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<HTML><BODY><PRE>     <STRONG>NAME</STRONG>	  <STRONG>fglTexImage2D</STRONG>	- specify a two-dimensional texture image     <STRONG>FORTRAN</STRONG> <STRONG>SPECIFICATION</STRONG>	  SUBROUTINE <STRONG>fglTexImage2D</STRONG>( INTEGER*4 <EM>target</EM>,				    INTEGER*4 <EM>level</EM>,				    INTEGER*4 <EM>internalformat</EM>,				    INTEGER*4 <EM>width</EM>,				    INTEGER*4 <EM>height</EM>,				    INTEGER*4 <EM>border</EM>,				    INTEGER*4 <EM>format</EM>,				    INTEGER*4 <EM>type</EM>,				    CHARACTER*8	<EM>pixels</EM> )     <STRONG>PARAMETERS</STRONG>	  <EM>target</EM>	  Specifies the	target texture.	 Must be			  <STRONG>GL_TEXTURE_2D</STRONG>	or <STRONG>GL_PROXY_TEXTURE_2D</STRONG>.	  <EM>level</EM>		  Specifies the	level-of-detail	number.	 Level			  0 is the base	image level.  Level <EM>n</EM> is the			  <EM>n</EM>th mipmap reduction image.	  <EM>internalformat</EM>  Specifies the	number of color	components in			  the texture.	Must be	1, 2, 3, or 4, or one			  of the following symbolic constants:			  <STRONG>GL_ALPHA</STRONG>, <STRONG>GL_ALPHA4</STRONG>, <STRONG>GL_ALPHA8</STRONG>, <STRONG>GL_ALPHA12</STRONG>,			  <STRONG>GL_ALPHA16</STRONG>, <STRONG>GL_LUMINANCE</STRONG>, <STRONG>GL_LUMINANCE4</STRONG>,			  <STRONG>GL_LUMINANCE8</STRONG>, <STRONG>GL_LUMINANCE12</STRONG>,			  <STRONG>GL_LUMINANCE16</STRONG>, <STRONG>GL_LUMINANCE_ALPHA</STRONG>,			  <STRONG>GL_LUMINANCE4_ALPHA4</STRONG>,	<STRONG>GL_LUMINANCE6_ALPHA2</STRONG>,			  <STRONG>GL_LUMINANCE8_ALPHA8</STRONG>,	<STRONG>GL_LUMINANCE12_ALPHA4</STRONG>,			  <STRONG>GL_LUMINANCE12_ALPHA12</STRONG>,			  <STRONG>GL_LUMINANCE16_ALPHA16</STRONG>, <STRONG>GL_INTENSITY</STRONG>,			  <STRONG>GL_INTENSITY4</STRONG>, <STRONG>GL_INTENSITY8</STRONG>,			  <STRONG>GL_INTENSITY12</STRONG>, <STRONG>GL_INTENSITY16</STRONG>, <STRONG>GL_R3_G3_B2</STRONG>,			  <STRONG>GL_RGB</STRONG>, <STRONG>GL_RGB4</STRONG>, <STRONG>GL_RGB5</STRONG>, <STRONG>GL_RGB8</STRONG>, <STRONG>GL_RGB10</STRONG>,			  <STRONG>GL_RGB12</STRONG>, <STRONG>GL_RGB16</STRONG>, <STRONG>GL_RGBA</STRONG>, <STRONG>GL_RGBA2</STRONG>,			  <STRONG>GL_RGBA4</STRONG>, <STRONG>GL_RGB5_A1</STRONG>,	<STRONG>GL_RGBA8</STRONG>, <STRONG>GL_RGB10_A2</STRONG>,			  <STRONG>GL_RGBA12</STRONG>, or	<STRONG>GL_RGBA16</STRONG>.	  <EM>width</EM>		  Specifies the	width of the texture image.			  Must be 2n+2(border) for some	integer	n. All			  implementations support texture images that			  are at least 64 texels wide.	  <EM>height</EM>	  Specifies the	height of the texture image.			  Must be 2m+2(border) for some	integer	m. All			  implementations support texture images that			  are at least 64 texels high.	  <EM>border</EM>	  Specifies the	width of the border.  Must be			  either 0 or 1.	  <EM>format</EM>	  Specifies the	format of the pixel data.  The			  following symbolic values are	accepted:			  <STRONG>GL_COLOR_INDEX</STRONG>, <STRONG>GL_RED</STRONG>, <STRONG>GL_GREEN</STRONG>, <STRONG>GL_BLUE</STRONG>,			  <STRONG>GL_ALPHA</STRONG>, <STRONG>GL_RGB</STRONG>, <STRONG>GL_RGBA</STRONG>, <STRONG>GL_LUMINANCE</STRONG>, and			  <STRONG>GL_LUMINANCE_ALPHA</STRONG>.	  <EM>type</EM>		  Specifies the	data type of the pixel data.			  The following	symbolic values	are accepted:			  <STRONG>GL_UNSIGNED_BYTE</STRONG>, <STRONG>GL_BYTE</STRONG>, <STRONG>GL_BITMAP</STRONG>,			  <STRONG>GL_UNSIGNED_SHORT</STRONG>, <STRONG>GL_SHORT</STRONG>,			  <STRONG>GL_UNSIGNED_INT</STRONG>, <STRONG>GL_INT</STRONG>, and <STRONG>GL_FLOAT</STRONG>.	  <EM>pixels</EM>	  Specifies a pointer to the image data	in			  memory.     <STRONG>DESCRIPTION</STRONG>	  Texturing maps a portion of a	specified texture image	onto	  each graphical primitive for which texturing is enabled.  