Struct ViewportState 

pub struct ViewportState {
    pub zoom: f32,
    pub pan: Vec2,
    pub mode: ViewportMode,
    pub image_size: Vec2,
    pub viewport_size: Vec2,
    pub scrubber: ViewportScrubber,
    pub rmb_tool_drag_active: bool,
    pub last_rendered_epoch: u64,
    pub last_rendered_frame: Option<i32>,
}

Viewport state for pan/zoom

Fields

zoom: f32

pan: Vec2

mode: ViewportMode

image_size: Vec2

viewport_size: Vec2

scrubber: ViewportScrubber

rmb_tool_drag_active: bool

True while RMB tool drag is active (latched on press inside viewport). Used by viewport UI to implement “no-aim” transform drags without relying on hover_pos, which may be None during drags depending on platform/backend.

last_rendered_epoch: u64

Last rendered cache epoch (0 = needs refresh)

last_rendered_frame: Option<i32>

Last rendered frame number (for detecting frame changes)

Implementations

impl ViewportState

pub fn new() -> Self

pub fn reset(&mut self)

Reset viewport to default zoom and pan

pub fn request_refresh(&mut self)

Request viewport to refresh current frame (resets tracking to force re-render)

pub fn draw(&self, ui: &Ui, panel_rect: Rect)

Draw all viewport overlays (scrubber, guides, safe zones, etc.)

pub fn set_viewport_size(&mut self, size: Vec2)

Update viewport size (called when window resizes)

pub fn set_image_size(&mut self, size: Vec2)

Update image size (called when new image loads)

pub fn set_mode_fit(&mut self)

Set AutoFit mode and apply fit

pub fn set_mode_100(&mut self)

Set Auto100 mode and apply 100% zoom

pub fn handle_zoom(&mut self, zoom_delta: f32, cursor_pos: Vec2)

Handle zoom with center-on-cursor (switches to Manual mode)

pub fn handle_pan(&mut self, delta: Vec2)

Handle pan (switches to Manual mode)

pub fn get_image_screen_bounds(&self) -> Rect

Get image bounds in screen space

pub fn is_point_over_image(&self, screen_pos: Vec2) -> bool

Check if screen position is over the image

pub fn image_to_screen(&self, image_pos: Vec2) -> Vec2

Convert image space coordinates (0..image_size) to screen space. Uses frame space (centered, pixel coords) as intermediate — matches space.rs.

pub fn screen_to_image(&self, screen_pos: Vec2) -> Option<Vec2>

Convert screen space coordinates to image space (0..image_size). Returns None if position is outside the image bounds.

pub fn handle_scrubbing( &mut self, response: &Response, panel_rect: Rect, double_clicked: bool, play_start: i32, play_end: i32, ) -> Option<i32>

High-level scrubbing handler. Returns Some(frame_idx) when scrubbing requests a new frame, or None if nothing changed. Maps mouse X from image bounds directly to [play_start, play_end] frame range.

Coordinate System

• panel_rect is in screen coordinates (absolute)
• response.interact_pointer_pos() returns screen coordinates
• get_image_screen_bounds() returns local coordinates (relative to viewport panel)

We convert mouse_pos to local coords by subtracting panel_rect.min.

pub fn render_state(&self) -> ViewportRenderState

Snapshot render-only matrices for GL callbacks.

pub fn get_model_matrix(&self) -> [[f32; 4]; 4]

Get model matrix for shader (scales normalized quad to image pixel size).

pub fn get_view_matrix(&self) -> [[f32; 4]; 4]

Get view matrix for shader (zoom + pan only, matches gizmo).

pub fn get_projection_matrix(&self) -> [[f32; 4]; 4]

Get orthographic projection matrix for shader

Trait Implementations

impl Clone for ViewportState

fn clone(&self) -> ViewportState

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Default for ViewportState

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ViewportState

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ViewportState

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.