void PhysicsDebugDraw::drawShape(PhysicsShape& shape)
{
const Color4F fillColor(1.0f, 0.0f, 0.0f, 0.3f);
const Color4F outlineColor(1.0f, 0.0f, 0.0f, 1.0f);
for (auto it = shape._cpShapes.begin(); it != shape._cpShapes.end(); ++it)
{
cpShape *subShape = *it;
switch ((*it)->klass_private->type)
{
case CP_CIRCLE_SHAPE:
{
float radius = PhysicsHelper::cpfloat2float(cpCircleShapeGetRadius(subShape));
Vec2 centre = PhysicsHelper::cpv2point(cpBodyGetPos(cpShapeGetBody(subShape)));
Vec2 offset = PhysicsHelper::cpv2point(cpCircleShapeGetOffset(subShape));
Vec2 rotation(PhysicsHelper::cpv2point(cpBodyGetRot(cpShapeGetBody(subShape))));
centre += offset.rotate(rotation);
static const int CIRCLE_SEG_NUM = 12;
Vec2 seg[CIRCLE_SEG_NUM] = {};
for (int i = 0; i < CIRCLE_SEG_NUM; ++i)
{
float angle = (float)i * M_PI / (float)CIRCLE_SEG_NUM * 2.0f;
Vec2 d(radius * cosf(angle), radius * sinf(angle));
seg[i] = centre + d;
}
_drawNode->drawPolygon(seg, CIRCLE_SEG_NUM, fillColor, 1, outlineColor);
break;
}
case CP_SEGMENT_SHAPE:
{
cpSegmentShape *seg = (cpSegmentShape *)subShape;
_drawNode->drawSegment(PhysicsHelper::cpv2point(seg->ta),
PhysicsHelper::cpv2point(seg->tb),
PhysicsHelper::cpfloat2float(seg->r==0 ? 1 : seg->r), outlineColor);
break;
}
case CP_POLY_SHAPE:
{
cpPolyShape* poly = (cpPolyShape*)subShape;
int num = poly->numVerts;
Vec2* seg = new (std::nothrow) Vec2[num];
PhysicsHelper::cpvs2points(poly->tVerts, seg, num);
_drawNode->drawPolygon(seg, num, fillColor, 1.0f, outlineColor);
delete[] seg;
break;
}
default:
break;
}
}
}
float PhysicsShapeCircle::calculateDefaultMoment()
{
auto shape = _cpShapes.front();
return _mass == PHYSICS_INFINITY ? PHYSICS_INFINITY
: PhysicsHelper::cpfloat2float(cpMomentForCircle(_mass,
0,
cpCircleShapeGetRadius(shape),
cpCircleShapeGetOffset(shape)));
}
float PhysicsShapeCircle::calculateDefaultMoment()
{
cpShape* shape = _info->getShapes().front();
return _mass == PHYSICS_INFINITY ? PHYSICS_INFINITY
: PhysicsHelper::cpfloat2float(cpMomentForCircle(PhysicsHelper::float2cpfloat(_mass),
0,
cpCircleShapeGetRadius(shape),
cpCircleShapeGetOffset(shape)));
}
void PhysicsDebugDraw::drawShape(PhysicsShape& shape)
{
for (auto it = shape._info->getShapes().begin(); it != shape._info->getShapes().end(); ++it)
{
cpShape *subShape = *it;
switch ((*it)->klass_private->type)
{
case CP_CIRCLE_SHAPE:
{
float radius = PhysicsHelper::cpfloat2float(cpCircleShapeGetRadius(subShape));
Point centre = PhysicsHelper::cpv2point(cpBodyGetPos(cpShapeGetBody(subShape)))
+ PhysicsHelper::cpv2point(cpCircleShapeGetOffset(subShape));
static const int CIRCLE_SEG_NUM = 12;
Point seg[CIRCLE_SEG_NUM] = {};
for (int i = 0; i < CIRCLE_SEG_NUM; ++i)
{
float angle = (float)i * M_PI / (float)CIRCLE_SEG_NUM * 2.0f;
