ios: report view pixel size + contentScaleFactor as dpi_scale#649
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draw_in_rect reported UIScreen.bounds * UIScreen.scale as the rendered size. On real iPhone / iPad that matches the view's framebuffer (the view fills the screen), but on iOS-on-Mac the view can be a window smaller than the Mac display — so screen_width / screen_height overstated the real rendering surface and apps drew at the wrong scale in windowed mode. Switch to the view's own bounds * contentScaleFactor, which is correct in both cases. Also populate native_display().dpi_scale with the view's contentScaleFactor — upstream left it at the 1.0 default on iOS, which breaks higher-level APIs (e.g. macroquad's screen_width() divides by dpi_scale to return density-independent units). With this change, iOS joins macOS in reporting a real content scale, and the same dp-positioned UI lands at matching screen positions across both platforms.
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Summary
Two related changes to make iOS's reported metrics match the actual rendering surface:
Populate
dpi_scalefromcontentScaleFactor. Upstream leftnative_display().dpi_scaleat1.0on iOS. macroquad'sscreen_width()/mouse_position()divide bydpi_scaleto return density-independent units — so without this, iOS callers got pixel values where macOS got points, and dp-positioned UI landed at the wrong place. Now iOS joins macOS in reporting a real content scale.Measure the view, not
UIScreen.draw_in_rectreportedUIScreen.bounds × UIScreen.scaleas the rendered size. Switched topayload.view.bounds × contentScaleFactor, which is more direct (the view IS the rendering surface) and avoids the globalUIScreen.mainScreencall that has gotchas with multi-window configurations.Both halves go together: the natural scale to multiply the view's
boundsby is the view's owncontentScaleFactor, and once we're reading it for that, exposing it asdpi_scaleis essentially free.The
high_dpitoggle is no longer consulted here — the view'scontentScaleFactoris already set toUIScreen.scalewhenhigh_dpi=trueand1.0whenhigh_dpi=false(seecreate_opengl_view), so the resultingscreen_size/dpi_scalematch upstream's high_dpi-aware branches on real iPhone / iPad.What this fixes
In a downstream macroquad app, iOS-on-Mac windowed mode was rendering at ~50 % of the window size. The fix is the
dpi_scalehalf — macroquad'sscreen_width()was returning physical-pixel counts where the macOS desktop returned points, so the rest of the app drew at half the expected scale.(Side note on the bounds half: iOS-on-Mac windowed reports the same
view.boundsas fullscreen — the window chrome clips a fixed-size view rather than shrinking it. So the change fromUIScreen.boundsis more about avoiding theUIScreen.mainScreenglobal and being more direct than about fixing the windowed-rendering bug per se.)Test plan
contentScaleFactor = 3):screen_width()reports 402 dp instead of 1206 px.