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public/sdk/three/jsm/utils/CameraUtils.js

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+import {
+	MathUtils,
+	Quaternion,
+	Vector3
+} from 'three';
+
+const _va = /*@__PURE__*/ new Vector3(), // from pe to pa
+	_vb = /*@__PURE__*/ new Vector3(), // from pe to pb
+	_vc = /*@__PURE__*/ new Vector3(), // from pe to pc
+	_vr = /*@__PURE__*/ new Vector3(), // right axis of screen
+	_vu = /*@__PURE__*/ new Vector3(), // up axis of screen
+	_vn = /*@__PURE__*/ new Vector3(), // normal vector of screen
+	_vec = /*@__PURE__*/ new Vector3(), // temporary vector
+	_quat = /*@__PURE__*/ new Quaternion(); // temporary quaternion
+
+
+/** Set a PerspectiveCamera's projectionMatrix and quaternion
+ * to exactly frame the corners of an arbitrary rectangle.
+ * NOTE: This function ignores the standard parameters;
+ * do not call updateProjectionMatrix() after this!
+ * @param {Vector3} bottomLeftCorner
+ * @param {Vector3} bottomRightCorner
+ * @param {Vector3} topLeftCorner
+ * @param {boolean} estimateViewFrustum */
+function frameCorners( camera, bottomLeftCorner, bottomRightCorner, topLeftCorner, estimateViewFrustum = false ) {
+
+	const pa = bottomLeftCorner, pb = bottomRightCorner, pc = topLeftCorner;
+	const pe = camera.position; // eye position
+	const n = camera.near; // distance of near clipping plane
+	const f = camera.far; //distance of far clipping plane
+
+	_vr.copy( pb ).sub( pa ).normalize();
+	_vu.copy( pc ).sub( pa ).normalize();
+	_vn.crossVectors( _vr, _vu ).normalize();
+
+	_va.copy( pa ).sub( pe ); // from pe to pa
+	_vb.copy( pb ).sub( pe ); // from pe to pb
+	_vc.copy( pc ).sub( pe ); // from pe to pc
+
+	const d = - _va.dot( _vn );	// distance from eye to screen
+	const l = _vr.dot( _va ) * n / d; // distance to left screen edge
+	const r = _vr.dot( _vb ) * n / d; // distance to right screen edge
+	const b = _vu.dot( _va ) * n / d; // distance to bottom screen edge
+	const t = _vu.dot( _vc ) * n / d; // distance to top screen edge
+
+	// Set the camera rotation to match the focal plane to the corners' plane
+	_quat.setFromUnitVectors( _vec.set( 0, 1, 0 ), _vu );
+	camera.quaternion.setFromUnitVectors( _vec.set( 0, 0, 1 ).applyQuaternion( _quat ), _vn ).multiply( _quat );
+
+	// Set the off-axis projection matrix to match the corners
+	camera.projectionMatrix.set( 2.0 * n / ( r - l ), 0.0,
+		( r + l ) / ( r - l ), 0.0, 0.0,
+		2.0 * n / ( t - b ),
+		( t + b ) / ( t - b ), 0.0, 0.0, 0.0,
+		( f + n ) / ( n - f ),
+		2.0 * f * n / ( n - f ), 0.0, 0.0, - 1.0, 0.0 );
+	camera.projectionMatrixInverse.copy( camera.projectionMatrix ).invert();
+
+	// FoV estimation to fix frustum culling
+	if ( estimateViewFrustum ) {
+
+		// Set fieldOfView to a conservative estimate
+		// to make frustum tall/wide enough to encompass it
+		camera.fov =
+			MathUtils.RAD2DEG / Math.min( 1.0, camera.aspect ) *
+			Math.atan( ( _vec.copy( pb ).sub( pa ).length() +
+							( _vec.copy( pc ).sub( pa ).length() ) ) / _va.length() );
+
+	}
+
+}
+
+export { frameCorners };