Struct kiss3d_trackball::Trackball

pub struct Trackball {
    pub input: Input<f32>,
    pub clamp: Clamp<f32>,
    pub frame: Frame<f32>,
    pub reset: Frame<f32>,
    pub scene: Scene<f32>,
    // some fields omitted
}

Trackball camera mode.

A trackball camera is a camera working similarly like a trackball device. The camera eye is orbited around its target, the trackball’s center, and always looking at it. This implementation is split into several members defined by the trackball crate categorizing all the methods to control the different aspects of a camera.

Camera Controls

Following default controls are defined which are customizable via Self::input:

Mouse	Touch	Action
Left Button Press + Drag	One-Finger + Drag	Orbits eye around target.
⮱ but at trackball’s border	Two-Finger + Roll	Purely rolls eye about view direction.
Right Button Press + Drag	Two-Finger + Drag	Slides trackball along focus plane.
Scroll In/Out	Two-Finger + Pinch Out/In	Scales distance zooming in/out.
Left Button Press + Release	Any-Finger + Release	Slides to cursor/finger position.

Key	Action
O	Switches between orthographic and perspective projection.
Enter	Resets camera eye and target to Self::reset.

Camera Alignment

Realign camera via Self::frame and define user boundary conditions via Self::clamp like minimum and maximum target distance from camera eye. Optionally, update the alignment to reset to when pressing Input::reset_key() via Self::reset.

Camera Projection

Adjust camera projection via Self::scene like setting field of view or clip plane distances.

Fields

input: Input<f32>

Input keys/buttons and their modifiers.

clamp: Clamp<f32>

Clamp as user boundary conditions of Frame.

frame: Frame<f32>

Frame wrt camera eye and target.

reset: Frame<f32>

Reset frame wrt camera eye and target.

scene: Scene<f32>

Scene wrt enclosing viewing frustum.

Implementations

impl Trackball

pub fn new(eye: &Point3<f32>, at: &Point3<f32>, up: &Vector3<f32>) -> Trackball

Creates camera with eye position inclusive its roll attitude and target position.

Default frustum has field of view of π/4 with near and far clip planes at 1E-1 and 1E+6.

pub fn new_with_frustum(
    fov: f32,
    znear: f32,
    zfar: f32,
    eye: &Point3<f32>,
    at: &Point3<f32>,
    up: &Vector3<f32>
) -> Trackball

Like Self::new() but with custom frustum.

Trait Implementations

impl Camera for Trackball

fn clip_planes(&self) -> (f32, f32)

The clipping planes, aka. (znear, zfar).

fn view_transform(&self) -> Isometry3<f32>

The camera view transform.

fn eye(&self) -> Point3<f32>

The camera position.

fn handle_event(&mut self, canvas: &Canvas, event: &WindowEvent)

Handle a mouse event.

fn upload(
    &self,
    _: usize,
    proj: &mut ShaderUniform<Matrix4<f32>>,
    view: &mut ShaderUniform<Matrix4<f32>>
)

Upload the camera view and projection to the gpu. This can be called multiple times on the render loop.

fn transformation(&self) -> Matrix4<f32>

The transformation applied by the camera to transform a point in world coordinates to a point in device coordinates.

fn inverse_transformation(&self) -> Matrix4<f32>

The transformation applied by the camera to transform point in device coordinates to a point in world coordinate.

fn update(&mut self, _: &Canvas)

Update the camera. This is called once at the beginning of the render loop.

pub fn num_passes(&self) -> usize

The number of passes required by this camera.

pub fn start_pass(&self, _pass: usize, _canvas: &Canvas)

Indicates that a pass will begin.

pub fn render_complete(&self, _canvas: &Canvas)

Indicates that the scene has been rendered and the post-processing is being run.

pub fn project(
    &self,
    world_coord: &Point<f32, U3>,
    size: &Matrix<f32, U2, U1, <DefaultAllocator as Allocator<f32, U2, U1>>::Buffer>
) -> Matrix<f32, U2, U1, <DefaultAllocator as Allocator<f32, U2, U1>>::Buffer>

Converts a 3d point to 2d screen coordinates, assuming the screen has the size size.

pub fn unproject(
    &self,
    window_coord: &Point<f32, U2>,
    size: &Matrix<f32, U2, U1, <DefaultAllocator as Allocator<f32, U2, U1>>::Buffer>
) -> (Point<f32, U3>, Matrix<f32, U3, U1, <DefaultAllocator as Allocator<f32, U3, U1>>::Buffer>)

Converts a point in 2d screen coordinates to a ray (a 3d position and a direction).

impl Clone for Trackball

fn clone(&self) -> Trackball

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.