Struct DiskWidget 

pub struct DiskWidget {
    pub center: Vec3,
    pub normal: Vec3,
    pub radius: f32,
    pub color: [f32; 4],
    pub handle_color: [f32; 4],
    pub normal_display_length: f32,
    /* private fields */
}

An interactive disk widget: a bounded circular plane with center, normal, and radius.

Three handles: center (moves freely), normal tip (orbits the normal), and a radius handle on the disk rim (scales the radius).

Usage

let mut disk = DiskWidget::new(glam::Vec3::ZERO, glam::Vec3::Z, 2.0);

// Each frame:
disk.update(&ctx);
fd.scene.polylines.push(disk.wireframe_item(DISK_ID));
fd.scene.glyphs.push(disk.handle_glyphs(HANDLE_ID, &ctx));

Fields

center: Vec3

World-space center of the disk.

normal: Vec3

Unit normal vector of the disk plane.

radius: f32

Radius in world units.

color: [f32; 4]

RGBA color for the wireframe circle and normal line.

handle_color: [f32; 4]

RGBA color for the drag handles. Non-zero alpha overrides LUT coloring.

normal_display_length: f32

Distance from center to the normal-tip handle sphere.

Implementations

impl DiskWidget

pub fn new(center: Vec3, normal: Vec3, radius: f32) -> Self

Create a new disk widget.

normal is normalized internally; if zero, defaults to Vec3::Z.

pub fn is_active(&self) -> bool

True while a drag is in progress on any handle.

pub fn update(&mut self, ctx: &WidgetContext) -> WidgetResult

Process input for this frame. Returns Updated if state changed.

pub fn wireframe_item(&self, id: u64) -> PolylineItem

Build a PolylineItem for the wireframe circle and normal indicator.

The circle uses 32 segments. A line from center to the normal tip is also included.

pub fn handle_glyphs(&self, id_base: u64, ctx: &WidgetContext) -> GlyphItem

Build a GlyphItem with three sphere handles: center, normal tip, and radius edge.

id_base = center, id_base + 1 = normal tip, id_base + 2 = radius handle.