I created a simple triangle in a blender with three vertices.
The picture shows the coordinates in the blender.
I export the model with default settings, including "+Y up"
However, here are the vertexes that the .bin file contains.
vertexes:
-1 0 2
1 0 1.5
0 0 -3
indeces
0 1 2
As can be seen, the Z-axis values have changed sign.
Why so?
My guess:
Blender as far as I understand uses left-side coordinate system, and gltf uses right-side coordinate system, maybe that's why it changes the Z-axis.
But, the gltf specification says: "glTF defines +Y as up, +Z as forward, and -X as right;" why then does the X axis not change? After all, in blender +X is right.