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* Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
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* This software is provided 'as-is', without any express or implied
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* warranty. In no event will the authors be held liable for any damages
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* arising from the use of this software.
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* Permission is granted to anyone to use this software for any purpose,
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* including commercial applications, and to alter it and redistribute it
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* freely, subject to the following restrictions:
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* 1. The origin of this software must not be misrepresented; you must not
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* claim that you wrote the original software. If you use this software
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* in a product, an acknowledgment in the product documentation would be
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* appreciated but is not required.
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* 2. Altered source versions must be plainly marked as such, and must not be
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* misrepresented as being the original software.
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* 3. This notice may not be removed or altered from any source distribution.
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#ifndef B2_POLYGON_SHAPE_H
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#define B2_POLYGON_SHAPE_H
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#include <Box2D/Collision/Shapes/b2Shape.h>
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/// A convex polygon. It is assumed that the interior of the polygon is to
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/// the left of each edge.
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/// Polygons have a maximum number of vertices equal to b2_maxPolygonVertices.
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/// In most cases you should not need many vertices for a convex polygon.
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class b2PolygonShape : public b2Shape
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/// Implement b2Shape.
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b2Shape* Clone(b2BlockAllocator* allocator) const;
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/// @see b2Shape::GetChildCount
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int32 GetChildCount() const;
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/// Copy vertices. This assumes the vertices define a convex polygon.
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/// It is assumed that the exterior is the the right of each edge.
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/// The count must be in the range [3, b2_maxPolygonVertices].
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void Set(const b2Vec2* vertices, int32 vertexCount);
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/// Build vertices to represent an axis-aligned box.
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/// @param hx the half-width.
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/// @param hy the half-height.
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void SetAsBox(float32 hx, float32 hy);
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/// Build vertices to represent an oriented box.
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/// @param hx the half-width.
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/// @param hy the half-height.
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/// @param center the center of the box in local coordinates.
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/// @param angle the rotation of the box in local coordinates.
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void SetAsBox(float32 hx, float32 hy, const b2Vec2& center, float32 angle);
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/// @see b2Shape::TestPoint
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bool TestPoint(const b2Transform& transform, const b2Vec2& p) const;
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/// Implement b2Shape.
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bool RayCast(b2RayCastOutput* output, const b2RayCastInput& input,
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const b2Transform& transform, int32 childIndex) const;
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/// @see b2Shape::ComputeAABB
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void ComputeAABB(b2AABB* aabb, const b2Transform& transform, int32 childIndex) const;
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/// @see b2Shape::ComputeMass
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void ComputeMass(b2MassData* massData, float32 density) const;
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/// Get the vertex count.
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int32 GetVertexCount() const { return m_vertexCount; }
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/// Get a vertex by index.
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const b2Vec2& GetVertex(int32 index) const;
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b2Vec2 m_vertices[b2_maxPolygonVertices];
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b2Vec2 m_normals[b2_maxPolygonVertices];
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inline b2PolygonShape::b2PolygonShape()
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m_radius = b2_polygonRadius;
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inline const b2Vec2& b2PolygonShape::GetVertex(int32 index) const
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b2Assert(0 <= index && index < m_vertexCount);
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return m_vertices[index];