glUniform1f() not working

[Lazy Foo']

I'm getting some very bizarre behavior here. I'm loading and creating a shader program (that uses the Projection matrix in the vertex shader and sets the fragment's color to magenta in the fragment shader) and glGetError() reports no errors after glUseProgram().

When I call glGetUniformLocation, it returns -1 yet glGetError() returns GL_NO_ERROR.

Yet still the magenta cube shows up.

Here's my shader program creation code along with the code that attempts to set the uniform:

    //Shader Program
    GLuint shaderProgram = 0;
    shaderProgram = glCreateProgram();
 
    //Vertex shader
    GLuint vertexShader = glCreateShader( GL_VERTEX_SHADER );
    GLchar* vertexSource = load_shader( "vertex.glsl" );
    const GLchar** vShaderSource = (const GLchar**)&vertexSource;
    glShaderSource( vertexShader, 1, vShaderSource, NULL );
    glCompileShader( vertexShader );
    glAttachShader( shaderProgram, vertexShader );
    delete[] vertexSource; vertexSource = NULL;
 
    //Fragment shader
    GLuint fragmentShader = glCreateShader( GL_FRAGMENT_SHADER );
    GLchar* fragmentSource = load_shader( "fragment.glsl" );
    const GLchar** fShaderSource = (const GLchar**)&fragmentSource;
    glShaderSource( fragmentShader, 1, fShaderSource, NULL );
    glCompileShader( fragmentShader );
    glAttachShader( shaderProgram, fragmentShader );
    delete[] fragmentSource; fragmentSource = NULL;
 
    //Link and use program
    glLinkProgram( shaderProgram );
    glUseProgram( shaderProgram );
 
    GLenum err = glGetError();
 
    if( err != GL_NO_ERROR )
    {
        quit = true;
    }
 
    GLint uniform = glGetUniformLocation( shaderProgram, "test" );
    std::cout << "Uniform: " << uniform << std::endl;
 
    err = glGetError();
    if( err != GL_NO_ERROR )
    {
        quit = true;
    }
 
    glUniform1f( uniform, 1.f );

Here's vertex.glsl

uniform mat4 LProj;
uniform mat4 LMView;
uniform float test;
 
void main()
{
	gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
 
	//Transforming The Vertex
	//gl_Position = LProj * gl_Vertex;
}

Here's fragment.glsl

uniform float test;
 
void main()
{
	// Setting Each Pixel To Red
	gl_FragColor = vec4(1.0, 0.0, 1.0, 1.0);
}

I'm on an ATI HD 5700. I'm starting to think it's haunted.

[Lazy Foo']

Things just got stranger. This is my log from glslDevil:

