I've been looking into this for a few hours, to no avail. Basically I have
struct rectangle {
int x, y, w, h;
};
rectangle player::RegionCoordinates() // Region Coord
{
rectangle temp;
temp.x = colRegion.x + coordinates.x;
temp.w = colRegion.w;
temp.y = colRegion.y + coordinates.y;
temp.h = colRegion.h;
return temp;
}
// Collision detect function
bool IsCollision (rectangle * r1, rectangle * r2)
{
if (r1->x < r2->x + r2->w &&
r1->x + r1->w > r2->x &&
r1->y < r2->y + r2->h &&
r1->y + r1->h > r2->y)
{
return true;
}
return false;
}
//blah blah main while loop
if (IsCollision(&player1.RegionCoordinates(), &stick1.RegionCoordinates())) //ERROR
{
player1.score+=10;
stick1.x = rand() % 600+1;
stick1.y = rand() % 400+1;
play_sample(pickup,128,128,1000,false);
}
Any ideas? I'm sure it's something really obvious but for the life of me I can't figure it out.
RegionCoordinates()
returns an object by value. This means a call to RegionCoordinates()
returns a temporary instance of rectangle
. As the error says, you're trying to take the address of this temporary object, which is not legal in C++.
Why does IsCollision()
take pointers anyway? It would be more natural to take its parameters by const reference:
bool IsCollision (const rectangle &r1, const rectangle &r2) {
if (r1.x < r2.x + r2.w &&
r1.x + r1.w > r2.x &&
r1.y < r2.y + r2.h &&
r1.y + r1.h > r2.y) {
return true;
}
return false;
}
//blah blah main while loop
if (IsCollision(player1.RegionCoordinates(), stick1.RegionCoordinates())) //no error any more
{
player1.score+=10;
stick1.x = rand() % 600+1;
stick1.y = rand() % 400+1;
play_sample(pickup,128,128,1000,false);
}