9 - Geometry Review

ucla | CS 174A | 2024-03-18 20:53

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Table of Contents

• Plane Equations
• Collinearity
• Edge-Edge Intersection
• Point in Polygon

Plane Equations

Collinearity

Edge-Edge Intersection

Point in Polygon

• for ray:
  • draw an infinite ray horizontally to the right of the point in question, odd # of intersections => point in polygon, even => outside polygon
• angle summation:
  • draw vectors from point to all vertices of the polygon, count angles between these drawn vectors
  • if sum = 360 => inside polygon