// Join similar adjacent line segments together. Works well for hard edged shapes.
// 'tol' is the minimum anglular difference in radians of a vertex.
cpPolyline *
cpPolylineSimplifyVertexes(cpPolyline *line, cpFloat tol)
{
cpPolyline *reduced = cpPolylineMake2(0, line->verts[0], line->verts[1]);
cpFloat minSharp = -cpfcos(tol);
for(int i=2; i<line->count; i++){
cpVect vert = line->verts[i];
cpFloat sharp = Sharpness(reduced->verts[reduced->count - 2], reduced->verts[reduced->count - 1], vert);
if(sharp <= minSharp){
reduced->verts[reduced->count - 1] = vert;
} else {
reduced = cpPolylinePush(reduced, vert);
}
}
if(
cpPolylineIsClosed(line) &&
Sharpness(reduced->verts[reduced->count - 2], reduced->verts[0], reduced->verts[1]) < minSharp
){
reduced->verts[0] = reduced->verts[reduced->count - 2];
reduced->count--;
}
// TODO shrink
return reduced;
}
cpVect
cpvforangle(const cpFloat a)
{
return cpv(cpfcos(a), cpfsin(a));
}
static cpSpace *
init(void)
{
staticBody = cpBodyNew(INFINITY, INFINITY);
cpResetShapeIdCounter();
space = cpSpaceNew();
space->elasticIterations = 0;
space->iterations = 5;
cpSpaceResizeStaticHash(space, 40.0f, 999);
cpSpaceResizeActiveHash(space, 30.0f, 2999);
cpShape *shape;
// add a non-collidable segment as a quick and dirty way to draw the query line
shape = cpSegmentShapeNew(staticBody, cpvzero, cpv(100.0f, 0.0f), 4.0f);
cpSpaceAddStaticShape(space, shape);
shape->layers = 0;
querySeg = shape;
{ // add a fat segment
cpFloat mass = 1.0f;
cpFloat length = 100.0f;
cpVect a = cpv(-length/2.0f, 0.0f), b = cpv(length/2.0f, 0.0f);
cpBody *body = cpSpaceAddBody(space, cpBodyNew(mass, cpMomentForSegment(mass, a, b)));
body->p = cpv(0.0f, 100.0f);
cpSpaceAddShape(space, cpSegmentShapeNew(body, a, b, 20.0f));
}
{ // add a static segment
cpSpaceAddStaticShape(space, cpSegmentShapeNew(staticBody, cpv(0, 300), cpv(300, 0), 0.0f));
}
{ // add a pentagon
cpFloat mass = 1.0f;
const int NUM_VERTS = 5;
cpVect verts[NUM_VERTS];
for(int i=0; i<NUM_VERTS; i++){
cpFloat angle = -2*(cpFloat)M_PI*i/((cpFloat) NUM_VERTS);
verts[i] = cpv(30*cpfcos(angle), 30*cpfsin(angle));
}
cpBody *body = cpSpaceAddBody(space, cpBodyNew(mass, cpMomentForPoly(mass, NUM_VERTS, verts, cpvzero)));
body->p = cpv(50.0f, 50.0f);
cpSpaceAddShape(space, cpPolyShapeNew(body, NUM_VERTS, verts, cpvzero));
}
{ // add a circle
cpFloat mass = 1.0f;
cpFloat r = 20.0f;
cpBody *body = cpSpaceAddBody(space, cpBodyNew(mass, cpMomentForCircle(mass, 0.0f, r, cpvzero)));
body->p = cpv(100.0f, 100.0f);
cpSpaceAddShape(space, cpCircleShapeNew(body, r, cpvzero));
}
return space;
}
