透視投影








透視投影（とうしとうえい、英: perspective projection）とは、3次元の物体を見たとおりに2次元平面に描画するための図法（レンダリング手法）である。これによって得られた図は「透視図」「投影図」あるいは英語の perspective から「パース」などと呼ばれる。


透視投影は幾何学的な手続きに基づいて行われる。その図法には1点透視図法、2点透視図法などがある（詳細は遠近法を参照のこと）。



絵画芸術における透視投影




透視投影


写真はカメラの位置に応じて適切に遠近法が適用される。正確な透視投影を使った絵を描きたければ、写真の輪郭をなぞることが手っ取り早い。写真とは異なる大きさの絵を描く場合は、比例コンパス（バリスケーラーとも）を利用すれば、正確な比率の縮尺図を描くことが出来る。



3次元コンピュータグラフィックスにおける透視投影


3DCGの基本原理も透視投影によるものである。詳細は「3次元コンピュータグラフィックス#原理」を参照。




透視投影によるワイヤーフレームで描いた前方後円墳(仲津山古墳)





平行投影によるワイヤーフレームで描いた同じ前方後円墳。
手前と奥の大きさの違い、縦方向の格子の開き方の違いに注目。



関連項目



  • 遠近法

  • 投影法

  • 投影図

  • 平行投影

  • 作図

  • 射影幾何学




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