Drawing quad with custom geometry

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#1

Hi I wanted to draw a simple bordered quad (no fill) with custom geometry, but I can’t get it to look right, I got some weird line that goes down to negative infinity I guess:
obraz
My code:
quad = scene->CreateChild();

	CustomGeometry* cg = quad ->CreateComponent<CustomGeometry>();

	cg->Clear();
	cg->SetNumGeometries(1);
	cg->BeginGeometry(0, PrimitiveType::LINE_STRIP);

	cg->DefineGeometry(0, PrimitiveType::LINE_STRIP, 4, false, true, false, false);

	cg->DefineVertex(Vector3(0, 0.1f, 0));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(1, 0.1f, 0));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(1, 0.1f, 1));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(0, 0.1f, 1));
	cg->DefineColor(Color::BLUE);

	Material* mat = new Material(context_);
	auto teq = cache->GetResource<Technique>("Techniques/NoTextureUnlitVCol.xml");
	mat->SetTechnique(0, teq);
	cg->SetMaterial(mat);

	cg->Commit();

I tried changing LINE_STRIP to LINE_LIST, and adding 5. vertex same as first vertex, I got a quad but still there is a line that goes down.

#2

I think you should try use either DefineGeometry or BeginGeometry.

1 Like
#3

Good to know but that still didn’t work.
But I made it work with that:

	cg->DefineVertex(Vector3(0, 0.1f, 0));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(1, 0.1f, 0));
	cg->DefineColor(Color::BLUE);

	cg->DefineVertex(Vector3(1, 0.1f, 0));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(1, 0.1f, 1));
	cg->DefineColor(Color::BLUE);

	cg->DefineVertex(Vector3(1, 0.1f, 1));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(0, 0.1f, 1));
	cg->DefineColor(Color::BLUE);

	cg->DefineVertex(Vector3(0, 0.1f, 1));
	cg->DefineColor(Color::BLUE);
	cg->DefineVertex(Vector3(0, 0.1f, 0));
	cg->DefineColor(Color::BLUE);
#4

I think your original code should work if you removed the cg->DefineGeometry() line and added another blue vertex with position 0, .1, 0 (I’m not certain the last vertex is needed, though).

#5

Thanks, it works, I think I was trying that before but because of using also DefineGeometry() it gave me that line going to bottom.