纹理显示为白色

Question

I have a textured skydome. It renders white when an image is attached, but it does renders right when a color is given. I have reasons to assume the texture is overwritten, thus some tips on this would be great. It used to work fine, displaying the texture appropriately.

EDIT: If I print the texture directly to the fbo, it does show the texture. However when I map it to the sphere it shows up white. Give the sphere a color, and it shows correctly with the color. Also for the record, white is not the clear color. And I use an image that's quite large (3000x1000~).

ADD: No errors are given anywhere.

Changing:

glActiveTextureARB(GL_TEXTURE6_ARB);
glCallList(SkySphere.getDisplayList());

To:

glActiveTextureARB(GL_TEXTURE0_ARB);
glCallList(SkySphere.getDisplayList());

displays the proper image once, first cycle, then, white again.

    glBindTexture(GL_TEXTURE_2D, 0);
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fboId);

    glViewport(0,0,screenWidth,screenHeight);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(90.0f, ((float)screenWidth/(float)screenHeight),0.1f,100.0f);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glShadeModel(GL_SMOOTH);
    glHint(GL_PERSPECTIVE_CORRECTION_HINT,
        GL_NICEST);
    glDisable(GL_DEPTH_TEST);
    glClearColor(1.0f,1.0f,0.0f,1.0f);
    glClear (GL_COLOR_BUFFER_BIT);

    glLoadIdentity (); 

    camera.look();
    glEnable(GL_TEXTURE_2D);
    glDisable(GL_LIGHTING);

    glActiveTextureARB(GL_TEXTURE6_ARB);
    glCallList(SkySphere.getDisplayList());

    glDisable(GL_TEXTURE_2D);

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);

This is the skysphere code:

public static int loadTexture(String filename) {
        ByteBuffer buf = null;
        int tWidth = 0;
        int tHeight = 0;

        .. load png into buffer..

        // Create a new texture object in memory and bind it
        textureId = GL11.glGenTextures();
        GL11.glBindTexture(GL11.GL_TEXTURE_2D, textureId);

        // All RGB bytes are aligned to each other and each component is 1 byte
        GL11.glPixelStorei(GL11.GL_UNPACK_ALIGNMENT, 1);

        // Upload the texture data and generate mip maps (for scaling)
        GL11.glTexImage2D(GL11.GL_TEXTURE_2D, 0, GL11.GL_RGB, tWidth, tHeight, 0, 
                        GL11.GL_RGBA, GL11.GL_UNSIGNED_BYTE, buf);          
        // Setup what to do when the texture has to be scaled
        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER, 
                        GL11.GL_NEAREST);
        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER, 
                        GL11.GL_LINEAR);


        return textureId;
}

public static int getDisplayList() {
    return displayList;
}

public static int makeSphere() {
    Sphere s = new Sphere();       // an LWJGL class for drawing sphere
    s.setOrientation(GLU.GLU_INSIDE);  // normals point inwards
    s.setTextureFlag(true);           // generate texture coords
    displayList = GL11.glGenLists(1);
    GL11.glNewList(displayList, GL11.GL_COMPILE);
    {
        GL11.glPushMatrix();
        {
                    GL11.glBindTexture(GL11.GL_TEXTURE_2D, getTextureId());
            //GL11.glTranslatef(0,0,0);
            GL11.glRotatef(90f, 1,0,0);     // rotate the sphere to align the axis vertically
            s.draw(1, 48, 48);              // run GL commands to draw sphere
        }
        GL11.glPopMatrix();
    }
    GL11.glEndList();
    return displayList;
}

In initGL:

    SkySphere.createShader();
    SkySphere.loadTexture("textures/panorama2.png");
    SkySphere.makeSphere();

Also I'm doing most of my work in framebuffers:

    glBindTexture(GL_TEXTURE_2D, 0);
    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, modelsFboId);

And in one occasion copy the depth to a texture:

    glActiveTextureARB(GL_TEXTURE3_ARB);
    glBindTexture(GL_TEXTURE_2D, modelsDepthTextureId);
    glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 0, 0, screenWidth, screenHeight);
    glBindTexture(GL_TEXTURE_2D, 0);

    glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);    

Answer 1

I used

    glPushAttrib(GL_ALL_ATTRIB_BITS);

at the beginning and

    glPopAttrib();

at the end to reset the OpenGL states each frame.