DREAM IDEA PLAN IMPLEMENTATION 1 2 Introduction to

DREAM IDEA PLAN IMPLEMENTATION 1

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Introduction to Computer Graphics Present to: Amirkabir University of Technology (Tehran Polytechnic) & Semnan University Dr. Kourosh Kiani Email: kkiani 2004@yahoo. com Email: Kourosh. kiani@aut. ac. ir Web: aut. ac. com 3

Amirkabir & Semnan University Computer & Electrical Faculty Lecture 09 3 D viewing 4

General 3 D Viewing Pipeline • • • 5 Modeling coordinates (MC) World coordinates (WC) Viewing coordinates (VC) Projection coordinates (PC) Normalized coordinates (NC) Device coordinates (DC)

Viewing-Coordinate Parameters • View point (eye point or viewing position) • View-plane normal vector N 6

Viewing-Coordinate Parameters • Look-at point Pref • View-up vector V – N and V are specified in the world coordinates – V should be perpendicular to N, but it can be difficult to a direction for V that is precisely perpendicular to N 7

Viewing-Coordinate Reference Frame • The camera orientation is determined by the uvn reference frame u v 8 n

World-to-Viewing Transformation • Transformation from world to viewing coordinates – Translate the viewing-coordinate origin to the world -coordinate origin – Apply rotations to align the u, v, n axes with the world xw, yw, zw axes, respectively u v 9 n

World-to-Viewing Transformation 10

Normalizing Transformation • Transform an arbitrary perspective-projection view volume into the canonical view volume • Step 1: from frustum to parallelepiped 11

Normalizing Transformation • Transform an arbitrary perspective-projection view volume into the canonical view volume • Step 2: from parallelepiped to normalized 12

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Questions? Discussion? Suggestions ?

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