Graphics: Replace RenderFrame by RenderResources

This changes makes the whole rendering independent from the RenderFrame acquired from the Swapchain.
This may allow to do offscreen rendering (= without swapchain), or multi-window rendering in the future

src/Nazara/VulkanRenderer/VulkanRenderImage.cpp

@@ -53,6 +53,11 @@ namespace Nz
 		SubmitCommandBuffer(commandBuffer, queueTypeFlags);
 	}
 
+	UInt32 VulkanRenderImage::GetImageIndex() const
+	{
+		return m_imageIndex;
+	}
+
 	VulkanUploadPool& VulkanRenderImage::GetUploadPool()
 	{
 		return m_uploadPool;

src/Nazara/VulkanRenderer/VulkanSwapchain.cpp

@@ -246,7 +246,7 @@ namespace Nz
 
 		currentFrame.Reset(imageIndex);
 
-		return RenderFrame(&currentFrame, invalidateFramebuffer, m_swapchainSize, imageIndex);
+		return RenderFrame(&currentFrame, invalidateFramebuffer, m_swapchainSize);
 	}
 
 	std::shared_ptr<CommandPool> VulkanSwapchain::CreateCommandPool(QueueType queueType)
@@ -324,6 +324,11 @@ namespace Nz
 		return m_supportedPresentModes;
 	}
 
+	RenderResources& VulkanSwapchain::GetTransientResources()
+	{
+		return *m_concurrentImageData[m_currentFrame];
+	}
+
 	void VulkanSwapchain::NotifyResize(const Vector2ui& newSize)
 	{
 		OnSwapchainResize(this, newSize);
@@ -375,11 +380,6 @@ namespace Nz
 		}
 	}
 
-	TransientResources& VulkanSwapchain::Transient()
-	{
-		return *m_concurrentImageData[m_currentFrame];
-	}
-
 	bool VulkanSwapchain::SetupDepthBuffer()
 	{
 		VkImageCreateInfo imageCreateInfo = {