TOTAL RECAP INFOGR Computer Graphics Jacco Bikker & Debabrata - PowerPoint PPT Presentation

TOTAL RECAP

INFOGR – Computer Graphics Jacco Bikker & Debabrata Panja - April-July 2018 Lecture 15: “Grand Recap” Welcome!

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 4: Graphics Fundamentals Conc oncepts: Raster, discretization, anti-aliasing, rasterization, frame rate, vertical retrace, ‘frame - less’, RGB colors, 16 -bit, palletized, HDR. Questions? ▪ Where does the name ‘retrace’ come from? ▪ What is ‘ vsync ’? ▪ What is the difference between discretization and rasterization? ▪ What is the frame rate of the human eye? ▪ How many bits do we spend on red, green and blue in 16-bit colors, and why? ▪ Do you have to use floats for HDR? ▪ What is anti-aliasing? ▪ When is 240fps on a 60Hz monitor useful?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 4, part 2 – Ray Tracing Intro Conc oncepts: The “God Algorithm”: light transport in nature, light transport in a ray tracer, ray tracing versus rasterization, convex / concave, reflection and shadows in a rasterizer, global data, ray optics, refraction, reflection, Fresnel, Snell, Whitted-style (recursive) ray tracing, ray equation, ray setup, normalization, ray/plane intersection, ray/sphere intersection, primary rays, shadow rays, shadow acne, distance attenuation, absorption, N dot L. Questions? ▪ Can a triangle be concave? ▪ What is ‘Fresnel’, and who is ‘ Schlick ’? ▪ What is ‘Snell’s law’? ▪ What is a ‘refraction index’? Is 8.1 a reasonable refraction index? What about 0.1? ▪ What is Whitted-style ray tracing? ▪ What causes shadow acne? ▪ Why do we calculate N dot L?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 4, part 2 – Ray Tracing Intro Ma Make sure you can can: ▪ Explain why the efficient ray/sphere intersection code on slide 30 will not work for glass spheres; ▪ Setup a proper ray given a view direction, FOV and up vector; ▪ Explain why you need an up vector. ▪ How is the ‘up vector’ used when setting up a ‘ lookAt ’ matrix? ▪ How do you define the ‘up’ vector on one of those curvy Mario tracks?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 5 – Ray Tracing Conc oncepts: Calculating normals, vertex normal, normal interpolation, normal for a plane and a sphere, partially reflective surfaces, HDR sky dome, ray tree, diffuse material, Lambert, glossy, Phong, dielectrics, limitations of Whitted-style ray tracing. Questions? ▪ How can a vertex have a normal? ▪ How does one ‘Interpolate a normal’? ▪ What is the ‘ray tree’? ▪ What or who is Phong? ▪ Name something Whitted- style ray tracing can’t do.

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 6 – Ray Tracing (2) Ma Make sure you can can: ▪ Construct a vector reflected in a plane; ▪ Explain why a bathroom mirror is (close to) white; ▪ Explain why we need a cap on recursion; ▪ Explain why rays transport little energy in a deep ray tree; Questions? ▪ Write down the equation that reflects a vector in a plane defined by a normal vector. ▪ How does one ‘Interpolate a normal’? ▪ What is the ‘ray tree’? ▪ What or who is Phong? ▪ Name something Whitted-style ray tracing can’t do.

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 7 – Accelerate Conc oncepts: AABB, culling, bounding volume hierarchy, conservative tests, false negatives, early out, precalculate, loop hoisting, incremental rendering, rasterization, z-buffer, global data, slab test, ray tracing versus rasterization, spaces, scene graph, engine design. Make sure you can Ma can: ▪ Construct an AABB for a triangle, sphere, mesh, … ; ▪ Intersect a ray and a triangle; ▪ Intersect a ray and an AABB using the slab test; ▪ Cull a sphere and an AABB against a frustum. Questions?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 11: OpenGL Conc oncepts: OpenGL, ARGB, Khronos Group, Fahrenheit, Glide, 3dfx, VooDoo, HW T&L, OpenGL coordinate system, right handed, immediate mode, retained mode, state machine, GPU, streaming processor, caches, GPU model, state changes, vertex buffer objects, pixel shader, vertex shader. Questions? ▪ What is the relation between Vulkan, Khronos, Mantle and OpenGL? ▪ Why is z negative when going into the screen? ▪ What is a near clipping plane, and why do we need it? ▪ What is a state machine? ▪ Why don’t we run Windows on a GPU? ▪ What is the purpose of a vertex shader? ▪ What is ‘retained mode’? ▪ What is a ‘fixed function pipeline’?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 12: Shaders Conc oncepts: World space, camera space, model space, uniform variables, glossy, Phong, Phong exponent, ambient, planar reflections, environment maps, normal maps, tangent space, fur shells. Questions? ▪ What is the purpose of the ‘ambient’ color in Phong? ▪ What does the exponent in Phong do? ▪ How is fur rendered? ▪ How is a reflective lake simulated in a rasterizer? ▪ What is an ‘environment map’, and what are the limitations of the technique? ▪ What is ‘tangent space’? ▪ Why is a normal map mostly blue? ▪ Why do we not need to store z for a normal map?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 13: Visibility Conc oncepts: Painter’s, overdraw, BSP traversal (back -to-front, front-to-back), z-buffer, values in the z-buffer, z-fighting, Sutherland-Hodgeman clipping, n-gons, guard bands, back-face culling, frustum culling, hierarchical bounding volume culling, culling using a grid, portals: visibility, mirrors, ‘portals’. ▪ What is ‘overdraw’? Can it be completely prevented? ▪ Why would you want to store 1/z instead of z? ▪ How do you ‘ backface cull’? ▪ Questions? What is a ‘portal’? ▪ How do you clip a polygon? ▪ What is z-fighting?

INFOGR – Lecture 15 – “Grand Recap” RECAP Lecture 14: Post Processing Conc oncepts: Post processing, camera / sensor behavior, lens flares, vignetting, chromatic aberration, noise / grain, HDR bloom and glare, tone mapping / exposure control, color correction / grading, gamma, gamma correction, depth of field, circle of confusion, ambient occlusion, screen space AO, bilateral filtering, screen space reflections, limitations of screen space approaches. ▪ What causes chromatic aberration in Questions? a real camera? ▪ How do you calculate HDR bloom? ▪ How is a color cube used for color correction? ▪ What is the ‘circle of confusion’? ▪ Name two limitations of screen space reflections. ▪ What quantity do you calculate for ambient occlusion?

INFOGR – Lecture 15 – “Grand Recap” RECAP TOTAL RECAP

INFOGR – Lecture 15 – “Grand Recap” What’s Next? Upcoming Attractions: ▪ Final Exam: Thursday June 28, 13:30 ▪ P3 deadline: Tuesday June 26, 23:59 ▪ Retake Exam: Thursday July 12, 13:30 This afternoon: ▪ Final practical + math questions Master: Bachelor: ▪ Optimization & Vectorization ▪ Concurrency ▪ Advanced Graphics

INFOGR – Computer Graphics Jacco Bikker - April-July 2018 - Lecture 14: “Grand Recap” THE END next up: “Final Exam” CARACAL

INFOGR