Sketcher: Dialogo
Introduzione
Se ci si trova in uno schizzo, la finestra di dialogo dello Sketcher viene visualizzata nella scheda Azioni del pannello Vista Combinata. Per entrare in uno schizzo, selezionarlo nell'albero del modello o fare doppio clic su di esso o fare clic con il pulsante destro del mouse su di esso e quindi selezionare Modifica schizzo nel menu di scelta rapida. Un'altra possibilità è fare clic sull'icona Modifica schizzo della barra degli strumenti.
La finestra di dialogo è composta dalle seguenti sezioni:
Messaggi del risolutore
Questa sezione fornisce informazioni sullo stato dello schizzo, se è sotto o sovra-vincolato e quanti gradi di libertà ha lo schizzo. Facendo clic sui gradi di libertà, gli elementi dello schizzo sottovincolato si evidenziano in verde.
Ci sono due opzioni per i messaggi del solutore:
Nome | Descrizione |
---|---|
Rimuovi automaticamente i ridondanti | Se selezionato, i nuovi vincoli creati che sarebbero ridondanti ai vincoli esistenti vengono automaticamente rimossi. La rimozione rimane silente per i vincoli che non sono dimensionali. Nota: Per i vincoli dimensionali ridondanti si viene informati che il nuovo vincolo non è valido, indipendentemente dall'utilizzo di Rimuovi automaticamente i ridondanti. |
Auto aggiorna | Se selezionato, l'intero documento viene ricalcolato dopo ogni azione di schizzo. Il vantaggio è che se per es. si modifica lo schizzo con una tasca, si vede immediatamente l'effetto. Lo svantaggio è che richiede molto tempo per i documenti complessi. Disabilitare quindi l'opzione se la modifica degli schizzi diventa lenta. |
Controlli avanzati del solutore
Questa sezione di dialogo viene visualizzata solo se si imposta l'opzione Visualizza i controlli avanzati del risolutore nella barra delle azioni nel menu delle preferenze di Sketcher.
È possibile specificare quanto segue:
Name | Description |
---|---|
Default solver | The solver that is used for solving the geometry. LevenbergMarquardt and DogLeg are trust region optimization algorithms. The BFGS solver uses the Broyden–Fletcher–Goldfarb–Shanno algorithm. |
DogLeg Gauss step | This setting is only available for the solver DogLeg. It is the step type used in the DogLeg algorithm. |
Maximum iterations | If the solver needs more iterations to find a convergence to a solution, it will stop and output that it failed. |
Sketch size multiplier | If checked, the maximum iterations will be multiplied by the number of parameters. The idea is that bigger sketches would need more iterations to converge. |
Convergence | The threshold for the squared error. This error is used to determine whether a solution converges or not. |
Eps/Eps1/Tau | These settings are only available for the solver LevenbergMarquardt. You should only change there something if you fully understand how the LevenbergMarquardt solver works. |
Tolg/Tolx/Tolf | These settings are only available for the solver DogLeg. You should only change there something if you fully understand how the DogLeg solver works. |
QR Algorithm | During diagnosing the rank of the matrix is calculated which enables to further analyze the constraint system to determine if there are redundant/conflicting constraints. The rank revealing decomposition used in FreeCAD is QR. There are two algorithms: Eigen Dense QR is a dense matrix QR with full pivoting, which is the legacy proven algorithm that works very well but it is rather slow as the system grows. The Eigen Sparse QR algorithm is an optimization for sparse matrices (having lots of zeros), which is usually much faster, since FreeCAD's systems do have a lot of zeros. |
Pivot threshold | When doing a QR, values under the pivot threshold are treated as zero. |
Redundant Solver | The solver that is used during diagnosing to determine whether a group is redundant or conflicting. |
Red. Max Iterations | The same as Maximum iterations, but for the redundant solving. |
Red. Sketch size multiplier | The same as Sketch size multiplier, but for the redundant solving. |
Red. Convergence | The same as Convergence, but for the redundant solving. |
R.Eps/R.Eps1/R.Tau | The same as Eps/Eps1/Tau, but for the redundant solving. |
R.Tolg/R.Tolx/R.Tolf | The same as Tolg/Tolx/Tolf, but for the redundant solving. |
Console Debug mode | Setting to specify the verbosity of the console output. |
Solve | With this button the solver will explicitly started. |
Restore Defaults | With this button the default solver settings will be restored. |
Nota: La maggior parte dei parametri del solutore non ha alcun uso pratico. Possono tuttavia aiutare a testare e comprendere i risolutori.
Controlli di editazione
I controlli di modifica hanno lo scopo di migliorare il flusso di lavoro. Possono anche essere impostati globalmente per tutti gli schizzi tramite le preferenze di sketcher.
È possibile impostare i seguenti controlli:
Name | Description |
---|---|
Show Grid | If checked, a grid will be shown. |
Grid size | The distance between two subsequent grid lines. Note that the default value of 0 mm will result in a 10 mm grid. |
Grid snap | If checked, new points will snap to the nearest grid line. Note that the points have already to be close to a grid line that the snap takes effect. The distance is a fifth of the value set for Grid size, so for a 10 mm grid, the snapping only occurs if the point is not more than 2 mm away from a grid line. Note: A snapped point has no coincident constraint with the grid point it snapped to. |
Auto constraints | If checked, the sketcher proposes automatically sensible constraints. If you draw for example a polyline and point towards the bottom, you will see that the sketcher proposes a vertical constraint:. If you set now a point the drawn line segment will get the vertical constraint. |
Avoid redundant auto constraints | If checked, the sketcher tries not to propose redundant auto constraints. This option only has an effect if also the option Auto constraints is used. |
Rendering order | The order how sketches are rendered. To change it, drag and drop a geometry type to the top or bottom. |
Vincoli
Questa sezione elenca i vincoli dello schizzo. Deselezionando un vincolo nell'elenco è possibile nasconderlo.
