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<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glCheckFramebufferStatus</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glCheckFramebufferStatus"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glCheckFramebufferStatus — return the framebuffer completeness status of a framebuffer object</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">GLenum <strong class="fsfunc">glCheckFramebufferStatus</strong>(</code></td><td>GLenum <var class="pdparam">target</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>target</code></em></span></dt><dd><p>
                    Specifies the target framebuffer object.
                    The symbolic constant must be <code class="constant">GL_FRAMEBUFFER</code>.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            <code class="function">glCheckFramebufferStatus</code> returns a symbolic
            constant that identifies whether or not the currently bound
            framebuffer is framebuffer complete, and if not, which of the rules
            of framebuffer completeness is violated.
        </p><p>
            If the framebuffer is complete, then 
            <code class="constant">GL_FRAMEBUFFER_COMPLETE</code> is returned. 
            If the framebuffer is not complete, the return values are as follows:
        </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="constant">GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT</code></span></dt><dd><p>
                        Not all framebuffer attachment points are framebuffer
                        attachment complete. This means that at least one
                        attachment point with a renderbuffer or texture 
                        attached has its attached object no longer in existence
                        or has an attached image with a width or height of 
                        zero, or the color attachment point has a 
                        non-color-renderable image attached, or the
                        depth attachment point has a non-depth-renderable
                        image attached, or the stencil attachment point has a
                        non-stencil-renderable image attached.
                    </p><p>
                        Color-renderable formats include <code class="constant">GL_RGBA4</code>,
                        <code class="constant">GL_RGB5_A1</code>, and
                        <code class="constant">GL_RGB565</code>.
                        <code class="constant">GL_DEPTH_COMPONENT16</code> is the only
                        depth-renderable format. 
                        <code class="constant">GL_STENCIL_INDEX8</code> is the only
                        stencil-renderable format.
                    </p></dd><dt><span class="term"><code class="constant">GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS</code></span></dt><dd><p>
                        Not all attached images have the same width and height.
                    </p></dd><dt><span class="term"><code class="constant">GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT</code></span></dt><dd><p>
                        No images are attached to the framebuffer.
                    </p></dd><dt><span class="term"><code class="constant">GL_FRAMEBUFFER_UNSUPPORTED</code></span></dt><dd><p>
                        The combination of internal formats of the attached
                        images violates an implementation-dependent set of
                        restrictions.
                    </p></dd></dl></div><p>
            If the currently bound framebuffer is not framebuffer complete, 
            then it is an error to attempt to use the framebuffer for
            writing or reading. This means that rendering commands
            (<a class="citerefentry" href="glClear.xml"><span class="citerefentry"><span class="refentrytitle">glClear</span></span></a>,
			<a class="citerefentry" href="glDrawArrays.xml"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>, and
            <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>)
            as well as commands that read the framebuffer
            (<a class="citerefentry" href="glReadPixels.xml"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a>,
            <a class="citerefentry" href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>, and
            <a class="citerefentry" href="glCopyTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>)
            will generate the error <code class="constant">GL_INVALID_FRAMEBUFFER_OPERATION</code>
            if called while the framebuffer is not framebuffer complete.
        </p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>
            It is strongly advised, thought not required, that an application
            call <code class="function">glCheckFramebufferStatus</code> to see if the
            framebuffer is complete prior to rendering. This is because some
            implementations may not support rendering to particular combinations
            of internal formats. In this case, 
            <code class="constant">GL_FRAMEBUFFER_UNSUPPORTED</code>
            is returned.
        </p><p>
            The default window-system-provided framebuffer is always
            framebuffer complete, and thus <code class="constant">GL_FRAMEBUFFER_COMPLETE</code>
            is returned when <code class="constant">GL_FRAMEBUFFER_BINDING</code> is 0.
        </p><p>
            Additionally, if an error occurs, zero is returned.
        </p></div><div class="refsect1"><a id="errors"></a><h2>Errors</h2><p>
            <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>target</code></em> is not <code class="constant">GL_FRAMEBUFFER</code>.
        </p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glBindRenderbuffer.xml"><span class="citerefentry"><span class="refentrytitle">glBindRenderbuffer</span></span></a>,
            <a class="citerefentry" href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,
            <a class="citerefentry" href="glCopyTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,
            <a class="citerefentry" href="glDrawArrays.xml"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
            <a class="citerefentry" href="glDrawElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
            <a class="citerefentry" href="glReadPixels.xml"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a>,
            <a class="citerefentry" href="glRenderbufferStorage.xml"><span class="citerefentry"><span class="refentrytitle">glRenderbufferStorage</span></span></a>
        </p></div><div class="refsect1"><a id="copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 2008 Khronos Group. 
            This material may be distributed subject to the terms and conditions set forth in 
            the Open Publication License, v 1.0, 8 June 1999.
            <a class="ulink" href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
        </p></div></div></body></html>