Opentk/Source/Bind/Specifications/Docs/glClearBuffer.xml
Stefanos A 60f971ffed Updated to the latest gl4 specs and docs
Large code-drop from Khronos upstream.
2013-11-03 12:43:50 +01:00

171 lines
9.2 KiB
XML

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
<refentry id="glClearBuffer">
<refentryinfo>
<copyright>
<year>2010-2013</year>
<holder>Khronos Group</holder>
</copyright>
</refentryinfo>
<refmeta>
<refentrytitle>glClearBuffer</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glClearBuffer</refname>
<refpurpose>clear individual buffers of the currently bound draw framebuffer</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glClearBufferiv</function></funcdef>
<paramdef>GLenum <parameter>buffer</parameter></paramdef>
<paramdef>GLint <parameter>drawBuffer</parameter></paramdef>
<paramdef>const GLint * <parameter>value</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glClearBufferuiv</function></funcdef>
<paramdef>GLenum <parameter>buffer</parameter></paramdef>
<paramdef>GLint <parameter>drawBuffer</parameter></paramdef>
<paramdef>const GLuint * <parameter>value</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glClearBufferfv</function></funcdef>
<paramdef>GLenum <parameter>buffer</parameter></paramdef>
<paramdef>GLint <parameter>drawBuffer</parameter></paramdef>
<paramdef>const GLfloat * <parameter>value</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glClearBufferfi</function></funcdef>
<paramdef>GLenum <parameter>buffer</parameter></paramdef>
<paramdef>GLint <parameter>drawBuffer</parameter></paramdef>
<paramdef>GLfloat <parameter>depth</parameter></paramdef>
<paramdef>GLint <parameter>stencil</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>buffer</parameter></term>
<listitem>
<para>
Specify the buffer to clear.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>drawBuffer</parameter></term>
<listitem>
<para>
Specify a particular draw buffer to clear.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>value</parameter></term>
<listitem>
<para>
For color buffers, a pointer to a four-element vector specifying R, G, B and A values to clear the buffer to.
For depth buffers, a pointer to a single depth value to clear the buffer to.
For stencil buffers, a pointer to a single stencil value to clear the buffer to.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>depth</parameter></term>
<listitem>
<para>
The value to clear a depth render buffer to.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>stencil</parameter></term>
<listitem>
<para>
The value to clear a stencil render buffer to.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="description"><title>Description</title>
<para>
<function>glClearBuffer*</function> clears the specified buffer to the specified value(s). If <parameter>buffer</parameter> is
<constant>GL_COLOR</constant>, a particular draw buffer <constant>GL_DRAW_BUFFER</constant><parameter>i</parameter> is specified
by passing <parameter>i</parameter> as <parameter>drawBuffer</parameter>. In this case, <parameter>value</parameter> points to
a four-element vector specifying the R, G, B and A color to clear that draw buffer to. If <parameter>buffer</parameter> is
one of <constant>GL_FRONT</constant>, <constant>GL_BACK</constant>, <constant>GL_LEFT</constant>, <constant>GL_RIGHT</constant>,
or <constant>GL_FRONT_AND_BACK</constant>, identifying multiple buffers, each selected buffer is cleared to the same value.
Clamping and conversion for fixed-point color buffers are performed in the same fashion as
<citerefentry><refentrytitle>glClearColor</refentrytitle></citerefentry>.
</para>
<para>
If <parameter>buffer</parameter> is <constant>GL_DEPTH</constant>, <parameter>drawBuffer</parameter> must be zero, and <parameter>value</parameter>
points to a single value to clear the depth buffer to. Only <function>glClearBufferfv</function> should be used to clear
depth buffers. Clamping and conversion for fixed-point depth buffers are performed in the same fashion as
<citerefentry><refentrytitle>glClearDepth</refentrytitle></citerefentry>.
</para>
<para>
If <parameter>buffer</parameter> is <constant>GL_STENCIL</constant>, <parameter>drawBuffer</parameter> must be zero, and <parameter>value</parameter>
points to a single value to clear the stencil buffer to. Only <function>glClearBufferiv</function> should be used to clear
stencil buffers. Masking and type conversion are performed in the same fashion as
<citerefentry><refentrytitle>glClearStencil</refentrytitle></citerefentry>.
</para>
<para>
<function>glClearBufferfi</function> may be used to clear the depth and stencil buffers. <parameter>buffer</parameter> must be
<constant>GL_DEPTH_STENCIL</constant> and <parameter>drawBuffer</parameter> must be zero. <parameter>depth</parameter> and
<parameter>stencil</parameter> are the depth and stencil values, respectively.
</para>
<para>
The result of <function>glClearBuffer</function> is undefined if no conversion between the type of <parameter>value</parameter>
and the buffer being cleared is defined. However, this is not an error.
</para>
</refsect1>
<refsect1 id="errors"><title>Errors</title>
<para>
<constant>GL_INVALID_ENUM</constant> is generated by <function>glClearBufferif</function>, <function>glClearBufferfv</function>
and <function>glClearBufferuiv</function> if <parameter>buffer</parameter> is not <constant>GL_COLOR</constant>,
<constant>GL_FRONT</constant>, <constant>GL_BACK</constant>, <constant>GL_LEFT</constant>, <constant>GL_RIGHT</constant>,
<constant>GL_FRONT_AND_BACK</constant>, <constant>GL_DEPTH</constant> or <constant>GL_STENCIL</constant>.
</para>
<para>
<constant>GL_INVALID_ENUM</constant> is generated by <function>glClearBufferfi</function> if <parameter>buffer</parameter>
is not <constant>GL_DEPTH_STENCIL</constant>.
</para>
<para>
<constant>GL_INVALID_VALUE</constant> is generated if <parameter>buffer</parameter> is <constant>GL_COLOR</constant>,
<constant>GL_FRONT</constant>, <constant>GL_BACK</constant>, <constant>GL_LEFT</constant>, <constant>GL_RIGHT</constant>,
or <constant>GL_FRONT_AND_BACK</constant> and <parameter>drawBuffer</parameter> is greater than or equal to <constant>GL_MAX_DRAW_BUFFERS</constant>.
</para>
<para>
<constant>GL_INVALID_VALUE</constant> is generated if <parameter>buffer</parameter> is <constant>GL_DEPTH</constant>,
<constant>GL_STENCIL</constant> or <constant>GL_DEPTH_STENCIL</constant> and <parameter>drawBuffer</parameter> is not zero.
</para>
</refsect1>
<refsect1 id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>glClearColor</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glClearDepth</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glClearStencil</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>glClear</refentrytitle></citerefentry>
</para>
</refsect1>
<refsect1 id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"></trademark> 2010-2013 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.
<ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
</para>
</refsect1>
</refentry>