ArtifactForms/MeshLibCore

package workspace;

import math.Mathf;
import math.Matrix3f;
import math.Matrix4f;
import math.Vector3f;
import processing.core.PApplet;
import processing.core.PMatrix;
import processing.event.KeyEvent;

public class FirstPersonView {

  private boolean enabled;

  private boolean left;

  private boolean right;

  private boolean forward;

  private boolean back;

  private boolean up;

  private boolean down;

  private float pitch = Mathf.PI;

  private float yaw = 0;

  private Vector3f eye = new Vector3f(-1000, 0, 1000);

  private float speed = 10;

  private PApplet context;

  public FirstPersonView(PApplet context) {
    this.context = context;
    context.registerMethod("pre", this);
    context.registerMethod("keyEvent", this);
  }

  public void pre() {
    if (!enabled) return;
    yaw = Mathf.map(context.mouseX, 0, context.width, Mathf.PI, -Mathf.PI);
    pitch = Mathf.map(context.mouseY, 0, context.height, -Mathf.PI, Mathf.PI);

    //        if (pitch > 89)
    //            pitch = 89;
    //        if (pitch < -89)
    //            pitch = -89;

    Vector3f front = new Vector3f();
    float x = Mathf.cos(Mathf.toRadians(yaw)) * Mathf.cos(Mathf.toRadians(pitch));
    float y = Mathf.sin(Mathf.toRadians(pitch));
    float z = Mathf.cos(Mathf.toRadians(yaw)) * Mathf.cos(Mathf.toRadians(pitch));
    front.set(x, y, z);

    Vector3f velocity = new Vector3f();

    if (left) {
      velocity.addLocal(-1, 0, 0);
    }

    if (right) {
      velocity.addLocal(1, 0, 0);
    }

    if (back) {
      velocity.addLocal(0, 0, 1);
    }

    if (forward) {
      velocity.addLocal(0, 0, -1);
    }

    velocity.multLocal(getRotationMatrix(yaw));

    eye.addLocal(velocity.mult(speed));
    eye.setY(-300);
  }

  public void apply() {
    Matrix4f m = Matrix4f.fpsViewRH(eye, pitch, yaw).transpose();
    PMatrix matrix = context.getMatrix();
    matrix.set(m.getValues());
    context.setMatrix(matrix);
  }

  public void keyEvent(KeyEvent key) {
    if (key.getAction() == KeyEvent.PRESS) onKeyPressed(key.getKey());
    if (key.getAction() == KeyEvent.RELEASE) onKeyReleased(key.getKey());
  }

  public void onKeyPressed(char key) {
    if (key == 'w' || key == 'W') forward = true;

    if (key == 's' || key == 'S') back = true;

    if (key == 'a' || key == 'A') left = true;

    if (key == 'd' || key == 'D') right = true;

    if (key == ' ') up = true;

    if (key == 'c' || key == 'C') down = true;
  }

  public void onKeyReleased(char key) {
    if (key == 'w' || key == 'W') forward = false;

    if (key == 's' || key == 'S') back = false;

    if (key == 'a' || key == 'A') left = false;

    if (key == 'd' || key == 'D') right = false;

    if (key == ' ') up = false;

    if (key == 'c' || key == 'C') down = false;
  }

  public Matrix3f getRotationMatrix(float angle) {
    Matrix3f m =
        new Matrix3f(
            Mathf.cos(angle), 0, Mathf.sin(angle), 0, 1, 0, -Mathf.sin(angle), 0, Mathf.cos(angle));
    return m;
  }

  public boolean isEnabled() {
    return enabled;
  }

  public void setEnabled(boolean enabled) {
    this.enabled = enabled;
  }
}