If you are not setting up your uniforms correctly, you could be accessing the wrong texture. I have seen this happen many times. Make sure the sampler names in your setUniformParameter calls are spelled exactly like the samplers in your shaders. -- Terry Welsh - mogumbo 'at' gmail.com www.reallyslick.com | www.infiscape.com | www.vrsource.org
On 8/19/05, Oliver Kutter <[EMAIL PROTECTED]> wrote: > OK, what else can it be? > > I tried the new nvidia drivers and another graphics card. Both gave the > same unchanged results. > I'm using multitextures. Can it be, that I'm accessing another textures, > and not that one, I want to access? > But I'm not changing anything in my application, I only change the data > of the image. > But the failure is still there! > > And by the ways, I'm searching for another solution. How can I use 64bit > floating point textures. I want to create them, access them in the > shader and render the result to a render target. I know, that I cannot > use the framebuffer, but what can I use instead? I wonder, if I can use > the OpenSG Image Objects for creating 64bit textures? > > bye > Oliver > > Dirk Reiners schrieb: > > > Hi Oliver, > > > >On Thu, 2005-08-18 at 19:27 +0200, Oliver Kutter wrote: > > > > > >>Hello World ;-) , > >> > >>I have a problem with accessing textures in my fragment shader program. > >>I want to access the texture, but not at the fragment's current > >>position. Normally, the program looks up the texture at the specified > >>fragment texture coordinates stored in gl_TexCoords[0]. But I want to > >>get texture values from other coordinates. > >> > >>Example: > >> > >>Normal you do: > >> > >>vec4 myFragColor = texture2D (myTexture, vec2 (gl_TexCoords[0])); > >>gl_FragColor = myFragColor; > >> > >>But I want to do: > >> > >>float texSize = 256.0; > >>float x = xpos / texSize; > >>float y = ypos / texSize; > >>vec4 myFragColor = texture2D (myTexture, vec2 (x, y)); > >>gl_FragColor = myFragColor; > >> > >>Now my Problem: > >>When I choose xpos and ypos as fixed values (e.g. xpos = 50.0, ypos = > >>100.0), I have no problem. I get exactly the color at the specified > >>coordinates (50,100) in the texture. > >>But when I choose xpos and ypos to be variable (what I want to achieve), > >>I get everytime, when I start my application, different color values. > >>The funny thing is, that I have everytime the same (correct) texture > >>coordinates. Sometimes I get the correct color values, but mostly I get > >>the wrong values. > >>I tested it with the following code (I can take x and y as color values): > >> > >>gl_FragColor = vec4 (myFragColor.x, x, y, 1.0); > >> > >> > >> > >>Has anyone an idea? > >> > >> > > > >That sounds reasonable and simple. Have you tried running it on a > >different graphics card/driver combo? GLSL is still not as stable as it > >should be, even though your example is simple enough that I wouldn't > >expect it to be a problem. > > > >Yours > > > > Dirk > > > > > > > > > >------------------------------------------------------- > >SF.Net email is Sponsored by the Better Software Conference & EXPO > >September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices > >Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA > >Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf > >_______________________________________________ > >Opensg-users mailing list > >[email protected] > >https://lists.sourceforge.net/lists/listinfo/opensg-users > > > > > > > ------------------------------------------------------- > SF.Net email is Sponsored by the Better Software Conference & EXPO > September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices > Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA > Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf > _______________________________________________ > Opensg-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/opensg-users > ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ Opensg-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/opensg-users