To	  enable and disable two-dimensional texturing,	call <STRONG>fglEnable</STRONG>	  and <STRONG>fglDisable</STRONG> with argument <STRONG>GL_TEXTURE_2D</STRONG>.	  To define texture images, call <STRONG>fglTexImage2D</STRONG>.	The arguments	  describe the parameters of the texture image,	such as	  height, width, width of the border, level-of-detail number	  (see <STRONG>fglTexParameter</STRONG>), and number of color components	  provided.  The last three arguments describe how the image	  is represented in memory; they are identical to the pixel	  formats used for <STRONG>fglDrawPixels</STRONG>.	  If <EM>target</EM> is <STRONG>GL_PROXY_TEXTURE_2D</STRONG>, no data is read from	  <EM>pixels</EM>, but all of the texture image state is	recalculated,	  checked for consistency, and checked against the	  implementation's capabilities. If the	implementation cannot	  handle a texture of the requested texture size, it sets all	  of the image state to	0, but does not	generate an error (see	  <STRONG>fglGetError</STRONG>).	To query for an	entire mipmap array, use an	  image	array level greater than or equal to 1.	  If <EM>target</EM> is <STRONG>GL_TEXTURE_2D</STRONG>, data is read from	<EM>pixels</EM> as a	  sequence of signed or	unsigned bytes,	shorts,	or longs, or	  single-precision floating-point values, depending on <EM>type</EM>.	  These	values are grouped into	sets of	one, two, three, or	  four values, depending on <EM>format</EM>, to form elements. If <EM>type</EM>	  is <STRONG>GL_BITMAP</STRONG>,	the data is considered as a string of unsigned	  bytes	(and <EM>format</EM> must be <STRONG>GL_COLOR_INDEX</STRONG>). Each data byte is	  treated as eight 1-bit elements, with	bit ordering	  determined by	<STRONG>GL_UNPACK_LSB_FIRST</STRONG> (see <STRONG>fglPixelStore</STRONG>).	  The first element corresponds	to the lower left corner of	  the texture image.  Subsequent elements progress left-to-	  right	through	the remaining texels in	the lowest row of the	  texture image, and then in successively higher rows of the	  texture image.  The final element corresponds	to the upper	  right	corner of the texture image.	  <EM>format</EM> determines the	composition of each element in <EM>pixels</EM>.	  It can assume	one of nine symbolic values:	  <STRONG>GL_COLOR_INDEX</STRONG>		    Each element is a single value, a color index. The		    GL converts	it to fixed point (with	an unspecified		    number of zero bits	to the right of	the binary		    point), shifted left or right depending on the		    value and sign of <STRONG>GL_INDEX_SHIFT</STRONG>, and added	to		    <STRONG>GL_INDEX_OFFSET</STRONG> (see		    <STRONG>fglPixelTransfer</STRONG>). The resulting index is		    converted to a set of color	components using the		    <STRONG>GL_PIXEL_MAP_I_TO_R</STRONG>, <STRONG>GL_PIXEL_MAP_I_TO_G</STRONG>,		    <STRONG>GL_PIXEL_MAP_I_TO_B</STRONG>, and <STRONG>GL_PIXEL_MAP_I_TO_A</STRONG>		    tables, and	clamped	to the range [0,1].	  <STRONG>GL_RED</STRONG>    Each element is a single red component. The	GL		    converts it	to floating point and assembles	it		    into an RGBA element by attaching 0	for green and		    blue, and 1	for alpha. Each	component is then		    multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,		    added to the signed	bias <STRONG>GL_c_BIAS</STRONG>,	and clamped to		    the	range [0,1] (see <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_GREEN</STRONG>  Each element is a single green component. The GL		    converts it	to floating point and assembles	it		    into an RGBA element by attaching 0	for red	and		    blue, and 1	for alpha. Each	component is then		    multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,		    added to the signed	bias <STRONG>GL_c_BIAS</STRONG>,	and clamped