addMeshAt in MeshBatch

MacShrike

Ls,

Does this insert a new set of vertices and indices or overwrite at the parameter Index position?
I had a look at the code but I'm not sure I understand completely.

If I would like to store the index position of an inserted mesh should I calculate that like:
from the count it got inserted * ( 6 (number of indices per quad?) + extra values added in the meshstyle)
?

To be specific I want to know the index position of a(any actually) mesh that I store in the Meshbatch.
How can I do that best?

Regards,
Mac

JohnBlackburne

It copies the data, to the position specified. It is up to the developer to make sure that doing so makes sense. The obvious use case is when you have a Mesh which was added already to the MeshBatch, and you want to update it.

Note doing so will mean it has to upload all its data again, as it only knows how to upload it in one go, it does not keep track of the separate Meshes, can’t upload just the Mesh data you have changed. If you are doing a lot of updating parts of a MeshBatch, it might be more efficient to keep them as separate Meshes, and let Starling cache them.

MacShrike

Dear John,

That is good news.

Perhaps you could help me further,
Since the adding a mesh does not return its index position in the batch as a parameter I will have to calculate it.
Assuming I use only the exact same meshes to overwrite it should work.
Since I already have it reupload everything because I .clear() the meshbatches now and refill them, doing a clever overwrite of only the "dirty" meshes should save me tons op cpu time.

So to calculate: How many indices does an image mesh have? I'm assuming the requested Index in addMeshAt is the bytecount in the bytearray?
and
I put a style on each that has 2 extra float4 variables for use in the style, since this data gets added in the vertices does that affect my bytecount for the index position/size of the bytearray?

Perhaps I could tweak the addMesh.as so that it returns the index position on which it was starting with.

Regards,
Mac

JohnBlackburne

An Image is just a Quad with a Texture, so has the same number of vertices and indices, 4 and 6.

You could tweak addMesh. Or you could get the vertexData.numVertices and indexData.numIndices of of the MeshBatch before you add a new Mesh, as that is where any new Mesh is added.

MacShrike

JohnBlackburne

Thanks,

I was confused because the addmeshAt parameter is called index.
And the number of indexes and vertices is not the same so I thought I perhaps had to add them together ort something

MacShrike

Nm, I confused myself with the index as beeing an index not as beeing the indices.
You pass the indicesIndex and the vertex index.
That makes sense to me know.

Thank you very much