Hands On Projects For The Linux Graphics Subsystem 2021 | GENUINE × HANDBOOK |

Developing for the Linux graphics subsystem involves bridging the gap between high-level user applications and low-level kernel drivers. This complex stack includes the Direct Rendering Manager (DRM), Kernel Mode Setting (KMS), and userspace components like Mesa 3D and compositors (Wayland/X11).

Real-world tracing, identifying locks/contention, and optimization strategies.

Learning outcomes:

Attack surface understanding and defensive coding techniques for graphics stacks.

drmModeGetResources – get list of connectors, encoders, CRTCs.
drmModeGetConnector – find a connected connector.
drmModeGetEncoder / drmModeGetCrtc – find a suitable CRTC.
drmIoctl(DRM_IOCTL_MODE_CREATE_DUMB) – allocate memory.
drmModeAddFB – create a framebuffer object.
drmModeSetCrtc – set mode and display the buffer.

Project 3: Patch Mesa to Add a Custom debug printf

Goal: Recompile Mesa (the open-source GPU driver stack) with a custom log that prints every time a shader is compiled. Hands On Projects For The Linux Graphics Subsystem

Step 1: Research existing graphics toolkits, such as GTK+ or Qt.
Step 2: Design and implement a new graphics toolkit that provides a simple and easy-to-use API.
Step 3: Test and refine the toolkit.

Virtual Kernel Mode Setting (VKMS) Implementation: A highly recommended academic project is contributing to or building upon VKMS, a software-only model of a KMS driver used for testing. Learning outcomes:

Install libwayland-dev.
Write a Wayland client that connects to the compositor.
Use wl_display_get_registry to bind to the compositor interfaces.
Create a Surface (wl_surface) and a Shell Surface.
Allocate a shared memory buffer (shm) manually in C.
Write pixel data (RGBA values) directly into that memory buffer to draw a gradient or solid color.
Attach the buffer to the surface and commit it.