Fix splash screen upside down on Android

Fixes an issue introduced in #96439 (see
https://github.com/godotengine/godot/pull/96439#issuecomment-2447288702)

Godot was relying on Java's
activity.getWindowManager().getDefaultDisplay().getRotation(); to apply
pre-rotation but this is wrong.

First, getRotation() may temporarily return a different value from the
correct one; which is what was causing the splash screen to be upside
down. It would return -90 instead of 90 for the first rendered frame.

But unfortunately, the splash screen is just one frame rendered for a
very long time, so the error lingered for a long time for everyone to
see.

Second, to determine what rotation to use, we should be looking at what
Vulkan told us, which is the value we pass to
VkSurfaceTransformFlagBitsKHR::preTransform.

This commit removes the now-unnecessary
screen_get_internal_current_rotation() function (which was introduced by
#96439) and now saves the preTransform value in the swapchain.

1 files changed, 25 insertions, 0 deletions

diff --git a/drivers/vulkan/rendering_device_driver_vulkan.cpp b/drivers/vulkan/rendering_device_driver_vulkan.cpp
index f9f1168a97..4be64590dc 100644
--- a/drivers/vulkan/rendering_device_driver_vulkan.cpp
+++ b/drivers/vulkan/rendering_device_driver_vulkan.cpp
@@ -2996,6 +2996,24 @@ Error RenderingDeviceDriverVulkan::swap_chain_resize(CommandQueueID p_cmd_queue,
 	swap_create_info.imageUsage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
 	swap_create_info.imageSharingMode = VK_SHARING_MODE_EXCLUSIVE;
 	swap_create_info.preTransform = surface_transform_bits;
+	switch (swap_create_info.preTransform) {
+		case VK_SURFACE_TRANSFORM_IDENTITY_BIT_KHR:
+			swap_chain->pre_transform_rotation_degrees = 0;
+			break;
+		case VK_SURFACE_TRANSFORM_ROTATE_90_BIT_KHR:
+			swap_chain->pre_transform_rotation_degrees = 90;
+			break;
+		case VK_SURFACE_TRANSFORM_ROTATE_180_BIT_KHR:
+			swap_chain->pre_transform_rotation_degrees = 180;
+			break;
+		case VK_SURFACE_TRANSFORM_ROTATE_270_BIT_KHR:
+			swap_chain->pre_transform_rotation_degrees = 270;
+			break;
+		default:
+			WARN_PRINT("Unexpected swap_create_info.preTransform = " + itos(swap_create_info.preTransform) + ".");
+			swap_chain->pre_transform_rotation_degrees = 0;
+			break;
+	}
 	swap_create_info.compositeAlpha = composite_alpha;
 	swap_create_info.presentMode = present_mode;
 	swap_create_info.clipped = true;
@@ -3167,6 +3185,13 @@ RDD::RenderPassID RenderingDeviceDriverVulkan::swap_chain_get_render_pass(SwapCh
 	return swap_chain->render_pass;
 }
 
+int RenderingDeviceDriverVulkan::swap_chain_get_pre_rotation_degrees(SwapChainID p_swap_chain) {
+	DEV_ASSERT(p_swap_chain.id != 0);
+
+	SwapChain *swap_chain = (SwapChain *)(p_swap_chain.id);
+	return swap_chain->pre_transform_rotation_degrees;
+}
+
 RDD::DataFormat RenderingDeviceDriverVulkan::swap_chain_get_format(SwapChainID p_swap_chain) {
 	DEV_ASSERT(p_swap_chain.id != 0);