ArtifactForms/MeshLibCore

package mesh.modifier;

import math.Vector3f;
import mesh.Mesh3D;

/**
 * TranslateModifier applies a translation (offset) to all vertices of a given
 * 3D mesh.
 * 
 * This modifier translates each vertex in the provided mesh by a given 3D
 * vector (delta). The operation can be performed efficiently in parallel using
 * Java's parallel streams for improved performance on large meshes.
 */
public class TranslateModifier implements IMeshModifier {

    /**
     * The translation vector representing the offset in 3D space.
     */
    private Vector3f delta;

    /**
     * Default constructor initializes translation delta to (0, 0, 0).
     */
    public TranslateModifier() {
        this.delta = new Vector3f(0, 0, 0);
    }

    /**
     * Constructs a TranslateModifier with specified translation offsets along
     * each axis.
     *
     * @param deltaX Offset along the X-axis.
     * @param deltaY Offset along the Y-axis.
     * @param deltaZ Offset along the Z-axis.
     */
    public TranslateModifier(float deltaX, float deltaY, float deltaZ) {
        this.delta = new Vector3f(deltaX, deltaY, deltaZ);
    }

    /**
     * Constructs a TranslateModifier using a Vector3f for the specified
     * translation delta.
     *
     * @param delta The 3D translation vector to apply to the mesh's vertices.
     * @throws IllegalArgumentException if the provided delta is null.
     */
    public TranslateModifier(Vector3f delta) {
        if (delta == null) {
            throw new IllegalArgumentException("Delta cannot be null.");
        }
        this.delta = new Vector3f(delta);
    }

    /**
     * Applies the translation to all vertices in the provided mesh by adding the
     * delta vector to each vertex. Uses parallel processing for efficiency.
     * 
     * If the provided mesh contains no vertices, the method safely returns the
     * mesh without changes.
     * 
     * @param mesh The 3D mesh whose vertices will be translated.
     * @return The modified 3D mesh after applying the translation.
     * @throws IllegalArgumentException if the provided mesh is null.
     */
    @Override
    public Mesh3D modify(Mesh3D mesh) {
        if (mesh == null) {
            throw new IllegalArgumentException("Mesh cannot be null.");
        }
        if (!mesh.vertices.isEmpty()) {
            mesh.vertices.parallelStream().forEach(vertex -> vertex.addLocal(delta));
        }
        return mesh;
    }

    /**
     * Sets the translation of this modifiers delta to the values provided by the
     * new delta.
     *
     * @param delta The new delta.
     * @throws IllegalArgumentException if the provided delta is null.
     */
    public void setDelta(Vector3f delta) {
        if (delta == null) {
            throw new IllegalArgumentException("Delta cannot be null.");
        }
        this.delta.set(delta);
    }

    /**
     * Retrieves the translation offset along the X-axis.
     *
     * @return The X component of the translation delta.
     */
    public float getDeltaX() {
        return delta.x;
    }

    /**
     * Retrieves the translation offset along the Y-axis.
     *
     * @return The Y component of the translation delta.
     */
    public float getDeltaY() {
        return delta.y;
    }

    /**
     * Retrieves the translation offset along the Z-axis.
     *
     * @return The Z component of the translation delta.
     */
    public float getDeltaZ() {
        return delta.z;
    }

}