È possibile impostare le seguenti opzioni:
Name | Description |
---|---|
Filter | You can select what constraint types will be listed. The types are All: allnn constraints Normal: constraints to normal sketch elements Datums: dimensional constraints to construction elements Named: constraints with a name Reference: constraints in reference mode |
Hide Internal Alignment | If checked, internal alignments will be hidden. Currently the sketcher uses internal alignments to construct Ellipses/Arcs and B-splines. Note: You can only hide these alignments in the constraint list. To hide them in the sketch you must use the toolbar button (Show/Hide internal geometry). |
Extended Information | If checked, extended information will be added to the list in this form [(GeoID1,PosID1);(GeoID2,PosID2);(GeoID3,PosID3)] PosID can have the following values: 0: Edge, 1 = starting point, 2 = endpoint, 3 = midpoint The GeoID is the number of the sketch element minus 1. The coordinate system origin has the GeoID -1. For example a dimension from the origin to the center of a circle with the element number '2' will get this information: [(1,3);(-1,1)] |
Elementi
Gli elementi dello schizzo sono elencati nelle sezioni e possono essere evidenziati. Se si fa clic su un elemento della lista esso viene evidenziato in verde. Ogni elemento nell'elenco inizia con un numero. Il numero è l'ordine di creazione nello schizzo.
Se si tiene premuto il tasto Ctrl è possibile selezionare più elementi contemporaneamente. Se si preme il tasto Z si può passare al successivo tipo valido. Ad esempio, se nell'elenco si seleziona una linea e si preme Z si può passare ai suoi punti di definizione.
È possibile impostare le seguenti opzioni:
Name | Description |
---|---|
Type | You can select the list selection type. If you set for example End point, all elements in the list that don't have an end point (circles etc.) will get the icon to indicate that you can click on them but they will not be highlighted. If you click e.g. on a line, its end point will be highlighted. You can choose between the types Edge, Starting Point, End Point and Center Point. |
Mode | You can select what sketch elements will be shown in the list, either All, Normal (regular sketch elements), Construction (construction elements) and External (elements from external geometries). |
Extended Naming | If checked, the naming in the list changes from <number>-type to type(Edge<number>[-Construction] So the name gets longer but contains the information about the element mode. |
Auto-switch to Edge | If checked, only the Type Edge will be available for the list. |
- General: Create sketch, Edit sketch, Map sketch to face, Reorient sketch, Validate sketch, Merge sketches, Mirror sketch, Leave sketch, View sketch, View section, Toggle grid, Toggle snap, Configure rendering order, Stop operation
- Sketcher geometries: Point, Line, Arc, Arc by 3 points, Circle, Circle by 3 points, Ellipse, Ellipse by 3 points, Arc of ellipse, Arc of hyperbola, Arc of parabola, B-spline by control points, Periodic B-spline by control points, B-spline by knots, Periodic B-spline by knots, Polyline, Rectangle, Centered rectangle, Rounded rectangle, Triangle, Square, Pentagon, Hexagon, Heptagon, Octagon, Regular polygon, Slot, Fillet, Corner-preserving fillet, Trim, Extend, Split, External geometry, Carbon copy, Toggle construction geometry
- Sketcher constraints:
- Geometric constraints: Coincident, Point on object, Vertical, Horizontal, Parallel, Perpendicular, Tangent, Equal, Symmetric, Block
- Dimensional constraints: Lock, Horizontal distance, Vertical distance, Distance, Radius or weight, Diameter, Auto radius/diameter, Angle, Refraction (Snell's law)
- Constraint tools: Toggle driving/reference constraint, Activate/deactivate constraint
- Sketcher tools: Select unconstrained DoF, Select associated constraints, Select associated geometry, Select redundant constraints, Select conflicting constraints, Show/hide internal geometry, Select origin, Select horizontal axis, Select vertical axis, Symmetry, Clone, Copy, Move, Rectangular array, Remove axes alignment, Delete all geometry, Delete all constraints
- Sketcher B-spline tools: Show/hide B-spline degree, Show/hide B-spline control polygon, Show/hide B-spline curvature comb, Show/hide B-spline knot multiplicity, Show/hide B-spline control point weight, Convert geometry to B-spline, Increase B-spline degree, Decrease B-spline degree, Increase knot multiplicity, Decrease knot multiplicity, Insert knot, Join curves
- Sketcher virtual space: Switch virtual space
- Additional: Sketcher Dialog, Preferences, Sketcher scripting
- Getting started
- Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
- Basics: About FreeCAD, Interface, Mouse navigation, Selection methods, Object name, Preferences, Workbenches, Document structure, Properties, Help FreeCAD, Donate
- Help: Tutorials, Video tutorials
- Workbenches: Std Base, Arch, Assembly, CAM, Draft, FEM, Inspection, Mesh, OpenSCAD, Part, PartDesign, Points, Reverse Engineering, Robot, Sketcher, Spreadsheet, Start, Surface, TechDraw, Test Framework, Web
- Hubs: User hub, Power users hub, Developer hub