pp_addpm({At=>Top},<<'EOD');
=head1 NAME

	PDL::Graphics::OpenGLQ - quick routines to plot lots of stuff from piddles.

=head1 SYNOPSIS

	only for internal use - see source

=head1 DESCRIPTION

only for internal use - see source

=head1 AUTHOR

Copyright (C) 1997,1998 Tuomas J. Lukka.  
All rights reserved. There is no warranty. You are allowed
to redistribute this software / documentation under certain
conditions. For details, see the file COPYING in the PDL 
distribution. If this file is separated from the PDL distribution, 
the copyright notice should be included in the file.


=cut


EOD

pp_addhdr('
#ifdef HAVE_AGL_GLUT
#include <OpenGL/gl.h>
#include <OpenGL/glu.h>
#else
#include <GL/gl.h>
#include <GL/glu.h>
#endif
/* #include <GL/glx.h> */

/* #include "../OpenGL/OpenGL.m" */
/* D_OPENGL; */
');

#pp_add_boot('
#	I_OPENGL;
#');


@internal = (Doc => 'internal');

pp_def(
	'line_3x_3c',
	GenericTypes => [F,D],
	Pars => 'coords(tri=3,n); colors(tri,n);',
	Code => '
		glBegin(GL_LINE_STRIP);
		loop(n) %{
			glColor3f(
				$colors(tri => 0), 
				$colors(tri => 1),
				$colors(tri => 2)
			);
			glVertex3f(
				$coords(tri => 0), 
				$coords(tri => 1),
				$coords(tri => 2)
			);
		%}
		glEnd();
	',
	@internal
);

sub TRI {return "$_[0]$_[1](tri => 0),
		 $_[0]$_[1](tri => 1),
		 $_[0]$_[1](tri => 2)"}
sub COLOR{ "
			glColor3f(
				".  TRI('$colors',$_[0])
				."
			);
	" };
sub ADCOLOR{ "
			{
			GLfloat ad[4];
			".(join '',map {"ad[$_] = \$colors$_[0](tri => $_);"} 0..2).
			"ad[3] = 1.0;
			glMaterialfv(GL_FRONT_AND_BACK,GL_AMBIENT_AND_DIFFUSE,
				ad);
			}
	" };
sub VERTEX{ "
			glVertex3f(
				".  TRI('$coords',$_[0])
				."
			);
" };
sub NORMAL{ "
			glNormal3f(
				".  TRI('$norm',$_[0])
				."
			);
	" };
sub RPOS{ "
			glRasterPos3f(
				".  TRI('$coords',$_[0])
				."
			);
	" };

pp_def('gl_points',
	GenericTypes => [F,D],
	Pars => 'coords(tri=3); colors(tri);',
	Code => '
		glBegin(GL_POINTS);
		threadloop %{'.COLOR().VERTEX().'
		%}
		glEnd();
	',
	@internal
);

pp_def(
	'gl_lines',
	GenericTypes => [F,D],
	Pars => 'coords(tri,x);colors(tri,x);',
	Code => '
		glBegin(GL_LINES);
		loop(x) %{ '.COLOR().VERTEX().'
		%}
		glEnd();
	',
	@internal
);

pp_def(
	'gl_line_strip',
	GenericTypes => [F,D],
	Pars => 'coords(tri,x);colors(tri,x);',
	Code => '
		glBegin(GL_LINE_STRIP);
		loop(x) %{ '.COLOR().VERTEX().'
		%}
		glEnd();
	',
	@internal
);

pp_def(
 	'gl_texts',
 	GenericTypes => [F,D],
 	Pars => 'coords(tri,x); ',
	OtherPars => 'int base; SV *arr',
	Code => '
		SV *sv = $COMP(arr);
		AV *arr;
		if(!(SvROK(sv) && SvTYPE(SvRV(sv))==SVt_PVAV)) {
			barf("gl_texts requires an array ref");
		}
		arr = (AV *)SvRV(sv);

		glPushAttrib(GL_LIST_BIT);
		glListBase($COMP(base));

		loop(x) %{
                       STRLEN n_a;
			SV *elem = *(av_fetch(arr, x, 0));
			if(elem) {
                               char *str = SvPV(elem,n_a);
				'.RPOS().'
				glCallLists(strlen(str),GL_UNSIGNED_BYTE,
					(GLubyte*)str);
			}
		%}

		glPopAttrib();
	',
	@internal
);

for $m (
{Suf => '_mat',
 Func => \&ADCOLOR},
{Suf => '',
 Func => \&COLOR},
) {
for(
{Name => 'gl_triangles',
 NormalCode => ''},
{Name => 'gl_triangles_n',
 NormalCode => '
	tmp1[0] = $coordsb(tri => 0) - $coordsa(tri => 0);
	tmp1[1] = $coordsb(tri => 1) - $coordsa(tri => 1);
	tmp1[2] = $coordsb(tri => 2) - $coordsa(tri => 2);
	tmp2[0] = $coordsc(tri => 0) - $coordsa(tri => 0);
	tmp2[1] = $coordsc(tri => 1) - $coordsa(tri => 1);
	tmp2[2] = $coordsc(tri => 2) - $coordsa(tri => 2);
	glNormal3f(
		tmp1[1]*tmp2[2] - tmp2[1]*tmp1[2],
	      -(tmp1[0]*tmp2[2] - tmp2[0]*tmp1[2]),
		tmp1[0]*tmp2[1] - tmp2[0]*tmp1[1]
	);
 '
},
{Name => 'gl_triangles_wn',
 NormalArgs => 'norma(tri); normb(tri); normc(tri);',
 (map {("NormalCode".($_ eq 'A'?'':$_),NORMAL(lc $_))} (A..C)),
}) {
# This may be suboptimal but should still be fast enough..
# We only do triangles with this.
pp_def(
	$_->{Name}.$m->{Suf},
	GenericTypes => [F,D],
	Pars => 'coordsa(tri=3); coordsb(tri);
		 coordsc(tri);'.
		 $_->{NormalArgs}.
		 'colorsa(tri); colorsb(tri);
		 colorsc(tri);
		 ',
	Code => '
		float tmp1[3]; float tmp2[3];
		glBegin(GL_TRIANGLES);
		threadloop %{'.
			$_->{NormalCode}
			.&{$m->{Func}}("a").VERTEX("a").
			$_->{NormalCodeB}
	  		.&{$m->{Func}}("b").VERTEX("b").
			$_->{NormalCodeC}
			.&{$m->{Func}}("c").VERTEX("c").'
		%}
		glEnd();
		',
		@internal
);
}
}

