# OpenGL [CgFX] I ahve a few question about CgFX with OpenGL

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**im using CgFX 1.5 beta 2** So far i can load a CgFX get/set parameters etc, but I soon as I load a new CgFX file it all goes wrong. I get errors like during runtime. - invalid param handle - invalid technique - etc. only the last loaded CgFX is working. it is as if it sets parameters, techniques etc from one CgFX with another. Am I forgetting to do something like: cgSetCurrentEffect(myEffect)? see code below how I load and use a CgFX file, every CgFX file is wrapped in a class:

// construct
m_cgContext = cgCreateContext();
cgGLRegisterStates(m_cgContext);
cgGLSetManageTextureParameters(m_cgContext, CG_TRUE);

m_cgTechnique = cgGetFirstTechnique(m_cgEffect);

while (m_cgTechnique && cgValidateTechnique(m_cgTechnique) == CG_FALSE)
{
// get next technique
m_cgTechnique = cgGetNextTechnique(m_cgTechnique);
}

// CgFXShader is the class that wraps a CgFX file and contains all info about technique, params etc

// Render
while (pass)
{
cgSetPassState(pass);

//DrawGeometry
cgResetPassState(pass);

pass = cgGetNextPass(pass);
}


Next question: Do I need to create a new CGcontext for every CgFX file or do I create 1 CGcontext and use it to for all other CgFX files?

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Try 1.5 final and see if you still get those errors. If so let me know! Also more code would help here.

You can use one context for all CgFX effects. The only thing you can't currently do is mix GL and D3D CgFX effects with one context. Each api needs its own context. This is just FYI.

Also you only need to call cgGLRegisterStates once per context. It shouldn't hurt if you called it more than once, but there's no point.

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1.5 final must have been 2day, I often check the nvidia's developers site and yesterday 1.5 final wasnt on yet. Ill try it 1st and post back if it helped or not.

edit:

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The links seem to work for me...

Oh and 1.5 went live around 8pm Central Time yesterday.

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they must have fixed it, a few minutes ago i they didnt work :P

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I didnt work :(

here's more how I do it:

//Initialisation (once)
m_cgContext = cgCreateContext();cgGLRegisterStates(m_cgContext);cgGLSetManageTextureParameters(m_cgContext, CG_TRUE);

class CgFXShaderpublic:	CgFXShader(const char* file, CGcontext cgContext);	CgFXShader();	~CgFXShader();	CGeffect GetEffect()	{ 		return m_cgEffect; 	}	CGtechnique GetTechnique() 	{ 		return m_cgTechnique; 	}	bool LoadCgFXShader(const char* file, CGcontext cgContext);private:	// effect	CGeffect  m_cgEffect;	CGtechnique m_cgTechnique;};

bool CgFXShader::LoadCgFXShader(const char* file, CGcontext cgContext){	// debug print	Console->AddMessage("Loading CgFXShader: %s", file);	bTextureManagement = cgGLGetManageTextureParameters(cgContext);	m_name.append(file);	// load effect from file	m_cgEffect = cgCreateEffectFromFile(cgContext, file, NULL);	if(!m_cgEffect)	{		OutputDebugString(cgGetLastListing( cgContext ));		return false;	}	CGparameter l_cgParameter = cgGetFirstEffectParameter( m_cgEffect );	while (l_cgParameter)	{		ParseParameter(l_cgParameter);		l_cgParameter = cgGetNextParameter( l_cgParameter );	}	// Get valid techique	m_cgTechnique = cgGetFirstTechnique(m_cgEffect);	while (m_cgTechnique && cgValidateTechnique(m_cgTechnique) == CG_FALSE)	{		Console->AddMessage(cgGetTechniqueName(m_cgTechnique));		Console->AddMessage(cgGetLastListing(cgContext));				// get next technique		m_cgTechnique = cgGetNextTechnique(m_cgTechnique);	}	// debug output current technique name	if (m_cgTechnique)	{		Console->AddMessage("- Current Technique: %s", cgGetTechniqueName(m_cgTechnique));		return true;	}	else	{		Console->AddMessage("- ERROR: No Valid Technique");		return false;	}}

Render:

// for every cgfxfor(unsigned int i = 0; i < nrCgShaders; ++i){    pCgFXShader = m_vShaders;    CGpass pass = cgGetFirstPass(pCgFXShader->GetTechnique());    while (pass)     {	cgSetPassState(pass);        // for every geometry that uses this cgfx        for(unsigned int x=0; x < nrGemoetry; ++x)            DrawGeometry[x].Render();        cgResetPassState(pass);	pass = cgGetNextPass(pass);    }}

this is the complete source. as i said before as soon as I try to load a new cgfx file the previous becomes invalid. I though that I might be doing sometrhing wront with the params and loaded 2 very simple xgfx file with 0 parameters:

// fixed function fog
technique main {    pass 	{        FogEnable = true;        FogMode = linear;        FogDensity = 5.;        FogStart = 128.0f;        FogEnd = 2048.0f;        FogColor = float4(.72f, .72f, .72f, .72f);    }}

// fixed function lighting
technique main {    pass 	{        LightingEnable = true;        LightEnable[0] = true;        LightPosition[0] = float4(-10, 10, 10, 1);        LightAmbient[0] = float4(.1,.1,.1,.1);        LightDiffuse[0] = float4(1,1,1,1);        LightSpecular[0] = float4(1,1,1,1);        MaterialShininess = 10.f;        MaterialAmbient = float4(1,1,1,1);        MaterialDiffuse = float4(.5, .5, .5, 1);        MaterialSpecular = float4(.5, .5, .5, 1);    }}

btw im using ATI hardware (ATI 9700np)

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Ok I'll look into this in more detail.

I hope this isn't an ATI driver issue. We have been wanting to make Cg more friendly to ATI. As a matter of fact, I have an ATI card that is just for ATI-Cg testing.

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this morning i tried the same build on a pc with an nvidia card and got the same results. and from your replies I got the impression that there was nothing wrong with the code I posted and knew it had to do with something else.

after some debugging i suspected the array in which the cgfx are stored in, for this i used std::vector. I changed it to a static array and it worked perfectly.

// this i how i was using it.

// here's the constructor
{
}

I dont really understand why, but i have a feeling that it has to to with how std::vector pushes values and the memory managent. if im correct in my case CgFXShader(file, m_cgContext) is placed on the stack. std::vector copies it and after that the memory is freed again resulting in invalid pointers etc. but. the desconstructor of CgFXShader doesnt do anything (yet)

{
}

thx for your time and efford and sorry for wasteing your time on this. i know you are very bussy with the cg team.

I also wanna take this oppurtunity to ask if you have any word on when FX Composer 2.0 will be released? :D

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Ah good, I'm glad you found the problem. I was just about to go through your code in more detail. :) I didn't have a chance to this weekend.

As far as FXComposer 2.0, I really don't know when it's supposed to be released. That's a question for the tools group and I'm not sure if they are wanting to say anything just yet. I wouldn't think it would be too much longer though.

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