Feature request: Support importing Vulkan textures with different layouts in SDL_CreateTextureWithProperties

[anonymix007]

Currently SDL_PROP_TEXTURE_CREATE_VULKAN_TEXTURE_NUMBER expects

the VkImage with layout VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL associated with the texture

However, external producers such as GStreamer or FFmpeg may produce other layouts (i.e. when Vulkan decoders are used). It would be really convenient to directly import them into SDL_Texture without users having to do the conversion. This feature would be especially useful since SDL_Renderer doesn't expose its internal command buffers and/or queues.

For example, this may be implemented by introducing SDL_PROP_TEXTURE_CREATE_VULKAN_LAYOUT_NUMBER which will default to VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL. Then, SDL would convert image to whatever format it needs.

[slouken]

We don't have any plans to add this, but feel free to create a PR if you like.

[anonymix007]

Would it be enough to call

VULKAN_RecordPipelineImageBarrier(rendererData, 
    VK_ACCESS_NONE,
    VK_ACCESS_SHADER_SAMPLED_READ_BIT,
    VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT,
    VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT,
    VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL, 
    imageOut->image, 
    &oldLayout);

in VULKAN_AllocateImage just before setting the imageOut->imageLayout or is it much more complicated than that?