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Is GlVertexAttribPointer required every time glBindBuffer is called?

In OpenGL (specifically OpenGL ES 2.0), should glVertexAttribPointer be called every time a new VBO is bound?

For instance:

glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer1);

glVertexAttribPointer(ATTRIB_POSITION, 2, GL_FLOAT, GL_FALSE, sizeof(vertexStruct), (void*)offsetof(vertexStruct,position));
glEnableVertexAttribArray(ATTRIB_POSITION);
glVertexAttribPointer(ATTRIB_COLOR, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(vertexStruct), (void*)offsetof(vertexStruct,color);
glEnableVertexAttribArray(ATTRIB_COLOR);

glDrawElements(GL_TRIANGLE_STRIP, sizeof(indices)/sizeof(GLubyte), GL_UNSIGNED_BYTE, (void*)0);

// If vertexBuffer2 has the exact same attributes as vertexBuffer1
// is this legal or do the calls to glVertexAttribPointer (and glEnableVertexAttribArray)
// required again?

glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer2);
glDrawElements(GL_TRIANGLE_STRIP, sizeof(indices)/sizeof(GLubyte), GL_UNSIGNED_BYTE, (void*)0);

I know that there are VAOs that do not call glVertexAttribPointer, but I wonder if it is ok to do this in OpenGL?

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1 answer

If you have done this:

glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer1);

glVertexAttribPointer(ATTRIB_POSITION, 2, GL_FLOAT, GL_FALSE, sizeof(vertexStruct), (void*)offsetof(vertexStruct,position));
glEnableVertexAttribArray(ATTRIB_POSITION);
glVertexAttribPointer(ATTRIB_COLOR, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(vertexStruct), (void*)offsetof(vertexStruct,color);
glEnableVertexAttribArray(ATTRIB_COLOR);

glBindBuffer(GL_ARRAY_BUFFER, 0);

glDrawElements(GL_TRIANGLE_STRIP, sizeof(indices)/sizeof(GLubyte), GL_UNSIGNED_BYTE, (void*)0);

. gl*Pointer , , GL_ARRAY_BUFFER , . , , , - gl*Pointer.

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