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Velocity Raptor is a 2D physics engine for games.
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2D physics engine, written in highly portable C, with no dependencies other than the standard library. Designed to be fast, stable and accurate. Velocity Raptor is free to use in commercial and non-commercial applications.

It features Collision detection for convex polygons with the Separate Axis Theorum, and it can support concanve shapes, by using ear clipping to turn concave shapes into triangles. Collision's are resolved with impulses, and for bodies with two contacts, a mini-block solver will solve them together. The engine is completely ready for use (but still in development), however it has yet to be documented so you may have to dig through the source code. Units are in pixels.

##Projects Using Velocity Raptor Crown Room

Chicken Coup

Topdown Shooter

##Velocity Raptor Demo videos Velocity Raptor Benchmark and Joints

Velocity Raptor Fluids

Velocity Raptor concave and composite polyons


To create a world:

vrWorld* world = vrWorldInit(vrWorldAlloc());
world->gravity = vrVect(0, 9.81);

To add a body:

vrRigidBody* body = vrBodyInit(vrBodyAlloc());
body->bodyMaterial.mass = 5;
body->bodyMaterial.invMass = 1.0 / body->bodyMaterial.mass;
body->bodyMaterial.momentInertia = vrMomentForBox(10, 10, body->bodyMaterial.mass);
body->bodyMaterial.invMomentInertia = 1.0 / body->bodyMaterial.momentInertia;
body->bodyMaterial.friction = 0.01;
body->bodyMaterial.restitution = 0.2;
vrWorldAddBody(world, body);

To add a box shape:

vrShape* shape = vrShapeInit(vrShapeAlloc());
shape = vrShapePolyInit(shape);
shape->shape = vrPolyBoxInit(shape->shape, x, y, w, h);
vrArrayPush(body->shape, shape);

To add a polygon shape:

vrShape* shape = vrShapeInit(vrShapeAlloc());
shape = vrShapePolyInit(shape);
vrAddVertexToPolyShape(shape->shape, vrVect(0, 0));
vrAddVertexToPolyShape(shape->shape, vrVect(10, 0));
vrAddVertexToPolyShape(shape->shape, vrVect(10, 10));
vrAddVertexToPolyShape(shape->shape, vrVect(0, 10));
vrArrayPush(body->shape, shape);

To add a circle shape:

vrShape* shape = vrShapeInit(vrShapeAlloc());
shape = vrShapeCircleInit(shape);
shape->shape = vrCircleInit(shape->shape);
vrCircleShape* circle = shape->shape;
circle->center = vrVect(0, 0);
circle->radius = 25;
vrArrayPush(body->shape, shape);

Every tick, call this to update the world:


To clean up, and free all memory:


To remove a body from the world and free its memory before destruction of world

vrWorldRemoveBody(world, body);
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