Has anyone been able to run fragment shaders (Cg)?

OpenGL Development JOGL Development
#1

Vertex programs works just fine, but when I try to bind a fragment program, the jvm crashes.

I load the following fragment program:

void mainf (
                  float4 iColor : COLOR,
            out float4 oColor : COLOR            )
{
      oColor = iColor;
}

IE just a passthrough.
CgGL loads the program just fine and compiles it.

CgGL.cgGetProgramString(fragmentProgram, CgGL.CG_COMPILED_PROGRAM) shows the following:

// nvparse 1.0 output generated by NVIDIA Cg compiler
// cgc version 1.2.1001, build date Mar 17 2004  10:32:28
// command line args: -q -profile fp20 -entry mainf
//vendor NVIDIA Corporation
//version 1.0.02
//profile fp20
//program mainf
//var float4 iColor : $vin.COLOR : COLOR0 : 0 : 1
//var float4 oColor : $vout.COLOR : COLOR : 1 : 1
!!RC1.0
out.rgb = unsigned(col0.rgb);
out.a = unsigned(col0.a);
// 0 instructions
// End of program

Seems fine to me.

The rendering:

System.out.println("1");            
CgGL.cgGLEnableProfile(fragmentProfile);
System.out.println("2");            
CgGL.cgGLBindProgram(fragmentProgram);
System.out.println("3");            

renderModel(gl, glu);
        
CgGL.cgGLDisableProfile(fragmentProfile);

The output:

1
2
An unrecoverable stack overflow has occurred.

An unexpected exception has been detected in native code outside the VM.
Unexpected Signal : EXCEPTION_STACK_OVERFLOW (0xc00000fd) occurred at PC=0x2E74587
Function=[Unknown.]
Library=C:\Program Files\NVIDIA Corporation\Cg\bin\cgGL.dll

NOTE: We are unable to locate the function name symbol for the error
      just occurred. Please refer to release documentation for possible
      reason and solutions.


Current Java thread:
        at net.java.games.cg.CgGL.cgGLBindProgram0(Native Method)
        at net.java.games.cg.CgGL.cgGLBindProgram(CgGL.java:894)
        at CgTest.display(CgTest.java:77)
        at net.java.games.jogl.impl.GLDrawableHelper.display(GLDrawableHelper.java:74)
        at net.java.games.jogl.GLCanvas$DisplayAction.run(GLCanvas.java:221)
        at net.java.games.jogl.impl.GLContext.invokeGL(GLContext.java:290)
        - locked <0x100901b8> (a net.java.games.jogl.impl.windows.WindowsOnscreenGLContext)
        at net.java.games.jogl.GLCanvas.displayImpl(GLCanvas.java:208)
        at net.java.games.jogl.GLCanvas.display(GLCanvas.java:75)
        at net.java.games.jogl.Animator$1.run(Animator.java:107)
        at java.lang.Thread.run(Thread.java:534)

Vertex programs work just fine, and the Cg effects browser thingie works without crashing.

Has anyone gotten this to work?

#2

Would be useful to know what hardware you’re using, and what compile target you’re using. Some hardware, particularly GF2-class hardware, can’t support fragment shaders.

#3

That’s not it. I’ve run the exact same fragment shader via the Cg effect browser thingie.

The target is fp20 (ie NV_texture_shader + NV_register_combiners), the call to CgGL.cgGLIsProfileSupported() returns true, the program compiles and loads just fine, and I’ve got a GF Ti4800. The only problem is a jvm crash when I bind it.

I can bind vertex programs just fine.

#4

Even if you don’t know the solution to my problem, I’d really appreciate it if anyone who has managed to get fragment programs to work from jogl would say so. =)

#5

We have them working fine, but not done any work with Cg. Whether or not a shader works is entirely dependent on the hardware and compile targets.

#6

Er, ok. So what did you use? HLSL?

#7

Everything but Cg… HLSL, GLSL and GL vp/fp. All work fine, including some rather complex work involving shaders being used on pbuffers before applying to the final surface.

#8

Ah, 'fcourse.

starts pondering alternatives

#9

Hi
I have seen cg fragmentshaders running in jogl, and as far as I can understand, once CG an GLSL and the like are compiled there should be no difference? (please correct me if i’m wrong)

// Gregof

#10

That’s sort of correct. Cg currently compiles down to the OpenGL Vertex/Fragment Program capabilities which are part of the core API for GL 1.4. Even the new Cg 1.3 beta spec does not have a GLSL compile target yet. The profile may say it supports it, but you really have to check the hardware and drivers to know whether it really does.