What's your process for testing rendering code?

1 Use automated tests

Automated tests are a powerful tool for testing rendering code, as they can help you detect errors, bugs, and regressions quickly and reliably. Automated tests can be either unit tests, which test individual functions or classes, or integration tests, which test the interaction of different components or systems. You can use frameworks like Google Test, Catch2, or PyTest to write and run automated tests for your rendering code. Automated tests should cover the most critical and common scenarios, such as rendering different types of geometry, materials, lights, and cameras, and checking the output against expected results or reference images.

2 Use debug tools

Debug tools are another useful tool for testing rendering code, as they can help you inspect and analyze the state of your rendering pipeline, such as the shaders, buffers, textures, and commands. Debug tools can also help you identify performance bottlenecks, memory leaks, and rendering artifacts. You can use tools like RenderDoc, Nsight Graphics, or PIX to capture and replay your rendering frames, and examine the details of each draw call, resource, and event. Debug tools can help you verify the correctness and efficiency of your rendering code, and find and fix issues that are hard to spot otherwise.

3 Use visual tests

Visual tests are a complementary tool for testing rendering code, as they can help you evaluate the quality and aesthetics of your rendering output, such as the colors, lighting, shadows, reflections, and post-processing effects. Visual tests can be either manual or automated, depending on the complexity and frequency of the tests. Manual visual tests involve looking at the rendering output on different devices, resolutions, and settings, and comparing it with your design goals or reference images. Automated visual tests involve using tools like ImageMagick, OpenCV, or Selenium to compare the rendering output with a baseline image, and report any differences or errors.

4 Use code reviews

Code reviews are a collaborative tool for testing rendering code, as they can help you improve the readability, maintainability, and security of your code, and learn from your peers. Code reviews involve having another developer or team member review your code before merging it to the main branch, and provide feedback, suggestions, or corrections. You can use tools like GitHub, GitLab, or Gerrit to facilitate code reviews, and follow some best practices, such as keeping your changes small and focused, following coding standards and conventions, and documenting your code properly.

5 Use user feedback

User feedback is a valuable tool for testing rendering code, as it can help you understand how your users perceive and interact with your rendering output, and what are their needs and expectations. User feedback can be either qualitative or quantitative, depending on the type and amount of data you collect and analyze. Qualitative user feedback involves asking your users for their opinions, preferences, or suggestions, through methods like surveys, interviews, or focus groups. Quantitative user feedback involves measuring your users' behavior, satisfaction, or performance, through methods like analytics, metrics, or benchmarks.

6 Use continuous testing

Continuous testing is a holistic tool for testing rendering code, as it can help you integrate and automate all the other tools and methods, and ensure that your rendering code is always tested, validated, and updated. Continuous testing involves using tools like Jenkins, Travis CI, or CircleCI to set up a continuous integration and continuous delivery (CI/CD) pipeline, that runs your tests, builds your code, and deploys your code automatically, whenever you make a change. Continuous testing can help you reduce errors, bugs, and risks, and increase quality, speed, and reliability.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?