Drawing multiple objects in Vulkan [closed]

Question

I've been working on creating a game with a Vulkan rendering backend and I therefore need to be able to draw multiple objects on the screen. I've worked with OpenGL before so I have a little experience in graphics programming.

I've gone through the tutorial at https://vulkan-tutorial.com/ and I more or less understand the basic ideas however there are so many moving parts I find it pretty difficult to wrap my head around it all. So far I'm able to draw a single object with essentially an arbitrary number of vertices with a UBO but no more than 1 since I don't know what to decouple from the main renderer object into a drawable object.

I don't really know what pieces need to live in a vulkan-context object and what parts are independent/live on each drawable object. I've tried doing some research and most of what I can find has to do with instancing which isn't really what I'm looking to do just yet.

Answer 1

There's many options for how to organize this, so there's no single answer. But generally speaking a drawable scene object will need

• A VkPipeline describing the state and shaders to use when drawing the object.
• One or more VkDescriptorSets that bind resource references in the shader to state and data in Vulkan API objects.
• The actual data or data-containing-objects (images, buffers) to use for the drawable.

For the latter two, you don't necessarily have a distinct API objects for each drawable. Instead, your drawable might just have the data and you obtain an API object (like a descriptor set) and fill it in each time you draw, then recycle it. Or you might have a single VkBuffer shared by many drawables, with each drawable's geometry occupying a sub-range of the buffer.

Your "context", on the other hand, will have a VkDevice, VkQueue(s), and various pool objects like command buffer pools, descriptor pools. You'll also usually have some way of keeping track of things that should be recycled or destroyed when command buffers have completed (usually at frame granularity).