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// MIT License
// Copyright (c) 2019 Erin Catto
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
#ifndef B2_POLYGON_SHAPE_H
#define B2_POLYGON_SHAPE_H
#include "b2_api.h"
#include "b2_shape.h"
/// A solid convex polygon. It is assumed that the interior of the polygon is to
/// the left of each edge.
/// Polygons have a maximum number of vertices equal to b2_maxPolygonVertices.
/// In most cases you should not need many vertices for a convex polygon.
class B2_API b2PolygonShape : public b2Shape
{
public:
b2PolygonShape();
/// Implement b2Shape.
b2Shape* Clone(b2BlockAllocator* allocator) const override;
/// @see b2Shape::GetChildCount
int32 GetChildCount() const override;
/// Create a convex hull from the given array of local points.
/// The count must be in the range [3, b2_maxPolygonVertices].
/// @warning the points may be re-ordered, even if they form a convex polygon
/// @warning collinear points are handled but not removed. Collinear points
/// may lead to poor stacking behavior.
void Set(const b2Vec2* points, int32 count);
/// Build vertices to represent an axis-aligned box centered on the local origin.
/// @param hx the half-width.
/// @param hy the half-height.
void SetAsBox(float hx, float hy);
/// Build vertices to represent an oriented box.
/// @param hx the half-width.
/// @param hy the half-height.
/// @param center the center of the box in local coordinates.
/// @param angle the rotation of the box in local coordinates.
void SetAsBox(float hx, float hy, const b2Vec2& center, float angle);
/// @see b2Shape::TestPoint
bool TestPoint(const b2Transform& transform, const b2Vec2& p) const override;
/// Implement b2Shape.
/// @note because the polygon is solid, rays that start inside do not hit because the normal is
/// not defined.
bool RayCast(b2RayCastOutput* output, const b2RayCastInput& input,
const b2Transform& transform, int32 childIndex) const override;
/// @see b2Shape::ComputeAABB
void ComputeAABB(b2AABB* aabb, const b2Transform& transform, int32 childIndex) const override;
/// @see b2Shape::ComputeMass
void ComputeMass(b2MassData* massData, float density) const override;
/// Validate convexity. This is a very time consuming operation.
/// @returns true if valid
bool Validate() const;
b2Vec2 m_centroid;
b2Vec2 m_vertices[b2_maxPolygonVertices];
b2Vec2 m_normals[b2_maxPolygonVertices];
int32 m_count;
};
inline b2PolygonShape::b2PolygonShape()
{
m_type = e_polygon;
m_radius = b2_polygonRadius;
m_count = 0;
m_centroid.SetZero();
}
#endif
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