Sketcher ConstrainAngle/fr

Description
La Contrainte Angle est une Donnée de Contrainte destinée à fixer les angles sur le croquis. Elle est capable de fixer des pentes de lignes individuelles, les angles entre les lignes, les angles des intersections de courbes, et l'espace d'angles d'arcs circulaires

Comment l'utiliser
La contrainte peut être appliquée de 4 manières différentes:
 * 1) pour des lignes individuelles
 * 2) entre des lignes
 * 3) pour des intersections de courbes
 * 4) pour des arcs de cercles

Pour appliquer la contrainte d'angle, il faut suivre les étapes:
 * Sélectionnez une, deux ou trois entités dans l'esquisse. Le mode sera choisi en fonction de la sélection.
 * Appelez la contrainte en cliquant sur son icône sur la barre d'outils, ou en sélectionnant l'option de menu, ou en utilisant le raccourci clavier. Une boîte de dialogue d'édition de donnée apparaît.
 * Modifier l'angle si nécessaire. L'angle peut être saisie comme une expression qui sera évaluée et le résultat sera stocké. Cliquez sur OK.

As with any datum constraint, it is possible to change the angle value later by double-clicking the constraint in constraint list or 3d view. Entering a negative value will cause the angle direction to flip.

line slope angle
Accepted selection: line



The constraint sets the polar angle of line's direction. It is the angle between the line and X axis of the sketch.

arc span (v0.15)
Accepted selection: arc of circle



In this mode, the constraint fixes angular span of a circular arc.

between lines
Accepted selection: line +  line



In this mode, the constraint sets the angle between two lines. It is not required that the lines intersect.

between curves at intersection (angle-via-point) (v0.15)
Accepted selection: any line/curve +  any line/curve  +  any point



In this mode, angle between two curves is constrained at the point of their intersection. The intersection point can be on curves' extensions. The point should be specified explicitly, since curves typically intersect in more than one point.

For the constraint to work correctly, the point must be on both curves. So, as the constraint is invoked, the point will be automatically constrained onto both curves (helper constraints will be added, if necessary), and the angle between curves will be constrained at the point. These helper constraints are plain regular constraints. They can be added manually, or deleted. There are no helper constraints on the example picture above, because the point selected is already the intersection of curves.

Scripting
Angle Constraint can be created from macros and from the python console by using the following:

where:
 * Sketch is a sketch object
 * iline, iline1, iline2 are integers specifying the lines by their ordinal numbers in Sketch.
 * pointpos1, pointpos2 should be 1 for start point and 2 for end point. The choice of endpoints allows to set internal angle (or external), and it affects how the constraint is drawn on the screen.
 * geoidpoint and pointpos in AngleViaPoint are the indexes specifying the point of intersection.
 * angle is the angle value in radians. The angle is counted between tangent vectors in counterclockwise direction. Tangent vectors are pointing from start to end for the lines (or vice versa if ending point is supplied in angle between lines mode), and along counterclockwise direction for circles, arcs and ellipses. Quantity is also accepted as an angle (e.g. App.Units.Quantity('45 deg'))