17 lines
998 B
Markdown
17 lines
998 B
Markdown
---
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title: "Overview"
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date: 2019-09-14T19:19:03-07:00
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weight: 5
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---
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In Bonk, an **IShape2D** is defined by two methods.
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1) A *support function*, which is a method that returns the farthest possible point in the shape in a given **Vector2** direction. The shape vertices are transformed by a **Transform2D**.
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2) A method for creating an axis-aligned bounding box from the shape that takes a **Transform2D** to transform the shape vertices.
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Bonk provides you with tested implementations of four common 2D shapes, but you can implement these methods to create custom **IShape2D** structs.
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Note that shapes themselves do not contain absolute position data. You will use a **Transform2D** to manipulate the shape's position, rotation, and scale in 2D space.
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A final restriction to note: Defining concave shapes is an error. The collision solving algorithm that Bonk uses does not support concave shapes. If you wish to define concave shapes, define them as a composition of multiple convex shapes. |