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Mathematical Optimization in Graphics and Vision - Luiz Velho - Impa

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Chapter 3<br />

<strong>Optimization</strong> <strong>and</strong> computer<br />

graphics<br />

In this chapter we will show the importance of optimization methods <strong>in</strong> computer<br />

graphics. We will pose several problems <strong>in</strong> the area, whose solutions use<br />

optimization techniques. The problems we will pose here will be solved <strong>in</strong> the<br />

follow<strong>in</strong>g chapters with the appropriate optimization technique: cont<strong>in</strong>uous, discrete,<br />

comb<strong>in</strong>atorial or variational.<br />

3.1 A unified view of computer graphics problems<br />

Computer graphics problems are, <strong>in</strong> general, posed by consider<strong>in</strong>g two spaces O 1<br />

<strong>and</strong> O 2 of graphical objects, <strong>and</strong> relations between them. 1 In several practical<br />

situations, the spaces O 1 <strong>and</strong> O 2 are topological spaces <strong>and</strong> the relation is an<br />

operator (i.e. a cont<strong>in</strong>uous function) from O 1 to O 2 . An even more well behaved<br />

condition occurs when O 1 <strong>and</strong> O 2 are vector spaces <strong>and</strong> the operator is l<strong>in</strong>ear.<br />

We will consider the <strong>in</strong>termediate case when we have two topological spaces<br />

of graphical objects O 1 <strong>and</strong> O 2 , <strong>and</strong> an operator R: O 1 → O 2 from O 1 to O 2 .<br />

From this we have the follow<strong>in</strong>g generic problems:<br />

• For a given graphical object x ∈ O 1 , compute T (x) (direct problem);<br />

1 A relation is a subset of the cartesian product O 1 × O 2 .<br />

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