Point d(radius * cosf(angle), radius * sinf(angle));
seg[i] = centre + d;
}
_drawNode->drawPolygon(seg, CIRCLE_SEG_NUM, Color4F(1.0f, 0.0f, 0.0f, 0.3f), 1, Color4F(1, 0, 0, 1));
break;
}
case CP_SEGMENT_SHAPE:
{
cpSegmentShape *seg = (cpSegmentShape *)subShape;
_drawNode->drawSegment(PhysicsHelper::cpv2point(seg->ta),
PhysicsHelper::cpv2point(seg->tb),
PhysicsHelper::cpfloat2float(seg->r==0 ? 1 : seg->r), Color4F(1, 0, 0, 1));
break;
}
case CP_POLY_SHAPE:
{
cpPolyShape* poly = (cpPolyShape*)subShape;
int num = poly->numVerts;
Point* seg = new Point[num];
PhysicsHelper::cpvs2points(poly->tVerts, seg, num);
_drawNode->drawPolygon(seg, num, Color4F(1.0f, 0.0f, 0.0f, 0.3f), 1.0f, Color4F(1.0f, 0.0f, 0.0f, 1.0f));
delete[] seg;
break;
}
default:
break;
}
}
}
void PhysicsShapeCircle::updateScale()
{
cpFloat factor = std::abs(_newScaleX / _scaleX);
cpShape* shape = _cpShapes.front();
cpVect v = cpCircleShapeGetOffset(shape);
v = cpvmult(v, factor);
cpCircleShapeSetOffset(shape, v);
cpCircleShapeSetRadius(shape, cpCircleShapeGetRadius(shape) * factor);
PhysicsShape::updateScale();
}
void PhysicsShapeCircle::updateScale()
{
cpFloat factor = std::abs(PhysicsHelper::float2cpfloat(_newScaleX / _scaleX));
cpShape* shape = _cpShapes.front();
cpVect v = cpCircleShapeGetOffset(shape);
v = cpvmult(v, PhysicsHelper::float2cpfloat(factor));
((cpCircleShape*)shape)->c = v;
cpCircleShapeSetRadius(shape, cpCircleShapeGetRadius(shape) * factor);
PhysicsShape::updateScale();
}
/* calculate moment for a single shape */
static Scalar _moment(cpBody *body, ShapeInfo *shapeInfo)
{
Scalar mass = cpBodyGetMass(body);
switch (shapeInfo->type)
{
case PS_CIRCLE:
return cpMomentForCircle(mass, 0,
cpCircleShapeGetRadius(shapeInfo->shape),
cpCircleShapeGetOffset(shapeInfo->shape));
case PS_POLYGON:
return cpMomentForPoly(mass,
cpPolyShapeGetNumVerts(shapeInfo->shape),
((cpPolyShape *) shapeInfo->shape)->verts,
cpvzero);
}
}
void
draw_background(SDL_Surface* screen)
{
struct draw_options opts = {
.surface = screen,
.colour = colour(0, 0, 0)
};
sdldraw_rect(opts, 0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
}
static void
draw_circle_shape(struct draw_options opts, cpShape* shape, cpBody* body)
{
cpVect centre = cpvadd(cpBodyGetPos(body),
cpCircleShapeGetOffset(shape));
cpFloat radius = cpCircleShapeGetRadius(shape);
cpFloat angle = cpBodyGetAngle(body);
cpVect edgePoint = cpvadd(centre,
cpv(radius * cos(angle), radius * sin(angle)));
draw_circle(opts, centre, radius);
draw_line(opts, centre, edgePoint);
}
Vec2 PhysicsShapeCircle::getOffset()
{
return PhysicsHelper::cpv2point(cpCircleShapeGetOffset(_cpShapes.front()));
}
Point PhysicsShapeCircle::getOffset()
{
return PhysicsHelper::cpv2point(cpCircleShapeGetOffset(_info->getShapes().front()));
}
