MAINT-6786 scale gets out of bonds and causes crash

1 files changed, 23 insertions, 6 deletions

diff --git a/indra/newview/llviewerwindow.cpp b/indra/newview/llviewerwindow.cpp
index 9679f69e2c..4f4b33fa8c 100644
--- a/indra/newview/llviewerwindow.cpp
+++ b/indra/newview/llviewerwindow.cpp
@@ -251,6 +251,11 @@ BOOL				gDisplayBadge = FALSE;
 static const U8 NO_FACE = 255;
 BOOL gQuietSnapshot = FALSE;
 
+// Minimum value for UIScaleFactor, also defined in preferences, ui_scale_slider
+static const F32 MIN_UI_SCALE = 0.75f;
+// 2.0 in preferences, but win10 supports larger scaling and value is used more as
+// sanity check, so leaving space for larger values from DPI updates.
+static const F32 MAX_UI_SCALE = 7.0f;
 static const F32 MIN_DISPLAY_SCALE = 0.75f;
 
 std::string	LLViewerWindow::sSnapshotBaseName;
@@ -1595,9 +1600,16 @@ BOOL LLViewerWindow::handleDeviceChange(LLWindow *window)
 
 void LLViewerWindow::handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height)
 {
-    gSavedSettings.setF32("UIScaleFactor", ui_scale_factor);
-    LLViewerWindow::reshape(window_width, window_height);
-    mResDirty = true;
+    if (ui_scale_factor >= MIN_UI_SCALE && ui_scale_factor <= MAX_UI_SCALE)
+    {
+        gSavedSettings.setF32("UIScaleFactor", ui_scale_factor);
+        LLViewerWindow::reshape(window_width, window_height);
+        mResDirty = true;
+    }
+    else
+    {
+        LL_WARNS() << "DPI change caused UI scale to go out of bounds: " << ui_scale_factor << LL_ENDL;
+    }
 }
 
 void LLViewerWindow::handlePingWatchdog(LLWindow *window, const char * msg)
@@ -1753,6 +1765,11 @@ LLViewerWindow::LLViewerWindow(const Params& p)
 
 
 	F32 system_scale_factor = mWindow->getSystemUISize();
+	if (system_scale_factor < MIN_UI_SCALE || system_scale_factor > MAX_UI_SCALE)
+	{
+		// reset to default;
+		system_scale_factor = 1.f;
+	}
 	if (p.first_run || gSavedSettings.getF32("LastSystemUIScaleFactor") != system_scale_factor)
 	{
 		mSystemUIScaleFactorChanged = !p.first_run;
@@ -1763,7 +1780,7 @@ LLViewerWindow::LLViewerWindow(const Params& p)
 
 	// Get the real window rect the window was created with (since there are various OS-dependent reasons why
 	// the size of a window or fullscreen context may have been adjusted slightly...)
-	F32 ui_scale_factor = gSavedSettings.getF32("UIScaleFactor");
+	F32 ui_scale_factor = llclamp(gSavedSettings.getF32("UIScaleFactor"), MIN_UI_SCALE, MAX_UI_SCALE);
 	
 	mDisplayScale.setVec(llmax(1.f / mWindow->getPixelAspectRatio(), 1.f), llmax(mWindow->getPixelAspectRatio(), 1.f));
 	mDisplayScale *= ui_scale_factor;
@@ -5251,7 +5268,7 @@ F32	LLViewerWindow::getWorldViewAspectRatio() const
 
 void LLViewerWindow::calcDisplayScale()
 {
-	F32 ui_scale_factor = gSavedSettings.getF32("UIScaleFactor");
+	F32 ui_scale_factor = llclamp(gSavedSettings.getF32("UIScaleFactor"), MIN_UI_SCALE, MAX_UI_SCALE);
 	LLVector2 display_scale;
 	display_scale.setVec(llmax(1.f / mWindow->getPixelAspectRatio(), 1.f), llmax(mWindow->getPixelAspectRatio(), 1.f));
 	display_scale *= ui_scale_factor;
@@ -5264,7 +5281,7 @@ void LLViewerWindow::calcDisplayScale()
 	
 	if (display_scale != mDisplayScale)
 	{
-		LL_INFOS() << "Setting display scale to " << display_scale << LL_ENDL;
+		LL_INFOS() << "Setting display scale to " << display_scale << " for ui scale: " << ui_scale_factor << LL_ENDL;
 
 		mDisplayScale = display_scale;
 		// Init default fonts