@ue-too/board / index / cameraPositionToGet

関数: cameraPositionToGet()

cameraPositionToGet(pointInWorld, toPointInViewPort, cameraZoomLevel, cameraRotation): Point

定義: packages/board/src/camera/utils/coordinate-conversion.ts:468

Calculates the camera position needed to place a world point at a specific viewport location. Useful for implementing "zoom to point" or "focus on object" features.

パラメータ

pointInWorld

Point

The world point to focus on

toPointInViewPort

Point

Where in the viewport this point should appear (origin at center)

cameraZoomLevel

number

Target zoom level

cameraRotation

number

Target rotation in radians

戻り値

Point

Camera position that achieves the desired framing

Remarks

This is particularly useful for:

• Zoom-to-cursor: Make clicked point stay under cursor while zooming
• Pan-and-zoom: Smoothly navigate to show a specific object
• Focus features: Center camera on a world object

The viewport point is in viewport coordinates (center origin). To center on a world point, use toPointInViewPort = {x: 0, y: 0}.

例

// Center camera on world point (1000, 500)
const newCameraPos = cameraPositionToGet(
  { x: 1000, y: 500 },  // world point to focus on
  { x: 0, y: 0 },        // center of viewport
  2.0,                   // zoom level
  0                      // rotation
);
camera.setPosition(newCameraPos);

// Zoom to cursor position
// Keep world point under cursor at (viewportX, viewportY)
const cursorViewport = {
  x: mouseX - canvas.width/2,
  y: mouseY - canvas.height/2
};
const worldAtCursor = camera.convertFromViewPort2WorldSpace(cursorViewport);
const newPos = cameraPositionToGet(worldAtCursor, cursorViewport, newZoom, rotation);
camera.setPosition(newPos);
camera.setZoomLevel(newZoom);