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@ue-too/board / index / minZoomLevelBaseOnWidth

函式: minZoomLevelBaseOnWidth()

minZoomLevelBaseOnWidth(boundaries, canvasWidth, canvasHeight, cameraRotation): number | undefined

定義於: packages/board/src/utils/zoomlevel-adjustment.ts:202

Calculates minimum zoom level based only on boundary width.

參數

boundaries

The world-space boundaries

Boundaries | undefined

canvasWidth

number

Canvas width in pixels

canvasHeight

number

Canvas height in pixels

cameraRotation

number

Camera rotation angle in radians

回傳

number | undefined

Minimum zoom level, or undefined if width is not defined

備註

Similar to minZoomLevelBaseOnDimensions but only considers the width constraint. Useful when height is unbounded or not relevant.

Calculates zoom needed to fit the boundary width within the canvas, accounting for rotation:

  • Width projection on canvas X-axis: width * cos(rotation)
  • Width projection on canvas Y-axis: width * sin(rotation)

Takes the maximum of these to ensure the width fits regardless of how rotation distributes it across canvas axes.

範例

typescript
const boundaries = {
  min: { x: 0 },
  max: { x: 1000 }
};

const zoom = minZoomLevelBaseOnWidth(boundaries, 800, 600, 0);
// Result: 0.8 (800/1000)

參閱

minZoomLevelBaseOnDimensions for full calculation