Hi,

for selecting the visible entities in my program I do a hidden drawing with false colors, where each color corresponds to an entity ID, then I read the pixels back and reconstrut the entity ID...

Hi,

Thank you

Hi,

thanks for the answer.
So it's better to compute it by ourselves, right?

Hi,

it seems the gl_LightSource[i].halfVector data is wrong on the Intel HD 3000 graphics card with the latest driver (9.17.10.2875), running OpenGL 3.1 and GLSL 1.40.

I tried computing it by...

I do not create the DC explicitly, I get it from the control:


wnd = control.Handle;
hdc = Windows.GetDC(wnd);
...
hrc = wglCreateContext(hdc);


Then...

Hi, I tried deleting my OpenGL control (which causes the destruction of the graphics context) in the OnClosing() method of the child form, as suggested by that page, but the problem is still there :(

Does anybody have an idea of the reason or how to fix it?

I have a C++/CLI WinForm MDI application, with a main MDI WinForm container that opens some child Forms that contain my OpenGL .Net control.

On some NVidia cards (Quadro 600, Quadro 1000M, Geforce...

Using the core functions the crash happens the same.

Ok,

so I guess we solved the mistery of the back-light illumination.
Thanks.

Hi,

I tried the following (C#) code, that basically allocates an FBO with a 4096x4096 depth texture at each iteration.

On an ATI Radeon 5450 with Catalyst 12.6, under WinXP 32bit, I get an...

But the fixed function is not setting the ambient terms to zero (as my pictures without the shader showed)...

I found out the following things studying my Shader and playing with it in RenderMonkey:

1. The illumination on the backface is given by the ambient component of the spotlight:



ambient ...

Yes,

the normal is pointing towards the upper (front) side of the Quad.

Hi,

for control I mean a Windows Form control with an OpenGL viewport.

Each control has its own opengl graphics context and I don't use the wglShareLists.

Hi Dark Photon,

In the shader I'm doing this:



void ComputeSpotPointParameters( in int i,
in vec3 eye,
in vec3 ecPosition3,
...

I did a test application that opens a form with 12 instances of my OpenGL control,.
Each one creates its FBO of 4096x4096 with associated depth texture for shadowmapping.
On the ATI Radeon 5450,...

Hi,

I showed both cases, with Shader and No Shader (fixed fucntion OpenGL) to show that both cases gives the same result: a little lighting on the backface.

In the case with the Shader the...

I see that even with ConstantAttenuation = 1, in the back face there is a little illumination of the spot (but very very dim), so if constantAttenuation < 1, it would go to increase that dim...

So is it wrong to assign the ConstantAttenuation a value between 0 and 1?

That would make the attenuation factor > 1...

This is the illumination from the top

807


and this is the illumination from the bottom:


808

Ok,

but I set it to false just to be sure...
It seems that if I don't set the attenuation factor it works fine...

Hi,

I have a SpotLight with angle 40 degrees, SpotExponent 10 and ConstantAttenuation 0.01.

My scene consists of a simple Quad.

I see that not onlt the Front Face of the quad is illuminated,...

Anybody could help please?

Hi,
I created a sample that reproduces the problem:
It creates a multisample openGL window and draws some lines (you can move/zoom/rotate with the mouse)

Pressing the 'C' key I call the
...