Preserving angles of graph elbows

摘要

Techniques are provided for preserving angles at graph elbows as graph nodes are moved. A graph, which includes a first segment and a second segment that form an acute or obtuse angle at a vertex, is displayed. The first segment has a first end opposite the vertex at a first position; the second segment has a second end opposite the vertex at a second position. User input moves the second end from the second position to a third position. In response, the angle is automatically preserved by modifying a length of the first segment and a length of the second segment, without modifying the first position of the first end. Other techniques can replace two segments with a single segment if one of the segments becomes too short, or snap an elbow angle to a specified angle if moving the node causes the elbow angle to near the specified angle.

主权项

1. A process comprising:
one or more computing devices causing, on a computer display device, display of a graph comprising a first segment and a second segment, wherein the first segment and the second segment form an acute or obtuse angle at a vertex, wherein the first segment comprises a first end opposite the vertex at a first position on the graph, and wherein the second segment comprises a second end opposite the vertex at a second position on the graph; the one or more computing devices receiving input that moves the second end from the second position to a third position on the graph; in response to the input, the one or more computing devices automatically preserving the acute or obtuse angle by modifying a length of the first segment and a length of the second segment, and modifying the first segment by mirroring the first segment over a vertical axis or a horizontal axis; wherein the one or more computing devices automatically preserve the acute or obtuse angle by swapping an interior angle formed by the first position, the vertex, and the second position for an exterior angle, supplementary to the interior angle, formed by the first segment, the vertex, and the third position.