Rendering differenet Scenes in different FBOs

beginners
#1

Hi there,

I’ve got a simple question and I hope there is a simple answer^^

How I can render 2 Scenes in 2 FBOs separately?

Is this possible?

Greets
:slight_smile:

#2

Hi Jose Man,

This is absolutely possible and fair simple.

you want to have two ofFbo objects which you’ve allocated and then simply within draw you can write:

fboA.begin();
// Render Scene 1
fboA.end();

fboB.begin();
// Render Scene 2
fboB.end();

Then to view them just draw the directly to the screen:

fboA.draw(0, 0);
fboB.draw(fboA.getWidth(), 0);
#3

Okay, thank you. But work this also:

fboA.begin()
sceneA.draw(0,0,0);
fboA.end();

fboB.begin()
sceneB.draw(0,0,0);
fboB.end();

I mean, SceneA has completely different Lightning and shading for example than SceneB.
You know what I mean?
Is this possible?

#4

Hey Jose,

I don’t know what kind of object your scene object is, but in general this should work.

What object is your sceneA?

JB

#5

Hi Bentley,

Let me explain it as an example:
The first scene is a 2D-Game for example. No Light, no shading. Just simple 2d-graphics.
The 2nd scene is complex 3D-Scene with Lights and Camera movement and shading and so on.

I want to use the FBOs from both scenes to render them on a Cube-Surface, for example.
1 Scene on on the one surface and the other Scene on the other surface…

I know… it sounds strange but something like that I want to do…

#6

I think its a not very simple.
Because there must be a separate render context for each scene…

Maybe I have to reset and set all the scene-settings for each scene everytime I want to render the scenes…

Is there a simple and fast way to set all the OpenGL and render settings to default?

#7

Hi Jose,

I’m not sure of there’s a way to set all openGL settings to default but you can use

ofPushMatrix();
ofPushStyle();
// Render
ofPopStyle();
ofPopMatrix();

to push and pop many openframeworks settings.

JB

1 Like
#8

Hi Bentley,

ah, okay. Cool. I’ll take a look :slight_smile: