export declare const check_picking_alpha = "\nfloat viewZ = depthToViewZ(uIsOrtho, fragmentDepth, uNear, uFar);\nfloat fogFactor = smoothstep(uFogNear, uFogFar, abs(viewZ));\nfloat alpha = (1.0 - fogFactor) * uAlpha;\nif (uAlpha < uPickingAlphaThreshold || alpha < 0.1)\n    discard; // ignore so the element below can be picked\n";