CATROID-1646 Restore full-resolution session screenshots for visual placement

[wslany]

Visual placement uses the saved stage screenshot as its background image. Since #4852, that screenshot has been reduced to thumbnail resolution before being written, which makes thin pen/plot/cut/engrave lines disappear or look fuzzy in visual placement.

https://catrobat.atlassian.net/browse/CATROID-1646

This PR keeps the persisted screenshot thumbnail-sized so project storage and exported .catrobat files stay small, but also writes a full-resolution screenshot to app cache for the current session. Visual placement now prefers that session-local cache image.

It also adds a regression test that verifies the intended split:

• persisted project/scene screenshots stay low-resolution
• session-local screenshots keep the original framebuffer size for visual placement

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[Copilot]

Pull request overview

Restores full-resolution stage screenshots for visual placement by writing an additional session-local screenshot into the app cache while keeping persisted project/scene screenshots thumbnail-sized to avoid inflating project storage and exports.

Changes:

• Added a session screenshot cache path and made visual placement background loading prefer session-local full-res screenshots.
• Updated screenshot saving to write both persisted thumbnail screenshots and an extra full-resolution session screenshot to cache.
• Added an Android regression test verifying persisted screenshots remain low-res while session-local cache screenshots keep framebuffer resolution.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
catroid/src/main/java/org/catrobat/catroid/utils/ProjectManagerExtensions.kt	Adds session screenshot file resolution and preference logic in getProjectBitmap().
catroid/src/main/java/org/catrobat/catroid/stage/ScreenshotSaver.kt	Writes an additional full-resolution screenshot to cache and refactors bitmap saving into a helper.
catroid/src/androidTest/java/org/catrobat/catroid/test/stage/ScreenshotSaverResolutionRegressionTest.kt	Adds regression coverage for persisted-vs-session screenshot resolution behavior.

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[wslany]

Addressed the SonarCloud reliability finding from the latest Quality Gate failure in 20302ef17e8d6696a4353ddff08e22c3c67a16ea.

The issue was the ignored boolean return value of file.delete() in ScreenshotSaver.saveBitmap(). The code now checks the delete result explicitly and logs when cleanup of an incomplete screenshot file fails before throwing the IOException.

Local verification:

• :catroid:compileCatroidDebugKotlin
• :catroid:compileCatroidDebugJavaWithJavac
• :catroid:compileCatroidDebugAndroidTestKotlin

[harshsomankar123-tech]

Thanks! @wslany for the changes .
I re-ran the new instrumentation test on the current PR head. It currently fails before the assertions run because StageActivity is auto-launched without a prepared current project/scene, so setUp() dereferences projectManager.currentlyPlayingScene while it is null. tearDown() then adds a secondary lateinit failure, and LibGDX teardown can also crash afterward.

'void com.badlogic.gdx.backends.android.keyboardheight.KeyboardHeightProvider.close()'
on a null object reference
at com.badlogic.gdx.backends.android.AndroidApplication.onDestroy()

It seems the activity can end up only partially initialized in the test environment, leading to a crash before the screenshot assertions complete. This doesn’t appear related to the screenshot logic itself, but it does mean the regression test is currently not passing as an instrumented test on my setup.
Please Take A Look and solve it.

[wslany]

@harshsomankar123-tech Thanks again for catching the test-harness failure.

I addressed it in 8d6b148e50cc9b48d3f267202fd1acebc9840b85. The regression test no longer auto-launches StageActivity; it now prepares its own test project/current scene/current playing scene and uses the application context for DefaultAndroidFiles. tearDown() is also guarded so a partial setup cannot cause the secondary lateinit failure. This removes the partially initialized StageActivity/LibGDX teardown path from this regression test and keeps it focused on ScreenshotSaver plus getProjectBitmap() behavior.

Local emulator verification now passes on Medium_Phone_API_35 / emulator-5554:

adb shell am instrument -w -r -e class org.catrobat.catroid.test.stage.ScreenshotSaverResolutionRegressionTest org.catrobat.catroid.test/org.catrobat.catroid.runner.UiTestApplicationRunner

Time: 5.611
OK (3 tests)

I also rebuilt and installed the app/test APKs locally before running the instrumentation command:

./gradlew.bat :catroid:assembleCatroidDebug :catroid:assembleCatroidDebugAndroidTest --no-daemon --console=plain
BUILD SUCCESSFUL

[harshsomankar123-tech]

@wslany Thanks! LGTM

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[urkat]

LGTM