to		    the	range [0,1] (see <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_BLUE</STRONG>   Each element is a single blue component. The GL		    converts it	to floating point and assembles	it		    into an RGBA element by attaching 0	for red	and		    green, and 1 for alpha. Each component is then		    multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,		    added to the signed	bias <STRONG>GL_c_BIAS</STRONG>,	and clamped to		    the	range [0,1] (see <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_ALPHA</STRONG>  Each element is a single alpha component. The GL		    converts it	to floating point and assembles	it		    into an RGBA element by attaching 0	for red,		    green, and blue.  Each component is	then		    multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,		    added to the signed	bias <STRONG>GL_c_BIAS</STRONG>,	and clamped to		    the	range [0,1] (see <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_RGB</STRONG>    Each element is an RGB triple.  The	GL converts it		    to floating	point and assembles it into an RGBA		    element by attaching 1 for alpha.  Each component		    is then multiplied by the signed scale factor		    <STRONG>GL_c_SCALE</STRONG>,	added to the signed bias <STRONG>GL_c_BIAS</STRONG>,		    and	clamped	to the range [0,1] (see		    <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_RGBA</STRONG>   Each element contains all four components.	Each		    component is multiplied by the signed scale	factor		    <STRONG>GL_c_SCALE</STRONG>,	added to the signed bias <STRONG>GL_c_BIAS</STRONG>,		    and	clamped	to the range [0,1] (see		    <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_LUMINANCE</STRONG>		    Each element is a single luminance value.  The GL		    converts it	to floating point, then	assembles it		    into an RGBA element by replicating	the luminance		    value three	times for red, green, and blue and		    attaching 1	for alpha. Each	component is then		    multiplied by the signed scale factor <STRONG>GL_c_SCALE</STRONG>,		    added to the signed	bias <STRONG>GL_c_BIAS</STRONG>,	and clamped to		    the	range [0,1] (see <STRONG>fglPixelTransfer</STRONG>).	  <STRONG>GL_LUMINANCE_ALPHA</STRONG>		    Each element is a luminance/alpha pair.  The GL		    converts it	to floating point, then	assembles it		    into an RGBA element by replicating	the luminance		    value three	times for red, green, and blue.	 Each		    component is then multiplied by the	signed scale		    factor <STRONG>GL_c_SCALE</STRONG>, added to	the signed bias		    <STRONG>GL_c_BIAS</STRONG>, and clamped to the range	[0,1] (see		    <STRONG>fglPixelTransfer</STRONG>).	  Refer	to the <STRONG>fglDrawPixels</STRONG> reference page for	a description	  of the acceptable values for the <EM>type</EM>	parameter.	  If an	application wants to store the texture at a certain	  resolution or	in a certain format, it	can request the	  resolution and format	with <EM>internalformat</EM>. The GL will	  choose an internal representation that closely approximates	  that requested by <EM>internalformat</EM>, but	it may not match	  exactly.  (The representations specified by <STRONG>GL_LUMINANCE</STRONG>,	  <STRONG>GL_LUMINANCE_ALPHA</STRONG>, <STRONG>GL_RGB</STRONG>, and <STRONG>GL_RGBA</STRONG> must match exactly.	  The numeric values 1,	2, 3, and 4 may	also be	used to	  specify the above representations.)	  Use the <STRONG>GL_PROXY_TEXTURE_2D</STRONG> target to	try out	a resolution	  and format. The implementation will update and recompute its	  best match for the requested storage resolution and format.	  To then query	this state, call <STRONG>fglGetTexLevelParameter</STRONG>.  If	  the texture cannot be	accommodated, texture state is set to	  0.	  