diff --git a/ios/Platform/Platform/ContentView.swift b/ios/Platform/Platform/ContentView.swift
index 90ed19b..61d28fe 100644
--- a/ios/Platform/Platform/ContentView.swift
+++ b/ios/Platform/Platform/ContentView.swift
@@ -94,7 +94,10 @@ struct MainTabView: View {
}
.task {
guard showReader else { return }
- _ = ArticleRenderer.shared
+ let renderer = ArticleRenderer.shared
+ // Window is now available — ensure WKWebView is attached
+ // so GPU compositor launches during startup, not first article tap
+ renderer.ensureAttachedToWindow()
await readerVM.loadInitial()
}
}
diff --git a/ios/Platform/Platform/Features/Reader/Views/ArticleWebView.swift b/ios/Platform/Platform/Features/Reader/Views/ArticleWebView.swift
index 8d1285f..99666b7 100644
--- a/ios/Platform/Platform/Features/Reader/Views/ArticleWebView.swift
+++ b/ios/Platform/Platform/Features/Reader/Views/ArticleWebView.swift
@@ -10,20 +10,34 @@ final class ArticleRenderer {
let webView: WKWebView
private init() {
+ let t0 = CFAbsoluteTimeGetCurrent()
+ print("[WARMUP] ArticleRenderer.init started")
+
let config = WKWebViewConfiguration()
config.allowsInlineMediaPlayback = true
- webView = WKWebView(frame: .zero, configuration: config)
+ // Create at screen size (not .zero) so WebKit initializes the
+ // GPU compositor during warmup, not on first article open.
+ let screenBounds = UIScreen.main.bounds
+ webView = WKWebView(frame: screenBounds, configuration: config)
webView.isOpaque = false
webView.backgroundColor = .clear
webView.scrollView.isScrollEnabled = true
- // Pre-warm with realistic content. An empty
- // only warms the WebContent process. Loading the real CSS template with
- // sample text forces WebKit to also parse CSS, load/measure system fonts,
- // initialize the layout engine, and spin up the compositing pipeline.
- // This shifts the ~3s first-render cost to app launch (background) so the
- // first article open doesn't stall.
+ // Attach to the key window briefly to force GPU process launch.
+ // The WKWebView must be in a real window hierarchy for WebKit to
+ // spin up the GPU compositor. At .zero frame or detached, it skips
+ // GPU init — causing a ~3s stall on first real display.
+ if let window = UIApplication.shared.connectedScenes
+ .compactMap({ $0 as? UIWindowScene }).first?.windows.first {
+ webView.alpha = 0 // invisible
+ window.addSubview(webView)
+ print("[WARMUP] attached to window")
+ } else {
+ print("[WARMUP] no window available yet — will attach later")
+ }
+
+ // Load realistic content to warm CSS parsing, font loading, layout
webView.loadHTMLString(ArticleHTMLBuilder.build(
title: "Warming up",
url: nil,
@@ -38,8 +52,34 @@ final class ArticleRenderer {
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Quoted text for blockquote styling.
code { display: block; }
+ 
"""
), baseURL: nil)
+
+ // Remove from window after a delay (GPU process stays alive)
+ DispatchQueue.main.asyncAfter(deadline: .now() + 2) { [weak webView] in
+ webView?.removeFromSuperview()
+ webView?.alpha = 1
+ print("[WARMUP] detached from window +\(Int((CFAbsoluteTimeGetCurrent()-t0)*1000))ms")
+ }
+
+ print("[WARMUP] init complete +\(Int((CFAbsoluteTimeGetCurrent()-t0)*1000))ms")
+ }
+
+ /// Call this after app window is available if init ran too early
+ func ensureAttachedToWindow() {
+ guard webView.window == nil else { return }
+ if let window = UIApplication.shared.connectedScenes
+ .compactMap({ $0 as? UIWindowScene }).first?.windows.first {
+ webView.alpha = 0
+ window.addSubview(webView)
+ print("[WARMUP] late-attached to window")
+ DispatchQueue.main.asyncAfter(deadline: .now() + 2) { [weak self] in
+ self?.webView.removeFromSuperview()
+ self?.webView.alpha = 1
+ print("[WARMUP] late-detached from window")
+ }
+ }
}
}