GetCollisionEngine or .TestOverlapSolid ... is this not part of the official sdk?

I remember using it in my flags behavior but it doesn't seem to be officially supported. (Accessing anything with _ is usually a no-no). I made a suggestion a while ago for it but you know... they take a while if they happen at all.

construct.net/en/make-games/addons/949/flags/versions

Here's the code:

CheckOverlap(flags) {
			const collisionEngine = this._runtime.GetCollisionEngine();
			const flagsInstances = this._behInst._behavior._myInstances._arr;
			let result = false;
			
			result = flagsInstances.some(i => {	
				const t = collisionEngine.TestOverlap(this.GetObjectInstance(), i);
				if(t) {
					if (i.GetBehaviorSdkInstanceFromCtor(C3.Behaviors.Wackytoaster_Flags)._HasFlags(flags)) {
						return true;
					}
				}
			});
			
			return result;
		}

const collisionEngine = this._runtime.GetCollisionEngine();
collisionEngine.TestOverlap(instanceA, instanceB);

In the ghost shooter script, ObjectInstance.TestOverlap(SomeOtherObjectInstance); is used.

There is no _privateVariable marker there, so I would assume its okay, but again.... it isn't "documented", so technically it isn't. I guesse? Idk?

There is a code snippet provided at:

construct.net/en/make-games/manuals/addon-sdk/runtime-reference/event-sheet-classes/eventblock

In the above, _runtime is referenced... Again, no documentation on it, but it is part of an example.

Honestly, without actual, robust, examples, construct's sdk is kind of an exclusive club. The documentation is poor compared to other software. Seems odd to just list a few methods and functions on a webpage and call it good. Reminds me of getting into shaders. The fact that the built in behaviors can't be used as an example... they use so many "cheats", custom runtime modifications, etc...

It means authoring plugins is an obscure and esoteric art fraught with unavoidable pitfalls.

In the ghost shooter script, ObjectInstance.TestOverlap(SomeOtherObjectInstance); is used.

here is no _privateVariable marker there, so I would assume its okay, but again.... it isn't "documented", so technically it isn't. I guesse? Idk?

This is documented actually

construct.net/en/make-games/manuals/construct-3/scripting/scripting-reference/object-interfaces/iworldinstance

But iirc it isn't available in the SDK.

None of these work.

this.testOverlap()
this._inst.testOverlap()
this._inst.GetWorldInfo().testOverlap()

What makes you think that? all the built in behaviors that call it would suffer but they seem performant enough, regardless of how many solids exist.

Hmm maybe you're right, but it was something I had in the back of my head. I even mention it being performance heavy on the addon page.

If you tear open the collision engine you'll see that testOverlapSolid() does:

TestOverlapSolid(inst) {
 const wi = inst.GetWorldInfo();
 this.GetSolidCollisionCandidates(wi.GetLayer(), wi.GetBoundingBox(), tempCandidates);
 for (const s of tempCandidates) {
 if (!this.IsSolidCollisionAllowed(s, inst)) continue;
 if (this.TestOverlap(inst, s)) {
 C3.clearArray(tempCandidates);
 return s;
 }
 }
 C3.clearArray(tempCandidates);
 return null;
 }

GetCollisionCandidates(layer, rtype, bbox, candidates) {
 const isParallaxed = layer ? layer.GetParallaxX() !== 1 || layer.GetParallaxY() !== 1 : false;
 if (rtype.IsFamily())
 for (const memberType of rtype.GetFamilyMembers())
 if (isParallaxed || memberType.IsAnyInstanceParallaxed()) C3.appendArray(candidates, memberType.GetInstances());
 else {
 memberType._UpdateAllCollisionCells();
 memberType._GetCollisionCellGrid().QueryRange(bbox, candidates);
 }
 else if (isParallaxed || rtype.IsAnyInstanceParallaxed()) C3.appendArray(candidates, rtype.GetInstances());
 else {
 rtype._UpdateAllCollisionCells();
 rtype._GetCollisionCellGrid().QueryRange(bbox, candidates);
 }
 }

Wait... this makes me think the javascript part actually is in fact borked because how do you test for overlap? You HAVE to feed individual instances into testOverlap() meaing if you wanna check 1000 spriteA vs 1000 spriteB you have to use

const sprite = runtime.objects.Sprite;
const sprite2 = runtime.objects.Sprite2;

for(const i of sprite.instances()) {
	for(const i2 of sprite2.instances()) {
		if(i.testOverlap(i2)) console.log("coll");
	}
}

Or am I mistaken here? Because like this obviously the evenperformance is better by an insane margin

compared to js

Am I missing something here?

EDIT: Lmao nope, even the ghost shooter example has this issue. The event version has like ~6k collision checks at most where the js version quickly balloons to 20k when shooting. I guess this one is actually worth filing a bug for?

EDIT2: Nevermind I guess github.com/Scirra/Construct-bugs/issues/5665 :V