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我正在尝试渲染到纹理并随后使用纹理，但由于某种原因它不起作用。

如 Apple文档中所述，

首先，我分配 fbo 以渲染到纹理..

glGenFramebuffers(1, &read_framebuffer);
glBindFramebuffer(GL_FRAMEBUFFER, read_framebuffer);

然后我创建纹理并将其附加到该 fbo ..

glActiveTexture(GL_TEXTURE0);
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE );
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8_OES, 64, 64, 0, GL_RGBA,
             GL_UNSIGNED_BYTE, NULL);
glBindRenderbuffer(GL_RENDERBUFFER, 0);
glBindTexture(GL_TEXTURE_2D, 0);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
                       texture, 0);

然后创建用于绘图的fbo..

glGenFramebuffers(1, &draw_framebuffer);
glBindFramebuffer(GL_FRAMEBUFFER, draw_framebuffer);
glGenRenderbuffers(1, &_colorRenderBuffer);
glBindRenderbuffer(GL_RENDERBUFFER, _colorRenderBuffer);
[_context renderbufferStorage:GL_RENDERBUFFER fromDrawable:_eaglLayer];
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, _colorRenderBuffer);

稍后在渲染循环部分..

glBindFramebuffer(GL_FRAMEBUFFER, read_framebuffer);

(...off-screen drawing the scene here...)

glBindFramebuffer(GL_FRAMEBUFFER, draw_framebuffer);

绑定应该包含我的屏幕外渲染图像的纹理..

glBindTexture(GL_TEXTURE_2D, texture);

(..draw the scene with texture applied here...)

但是，由于某种原因，纹理总是黑色的。我在这里缺少什么吗？

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1 回答 1

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在glTexImage2D交换. GL_RGBA8_OES_ GL_RGBA我可以看到您从苹果文档中获取了这些参数..（没有评论..）无论如何，正如@prideout 指出的那样，关于您的问题的评论，您应该始终检查帧缓冲区状态。在你的情况下，它返回了GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT。

于 2013-03-15T09:22:00.807 回答