SFML collision detection about tmxlite HOT 4 CLOSED

Hi Fallahn, NathanHoekstra is my collegue. It turned out we designed our map faulty. We designed the map with tiles only, while your library only can intersect with objects, which makes sence. Thanks alot for your help!

from tmxlite.

tmxlite differs from sfml-tmxloader in that it only parses the data stored in a tmx map file into a set of C++ objects. It doesn't support rendering with sfml directly like sfml-tmxloader does, although there is an example in the repository of how to render maps loaded by tmxlite with sfml.

To do collision detection I would do something like this:

• Create a 'collision' or 'intersectable' layer in Tiled which is an object group type. Place down objects on this layer which represent the collision zones. You can use different shapes for your objects, but to start simple I recommend just using rectangles to create AABBs
• Load the map with tmxlite and grab the layers vector from the Map object using getLayers(). Find your collision layer, and then get all the objects from that layer (see this example for how to do that).
• Then for each object use getAABB() and convert it to sf::FloatRect and store it somewhere, for an example std::vector<sf::FloatRect> which will become your list of collision objects.

Once you have all your collision data loaded you can use it with a physics library like box2D or start creating your own collision. I've written an sfml tutorial here which also has links to other tutorials at the bottom. HTH!

from tmxlite.

I think the AL lib part is a separate error and should appear on its own line (it's to do with the program aborting). The actual error is the assertion failing - it checks to see if getType() is returning an object type layer, because that's what you're requesting, but it seems the layer you want is not the correct type.

You can do something like this:

for(const auto& layer : layers)
{
    if(layer->getType() == tmx::Layer::Type::Object)
    {
        //this is the layer you want, try getLayerAs() here.
    }
}

or if you want to use some STL magic:

auto result = std::find_if(layers.begin(), layers.end(),[](const tmx::Layer& l){return l->getType() == tmx::Layer::Type::Object;});
if(result != layers.end())
{
    const auto& objectLayer = result->getLayerAs<tmx::ObjectGroup>();
}
else
{
    std::cout << "Object layer not found\n";
}

from tmxlite.

Hi, thanks for the quick response!

Based on your information. I am using the following code. Note i am sure that my 3th Tiled layer is the layer i want to check.
std::vector<sf::FloatRect> bounds;
const auto& layer = map.getLayers()[2]; const auto& objects = layer->getLayerAs<tmx::ObjectGroup>().getObjects();
for (const auto& object : objects) {
tmx::FloatRect rect = object.getAABB();
bounds.push_back(sf::FloatRect(rect.left, rect.top, rect.width, rect.height));
}
But on runtime i get the following assertion error:
Expression: getType() == Type::Object AL lib: (EE) alc_cleanup: 1 device not closed
It gives this error on line 88 in the ObjectGroup.hpp file

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