A one-component texture image	uses only the red component of	  the RGBA color extracted from	<EM>pixels</EM>.	A two-component	image	  uses the R and A values.  A three-component image uses the	  R, G,	and B values.  A four-component	image uses all of the	  RGBA components.     <STRONG>NOTES</STRONG>	  Texturing has	no effect in color index mode.	  The texture image can	be represented by the same data	  formats as the pixels	in a <STRONG>fglDrawPixels</STRONG> command, except	  that <STRONG>GL_STENCIL_INDEX</STRONG>	and <STRONG>GL_DEPTH_COMPONENT</STRONG> cannot be used.	  <STRONG>fglPixelStore</STRONG>	and <STRONG>fglPixelTransfer</STRONG> modes affect texture	  images in exactly the	way they affect	<STRONG>fglDrawPixels</STRONG>.	  <STRONG>fglTexImage2D</STRONG>	and <STRONG>GL_PROXY_TEXTURE_2D</STRONG>	are only available if	  the GL version is 1.1	or greater.	  Internal formats other than 1, 2, 3, or 4 may	only be	used	  if the GL version is 1.1 or greater.	  In GL	version	1.1 or greater,	<EM>pixels</EM> may be a	null pointer.	  In this case texture memory is allocated to accommodate a	  texture of width <EM>width</EM> and height <EM>height</EM>.  You can then	  download subtextures to initialize this texture memory. The	  image	is undefined if	the user tries to apply	an	  uninitialized	portion	of the texture image to	a primitive.     <STRONG>ERRORS</STRONG>	  <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>target</EM> is not	<STRONG>GL_TEXTURE_2D</STRONG>	  or <STRONG>GL_PROXY_TEXTURE_2D</STRONG>.	  <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>format</EM> is not	an accepted	  format constant.  Format constants other than	  <STRONG>GL_STENCIL_INDEX</STRONG> and <STRONG>GL_DEPTH_COMPONENT</STRONG> are accepted.	  <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>type</EM> is not a	type constant.	  <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>type</EM> is <STRONG>GL_BITMAP</STRONG> and	<EM>format</EM>	  is not <STRONG>GL_COLOR_INDEX</STRONG>.	  <STRONG>GL_INVALID_VALUE</STRONG> is generated	if <EM>level</EM> is less than 0.	  <STRONG>GL_INVALID_VALUE</STRONG> may be generated if <EM>level</EM> is	greater	than	  log <EM>max</EM>, where <EM>max</EM> is	the returned value of	  <STRONG>GL_MAX_TEXTURE_SIZE</STRONG>.	  <STRONG>GL_INVALID_VALUE</STRONG> is generated	if <EM>internalformat</EM> is not 1, 2,	  3, 4,	or one of the accepted resolution and format symbolic	  constants.	  <STRONG>GL_INVALID_VALUE</STRONG> is generated	if <EM>width</EM> or <EM>height</EM> is less	  than 0 or greater than 2 + <STRONG>GL_MAX_TEXTURE_SIZE</STRONG>, or if	either	  cannot be represented	as 2k+2(border)	for some integer value	  of <EM>k</EM>.	  <STRONG>GL_INVALID_VALUE</STRONG> is generated	if <EM>border</EM> is not 0 or 1.	  <STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>fglTexImage2D</STRONG> is	  executed between the execution of <STRONG>fglBegin</STRONG> and the	  corresponding	execution of <STRONG>fglEnd</STRONG>.     <STRONG>ASSOCIATED</STRONG>	<STRONG>GETS</STRONG>	  <STRONG>fglGetTexImage</STRONG>	  <STRONG>fglIsEnabled</STRONG> with argument <STRONG>GL_TEXTURE_2D</STRONG>     <STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>	  <STRONG>fglCopyPixels</STRONG>, <STRONG>fglCopyTexImage1D</STRONG>, <STRONG>fglCopyTexImage2D</STRONG>,	  <STRONG>fglCopyTexSubImage1D</STRONG>,	<STRONG>fglCopyTexSubImage2D</STRONG>, <STRONG>fglDrawPixels</STRONG>,	  <STRONG>fglPixelStore</STRONG>, <STRONG>fglPixelTransfer</STRONG>, <STRONG>fglTexEnv</STRONG>, <STRONG>fglTexGen</STRONG>,	  <STRONG>fglTexImage1D</STRONG>, <STRONG>fglTexSubImage1D</STRONG>, <STRONG>fglTexSubImage2D</STRONG>,	  <STRONG>fglTexParameter</STRONG></PRE></BODY></HTML>
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