public void StartImpulseObject()
{
if (started)
{
return;
}
verts = Vec2.ArrayOf(activePoints.Length);
for (int v = 0; v < activePoints.Length; v++)
{
verts[v].x = activePoints[v].x;
verts[v].y = activePoints[v].y;
}
body = impulse.Add(new Polygon(verts), transform.position.x, transform.position.y);
body.SetOrient(0);
body.restitution = 0.2f;
body.dynamicFriction = 0.2f;
body.staticFriction = 0.4f;
shape = ((Polygon)body.shape);
started = true;
}
public override void HandleCollision(Manifold m, Body a, Body b)
{
Polygon A = (Polygon)a.shape;
Polygon B = (Polygon)b.shape;
m.contactCount = 0;
// Check for a separating axis with A's face planes
int[] faceA = { 0 };
float penetrationA = FindAxisLeastPenetration(faceA, A, B);
if (penetrationA >= 0.0f)
{
return;
}
// Check for a separating axis with B's face planes
int[] faceB = { 0 };
float penetrationB = FindAxisLeastPenetration(faceB, B, A);
if (penetrationB >= 0.0f)
{
return;
}
int referenceIndex;
bool flip; // Always point from a to b
Polygon RefPoly; // Reference
Polygon IncPoly; // Incident
// Determine which shape contains reference face
if (ImpulseMath.Gt(penetrationA, penetrationB))
{
RefPoly = A;
IncPoly = B;
referenceIndex = faceA[0];
flip = false;
}
else
{
RefPoly = B;
IncPoly = A;
referenceIndex = faceB[0];
flip = true;
}
// World space incident face
Vec2[] incidentFace = Vec2.ArrayOf(2);
FindIncidentFace(incidentFace, RefPoly, IncPoly, referenceIndex);
// y
// ^ .n ^
// +---c ------posPlane--
// x < | i |\
// +---+ c-----negPlane--
// \ v
// r
//
// r : reference face
// i : incident poly
// c : clipped point
// n : incident normal
// Setup reference face vertices
Vec2 v1 = RefPoly.vertices[referenceIndex];
referenceIndex = referenceIndex + 1 == RefPoly.vertexCount ? 0 : referenceIndex + 1;
Vec2 v2 = RefPoly.vertices[referenceIndex];
// Transform vertices to world space
// v1 = RefPoly->u * v1 + RefPoly->body->position;
// v2 = RefPoly->u * v2 + RefPoly->body->position;
v1 = RefPoly.u.Mul(v1).Addi(RefPoly.body.position);
v2 = RefPoly.u.Mul(v2).Addi(RefPoly.body.position);
// Calculate reference face side normal in world space
// Vec2 sidePlaneNormal = (v2 - v1);
// sidePlaneNormal.Normalize( );
Vec2 sidePlaneNormal = v2.Sub(v1);
sidePlaneNormal.Normalize();
// Orthogonalize
// Vec2 refFaceNormal( sidePlaneNormal.y, -sidePlaneNormal.x );
Vec2 refFaceNormal = new Vec2(sidePlaneNormal.y, -sidePlaneNormal.x);
// ax + by = c
// c is distance from origin
// real refC = Dot( refFaceNormal, v1 );
// real negSide = -Dot( sidePlaneNormal, v1 );
// real posSide = Dot( sidePlaneNormal, v2 );
float refC = Vec2.Dot(refFaceNormal, v1);
float negSide = -Vec2.Dot(sidePlaneNormal, v1);
float posSide = Vec2.Dot(sidePlaneNormal, v2);
// Clip incident face to reference face side planes
// if(Clip( -sidePlaneNormal, negSide, incidentFace ) < 2)
if (Clip(sidePlaneNormal.Neg(), negSide, incidentFace) < 2)
{
return; // Due to floating point error, possible to not have required
// points
}
// if(Clip( sidePlaneNormal, posSide, incidentFace ) < 2)
if (Clip(sidePlaneNormal, posSide, incidentFace) < 2)
{
return; // Due to floating point error, possible to not have required
// points
}
// Flip
m.normal.Set(refFaceNormal);
if (flip)
{
m.normal.Negi();
}
// Keep points behind reference face
int cp = 0; // clipped points behind reference face
float separation = Vec2.Dot(refFaceNormal, incidentFace[0]) - refC;
if (separation <= 0.0f)
{
m.contacts[cp].Set(incidentFace[0]);
m.penetration = -separation;
++cp;
}
else
{
m.penetration = 0;
}
separation = Vec2.Dot(refFaceNormal, incidentFace[1]) - refC;
if (separation <= 0.0f)
{
m.contacts[cp].Set(incidentFace[1]);
m.penetration += -separation;
++cp;
// Average penetration
m.penetration /= cp;
}
m.contactCount = cp;
}
void InputImpulseEngine(CommonMonoBehaviour.GameInput input)
{
if (!playing)
{
return;
}
if (input.keyDown[0])
{
playing = false;
}
if (input.keyDown[1])
{
if (input.mouseUp[0] || input.mouseDown[0])
{
float hw = ImpulseMath.Random(1.0f, 3.0f);
float hh = ImpulseMath.Random(1.0f, 3.0f);
Body b = impulse.Add(new Polygon(hw, hh), input.rayPosition.x, input.rayPosition.y);
b.SetOrient(0.0f);
}
if (input.mouseUp[1] || input.mouseDown[1])
{
float r = ImpulseMath.Random(1.0f, 5.0f);
int vertCount = 3;
Vec2[] verts = Vec2.ArrayOf(vertCount);
for (int i = 0; i < vertCount; i++)
{
verts[i].Set(ImpulseMath.Random(-r, r), ImpulseMath.Random(-r, r));
}
Body b = impulse.Add(new Polygon(verts), input.rayPosition.x, input.rayPosition.y);
b.SetOrient(ImpulseMath.Random(-ImpulseMath.PI, ImpulseMath.PI));
b.restitution = 0.2f;
b.dynamicFriction = 0.2f;
b.staticFriction = 0.4f;
}
}
else
{
if (input.mouseUp[0] || input.mouseDown[0])
{
float r = ImpulseMath.Random(1.0f, 5.0f);
int vertCount = ImpulseMath.Random(3, Polygon.MAX_POLY_VERTEX_COUNT);
Vec2[] verts = Vec2.ArrayOf(vertCount);
for (int i = 0; i < vertCount; i++)
{
verts[i].Set(ImpulseMath.Random(-r, r), ImpulseMath.Random(-r, r));
}
Body b = impulse.Add(new Polygon(verts), input.rayPosition.x, input.rayPosition.y);
b.SetOrient(ImpulseMath.Random(-ImpulseMath.PI, ImpulseMath.PI));
b.restitution = 0.2f;
b.dynamicFriction = 0.2f;
b.staticFriction = 0.4f;
}
if (input.mouseUp[1] || input.mouseDown[1])
{
float r = ImpulseMath.Random(1.0f, 3.0f);
impulse.Add(new Circle(r), input.rayPosition.x, input.rayPosition.y);
}
//Move your cube GameObject to the point where you clicked
if (PointerTransform)
{
PointerTransform.position = input.rayPosition;
}
}
}
