fix(android): treat VK_SUBOPTIMAL_KHR as success in the presenter - #1
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KLCLAU wants to merge 1 commit into
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fix(android): treat VK_SUBOPTIMAL_KHR as success in the presenter#1KLCLAU wants to merge 1 commit into
KLCLAU wants to merge 1 commit into
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On Android the display surface is portrait-native while the game renders landscape, so surfaceCapabilities.currentTransform is a 90/270-degree rotation that the swapchain's preTransform never matches. Every vkAcquireNextImageKHR / vkQueuePresentKHR then returns VK_SUBOPTIMAL_KHR and Presenter treats it like OUT_OF_DATE, recreating the swapchain on *every single frame* (observed: 761 'recreating swapchain' log lines in 45 seconds, plus the wasted GPU work). The acquired image is fully usable and the Android compositor performs the rotation for free, so on __ANDROID__ treat VK_SUBOPTIMAL_KHR as success for the recreate decision (presenterResultOk). Non-Android behaviour is unchanged. With this, the recreate-per-frame loop drops from 761 to 0 on a Galaxy S26+ (Adreno 840) and the game holds a steady frame rate in menus and in-game. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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Problem
On Android the display surface is portrait-native while GeneralsX renders landscape, so
surfaceCapabilities.currentTransformis a 90/270° rotation the swapchain'spreTransformnever matches. EveryvkAcquireNextImageKHR/vkQueuePresentKHRreturnsVK_SUBOPTIMAL_KHR, andPresentertreats that likeVK_ERROR_OUT_OF_DATE_KHR— recreating the swapchain every single frame:Fix
The acquired image is fully usable and the Android compositor does the rotation for free, so on
__ANDROID__treatVK_SUBOPTIMAL_KHRas success for the recreate decision (presenterResultOk()), at all three sites: the post-acquire check, the pre-acquire-after-present optimization, and the post-present dirty flag. Desktop behaviour is unchanged (presenterResultOkisr == VK_SUCCESSoff Android).Result: recreate-per-frame loop 761 → 0; steady frame rate in menus and in-game on Adreno 840.
A proper pre-rotation implementation (render with
preTransform == currentTransform, apply the inverse in the final blit) would be better still, but this stops the pathological loop with a one-liner and no behavioural risk.Companion to fadi-labib/Generals-Android#24.