[clinton/guile-figl.git] / upstream-doc / manglsl / gl_SamplePosition.xml

<?xml version="1.0" encoding="UTF-8"?>\r
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"\r
              "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">\r
<refentry id="gl_SamplePosition">\r
    <refmeta>\r
        <refmetainfo>\r
            <copyright>\r
                <year>2011</year>\r
                <holder>Khronos Group</holder>\r
            </copyright>\r
        </refmetainfo>\r
        <refentrytitle>gl_SamplePosition</refentrytitle>\r
        <manvolnum>3G</manvolnum>\r
    </refmeta>\r
    <refnamediv>\r
        <refname>gl_SamplePosition</refname>\r
        <refpurpose>contains the location of the current sample within the current fragment</refpurpose>\r
    </refnamediv>\r
    <refsynopsisdiv><title>Declaration</title>\r
        <funcsynopsis>\r
            <function>in vec2 gl_SamplePosition;</function>\r
        </funcsynopsis>\r
    </refsynopsisdiv>\r
    <refsect1 id="description"><title>Description</title>\r
        <para>\r
            <function>gl_SamplePosition</function> is a fragment language input variable that contains\r
            the location within a fragment of the sample currently being processed. The x and y components\r
            of <function>gl_SamplePosition</function> contain the sub-pixel coordinate of the current\r
            sample and will have values in the range 0.0 to 1.0. The sub-pixel coordinates of the center\r
            of the pixel are always (0.5, 0.5). Any static use of <function>gl_SamplePosition</function>\r
            causes the entire fragment shader to be evaluated per-sample rather than per-fragment. When rendering\r
            to a non-multisample buffer, or if multisample rasterization is disabled, <function>gl_SamplePosition</function>\r
            will be (0.5, 0.5).\r
        </para>\r
    </refsect1>\r
    <refsect1 id="versions"><title>Version Support</title>\r
        <informaltable frame="topbot">\r
            <tgroup cols="3" align="left">\r
                <colspec colwidth="1.1*" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <colspec colwidth="1*" align="center" />\r
                <thead>\r
                    <row>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Variable\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 1.10\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 1.20\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 1.30\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 1.40\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 1.50\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 3.30\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 4.00\r
                        </emphasis></entry>\r
                        <entry rowsep="1" align="left"><emphasis role="bold">\r
                        Version 4.10\r
                        </emphasis></entry>\r
                    </row>\r
                    <row>\r
                        <entry>\r
                            gl_SamplePosition\r
                        </entry>\r
                        <entry>\r
                            <emphasis>-</emphasis>  <!-- 1.10, OpenGL 2.0 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>-</emphasis>  <!-- 1.20, OpenGL 2.1 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>-</emphasis>  <!-- 1.30, OpenGL 3.0 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>-</emphasis>  <!-- 1.40, OpenGL 3.1 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>-</emphasis>  <!-- 1.50, OpenGL 3.2 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>-</emphasis>  <!-- 3.30, OpenGL 3.3 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>Y</emphasis>  <!-- 4.00, OpenGL 4.0 -->\r
                        </entry>\r
                        <entry>\r
                            <emphasis>Y</emphasis>  <!-- 4.10, OpenGL 4.1 -->\r
                        </entry>\r
                    </row>\r
                </thead>\r
            </tgroup>\r
        </informaltable>\r
    </refsect1>\r
    <refsect1 id="seealso"><title>See Also</title>\r
        <para>\r
            <citerefentry><refentrytitle>gl_SampleID</refentrytitle></citerefentry>,\r
            <citerefentry><refentrytitle>gl_SampleMask</refentrytitle></citerefentry>,\r
            <citerefentry><refentrytitle>gl_FragCoord</refentrytitle></citerefentry>\r
        </para>\r
    </refsect1>\r
    <refsect1 id="Copyright"><title>Copyright</title>\r
        <para>\r
            Copyright <trademark class="copyright"></trademark> 2011 Khronos Group. \r
            This material may be distributed subject to the terms and conditions set forth in \r
            the Open Publication License, v 1.0, 8 June 1999.\r
            <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.\r
