Vulkan-Demo-1

Coding Session 2025 by Malfunction, Scotch and Belial

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Build

• Release: cmake -DCMAKE_BUILD_TYPE=Release ..
• Debug: cmake -DCMAKE_BUILD_TYPE=Debug ..

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Vulkan Cheat Sheet

In case you are not familiar with the vulkan API, the following sections describe the most important components.

🧱 Instance & Surface

VkInstance

• Entry point into the Vulkan API.
• The Vulkan loader uses the instance to find the appropriate drivers and available extensions.

VkSurfaceKHR

• Represents the window (e.g., from GLFW) that will be drawn to.
• Vulkan uses the surface to pass rendered images to the window system.

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🧠 Devices & Queues

VkPhysicalDevice

• The actual GPU in the system.
• Provides information about the hardware’s capabilities (e.g., supported formats and queues).

VkDevice (Logical Device)

• Software interface to the selected GPU.
• Enables creation of resources and sending commands to the GPU.

VkQueue

• A queue where command buffers are submitted for execution.
• Your graphicsQueue processes draw commands and presentation commands.

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🖼️ Swapchain & Images

VkSwapchainKHR

• A set of images displayed on the screen (double/triple buffering).
• The GPU renders into these images, which are then presented.

VkImage

• Raw memory object from the swapchain.
• Contains the actual color image for the current frame.

VkImageView

• Provides access to a VkImage, e.g., as a color attachment in the render pass.
• Specifies how the image should be interpreted.

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🎨 Render Infrastructure

VkRenderPass

• Describes how the framebuffer images are used (clear, load, store).
• Defines layout transitions and subpasses.

VkFramebuffer

• Combines one or more VkImageViews with a VkRenderPass.
• Represents the concrete target image for the current frame.

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🛠️ Drawing & Pipeline

VkShaderModule

• Compiled shader code in SPIR-V format.
• Used in the pipeline to define the vertex and fragment stages.

VkPipelineLayout

• Container for resources like descriptor sets or push constants.
• Empty in our example, but still required.

VkPipeline (Graphics Pipeline)

• Comprehensive description of all drawing parameters:
  • Shader stages
  • Vertex input
  • Rasterizer
  • Color processing
  • Render target type
• Must be compatible with the VkRenderPass.

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✍️ Command Infrastructure

VkCommandPool

• Memory management for VkCommandBuffer.
• Must be associated with a specific queue family.

VkCommandBuffer

• List of GPU commands such as vkCmdDraw, vkCmdBindPipeline, etc.
• Recorded once before rendering.

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🔄 Draw Loop Synchronization

VkSemaphore (imageAvailableSemaphore & renderFinishedSemaphore)

• GPU synchronization objects:
  • imageAvailableSemaphore: signals that an image is available.
  • renderFinishedSemaphore: signals that rendering is complete and the image can be presented.

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🔁 Frame Flow

1. Acquire Image (vkAcquireNextImageKHR)

   • Gets the next available swapchain image.
   • Waits on the imageAvailableSemaphore.

2. Submit Command Buffer (vkQueueSubmit)

   • Executes the recorded draw commands.
   • Waits on the imageAvailableSemaphore.
   • Signals the renderFinishedSemaphore.

3. Present (vkQueuePresentKHR)

   • Displays the finished image in the window.
   • Waits on the renderFinishedSemaphore.