After joining Intel for some months, I collect different categories of works and positions here, and get to know the different focus people are on. As an End-to-end validation engineer, I am happy that I get a chance to work with different teams.
“Graphics Software Engineer” I mean here is not just for pure “Computer Graphics Appilication”, but more for “GPU Software Engineer”. Shader processing, rendering or calculating is not only in graphics related feature but more like in everywhere, so I am putting all relevant parts here, as a brief introduction on what we are expecting when we are speaking about graphics driver.
First of all, as a software engineer, GPU drivers are the most important things we take care. Below are different component teams working on different parts of a GPU driver.
Kernel Mode Driver: Focusing on OS kernels, enable the new hardware in general operations, including memory management, power management, workload scheduling, ect.
User Mode Driver – Graphics: For graphics area, there are 4 major graphics API drivers: [Vulkan, OpenGL, DirectX12, DirectX(*before12)]. Vulkan and OpenGL are generic for both Windows and Linux. DirectX is a graphics API provided and maintained by Microsoft for Windows systems. DirectX series are the most commonly used graphics API in the most popular games. DirectX12 is separated out is mainly because the change is huge. DirectX12 to DirectX10 is like Vulkan to OpenGL.
User Mode Driver – Media: While playing videos or using video editing software, the driver handles encoding and decoding process. Note that sometimes media driver is using graphics APIs as well.
User Mode Driver – Display: The rendering results will need to be shown on the connected display. This part is focusing on display protocols and data synchronizations.
Compiler: Shader codes need to be compiled to be recognized and executed. We all know that OpenGL and other shader languages are designed to be compiled during the execution of applications, because the application never knows what the hardware to be installed on, but we also have situations that shader codes need to be compiled ahead of time. And also, specially for DirectX, shader codes are compiled twice. 1 time during compilation, 1 time during the compilation (to DXBC) and the other to the specific hardware.
User Mode Driver – OpenCL: OpenCL is a common API across different platforms. This is the very basic part to design some GPGPU applications. Although it exists in both Linux and Windows, more and more modern solutions are popping out to replace it.
User Mode Driver – Specialized high performance computing component (HCP): GPU provider specialized component. CUDA for Nvidia, OneApi for Intel, ect.
System Control: Some GPU devices provide interfaces to control hardware system, like overclocking. Intel Arc Control provides you the ability to adjust overclocking during real-time.
AI: In most cases it is not a separate component, but most likely to be a part of other user mode drivers. E.x. DirectML for AI on windows, Cuda/OneAPI for Linux, ect
TOBE CONTINUE… Pre & Post Silicon, hardware validation, software component validation, software tools, end to end validation.
The best OpenGL Tutorial so far. Explanations are clear and accurate, babysat me through the headache times:)
No need to follow every coding part as he was doing, since the version of OpenGL may be different. (My work is mainly focus on OpenGL ES). The main idea is understand how graphics pipeline works, understand the meanings of the main terms like VAO, VBO, EBO, and get familiar with common APIs for draw shapes or textures.
Best learning website with all needed knowledge and codes. Have been following this website to do all the practices. Each lesson includes detailed explanations and corresponding codes that I can directly have some hands-on test.
Learn from your favorite applications
Graphics technology is widely used in different kinds of applications, especially in games. To understand how your favorite application is rendering beautiful scenes on the screen, here are 2 main tools(Open source project) you can refer:
Note that for both tools, only supported API can be captured. They have great support in some kinds like Android mobile games developed in Unreal or Unity, but not all applications are easy to captured.
After getting a trace, you can review the opengl function calls and see how they are drawn and rendered as the final result.
Where to find more sample projects?
If you google OpenGL examples, you will only find some old, simple and duplicated examples, even the https://learnopengl.com/ website can offer better examples. But if you want to draw something very fancy, with very complicated effects, there is a special kind of OpenGL ES called WebGL, which uses pretty much similar APIs like real OpenGL shaders but slightly different.
By opening WebGL applications, it will render the shaders in your browser(Or other platforms like VS codes). There is a website that stores many WebGL projects that you can easily see the codes and final results with real-time rendering on web pages:
ShaderToy provides tons of beautiful projects that can be running on your computer by a single click! This is also a very good tool for shader coders that they can see the render scenes in real-time. Also, you can transform it easily back to traditional OpenGL shaders easily, by using WebGL shaders as fragment shader and putting a passthrough vertex shader.(Some changes on API is needed)
Those are some resources helping me a lot in my daily work and study. It’s 2021 and thanks to the internet I don’t need to buy a textbook or pay for a course. I Feel free to leave a comment if you find some other resources that really helpful in studying OpenGL or useful in your daily work. I will keep this page updated while I find new things that improves my skills.