OpenGL Study Guide 2026
Everything you need to pass the OpenGL exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 OpenGL Exam Format at a Glance
📚 OpenGL Topics to Study (21)
✍️ Sample OpenGL Questions & Answers
1. What is the purpose of the GLSL normalize() function?
normalize(v) divides a vector by its magnitude, returning a direction vector of length 1.
2. Which OpenGL face culling mode keeps only front-facing triangles?
glCullFace(GL_BACK) combined with glEnable(GL_CULL_FACE) discards back-facing triangles, the most common culling setup.
3. What does the ARB suffix in an OpenGL extension name indicate?
ARB extensions are cross-vendor and vetted by the Architecture Review Board; they often become core features in future OpenGL versions.
4. What OpenGL blending equation produces standard over-compositing for transparent objects?
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA) blends source and destination by the fragment's alpha, the standard transparency blend.
5. What is the purpose of glPolygonMode(GL_FRONT_AND_BACK, GL_LINE) in OpenGL?
GL_LINE polygon mode rasterizes only polygon edges as lines, commonly used for debugging mesh topology.
6. Which OpenGL function sets the depth range mapping from NDC z to window z?
glDepthRange(near, far) remaps the NDC z range [-1, 1] to a custom window-space depth range, defaulting to [0, 1].