Performance Issues.

[Josh]

I found the cause and it is very strange. You can simulate this in any C++ program simply by adding this code at the end of the App::Start() function:

    for (int n = 0; n < 36*6; n++)
   {
       Buffer::Create(64, 64, 0, 1);
   }

 

It seems that having an FBO just exist and not do anything degrades performance on Nvidia cards.

[Josh]

...I was right. Even calling the simplest possible pure FBO commands does it:

    for (int n = 0; n < 36*6; n++)
   {
       uint32 framebuffer;
       glGenFramebuffers(1, &framebuffer);
       glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
   }
   glBindFramebuffer(GL_FRAMEBUFFER, 0);

[Josh]

And another example. when TESTFBO=0 FPS is 100, drops in half if you set TESTFBO=1:

#include "App.h"

using namespace Leadwerks;

App::App() : window(NULL), context(NULL), world(NULL), camera(NULL) {}

App::~App() { delete world; delete window; }

bool App::Start()
{
window = Window::Create();
context = Context::Create(window);
world = World::Create();
camera = Camera::Create();
camera->Move(0, 0, -8);

#define TESTFBO 1

#if TESTFBO==1
for (int n = 0; n < 36 * 6; n++)
{
	uint32 framebuffer;
	glGenFramebuffers(1, &framebuffer);
	glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
}
glBindFramebuffer(GL_FRAMEBUFFER, 0);
#endif	

return true;
}

bool App::Loop()
{
if (window->Closed() || window->KeyDown(Key::Escape)) return false;

Time::Update();
world->Update();
world->Render();

context->SetBlendMode(Blend::Alpha);
context->SetColor(1, 1, 1, 1);
context->DrawText(String(Time::UPS()),0,0);

context->Sync(false);

return true;
}

[Josh]

I'm reporting this to Nvidia. In the meantime I recommend using the Static + Dynamic setting for your lights.

https://devtalk.nvidia.com/default/topic/813945/general-graphics-programming/bug-report-non-active-fbo-causes-much-slower-rendering/

[AnthonyPython]

that's certainly odd.

[shadmar]

That is wierd. Maybe it's driver version related.

[YouGroove]

It is not possible to simply drop FBO once for all ?

[Josh]

FBO is how render-to-texture is performed. It's part of the basic functionality of OpenGL.

[gamecreator]

https://www.opengl.org/wiki/Framebuffer_Object

[shadmar]

I'm reporting this to Nvidia. In the meantime I recommend using the Static + Dynamic setting for your lights.

https://devtalk.nvidia.com/default/topic/813945/general-graphics-programming/bug-report-non-active-fbo-causes-much-slower-rendering/

 

I get 1000fps in either using your uploaded test to nvidia.

Win 8.1 - GTX 770M 344.75 drivers. (laptop)

 

Edit:

However fraps says 2270 fps (off.exe) and 2060 fps (on.exe)

[shadmar]

And installed 347.52.. (why did I do that...)

 

off.exe = 2270 fps as before

on.exe = 540 fps ... wow that is insane...

 

Rolling back to 344.75..

[shadmar]

Still broken in 347.88 (released march 17th..)

[shadmar]

350.12 same issue.

 

Can't this be worked around by putting some data in the buffers on your end?

[reepblue]

On my end, If I have a directional light with even Static shadows, my framerate gets cuts in half. (On a good size map with 350.12.)

 

EDIT: It's seems it's something with my exe that handles menuUI and such. Installed the older exes and the game runs fine.