W! Program Start
|  wglCreateContext(86011084)
|  wglMakeCurrent(86011084, 00010000)
|  wglGetExtensionsStringARB(86011084)
|  wglChoosePixelFormatARB(86011084, 0028F980, 0028F96C, 1, 0028F964, 0028F968)
|  wglMakeCurrent(00000000, 00000000)
|  wglDeleteContext(00010000)
|  wglCreateContext(02010F6E)
|  wglMakeCurrent(02010F6E, 00020000)
|  glGetString(GL_EXTENSIONS)
|  wglMakeCurrent(02010F6E, 00020000)
|  wglGetCurrentDC()
|  wglGetExtensionsStringARB(02010F6E)
|  glGetString(GL_EXTENSIONS)
|  glGetString(GL_VERSION)
|  glClearColor(1.000000, 1.000000, 1.000000, 1.000000)
|  glClearDepth(1.000000)
|  glMatrixMode(GL_PROJECTION)
|  glLoadIdentity()
|  glMultMatrixd(0028FBD8)
|  glMatrixMode(GL_MODELVIEW)
|  glLoadIdentity()
|  glDisable(GL_BLEND)
|  glEnable(GL_TEXTURE_2D)
|  glEnable(GL_COLOR_MATERIAL)
|  glEnable(GL_DEPTH_TEST)
|  glDepthFunc(GL_LEQUAL)
|  glPolygonMode(GL_FRONT_AND_BACK, GL_LINE)
|  glGetError()
|  glCreateProgram()
|  glCreateShader(GL_VERTEX_SHADER)
|  glShaderSource(2, 1, 0028FD04, 00000000)
|  glCompileShader(2)
|  glAttachShader(1, 2)
|  glCreateShader(GL_FRAGMENT_SHADER)
|  glShaderSource(3, 1, 0028FCF8, 00000000)
|  glCompileShader(3)
|  glAttachShader(1, 3)
|  glLinkProgram(1)
|  glUseProgram(1)
W! OpenGL error GL_INVALID_OPERATION detected
|  glGetError()
|  glGetUniformLocation(1, 004750AA)
W! OpenGL error GL_INVALID_OPERATION detected
|  glGetError()
|  glUniform1f(-1, 1.000000)
W! OpenGL error GL_INVALID_OPERATION detected
|  glClear(GL_DEPTH_BUFFER_BIT|GL_COLOR_BUFFER_BIT)
|  glLoadIdentity()
|  glTranslatef(0.000000, 0.000000, -20.000000)
|  glRotatef(45.000000, 1.000000, 1.000000, 1.000000)
|  glScalef(3.000000, 3.000000, 3.000000)
|  glBegin(GL_QUADS)
|  glColor3f(0.000000, 1.000000, 0.000000)
|  glVertex3f(1.000000, 1.000000, -1.000000)
|  glVertex3f(-1.000000, 1.000000, -1.000000)
|  glVertex3f(-1.000000, 1.000000, 1.000000)
|  glVertex3f(1.000000, 1.000000, 1.000000)
|  glColor3f(1.000000, 0.500000, 0.000000)
|  glVertex3f(1.000000, -1.000000, 1.000000)
|  glVertex3f(-1.000000, -1.000000, 1.000000)
|  glVertex3f(-1.000000, -1.000000, -1.000000)
|  glVertex3f(1.000000, -1.000000, -1.000000)
|  glColor3f(1.000000, 0.000000, 0.000000)
|  glVertex3f(1.000000, 1.000000, 1.000000)
|  glVertex3f(-1.000000, 1.000000, 1.000000)
|  glVertex3f(-1.000000, -1.000000, 1.000000)
|  glVertex3f(1.000000, -1.000000, 1.000000)
|  glColor3f(0.000000, 0.000000, 0.000000)
|  glVertex3f(1.000000, -1.000000, -1.000000)
|  glVertex3f(-1.000000, -1.000000, -1.000000)
|  glVertex3f(-1.000000, 1.000000, -1.000000)
|  glVertex3f(1.000000, 1.000000, -1.000000)
|  glColor3f(0.000000, 0.000000, 1.000000)
|  glVertex3f(-1.000000, 1.000000, 1.000000)
|  glVertex3f(-1.000000, 1.000000, -1.000000)
|  glVertex3f(-1.000000, -1.000000, -1.000000)
|  glVertex3f(-1.000000, -1.000000, 1.000000)
|  glColor3f(1.000000, 0.000000, 1.000000)
|  glVertex3f(1.000000, 1.000000, -1.000000)
|  glVertex3f(1.000000, 1.000000, 1.000000)
|  glVertex3f(1.000000, -1.000000, 1.000000)
|  glVertex3f(1.000000, -1.000000, -1.000000)
|  glEnd()
|  SwapBuffers(02010F6E)
|  wglMakeCurrent(00000000, 00000000)
|  wglDeleteContext(00020000)
E! Child process exited
W! Program termination forced!

Apparently glUseProgram() is giving GL_INVALID_OPERATION, yet glGetError() reported no such problem.

[frank li]

Certainly you will get the location as -1 since "test" is an inactive uniform. But I feel strange that glGetError() returns nothing but glslDevil returns GL_INVALID_OPERATION. I believe glGetError() could throw out the correct error code.

[Lazy Foo']

Certainly you will get the location as -1 since "test" is an inactive uniform.

Well that's something simple I wish I didn't have to learn the hard way.