Fix #622: Linux client settings GUI

[amillionbouncyballs]

⚠️ CAREFUL - DEFAULT CACHE LIMIT IS 10 GB ⚠️

The easiest way to test this PR without losing your videos via the default generated settings.json having a 10GB cache limit and ejecting videos above this limit is:

# Back up your config
cp ~/.config/infinidream/settings.json ~/.config/infinidream/settings.json.bak

# Clear only the sealed session
python -c "
import json
path = '$HOME/.config/infinidream/settings.json'
d = json.load(open(path))
d['settings']['content']['sealed_session'] = ''
open(path, 'w').write(json.dumps(d, indent=4))
print('Token cleared')
"

# Run the app
./client_generic/LinuxBuild/build/infinidream

# Restore your config when done
cp ~/.config/infinidream/settings.json.bak ~/.config/infinidream/settings.json

Your cache dir (~/.config/infinidream/content), playlist UUIDs, and all other settings stay untouched. Only the auth token is blanked.

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PR Details

Implements a 3-step ImGui sign-in wizard for the Linux client, replacing the previous console prompt. Matches the look and flow of the Mac/Windows wizard (ported from FirstTimeSetupWin32.cpp). Also wires up the pre-existing SettingsDialogVulkan (which was compiled but never reachable), adds HiDPI scaling, fixes X11 overlay input, and addresses several bugs found during review.

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Sign-in wizard (FirstTimeSetupVulkan)

• EDreamClient.cpp — ESHasFirstTimeSetupCallback() added so the console login path is skipped when the GUI wizard is registered. Removed a guard on settings.app.firsttimesetup that was preventing the wizard from re-appearing after a session wipe (auth token cleared).
• client.h — Linux pre-window auth block now skips the console prompt entirely when the GUI wizard is registered.
• client_linux.h — Registers the wizard callback before CElectricSheep::Startup() runs; suppresses event loop while wizard is visible.
• RendererVulkan.cpp — Calls FirstTimeSetupVulkan_DrawIfNeeded() inside the existing ImGui frame.
• CMakeLists.txt — Added FirstTimeSetupVulkan.cpp to sources.

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Settings dialog (SettingsDialogVulkan)

SettingsDialogVulkan was compiled but never registered, drawn, or reachable. Now fully wired up:

• CMakeLists.txt — Added SettingsDialogVulkan.cpp to sources.
• client_linux.h — Registers the dialog callback; SettingsDialogVulkan_IsVisible() guard added alongside the wizard guard; Ctrl+, mapped to ESShowPreferences().
• RendererVulkan.cpp — Calls SettingsDialogVulkan_DrawIfNeeded() immediately after the wizard draw.
• DisplayVulkan.cpp — Keyboard and mouse Wayland events fed to the settings dialog alongside the wizard. ClearInputKeys() called on show to prevent stale ImGui key state (e.g. Escape held from closing the wizard) from immediately dismissing the dialog on its first frame.

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HiDPI / DPI scaling

Previously both dialogs hardcoded g_uiScale = 1.0f. Now derived from the actual display:

• PlatformUtils_Internal.h / PlatformUtils_Linux.cpp — New PlatformUtils_InitUIScale() / GetUIScale() / SetUIScale() (clamped 1–4×). Seeds from GDK_SCALE / QT_SCALE_FACTOR env vars as a fallback before display-specific init runs.
• DisplayVulkan.cpp (Wayland) — Binds wl_output; computes DPI = pixelWidth × 25.4 / physWidthMm on the done event; uses the highest scale across all connected outputs so a lower-DPI secondary monitor cannot overwrite a HiDPI primary.
• DisplayVulkan.cpp (X11) — Computes DPI from DisplayWidthMM() after XOpenDisplay.
• Both dialogs refresh g_uiScale from PlatformUtils_GetUIScale() at show time, before loading fonts.

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X11 overlay input

On X11 sessions the wizard and settings dialog rendered but accepted no keyboard or mouse input, making them inescapable. Fixed in DisplayVulkan.cpp:

• Keyboard — keysym saved before XFree(); both overlays' FeedKey called with evdevKey = keycode − 8; event consumed (continue) if either overlay accepts it.
• Mouse position — MotionNotify forwarded to both overlays via FeedMousePos.
• Mouse buttons — ButtonPress/ButtonRelease mapped from X11 button numbers to BTN_LEFT/RIGHT/MIDDLE and forwarded via FeedMouseButton.
• Cursor — applyInvisibleCursor() is called at init; applyDefaultCursor() restores a visible pointer while any overlay is open, then hides it again on dismiss.
• Ctrl+, — XKB_KEY_comma added to the Wayland keysym switch (was missing, so the shortcut was silently dropped on Wayland).

