Chapter 10. Trigonometric and Geometric Functions

In this chapter

  • Calculating Point and Line Intersections

  • Calculating Slope

  • Calculating Point and Arc Intersections

  • Next Steps

Chapter 9,"Object Bounds Checking," showed the necessity of accurately selecting graphic objects created by the editor and the frailty of using solely the bounds of the object for making the determination of selection. This chapter reviews the mathematics required for a more precise selection algorithm.

Chapter 9 discussed the objects of the editor as being point-array–based or as being an arc. We first consider the intersection of a point and a line.

Calculating Point and Line Intersections

Objects created by our editor that are defined as an array of points can be ...

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