October 2024
Intermediate
240 pages
6h 57m
Japanese
Content preview from 図解まるわかり VR・AR・MRのしくみ
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
136
LOD
遠近感によるモデル精度を
自動調整
6-6
精度を自動調整することでリアルな遠近感
リアルな3D表現に重要な遠近感ですが、追求するあまり多くのポリゴ
ンや高解像度のテクスチャを使用すると、見た目の精度は向上しますが、
データのサイズが大きくなり、処理に時間がかかってしまいます。
遠近感をうまく表現するためには、3Dモデルの精度を自動的に調整で
きる技術が必要です。具体的には、遠くから見た物体は簡略化された精度
で、近くから見た物体は高い精度で自動的に調節するといったように、効
率的な描画手法の採用が不可欠なのです（図6-11）。
LODでクオリティはそのままに軽量化
そこで有能なのが、LOD（LevelofDetail）です。LODとは、視点から
の距離に応じて3D モデルの精度を自動的に調整する技術です。
視点に近いオブジェクトにはポリゴン数も多くテクスチャも高精度のモ
デルを適用し、視点から離れたオブジェクトには低精度のモデルを使用し
ます（図6-12）。この調整により、リアルな遠近感を保ちながらも、処理
に必要な計算量を減らし、描画の効率と表現の滑らかさを向上させること
が可能です。
XRアプリケーションやゲームに採用されるLOD
LODを採用すれば、3D表現において多数の物体を効率的に描画するこ
とができるようになります。身近なXRアプリケーションやゲームにおい
てLODは広く使用されており、フライトシミュレーターや地図アプリケ
ーションなど、多岐にわたる3D画像システムでも幅広く採用される汎用 ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.