It is possible by setting a layer to clear depth before you render meshes in a layer that you want to render on top of everything else.
I’ve done it in the project here: https://playcanvas.com/project/950571/overview/fps-pit
I’ve made a layer called ‘Clear Depth’ that I set in code to clear the depth buffer.
Code: https://playcanvas.com/editor/code/950571?tabs=95528900
(function() {
const app = pc.Application.getApplication();
app.on('start', () => {
// We have special layer that we want to set so that it clears the depth buffer
// This helps us render the weapon on top of the world
const clearDepthLayer = app.scene.layers.getLayerByName('Clear Depth');
clearDepthLayer.clearDepthBuffer = true;
});
})();
This means that anything that renders after this layer is going to render over anything that has rendered before.
In my case, the Weapon layer that the gun is on:
