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@ue-too/board / convertFromViewport2World

Function: convertFromViewport2World() ​

convertFromViewport2World(pointInViewport, cameraPositionInWorldSpace, cameraZoomLevel, cameraRotation, worldHasFlippedYAxis): Point

Defined in: packages/board/src/utils/coordinate-conversions/viewport-world.ts:50

Converts a point from viewport space to world space.

Parameters ​

pointInViewport ​

Point

The point in viewport coordinates to convert

cameraPositionInWorldSpace ​

Point

The camera's center position in world coordinates

cameraZoomLevel ​

number

The camera's zoom level (1.0 = normal, >1 = zoomed in, <1 = zoomed out)

cameraRotation ​

number

The camera's rotation angle in radians

worldHasFlippedYAxis ​

boolean = false

Whether world space uses inverted y-axis (default: false)

Returns ​

Point

The point in world coordinates

Remarks ​

This function applies the inverse of the camera transformation to convert from viewport coordinates to world coordinates. It's essential for translating user interactions (clicks, drags) into world-space positions.

The transformation applies these operations in reverse order:

  1. Unzoom: Divide by zoom level (world units per viewport pixel)
  2. Unrotate: Rotate by positive camera rotation (reverse the camera's rotation)
  3. Flip Y (if needed): Negate y if world uses mathematical coordinates
  4. Translate: Add camera position to get absolute world position

Mathematical formula:

worldPoint = rotate(pointInViewport / zoom, cameraRotation) + cameraPosition

Example ​

typescript
// Click at viewport center with zoomed and rotated camera
const viewportPoint = { x: 0, y: 0 };  // Center of viewport
const cameraPos = { x: 1000, y: 500 };
const zoom = 2.0;  // Zoomed in 2x
const rotation = Math.PI / 4;  // 45 degrees

const worldPoint = convertFromViewport2World(
  viewportPoint,
  cameraPos,
  zoom,
  rotation,
  false
);
// Result: { x: 1000, y: 500 } (camera position, since viewport center maps to camera position)

See ​

convertFromWorld2Viewport for inverse conversion