public COLLIDE checkCollision(Vector2 pos, Vector2 vel)
{
Vector2 ptA, ptB; float dist;
var result = COLLIDE.NONE;
if (isBroken)
{
return(result);
}
// Check for collision with each edge
Vector2 vec;
// Bottom
ptA.x = x;
ptA.y = y + height;
ptB.x = x + width;
ptB.y = y + height;
if (vel.y < 0 && pos.y > ptA.y)
{
if (pos.x > ptA.x && pos.x < ptB.x)
{
dist = pos.y - ptA.y;
if (dist < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.DOWN;
}
}
else
{
vec = pos.x <= ptA.x ? pos - ptA : pos - ptB;
if (MathX.Fabs(vec.y) > MathX.Fabs(vec.x) && vec.LengthFast < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.DOWN;
}
}
}
if (result != COLLIDE.NONE)
{
return(result);
}
// Top
ptA.y = y;
ptB.y = y;
if (vel.y > 0 && pos.y < ptA.y)
{
if (pos.x > ptA.x && pos.x < ptB.x)
{
dist = ptA.y - pos.y;
if (dist < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.UP;
}
}
else
{
vec = pos.x <= ptA.x ? pos - ptA : pos - ptB;
if (MathX.Fabs(vec.y) > MathX.Fabs(vec.x) && vec.LengthFast < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.UP;
}
}
}
if (result != COLLIDE.NONE)
{
return(result);
}
// Left side
ptA.x = x;
ptA.y = y;
ptB.x = x;
ptB.y = y + height;
if (vel.x > 0 && pos.x < ptA.x)
{
if (pos.y > ptA.y && pos.y < ptB.y)
{
dist = ptA.x - pos.x;
if (dist < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.LEFT;
}
}
else
{
vec = pos.y <= ptA.y ? pos - ptA : pos - ptB;
if (MathX.Fabs(vec.x) >= MathX.Fabs(vec.y) && vec.LengthFast < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.LEFT;
}
}
}
if (result != COLLIDE.NONE)
{
return(result);
}
// Right side
ptA.x = x + width;
ptB.x = x + width;
if (vel.x < 0 && pos.x > ptA.x)
{
if (pos.y > ptA.y && pos.y < ptB.y)
{
dist = pos.x - ptA.x;
if (dist < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.LEFT;
}
}
else
{
vec = pos.y <= ptA.y ? pos - ptA : pos - ptB;
if (MathX.Fabs(vec.x) >= MathX.Fabs(vec.y) && vec.LengthFast < GameBustOutWindow.BALL_RADIUS)
{
result = COLLIDE.LEFT;
}
}
}
return(result);
}
public override float Evaluate(float[] state, float[] newState, float t0, float t1)
{
int i, n;
float max, error;
var delta = t1 - t0;
for (n = 0; n < 4; n++)
{
var halfDelta = delta * 0.5F;
var fourthDelta = delta * 0.25F;
float sixthDelta;
// first step of first half delta
derive(t0, userData, state, d1);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + fourthDelta * d1[i];
}
// second step of first half delta
derive(t0 + fourthDelta, userData, tmpState, d2);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + fourthDelta * d2[i];
}
// third step of first half delta
derive(t0 + fourthDelta, userData, tmpState, d3);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + halfDelta * d3[i];
}
// fourth step of first half delta
derive(t0 + halfDelta, userData, tmpState, d4);
sixthDelta = halfDelta * (1.0F / 6.0F);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + sixthDelta * (d1[i] + 2.0F * (d2[i] + d3[i]) + d4[i]);
}
// first step of second half delta
derive(t0 + halfDelta, userData, tmpState, d1half);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + fourthDelta * d1half[i];
}
// second step of second half delta
derive(t0 + halfDelta + fourthDelta, userData, tmpState, d2);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + fourthDelta * d2[i];
}
// third step of second half delta
derive(t0 + halfDelta + fourthDelta, userData, tmpState, d3);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + halfDelta * d3[i];
}
// fourth step of second half delta
derive(t0 + delta, userData, tmpState, d4);
sixthDelta = halfDelta * (1.0F / 6.0F);
for (i = 0; i < dimension; i++)
{
newState[i] = state[i] + sixthDelta * (d1[i] + 2.0F * (d2[i] + d3[i]) + d4[i]);
}
// first step of full delta
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + halfDelta * d1[i];
}
// second step of full delta
derive(t0 + halfDelta, userData, tmpState, d2);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + halfDelta * d2[i];
}
// third step of full delta
derive(t0 + halfDelta, userData, tmpState, d3);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + delta * d3[i];
}
// fourth step of full delta
derive(t0 + delta, userData, tmpState, d4);
sixthDelta = delta * (1.0F / 6.0F);
for (i = 0; i < dimension; i++)
{
tmpState[i] = state[i] + sixthDelta * (d1[i] + 2.0F * (d2[i] + d3[i]) + d4[i]);
}
// get max estimated error
max = 0.0F;
for (i = 0; i < dimension; i++)
{
error = MathX.Fabs((newState[i] - tmpState[i]) / (delta * d1[i] + 1e-10F));
if (error > max)
{
max = error;
}
}
error = max / maxError;
if (error <= 1.0f)
{
return(delta * 4.0F);
}
if (delta <= 1e-7F)
{
return(delta);
}
delta *= 0.25F;
}
return(delta);
}