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<HTML><BODY><PRE>     <STRONG>NAME</STRONG>	  <STRONG>fglGetLightfv,</STRONG> <STRONG>fglGetLightiv</STRONG> - return	light source parameter	  values     <STRONG>FORTRAN</STRONG> <STRONG>SPECIFICATION</STRONG>	  SUBROUTINE <STRONG>fglGetLightfv</STRONG>( INTEGER*4 <EM>light</EM>,				    INTEGER*4 <EM>pname</EM>,				    CHARACTER*8	<EM>params</EM> )	  SUBROUTINE <STRONG>fglGetLightiv</STRONG>( INTEGER*4 <EM>light</EM>,				    INTEGER*4 <EM>pname</EM>,				    CHARACTER*8	<EM>params</EM> )     <STRONG>PARAMETERS</STRONG>	  <EM>light</EM>	  Specifies a light source.  The number	of possible		  lights depends on the	implementation,	but at least		  eight	lights are supported.  They are	identified by		  symbolic names of the	form <STRONG>GL_LIGHT</STRONG>i where 0 <EM>&lt;</EM> i &lt;		  <STRONG>GL_MAX_LIGHTS</STRONG>.	  <EM>pname</EM>	  Specifies a light source parameter for <EM>light</EM>.		  Accepted symbolic names are <STRONG>GL_AMBIENT</STRONG>, <STRONG>GL_DIFFUSE</STRONG>,		  <STRONG>GL_SPECULAR</STRONG>, <STRONG>GL_POSITION</STRONG>, <STRONG>GL_SPOT_DIRECTION</STRONG>,		  <STRONG>GL_SPOT_EXPONENT</STRONG>, <STRONG>GL_SPOT_CUTOFF</STRONG>,		  <STRONG>GL_CONSTANT_ATTENUATION</STRONG>, <STRONG>GL_LINEAR_ATTENUATION</STRONG> , and		  <STRONG>GL_QUADRATIC_ATTENUATION</STRONG>.	  <EM>params</EM>  Returns the requested	data.     <STRONG>DESCRIPTION</STRONG>	  <STRONG>fglGetLight</STRONG> returns in <EM>params</EM>	the value or values of a light	  source parameter.  <EM>light</EM> names the light and is a symbolic	  name of the form <STRONG>GL_LIGHT</STRONG>i for 0<EM>&lt;</EM>i&lt;<STRONG>GL_MAX_LIGHTS</STRONG>, where	  <STRONG>GL_MAX_LIGHTS</STRONG>	is an implementation dependent constant	that	  is greater than or equal to eight.  <EM>pname</EM> specifies one of	  ten light source parameters, again by	symbolic name.	  The following	parameters are defined:	  <STRONG>GL_AMBIENT</STRONG>	      <EM>params</EM> returns four integer or			      floating-point values representing the			      ambient intensity	of the light source.			      Integer values, when requested, are			      linearly mapped from the internal			      floating-point representation such that			      1.0 maps to the most positive			      representable integer value, and -1.0			      maps to the most negative	representable			      integer value.  If the internal value is			      outside the range	[-1, 1], the			      corresponding integer return value is			      undefined. The initial value is (0, 0,			      0, 1).	  <STRONG>GL_DIFFUSE</STRONG>	      <EM>params</EM> returns four integer or			      floating-point values representing the			      diffuse intensity	of the light source.			      Integer values, when requested, are			      linearly mapped from the internal			      floating-point representation such that			      1.0 maps to the most positive			      representable integer value, and -1.0			      maps to the most negative	representable			      integer value.  If the internal value is			      outside the range	[-1, 1], the			      corresponding integer return value is			      undefined. The initial value for			      <STRONG>GL_LIGHT0</STRONG>	is (1, 1, 1, 1); for other			      lights, the initial value	is (0, 0, 0,			      0).	  <STRONG>GL_SPECULAR</STRONG>	      <EM>params</EM> returns four integer or			      floating-point values representing the			      specular intensity of the	light source.			      Integer values, when requested, are			      linearly mapped from the internal			      floating-point representation such that			      1.0 maps to the most positive			      representable integer value, and -1.0			      maps to the most negative	representable			      integer value.  If the internal value is			      outside the range	[-1, 1], the			      corresponding integer return value is			      undefined. The initial value for			      <STRONG>GL_LIGHT0</STRONG>	is (1, 1, 1, 1); for other			      lights, the initial value	is (0, 0, 0,			      0).	  <STRONG>GL_POSITION</STRONG>	      <EM>params</EM> returns four integer or			      floating-point values representing the			      position of the light source.  Integer			      values, when requested, are computed by			      rounding the internal floating-point			      values to	the nearest integer value.			      The returned values are those maintained			      in eye coordinates.  They	will not be			      equal to the values specified using			      <STRONG>fglLight</STRONG>,	unless the modelview matrix			      was identity at the time <STRONG>fglLight</STRONG>	was			      called. The initial value	is (0, 0, 1,			      0).	  <STRONG>GL_SPOT_DIRECTION</STRONG>   <EM>params</EM> returns three integer or			      floating-point values representing the			      direction	of the light source.  Integer			      values, when requested, are computed by			      rounding the internal floating-point			      values to	the nearest integer value.			      The returned values are those maintained			      in eye coordinates.  They	will not be			      equal to the values specified using			      <STRONG>fglLight</STRONG>,	unless the modelview matrix			      was identity at the time <STRONG>fglLight</STRONG>	was			      called.  Although	spot direction is			      normalized before	being used in the			      lighting equation, the returned values			      are the transformed versions of the			      specified	values prior to	normalization.			      The initial value	is (0, 0, -1).	  <STRONG>GL_SPOT_EXPONENT</STRONG>    <EM>params</EM> returns a single integer or			      floating-point value representing	the			      spot exponent of the light.  An integer			      value, when requested, is	computed by			      rounding the internal floating-point			      representation to	the nearest integer.			      The initial value	is 0.	  <STRONG>GL_SPOT_CUTOFF</STRONG>      <EM>params</EM> returns a single integer or			      floating-point value representing	the			      spot cutoff angle	of the light.  An			      integer value, when requested, is			      computed by rounding the internal			      floating-point representation to the			      nearest integer. The initial value is			      180.	  <STRONG>GL_CONSTANT_ATTENUATION</STRONG>			      <EM>params</EM> returns a single integer or			      floating-point value representing	the			      constant (not distance-related)			      attenuation of the light.	 An integer			      value, when requested, is	computed by			      rounding the internal floating-point			      representation to	the nearest integer.			      The initial value	is 1.	  <STRONG>GL_LINEAR_ATTENUATION</STRONG>			      <EM>params</EM> returns a single integer or			      floating-point value representing	the			      linear attenuation of the	light.	An			      integer value, when requested, is			      computed by rounding the internal			      floating-point representation to the			      nearest integer. The initial value is 0.	  <STRONG>GL_QUADRATIC_ATTENUATION</STRONG>			      <EM>params</EM> returns a single integer or			      floating-point value representing	the			      quadratic	attenuation of the light.  An			      integer value, when requested, is			      computed by rounding the internal			      floating-point representation to the			      nearest integer. The initial value is 0.     <STRONG>NOTES</STRONG>	  It is	always the case	that <STRONG>GL_LIGHT</STRONG>i = <STRONG>GL_LIGHT0</STRONG> + i.	  If an	error is generated, no change is made to the contents	  of <EM>params</EM>.     <STRONG>ERRORS</STRONG>	  <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>light</EM>	or <EM>pname</EM> is not	an	  accepted value.	  <STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>fglGetLight</STRONG> is executed	  between the execution	of <STRONG>fglBegin</STRONG> and	the corresponding	  execution of <STRONG>fglEnd</STRONG>.     <STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>	  <STRONG>fglLight</STRONG></PRE></BODY></HTML>
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