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	demo.design 3D programming FAQ

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ÐÀÇÍÎÅ<br>7.2. Ñóáòåêñåëüíàÿ òî÷íîñòü

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<p>Ñóáòåêñåëüíàÿ òî÷íîñòü ñèëüíî ñìàõèâàåò íà ñóáïèêñåëüíóþ. Íåîáõîäèìîñòü â íåé
ïîÿâëÿåòñÿ èç-çà ñëåäóþùåãî ôàêòà: ðèñîâàòü ñòðîêó ìû íà÷èíàåì ñ êàêîãî-òî
íåöåëîãî sx, íî ñ öåëîãî ïèêñåëà. Èç-çà ýòîãî (sx ìîæåò "ãóëÿòü" â ïðåäåëàõ
îäíîãî ïèêñåëà ïî÷òè íà åäèíèöó!) âîçíèêàåò äðîæàíèå òåêñòóð ïðèìåðíî íà òîò
ñàìûé ïèêñåë. Óñòðàíÿåòñÿ ýòî òî÷íî òàêèì æå ñäâèãîì, êàê è â ñóáïèêñåëüíîé
òî÷íîñòè, òî åñòü ïåðåä îòðèñîâêîé ñòðîêè êîððåêòèðóþòñÿ íà÷àëüíûå çíà÷åíèÿ
âåëè÷èí, èíòåðïîëèðóåìûõ ïî ñòðîêå (u, v, îñâåùåííîñòü...):

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// ...
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<p>Ýòî óæå íåìíîãî çàìåäëÿåò ðàáîòó (íà âåëè÷èíó ïîðÿäêà 5-10%), íî óëó÷øåíèå
êà÷åñòâà êàðòèíêè òîãî ñòîèò. Êðîìå òîãî, ñóáòåêñåëüíóþ òî÷íîñòü âïîëíå ìîæíî
ñîâìåñòèòü ñ 2D-îòñå÷åíèåì è ïîëó÷èòü îòñå÷åíèå, êîòîðîå íå ñúåäàåò íèêàêèõ
ðåñóðñîâ è íå çàìåäëÿåò ðàáîòó. Âîîáùå.

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