acc.base_height == 0 ? params.base_adhesion : params.support_adhesion);
float sticking_torque = base_center_pivot_distance * sticking_force;
std::cout << "stcking force: " << sticking_force << std::endl;
std::cout << "sticking force: " << sticking_force << " sticking torque: " << sticking_torque
<< std::endl;
if (inside) {
double toppling_force = (Vec2d(sqrt(distance_sq), centroid.z() - acc.base_height).norm()
- centroid.z())
* acc.accumulated_volume;
sticking_force += toppling_force;
std::cout << "toppling force: " << toppling_force << std::endl;
}
float xy_movement_force = acc.accumulated_volume * params.filament_density * params.max_acceleration;
float xy_movement_torque = xy_movement_force * centroid_pivot_distance;
double y_movement_force = 0.5f * acc.accumulated_volume * scale_(params.top_object_movement_speed)
* scale_(params.top_object_movement_speed);
std::cout << "y_movement_force: " << y_movement_force << std::endl;
if (sticking_force < y_movement_force) {
additional_supports_needed = true;
}
std::cout << "xy_movement_force: " << xy_movement_force << " xy_movement_torque: "
<< xy_movement_torque << std::endl;
float weight_torque = 0;
if (!inside) {
double torque = sqrt(distance_sq) * scale_(scale_(scale_(acc.accumulated_volume))); // if sticking force is computed with scaled adhesion, than torque needs scaled volume as well
float weight = acc.accumulated_volume * params.filament_density * 10000.0f;
weight_torque = centroid_pivot_distance * weight;
std::cout << "torque: " << torque << std::endl;
if (torque > sticking_force) { //comparing apples and oranges; but we are far beyond physical simulation
additional_supports_needed = true;
}
std::cout << "weight: " << weight << " weight_torque: " << weight_torque << std::endl;
}
float total_momentum = sticking_torque - xy_movement_torque - weight_torque;
additional_supports_needed = total_momentum < 0;
std::cout << "total_momentum: " << total_momentum << std::endl;
std::cout << "additional supports needed: " << additional_supports_needed << std::endl;
if (additional_supports_needed) {
Vec2crd attractor_dir =
inside ? pivot - centroid_base_projection : centroid_base_projection - pivot;
Vec2d attractor = centroid_base_projection.cast<double>()
+ (1e9 * attractor_dir.cast<double>().normalized());
Vec2f attractor_dir =
unscale(Vec2crd(inside ?
pivot - centroid_base_projection :
centroid_base_projection - pivot)).cast<float>().normalized();
Vec2f attractor = unscale(centroid_base_projection).cast<float>() + 10000 * attractor_dir;
std::cout << " attractor: " << attractor.x() << " | " << attractor.y() << std::endl;
double min_dist = std::numeric_limits<double>::max();
Vec3d support_point = centroid;
Vec3f support_point = centroid;
for (int y = 0; y < global_cell_count.y(); ++y) {
for (int x = 0; x < global_cell_count.x(); ++x) {
Cell &cell = this->access_cell(Vec3i(x, y, 0));
if (cell.island_id == acc_id) {
Vec3d cell_center =
this->get_cell_center(this->to_global_cell_coords(Vec3i(x, y, z))).cast<
double>();
double dist_sq = (cell_center.head<2>() - attractor).squaredNorm();
Cell &cell = this->access_cell(Vec3i(x, y, z));
if (&accumulators.access(cell.island_id) == &acc) {
Vec3f cell_center =
unscale(this->get_cell_center(this->to_global_cell_coords(Vec3i(x, y, z)))).cast<
float>();
float dist_sq = (cell_center.head<2>() - attractor).squaredNorm();
if (dist_sq < min_dist) {
min_dist = dist_sq;
support_point = cell_center;
std::cout << " new support point: " << support_point.x() << " | " << support_point.y() << " | " << support_point.z() << std::endl;
}
}
}
}
issues.supports_nedded.emplace_back(unscale(support_point).cast<float>());
acc.points.push_back(Point(support_point.head<2>().cast<coord_t>()));
issues.supports_nedded.emplace_back(support_point);
acc.points.push_back(Point::new_scale(Vec2f(support_point.head<2>())));
acc.calculate_base_hull();
}
@ -559,7 +562,7 @@ void debug_export(Issues issues, std::string file_name) {
for (size_t i = 0; i < issues.supports_nedded.size(); ++i) {
fprintf(fp, "v %f %f %f %f %f %f\n", issues.supports_nedded[i].position(0),
issues.supports_nedded[i].position(1),
issues.supports_nedded[i].position(2), 1.0, 0.0, 0.0);
issues.supports_nedded[i].position(2), 1.0, 0.0, 1.0);
}
fclose(fp);
@ -721,9 +724,8 @@ Issues check_extrusion_entity_stability(const ExtrusionEntity *entity, float pri
if (supports_acc.distance // if unsupported distance is larger than bridge distance linearly decreased by curvature, enforce supports.
> params.bridge_distance
/ (1.0f
+ (supports_acc.max_curvature
* params.bridge_distance_decrease_by_curvature_factor / PI))) {
/ (1.0f + (supports_acc.max_curvature
* params.bridge_distance_decrease_by_curvature_factor / PI))) {
issues.supports_nedded.push_back(SupportPoint(fpoint));
supports_acc.reset();
}
@ -899,6 +901,9 @@ Issues full_search(const PrintObject *po, const Params &params) {
return left;
}
);
#ifdef DEBUG_FILES
Impl::debug_export(found_issues, "pre_issues");
#endif
grid.analyze(found_issues, params);

7
src/libslic3r/SupportableIssuesSearch.hpp
View file

@ -15,9 +15,12 @@ struct Params {
float max_unsupported_distance_factor = 1.0f; // For internal perimeters, infill, bridges etc, allow gap of [extrusion width] size, these extrusions have usually something to stick to.
float bridge_distance_decrease_by_curvature_factor = 5.0f; // allowed bridge distance = bridge_distance / ( 1 + this factor * (curvature / PI) )
float base_adhesion = 60.0f; // adhesion per mm^2 of first layer; the value should say how much *volume* it can hold per one square millimiter
float base_adhesion = 100.0f; // adhesion per mm^2 of first layer; Force needed to remove the object from the bed, divided by the adhesion area, so in Pascal units N/mm^2
float support_adhesion = 300.0f; // adhesion per mm^2 of support interface layer
float top_object_movement_speed = 200.0f; // movement speed of 200 mm/s in Y
float support_points_inteface_area = 5.0f; // mm^2
float max_acceleration = 1000.0f; // mm/s^2 ; max acceleration in XY
float filament_density = 1.25f * 0.001f; // g/mm^3
};
struct SupportPoint {