1/*
2* Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
3*
4* This software is provided 'as-is', without any express or implied
5* warranty. In no event will the authors be held liable for any damages
6* arising from the use of this software.
7* Permission is granted to anyone to use this software for any purpose,
8* including commercial applications, and to alter it and redistribute it
9* freely, subject to the following restrictions:
10* 1. The origin of this software must not be misrepresented; you must not
11* claim that you wrote the original software. If you use this software
12* in a product, an acknowledgment in the product documentation would be
13* appreciated but is not required.
14* 2. Altered source versions must be plainly marked as such, and must not be
15* misrepresented as being the original software.
16* 3. This notice may not be removed or altered from any source distribution.
17*/
18
19#ifndef B2_TIME_OF_IMPACT_H
20#define B2_TIME_OF_IMPACT_H
21
22#include <Box2D/Common/b2Math.h>
23#include <Box2D/Collision/b2Distance.h>
24
25/// Input parameters for b2TimeOfImpact
26struct b2TOIInput
27{
28 b2DistanceProxy proxyA;
29 b2DistanceProxy proxyB;
30 b2Sweep sweepA;
31 b2Sweep sweepB;
32 float32 tMax; // defines sweep interval [0, tMax]
33};
34
35// Output parameters for b2TimeOfImpact.
36struct b2TOIOutput
37{
38 enum State
39 {
40 e_unknown,
41 e_failed,
42 e_overlapped,
43 e_touching,
44 e_separated
45 };
46
47 State state;
48 float32 t;
49};
50
51/// Compute the upper bound on time before two shapes penetrate. Time is represented as
52/// a fraction between [0,tMax]. This uses a swept separating axis and may miss some intermediate,
53/// non-tunneling collision. If you change the time interval, you should call this function
54/// again.
55/// Note: use b2Distance to compute the contact point and normal at the time of impact.
56void b2TimeOfImpact(b2TOIOutput* output, const b2TOIInput* input);
57
58#endif
59