Select Camera, Render, get image?

Development Programming & Scripting C++
1

Hey All,

I’ve been searching for the answer to this question for nearly a week now and am finally posting it to the forums. I have a level with many cameras. Some are attached to players, some are not. A player might have upwards of 10 cameras. I need to select a specific camera from the level, render its current view and grab the rendered output. That output does not need to be displayed to a screen. I just need to grab it in C++ and send it to another location over the network in one of 2 formats. Either a .jpg or 3 channel 2 dimensional array (RGB channels, height, width).

Thanks!

Another solution might be to select a specific camera and broadcast its view across a network as a live stream. (This may be more optimal.)

2

Have you looked at RenderTargets? They are a material that the camera renders to, then in C++ you can get the color data out of the material. I may have a UE4 snippet of pulling the rgb data from a material still, but it’s on a different workstation, I’ll try to follow up later and add it. I was using a material as a height map, and it worked.

This isn’t exactly what you are looking for, but it is working with color data: https://answers.unrealengine.com/questions/463625/c-updating-texture-data.html

I don’t have code snippet to share, but I did this in UE3 except instead of Rendertarget I took a screenshot from C++ with the camera at the position, orientation, fov etc. that I wanted, then I used DirectX functions in code to manipulate the image further, then sent it in packets over a local network to another UE3 client that saved the packets as .jpegs on it’s local hardrive.

Hope that helps some with direction to look in.

3

I’ve definitely seen the Render Targets. I was hoping to do this completely headless as well. Not sure if it will work without a screen, but will give it a shot. Seems like the only solution is to use RenderTargets. I don’t actually need to render anything at all to a screen ever. Having a screen is just a nice to have thing for this scenario.

So I’ve got a SceneCapture2D component in the scene, and a Render Target. I’ve created a C++ component and I need to get access to the SceneCapture2D’s Render Target. How does one do this? In Unity its self.gameobject.getcomponent<name>();

(I’m an awesome Unity Dev testing out Unreal Engine to see what this thing has to offer.)

4

I’ve come up with an idea to create an actor which has a SceneCapture2D* as a property that can be set, from there I grab the RenderTarget and need to grab the 256x256 pixel data. Does anybody know how to do this? This I think is the peice I need.

5

Got it, I was able to extend the SceneCapture2D class. Any thoughts on how to perhaps dynamically create a new Texture Render Target and set the Render Target in the Scene Capture device programatically?