WebView: withMinimumDeviceScaleFactor — fix blur on low-DPI displays (pageZoom / RasterizationScale)#38
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…-DPI Floors the WebView's effective render scale so content stays sharp when the host scales the editor up on a low-DPI display, where the OS otherwise upscales a 1x raster (blurry, most visibly text). A high-DPI display already exceeds the floor, so it's a no-op there. Both backends shrink the CSS viewport, so the option is documented as responsive-content-only. - macOS: public WKWebView.pageZoom (macOS 11+), applied as max(1, min/backing) in viewDidChangeBackingProperties so it tracks display moves and no-ops on Retina. - Windows: public ICoreWebView2Controller3::put_RasterizationScale = max(min, monitorScale), with ShouldDetectMonitorScaleChanges off and re-applied from the scale-factor notifier. No private SPI; both levers are documented public API. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
The player webview renders blurry on low-DPI (non-Retina / 100%) displays. Confirmed on a secondary 1920×1080 monitor:
devicePixelRatio = 1, CSS viewport1323, fitscale(1.467)— the fixed-size design is upscaled with no backing-resolution headroom.Change
Adds
withMinimumDeviceScaleFactor(double)to bothAppleWkWebViewandWinWebView2— a floor on the WebView's effective render scale, via public APIs:WKWebView.pageZoom(macOS 11+), applied asmax(1, min/backingScaleFactor)inviewDidChangeBackingProperties(tracks display moves; no-op on Retina).ICoreWebView2Controller3::put_RasterizationScale=max(min, monitorScale), monitor auto-detection disabled, re-applied from the scale-factor notifier.Both re-rasterise content at higher density and shrink the CSS viewport, so this is documented as responsive-content-only. Verified on macOS: with
.withMinimumDeviceScaleFactor(2.0), the same monitor reports viewport661/ fitscale(0.733)— the design now downscales off a 2×-rendered page → sharp.Consumer opt-in is in
minimal_core(MKUEmbeddedWebView).Testing
macOS AU/VST3/Standalone green; blur confirmed cleared on a real 1× secondary monitor. Windows path unbuilt (no toolchain) — needs a Windows compile.
🤖 Generated with Claude Code