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Wizard UI polish

• Button and input font bumped to S(20) (20 logical px at 96 DPI, scaled by display DPI). All buttons widened to fit.
• OTP step layout reworked: error message was positioned at y=144 with only 14 px before the Verify button. Replaced fixed-Y layout with flow-based positioning so the error message naturally pushes buttons down. Panel height expanded 250 → 330.
• Error messages and "Verifying…" label now use the button font instead of the tiny body font.

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Other

• DreamDownloader.cpp — Adds a "All playlist dreams cached" log warning when the downloader finds nothing to fetch. Unrelated to sign-in; happy to split to a separate PR if preferred.
• PlatformUtils_Internal.h / PlatformUtils_Linux.cpp — PlatformUtils_GetMouseCallback() renamed to PlatformUtils_GetOnMouseMovedCallback().
• DisplayVulkan.cpp — s_mouseCallback renamed to s_onMouseMovedCallback.

[amillionbouncyballs]

Mac & Windows auth regression fixed in a9fabb3

[scottdraves]

Reviewed and built this branch locally (Wayland, fresh HOME). The sign-in wizard itself works well on Wayland — clean build, console prompt correctly skipped, auth fail-over reaches the wizard. A few things need fixing before this is ready:

1. Settings dialog is dead code — please wire it up

SettingsDialogVulkan.{cpp,h} plus the 7 .inl tab files (~1,370 lines, over half the diff) are never compiled or invoked:

• SettingsDialogVulkan.cpp is not in LinuxBuild/CMakeLists.txt (only FirstTimeSetupVulkan.cpp was added).
• SettingsDialogVulkan_Register() is never called anywhere — so the ESSetShowPreferencesCallback is never registered and ESShowPreferences() stays a no-op on Linux.
• There's no draw hook (RendererVulkan only calls FirstTimeSetupVulkan_DrawIfNeeded()) and no Ctrl+, key binding in client_linux.h.

The linked issue (#622) explicitly asks for both a settings window and sign-in, so we do want this — it just needs to be fully connected: add the source to CMake, call SettingsDialogVulkan_Register() at startup, add the draw hook in RendererVulkan::EndFrame(), route input through DisplayVulkan, and add the Ctrl+, trigger. (Or, if it's not ready, split it into a follow-up PR so what merges matches what runs.)

2. Wizard is Wayland-only — X11 sessions get a dead, inescapable overlay

The wizard's input feeds (FirstTimeSetupVulkan_FeedKey/FeedMouseButton) are only called from the Wayland callbacks in DisplayVulkan.cpp. The X11 path (DisplayVulkan.cpp:825-852 — any session without WAYLAND_DISPLAY, and always for XScreensaver embeds) feeds the wizard nothing. Meanwhile client_linux.h swallows all key events while the wizard is visible. Net result on X11: the wizard renders but accepts no typing/clicks, Skip is unreachable, and the old console login is suppressed — a regression. Please feed the X11 KeyPress/MotionNotify/ButtonPress events into the wizard too (the X11 event loop is already in CDisplayVulkan::checkEvents()), or fall back to the console flow when not on Wayland.

3. Font sizes / readability

Both FirstTimeSetupVulkan.cpp and SettingsDialogVulkan.cpp hardcode g_uiScale = 1.0f with // no DPI scaling applied yet, and load fonts at fixed logical-pixel sizes. On a HiDPI display this renders everything at half-size and the text is hard to read. Please derive the scale from the display (Wayland wl_output scale / wp_fractional_scale, or the X11 DPI) and apply it to g_uiScale so font sizes and layout track the actual display.

4. Issue reference is wrong

The PR title says "Fix #621", but #621 is the unrelated "linux client appimage build should be python" issue. This work targets #622 ("linux client settings GUI"). Please correct the reference.

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Also: the DreamDownloader.cpp change (the "All playlist dreams cached" warning) is unrelated to sign-in and isn't mentioned in the PR description. It looks fine, but please either note it in the description or split it out.

[scottdraves]

cool, i am seeing the settings now, but the font sizes and layout are off in the dialogs.
also there is a regression in the typeface of the text overlay, it was Lato before and now it's reverted.

[amillionbouncyballs]

...the font sizes and layout are off in the dialogs. also there is a regression in the typeface of the text overlay, it was Lato before and now it's reverted.

Fixed in a28786b