fix(rendering): actually suppress FBO resize-to-zero on minimize

[soloturn]

Fixes #5081 - game screen goes dark after minimizing (via a third-party minimize tool) and restoring.

This is #4980's fix, with an inverted condition

LwjglDisplayDevice.updateViewport already tries to guard against this - added by #4980 for an earlier report of the identical symptom - but the guard never actually worked.

GLFW reports the framebuffer as 0x0 while a window is minimized. DisplayResolutionDependentFbo.propertyChange and PerspectiveCamera's own DISPLAY_RESOLUTION_CHANGE listener both react to the event firing at all, not to its old/new values - propertyChange regenerates every resolution-dependent FBO at whatever size the display device reports at that moment. #4980's intent was to stop that event firing while minimized, using PropertyChangeSupport.firePropertyChange's own behaviour of skipping notification when old equals new as the switch:

boolean isMinimized = GLFW.glfwGetWindowAttrib(...) == GLFW.GLFW_TRUE;
int i = isMinimized ? 0 : 1;
propertyChangeSupport.firePropertyChange(DISPLAY_RESOLUTION_CHANGE, i, 1);

This picks the value backwards: while minimized, i=0 differs from newValue=1, so the event still fires - unchanged from before #4980 landed. While not minimized, i=1 matches newValue=1, so it's suppressed - a second, unrelated regression, since that's exactly when a resize should propagate.

Fix

Flip which value goes with which case: (1, 1) while minimized so the compare matches and nothing fires, (0, 1) otherwise so a genuine resize still does.

What I could and couldn't verify

Root-caused and fixed by reading, not reproduced - confirming this needs an actual Windows session with a real or synthetic minimize gesture, which I don't have here. The fix follows directly from documented GLFW behaviour (0x0 framebuffer while iconified) and PropertyChangeSupport's own equals-based suppression semantics, not from observing the bug happen.

No existing tests cover this class - updateViewport needs a live GLFW window/context, not something headless-testable. :engine:compileJava is clean.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 921fd2d1-05f7-474f-9eb1-c07a22fb5685

📥 Commits

Reviewing files that changed from the base of the PR and between 338d7dd and 89e9094.

📒 Files selected for processing (1)

• engine/src/main/java/org/terasology/engine/core/subsystem/lwjgl/LwjglDisplayDevice.java

Included review availability: Your plan provides up to 8 included reviews per hour; 6 remain after this review.

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📝 Walkthrough

Summary by CodeRabbit

• Bug Fixes
  • Corrected display resolution-change notifications during window resizing.
  • Resolution updates are now reported normally when the window is active and suppressed while minimized.

Walkthrough

updateViewport(int, int) now suppresses resolution-change notifications while the GLFW window is minimized. During normal resizing, it continues to send genuine property-change notifications.

Changes

Viewport notification handling

Layer / File(s)	Summary
Correct minimized-window notification handling engine/src/main/java/org/terasology/engine/core/subsystem/lwjgl/LwjglDisplayDevice.java	Minimized windows now receive equal old and new property values. Active resizing now receives different values and continues notifying listeners.

Estimated code review effort: 2 (Simple) | ~10 minutes

Merge Risk: ⚪ Minimal · up to 89e90

This localized rendering fix changes minimize-time framebuffer resize signaling so normal resizes continue to propagate; no actionable merge-blocking risk remains after normal checks and review.

Poem

A rabbit resized the viewport with care,
Kept minimized frames from stirring the air.
When windows grow wide, notifications hop,
FBOs stay steady when minimized clocks stop.
updateViewport now gets it just right.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly describes the fix that suppresses zero-size FBO resizing during window minimization.
Description check	✅ Passed	The description accurately explains the minimization bug, root cause, condition reversal, verification limits, and compilation result.
Linked Issues check	✅ Passed	The change addresses [#5081] by suppressing zero-size framebuffer resize events during minimization while preserving normal resize notifications.
Out of Scope Changes check	✅ Passed	The changes are limited to the viewport notification condition and directly support the linked issue objective.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch soloturn-fix-minimize-black-screen

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