Современное состояние методов расчёта глобальной освещённости в задачах реалистичной компьютерной графики

Современная реалистичная компьютерная графика базируется на физически корректном моделировании распространения света. Одной из основных и трудно вычислимых задач при этом является расчет глобальной освещенности, т.е. распределения света в виртуальной сцене, учитывающий множественные отражения и рассеяния света и всевозможные виды взаимодействия его с объектами сцены. Этой проблеме посвящены сотни публикаций, описывающие десятки методов вычисления глобальной освещенности и их модификации. В данной обзорной статье мы бы хотели не просто перечислить и кратко описать эти методы, но и дать некоторую «карту» существующих работ, которая позволит читателю сориентироваться, понять их достоинства и недостатки и, тем самым, выбрать для себя подходящий базовый метод. Особое внимание уделяется таким характеристикам методов как надёжность и универсальность в отношении используемых моделей, прозрачность их верификации, возможность эффективной реализации на GPU, а также накладываемые на сцену или феномены освещённости ограничения. В отличие от существующих обзорных работ анализируется не только эффективность методов, но также их ограничения и сложность программной реализации. Кроме того, мы предоставляем результаты собственных численных экспериментов с различными методами, служащих иллюстрациями к выводам.

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