import { AbstractShaderNode } from '../core/AbstractShaderNode';
/**
 * A shader node that provides access to the normal matrix for transforming normal vectors
 * from local space to world space.
 *
 * The normal matrix is derived from the inverse transpose of the upper-left 3x3 portion
 * of the model matrix (world matrix). It ensures that normal vectors remain perpendicular
 * to surfaces after non-uniform scaling transformations. This matrix is essential for
 * proper lighting calculations in 3D rendering.
 *
 * The node operates in the vertex shader stage and supports both WebGL (GLSL) and
 * WebGPU (WGSL) rendering backends.
 *
 * @example
 * ```typescript
 * const normalMatrixNode = new NormalMatrixShaderNode();
 * // Connect to other shader nodes that require normal transformation
 * const normalMatrixOutput = normalMatrixNode.getOutput('outValue');
 * ```
 */
export declare class NormalMatrixShaderNode extends AbstractShaderNode {
    /**
     * Creates a new NormalMatrixShaderNode instance.
     *
     * Initializes the shader node with vertex stage shader code for both GLSL and WGSL,
     * and sets up a Mat3 float output socket for the normal transformation matrix.
     * The output matrix can be used to transform normal vectors from local space to world space
     * while preserving their geometric properties under non-uniform transformations.
     *
     * The node automatically retrieves the normal matrix from the rendering system's
     * uniform buffer based on the current instance ID.
     */
    constructor();
}