pp_def('gl_arrows',
	Pars => 'coords(tri=3,n); int indsa(); int indsb();',
	OtherPars => 'float headlen; float width;',
	Code => '
		float hl = $COMP(headlen);
		float w = $COMP(width);
		float tmp2[3]; tmp2[0] = 0.000001; tmp2[1] = -0.0001; tmp2[2] = 1;
 		glBegin(GL_LINES);
		threadloop %{
			int a = $indsa();
			int b = $indsb();
			float tmp1[3]; 
			float norm[3];
			float norm2[3];
			float normlen,origlen,norm2len;
			tmp1[0] = $coords(tri => 0, n => a) -
				  $coords(tri => 0, n => b);
			tmp1[1] = $coords(tri => 1, n => a) -
				  $coords(tri => 1, n => b);
			tmp1[2] = $coords(tri => 2, n => a) -
				  $coords(tri => 2, n => b);
		
			norm[0] = tmp1[1]*tmp2[2] - tmp2[1]*tmp1[2];
			norm[1] = -(tmp1[0]*tmp2[2] - tmp2[0]*tmp1[2]);
			norm[2] = tmp1[0]*tmp2[1] - tmp2[0]*tmp1[1];

			norm2[0] = tmp1[1]*norm[2] - norm[1]*tmp1[2];
			norm2[1] = -(tmp1[0]*norm[2] - norm[0]*tmp1[2]);
			norm2[2] = tmp1[0]*norm[1] - norm[0]*tmp1[1];

			normlen = sqrt(norm[0] * norm[0] +
				norm[1] * norm[1] + norm[2] * norm[2]);
			norm2len = sqrt(norm2[0] * norm2[0] +
				norm2[1] * norm2[1] + norm2[2] * norm2[2]);
			origlen = sqrt(tmp1[0] * tmp1[0] +
				tmp1[1] * tmp1[1] + tmp1[2] * tmp1[2]);
			norm[0] *= w/normlen;
			norm[1] *= w/normlen;
			norm[2] *= w/normlen;
			norm2[0] *= w/norm2len;
			norm2[1] *= w/norm2len;
			norm2[2] *= w/norm2len;
			tmp1[0] /= origlen;
			tmp1[1] /= origlen;
			tmp1[2] /= origlen;
			glVertex3d( $coords(tri => 0, n => a) ,
				    $coords(tri => 1, n => a) ,
				    $coords(tri => 2, n => a) );
			glVertex3d( $coords(tri => 0, n => b) ,
				    $coords(tri => 1, n => b) ,
				    $coords(tri => 2, n => b) );
			if(w!=0) {
			glVertex3d( $coords(tri => 0, n => b) ,
				    $coords(tri => 1, n => b) ,
				    $coords(tri => 2, n => b) );
			glVertex3d( $coords(tri => 0, n => b) + hl*tmp1[0] + norm[0],
				    $coords(tri => 1, n => b) + hl*tmp1[1] + norm[1],
				    $coords(tri => 2, n => b) + hl*tmp1[2] + norm[2]);
			glVertex3d( $coords(tri => 0, n => b) ,
				    $coords(tri => 1, n => b) ,
				    $coords(tri => 2, n => b) );
			glVertex3d( $coords(tri => 0, n => b) + hl*tmp1[0] - norm[0],
				    $coords(tri => 1, n => b) + hl*tmp1[1] - norm[1],
				    $coords(tri => 2, n => b) + hl*tmp1[2] - norm[2]);
			glVertex3d( $coords(tri => 0, n => b) ,
				    $coords(tri => 1, n => b) ,
				    $coords(tri => 2, n => b) );
			glVertex3d( $coords(tri => 0, n => b) + hl*tmp1[0] + norm2[0],
				    $coords(tri => 1, n => b) + hl*tmp1[1] + norm2[1],
				    $coords(tri => 2, n => b) + hl*tmp1[2] + norm2[2]);
			glVertex3d( $coords(tri => 0, n => b) ,
				    $coords(tri => 1, n => b) ,
				    $coords(tri => 2, n => b) );
			glVertex3d( $coords(tri => 0, n => b) + hl*tmp1[0] - norm2[0],
				    $coords(tri => 1, n => b) + hl*tmp1[1] - norm2[1],
				    $coords(tri => 2, n => b) + hl*tmp1[2] - norm2[2]);
			}
		%}
		glEnd();
	',
	@internal
);

pp_done();