glPopAttrib & GL_INVALID_OPERATION

Question

I'm working on some graphical application and i got an GL_INVALID_OPERATION after glPopAttrib(). Predicting the answer "It seems you call glPopAttrib() within glBegin/glEnd block" please see this log i've made with GLIntercept. /* tons of wglGetProcAddress* */ wglGetProcAddress("glEndOcclusionQueryNV")=087C9B10 wglGetProcAddress("glBeginTransformFeedbackN...")=087C9ED0 wglGetProcAddress("glEndTransformFeedbackNV")=087C9F00 glPushAttrib(GL_VIEWPORT_BIT) glPushAttrib(GL_COLOR_BUFFER_BIT) glPushAttrib(GL_COLOR_BUFFER_BIT) glPopAttrib() glPopAttrib() glGetError() = GL_INVALID_OPERATION # <---- THIS glPopAttrib() glPushAttrib(GL_VIEWPORT_BIT) glPushAttrib(GL_COLOR_BUFFER_BIT) glPushAttrib(GL_COLOR_BUFFER_BIT) glPopAttrib() glPushAttrib(GL_POINT_BIT | GL_LINE_BIT | GL_COLOR_BUFFER_BIT) glPopAttrib() glPopAttrib() glPopAttrib() glPushAttrib(GL_VIEWPORT_BIT) glPushAttrib(GL_COLOR_BUFFER_BIT) glPushAttrib(GL_COLOR_BUFFER_BIT) glPopAttrib() glPopAttrib() glPopAttrib() /* and so on */ No glBegin/glEnd callings are made before error-causeing glPopAttrib(). (I used findstr commad to filter the log). The error appears only once, no such (or others) error appers again during the code execution. I have an suspicion that i should call some function before glPushAttrib(GL_VIEWPORT_BIT) or something. JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

I was having the same problem, and finally figured out the cause: When you call a glBindFramebuffer between a glPushAttrib(GL_COLOR_BUFFER_BIT) and a glPopAttrib, a GL_INVALID_OPERATION is caused on the glPopAttrib call. This even happens when you restore the original frame buffer binding before calling glPopAttrib. The only solution seems to be either avoid all glBindFramebuffer calls between the glPushAttrib and glPopAttrib, or avoid using glPushAttrib and glPopAttrib by storing and restoring all relevant color buffer state manually.