将纹理从上下文复制到另一个上下文

Question

我正在尝试复制SDK生成的纹理，它们仅向我提供ID。 我希望将该纹理复制到在Ogre中创建的纹理。

我尝试了以下操作，因为我得到了空白的黑色图像。

Src纹理是mTextureId，目标纹理是tID。

创建上下文：

 mOgreContext = Core::ViewarGeneralMaster::getSingleton()->getViewarMaster()->context();
    self.mEAGLContext = mOgreContext->getContext();

    contextB = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES1
                                     sharegroup:self.mEAGLContext.sharegroup];
    if (!contextB || ![EAGLContext setCurrentContext:contextB]) {
        // Handle errors here
    }


    SixDegreesSDK_Initialize(contextB);
    glGenFramebuffers(1, &fboId);

在主循环中

   if ( mTextureId == 0 )
        {
            mTextureId = SixDegreesSDK_GetBackgroundTexture();
            NSLog( @"Texture id: %d", mTextureId );

        }
        Core::Resolution resolution = Core::EnvironmentInformation::getSingleton()->getScreenResolution();

        glActiveTexture(GLenum(GL_TEXTURE0));

        // 1. Ensure context A is not bound to the texture
        [EAGLContext setCurrentContext:self.mEAGLContext];
        glBindTexture(GL_TEXTURE_2D, 0);


        // 2. Call flush on context A
        glFlush();

        // 3. Modify the texture on context B
        [EAGLContext setCurrentContext:contextB];
        glBindTexture(GL_TEXTURE_2D, mTextureId);
        glBindFramebuffer(GL_FRAMEBUFFER, fboId);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mTextureId, 0);

        //
        // Modify the texture data here
        //

        // 4. Call flush on context B
        glFlush();

        // 5. Rebind the texture on context A
        [EAGLContext setCurrentContext:self.mEAGLContext];
        glBindTexture(GL_TEXTURE_2D, tId);
        glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 0, 0, width, height, 0);

        glFlush();