        </para>\r
    </refsect1>\r
</refentry>\r
Commit	Line	Data
7faf1d71 AW	1	<?xml version="1.0" encoding="UTF-8"?>\r
	2	<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"\r
	3	"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">\r
	4	<refentry id="gl_SamplePosition">\r
	5	<refmeta>\r
	6	<refmetainfo>\r
	7	<copyright>\r
	8	<year>2011</year>\r
	9	<holder>Khronos Group</holder>\r
	10	</copyright>\r
	11	</refmetainfo>\r
	12	<refentrytitle>gl_SamplePosition</refentrytitle>\r
	13	<manvolnum>3G</manvolnum>\r
	14	</refmeta>\r
	15	<refnamediv>\r
	16	<refname>gl_SamplePosition</refname>\r
	17	<refpurpose>contains the location of the current sample within the current fragment</refpurpose>\r
	18	</refnamediv>\r
	19	<refsynopsisdiv><title>Declaration</title>\r
	20	<funcsynopsis>\r
	21	<function>in vec2 gl_SamplePosition;</function>\r
	22	</funcsynopsis>\r
	23	</refsynopsisdiv>\r
	24	<refsect1 id="description"><title>Description</title>\r
	25	<para>\r
	26	<function>gl_SamplePosition</function> is a fragment language input variable that contains\r
	27	the location within a fragment of the sample currently being processed. The x and y components\r
	28	of <function>gl_SamplePosition</function> contain the sub-pixel coordinate of the current\r
	29	sample and will have values in the range 0.0 to 1.0. The sub-pixel coordinates of the center\r
	30	of the pixel are always (0.5, 0.5). Any static use of <function>gl_SamplePosition</function>\r
	31	causes the entire fragment shader to be evaluated per-sample rather than per-fragment. When rendering\r
	32	to a non-multisample buffer, or if multisample rasterization is disabled, <function>gl_SamplePosition</function>\r
	33	will be (0.5, 0.5).\r
	34	</para>\r
	35	</refsect1>\r
	36	<refsect1 id="versions"><title>Version Support</title>\r
	37	<informaltable frame="topbot">\r
	38	<tgroup cols="3" align="left">\r
	39	<colspec colwidth="1.1*" />\r
	40	<colspec colwidth="1*" align="center" />\r
	41	<colspec colwidth="1*" align="center" />\r
	42	<colspec colwidth="1*" align="center" />\r
	43	<colspec colwidth="1*" align="center" />\r
	44	<colspec colwidth="1*" align="center" />\r
	45	<colspec colwidth="1*" align="center" />\r
	46	<colspec colwidth="1*" align="center" />\r
	47	<colspec colwidth="1*" align="center" />\r
	48	<thead>\r
	49	<row>\r
	50	<entry rowsep="1" align="left"><emphasis role="bold">\r
	51	Variable\r
	52	</emphasis></entry>\r
	53	<entry rowsep="1" align="left"><emphasis role="bold">\r
	54	Version 1.10\r
	55	</emphasis></entry>\r
	56	<entry rowsep="1" align="left"><emphasis role="bold">\r
	57	Version 1.20\r
	58	</emphasis></entry>\r
	59	<entry rowsep="1" align="left"><emphasis role="bold">\r
	60	Version 1.30\r
	61	</emphasis></entry>\r
	62	<entry rowsep="1" align="left"><emphasis role="bold">\r
	63	Version 1.40\r
	64	</emphasis></entry>\r
65	<entry rowsep="1" align="left"><emphasis role="bold">\r
66	Version 1.50\r
67	</emphasis></entry>\r
68	<entry rowsep="1" align="left"><emphasis role="bold">\r
69	Version 3.30\r
70	</emphasis></entry>\r
71	<entry rowsep="1" align="left"><emphasis role="bold">\r
72	Version 4.00\r
73	</emphasis></entry>\r
74	<entry rowsep="1" align="left"><emphasis role="bold">\r
75	Version 4.10\r
76	</emphasis></entry>\r
77	</row>\r
78	<row>\r
79	<entry>\r
80	gl_SamplePosition\r
81	</entry>\r
82	<entry>\r
83	<emphasis>-</emphasis> <!-- 1.10, OpenGL 2.0 -->\r
84	</entry>\r
85	<entry>\r
86	<emphasis>-</emphasis> <!-- 1.20, OpenGL 2.1 -->\r
87	</entry>\r
88	<entry>\r
89	<emphasis>-</emphasis> <!-- 1.30, OpenGL 3.0 -->\r
90	</entry>\r
91	<entry>\r
92	<emphasis>-</emphasis> <!-- 1.40, OpenGL 3.1 -->\r
93	</entry>\r
94	<entry>\r
95	<emphasis>-</emphasis> <!-- 1.50, OpenGL 3.2 -->\r
96	</entry>\r
97	<entry>\r
98	<emphasis>-</emphasis> <!-- 3.30, OpenGL 3.3 -->\r
99	</entry>\r
100	<entry>\r
101	<emphasis>Y</emphasis> <!-- 4.00, OpenGL 4.0 -->\r
102	</entry>\r
103	<entry>\r
104	<emphasis>Y</emphasis> <!-- 4.10, OpenGL 4.1 -->\r
105	</entry>\r
106	</row>\r
107	</thead>\r
108	</tgroup>\r
109	</informaltable>\r
110	</refsect1>\r
111	<refsect1 id="seealso"><title>See Also</title>\r
112	<para>\r
113	<citerefentry><refentrytitle>gl_SampleID</refentrytitle></citerefentry>,\r
114	<citerefentry><refentrytitle>gl_SampleMask</refentrytitle></citerefentry>,\r
115	<citerefentry><refentrytitle>gl_FragCoord</refentrytitle></citerefentry>\r
116	</para>\r
117	</refsect1>\r
118	<refsect1 id="Copyright"><title>Copyright</title>\r
119	<para>\r
120	Copyright <trademark class="copyright"></trademark> 2011 Khronos Group. \r
121	This material may be distributed subject to the terms and conditions set forth in \r
122	the Open Publication License, v 1.0, 8 June 1999.\r
123	<ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.\r
124	</para>\r
125	</refsect1>\r
126	</refentry>\r