SnapContext

Remarks

Doc 24's D4, and it is a context rather than a settings bag for one reason. Snapping attached to the gizmo is a vertex snap that works when you drag an object and not when you extrude a face, which reads as the feature being broken rather than as two features. TransformGizmo, ScenePlacement and every blockout tool take the same instance, so there is one answer to "am I snapping" and one place it is written.

Three orthogonal parts, which is Blender's arrangement and the reason its snapping is the one people miss: Elements is what you land on, Base is what of yours lands on it, and Modifiers is everything that is true of a snap without being either.

⚠ The four booleans and three steps that were here before are still here, and still mean what they meant. They are views over Elements rather than separate state — two writers for one fact is how a toolbar toggle and a settings panel end up disagreeing — so everything that reads SnapPosition or SnapToVertex is unchanged, and everything that writes them moves the set.

Snapping rounds the total of a drag, not each step of it. Rounding each frame's delta accumulates the rounding error, so a slow drag across ten grid squares lands somewhere between two of them and a fast one lands on a line. Every implementation gets this wrong once.

The steps are separate numbers because they are separate decisions: a level built on a quarter-metre grid still wants fifteen-degree rotations.

Fields and properties (15)

• public SnapElements Elements

  What a position may land on.

• public SnapBase Base

  Which part of what is being dragged is put on it.

• public SnapModifiers Modifiers

  The orthogonal switches.

• public bool SnapPosition

  Whether a translate moves by whole steps of GridStep.

• public bool AbsoluteGrid

  Whether a translate lands on the world grid rather than moving by whole steps of it.

• public bool SnapToVertex

  Whether a drag lands on the nearest vertex of what is under the pointer.

• public bool SnapToSurface

  Whether a drop or a drag lands on the surface under the pointer.

• public bool SnapRotation

  Whether a rotate rounds to AngleStep.

• public bool SnapScale

  Whether a scale rounds to ScaleStep.

• public WorkPlane? Plane

  The plane whose step this follows, or for a step of its own.

• public float GridStep

  How far apart the grid lines are, in world units.

• public float AngleStep

  How far one rotation step is, in degrees.

• public float ScaleStep

  How far one scale step is, as a factor.

• public float VertexRadius

  How near an element has to be to be snapped to, in render pixels.

• public bool SnapsToGeometry

  Whether any element needing geometry under the pointer is on.

Methods (8)

• public bool Has(SnapElements element)

  Whether an element is on.

• public bool Is(SnapModifiers modifier)

  Whether a modifier is on.

• public void Toggle(SnapElements element, bool on)

  Turns an element on or off.

• public void Toggle(SnapModifiers modifier, bool on)

  Turns a modifier on or off.

• public float Position(float value)

  Rounds a distance to the grid, if position snapping is on.

• public Vector3 Position(Vector3 value)

  Rounds an offset to the grid, component by component.

• public float Rotation(float radians)

  Rounds an angle in radians to the angle step, if rotation snapping is on.

• public float Scale(float factor)

  Rounds a scale factor, if scale snapping is on.

Used by (16)

• EditorApplicationVixen.Editor.App
• GizmoTestsVixen.Editor.SceneView.Tests
• ISceneProbeVixen.Editor.SceneView
• PrecisionTestsVixen.Editor.SceneView.Tests
• ScenePlacementVixen.Editor.SceneView
• SceneProbeVixen.Editor.SceneView
• SceneTestsVixen.Editor.SceneView.Tests
• SceneViewportVixen.Editor.SceneView
• SnapCommandTestsVixen.Editor.App.Tests
• SnapContextTestsVixen.Editor.SceneView.Tests
• SnapTestsVixen.Editor.SceneView.Tests
• SplineEditVixen.Editor.SceneView
• SplineEditTestsVixen.Editor.SceneView.Tests
• TransformGizmoVixen.Editor.SceneView
• WorkPlaneCommandTestsVixen.Editor.App.Tests
• WorkPlaneTestsVixen.Editor.SceneView.Tests