Hi everyone, today I realized something about draw calls. I have done some basic tests and results surprised me.
1- Firstly I put a sky with 1 mesh and 1 material so I had 2 draw calls. As expected.
2- And I put a cube static mesh from basics tab and draw call increased to 4 from 2. As expected. (1 for mesh and 1 for material)
3-Then I put a movable skylight. No any change. As expected.
4-When I put a movable directional light (with 1 cascade). Draw call increased to 6 from 4. This was surprised me because I did not expect that a shadow (from static mesh) brings 2 draw calls.
This is my first question. Is this usual? Is anyone here to inform us about that?
5-So I dug a bit more and I put another static mesh which has 2 materials. And it brings 4 draw calls without shadow. If I turn on shadows it brings 8 draw calls (4 calls for shadow.) Isn’t something wrong here?
6- And my last experiment was about skeletal meshes. I put a skeletal mesh which has 1 mesh and 1 materials. It brings 3 draw calls. (this was 2 calls on same static mesh) and when I turn on shadows it brings 5 calls (2 for shadow). Finally, I put another skeletal mesh which has 1 mesh and 2 materials. And it brings 6 draw calls without shadow. And 10 draw calls with shadow.
These situations were pretty weird to me and I wanted to share here. I hope there is someone here to keep us informed.