83 lines
No EOL
3 KiB
TeX
83 lines
No EOL
3 KiB
TeX
\section{Basic terms}
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\begin{frame}
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\centering
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\Huge
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Basic terms
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\end{frame}
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\subsection{Raytracing}
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\begin{frame}{Raytracing}
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\begin{center}
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\begin{minipage}{0.4\linewidth}
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\flushleft{} Turn 3D model...
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\includegraphics[width=\linewidth]{img/proseminar_workbench.png}
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\end{minipage}
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\pause{}
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$\rightarrow$
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\hspace{10mm}
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\begin{minipage}{0.4\linewidth}
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\flushright{} \ldots into a physically accurate image
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\includegraphics[width=0.8\linewidth]{proseminar_cycles.png}
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\end{minipage}
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\end{center}
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\end{frame}
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\begin{frame}{Raytracing}
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\begin{block}{Task}
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\begin{itemize}
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\item Determine the color of each Pixel in the scene
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\item Color (light intensity) is given by the rendering integral:\\
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\[
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\underbrace{I(x,x^{\prime})}_{\text{Light transport intensity from }x \text{ to } x^{\prime}}=
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\underbrace{g(x,x')}_{\text{geometry term}}
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\left[
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\underbrace{\epsilon(x,x')}_{\text{emissive light}}+\underbrace{\int_S \rho(x,x',x'')I(x',x'')dx''}_{\text{light scattered towards the point}}
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\right]
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\]
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%\begin{itemize}
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%\item Attempts to capture the physical light transport phenomenon in a single equation
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%\end{itemize}
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[\cite{ACM:rendering_equation}]
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\item Problem: This equation is not analytically solvable\\
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$\rightarrow$ Solve numerically using Monte-Carlo integration (i.e.\ raytracing)
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\end{itemize}
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\end{block}
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\end{frame}
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\begin{frame}{Raytracing}
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\setbeamercovered{transparent}
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\begin{block}{Principle (simplified)}
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\begin{itemize}
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\item Cast rays from the camera towards the scene
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\item Calculate geometry intersection
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\item Trace rays from intersection point to all light sources
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\item Calculate color from emission and the sampled reflected light, taking geometry into account (e.g.\ occlusion)
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\item Have the ray ``bounce around' to account for indirect lighting
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\end{itemize}
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\end{block}
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\pause{}
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\begin{block}{Variables}
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Scene depends on lots of variables:
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\begin{itemize}
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\item Material properties (roughness, emission strength, color, transmissiveness\ldots)
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\item Vertex positions
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\end{itemize}
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\end{block}
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\end{frame}
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\begin{frame}{Visualization}
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\input{diagrams/raytracing_anim}
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\end{frame}
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\begin{frame}{Image synthesis~-~optical phenomena}
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\centering
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\includegraphics[width=0.38\linewidth]{proseminar_cycles_annotated.png}
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\end{frame}
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\subsection{Differentiable rendering}
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\begin{frame}{Differentiable rendering}
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\begin{itemize}
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\item Given: Function mapping a 3D-scene to a real number (e.g.\ error function)
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\item Target: Calculate gradient of that function
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\item Required: Differentiate with respect to any scene parameter
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\end{itemize}
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\end{frame} |