IllegalArgumentException in Camera.setFov()

[stephengold]

A crash that's easy to reproduce using FlyByCamera on a non-perspective camera in JMonkeyEngine v3.6.1-stable:

Oct 04, 2023 12:08:02 AM com.jme3.app.LegacyApplication handleError
SEVERE: Uncaught exception thrown in Thread[jME3 Main,5,main]
java.lang.IllegalArgumentException: Cannot set field of view on orthogonal camera
    at com.jme3.renderer.Camera.setFov(Camera.java:664)
    at com.jme3.input.FlyByCamera.zoomCamera(FlyByCamera.java:388)
    at com.jme3.input.FlyByCamera.onAnalog(FlyByCamera.java:467)
    at com.jme3.input.InputManager.invokeAnalogsAndActions(InputManager.java:285)
    at com.jme3.input.InputManager.onMouseMotionEventQueued(InputManager.java:412)
    at com.jme3.input.InputManager.processQueue(InputManager.java:869)
    at com.jme3.input.InputManager.update(InputManager.java:923)
    at com.jme3.app.LegacyApplication.update(LegacyApplication.java:785)
    at com.jme3.app.SimpleApplication.update(SimpleApplication.java:248)
    at com.jme3.system.lwjgl.LwjglWindow.runLoop(LwjglWindow.java:628)
    at com.jme3.system.lwjgl.LwjglWindow.run(LwjglWindow.java:717)
    at java.base/java.lang.Thread.run(Thread.java:829)

An easy fix would be for FlyByCamera to zoom only when the camera is in perspective mode. Another approach would be to implement zoom differently when the camera is in orthogonal mode.

[stephengold]

This might be related to PR #1492.

[stephengold]

I reproduced the issue in current "master" branch. Here's a minimal test app. Turning the scroll wheel on the mouse triggers the crash.

import com.jme3.app.SimpleApplication;

public class TestIssue2078 extends SimpleApplication {
    public static void main(String[] args) {
        new TestIssue2078().start();
    }

    @Override
    public void simpleInitApp() {
        cam.setParallelProjection(true);
    }
}

[stephengold]

I verified that this issue appeared between JME v3.3.2-stable and JME v3.4.0-stable . That's consistent with PR #1492 being the cause.