>
>
>  4 Separate Laptops, all running Ubuntu 11.04.
>
> One with an ATI Card, running GLX 1.4, OpenGl 3.3, GLSL 3.3, runs as
> expected.
>
> One with an Nvidia Card, running GLX 1.4, OpenGL 3.3, GLSL 3.3, shows no
> effects of the shader.
>
> Another with an Nvidia Card, running GLX 1.4, OpenGL 4.1, GLSL 4.1 runs as
> expected, HOWEVER there is an identical laptop that displays the same
> symptoms as the above laptop with no effects.

>
> There are a couple of strange things happening that I believe may be signs
> of what is is that is causing the lack of shading.
>
> First, if the fragment shader is changed to just color all pixels red
> without reason, the working machines will display a red sphere. The machines
> that don't work, flash the red sphere for one draw, and then the map reverts
> back to the original images(the whole globe can be seen, and the oceans are
> dark).
>
> Second, if a change is made to the java package such that the rendering loop
> doesn't call glUseProgram(0), the working machines render strangely, but
> still close, and the machines that are not working will have a translucent
> sphere that is whatever color I set GL_fragcolor to in the shader. This is
> made even more strange by the fact that it is ignoring the discared pixels
> and shading them this color anyways.
>
> Third, most of the debugging information I've gotten from turning jogl
> debugging on is trash, but on the ATI machine I can see it retrieving a
> power-of-two texture quite often, while on the nvidia machine that doesn't
> have an identical pair, the power-of-two texture comes up once or twice at
> the beginning of runtime.
>
> The shaders are receiving a uniform sampler2D from the JOGL code, and using
> it to create a texture2D that the color of the pixel is retrieved
> through.<br></br><br></br>Fragment Shader
> <br></br>
>
>     uniform sampler2D tile_image;
>     uniform float brightness;
>     const vec3 coef = vec3(0.2125, 0.7154, 0.0721);
>     uniform float saturation;
>     uniform vec4 hueToAdjust;
>  
>     vec4 shadeTile(vec4 tile_val);
>
>     //Fragment shader. Colors every coordinate that is mostly blue to a
> lighter blue.
>     void main (void)
>     {
>    
>        if (gl_TexCoord[0].s < 0 || gl_TexCoord[0].s > 1) discard;
>        if (gl_TexCoord[0].t < 0 || gl_TexCoord[0].t > 1) discard;
>        vec4 tile_val = texture2D(tile_image, gl_TexCoord[0].st);
>  
>        //this if statement catches the majority of the ocean areas
>        if(tile_val.b >= (tile_val.g+tile_val.r))
>        {
>             tile_val = shadeTile(tile_val);
>        {
>        gl_FragColor = vec4 (tile_val.rgba);
>     }
>
>     vec4 shadeTile(vec4 tile_val)
>     {
> //saturation
>     vec4 intensity = vec4(dot(tile_val.rgb,coef));  
>     tile_val = mix(intensity, tile_val, saturation);
>  
>   //contrast
>   tile_val = brightness * (1.0 - saturation) + tile_val;
>  
> //hue adjust
>   tile_val.rgba *= hueToAdjust;
>  
>   //brightness
>   tile_val.rgba *= brightness;
>  
>
>     return tile_val;
> }
>
> Vertex Shader:
>
>     void main(void)
>     {
>    
>         gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0;
>         gl_TexCoord[1] = gl_TextureMatrix[0] * gl_MultiTexCoord1;
>         gl_Position = ftransform();
>     }
>
> Render Loop:
>
>     Public void render(DrawContext dc)
>     {
>         if (d_doRender)
>         {
>             GL gl = dc.getGL();
>             if (d_glsl != null && d_glsl.isShaderSupported())
>             {
>                 d_glsl.useShaders();
>                 d_glsl.startShader();
>                 gl.glUniform1i(d_glsl.getUniformLocation("tile_image"), 0);
>                 gl.glUniform1f(d_glsl.getUniformLocation("saturation"),
>                                d_saturation);
>                 gl.glUniform4f(d_glsl.getUniformLocation("hueToAdjust"),
>                                d_hueToAdjust[0], d_hueToAdjust[1],
>                                d_hueToAdjust[2], d_hueToAdjust[3]);
>                 gl.glUniform1f(d_glsl.getUniformLocation("brightness"),
>                                d_brightness);
>             }
>             super.render(dc);
>             if (d_glsl != null && d_glsl.isShaderSupported())
>             {
>                     d_glsl.endShader();
>             }
>         }
>     }
>
>
> It is also of note that the program and shader infologs give no information
> on the machines that are not working, while on the ATI machine they say that
> the shaders were successfully compiled to run on this hardware.