Vertex Shaders - Praise for OpenGL ES 30 Programming Guide - page 221

Example 8-9 OpenGL ES 1.1 Fixed-Function Vertex Pipeline (continued)

else
{
f = ( p_eye.z * fog_density );
f = exp( -( f * f ) );
}
f = clamp ( f, c_zero, c_one) ;
return f;
}

vec4 do_lighting( )
{
vec4 vtx_color;
int i, j ;

vtx_color = material_state.emissive_color +
( mat_ambient_color * ambient_scene_color );
j = int( c_zero );
for ( i=int( c_zero ); i<8; i++ )
{
if ( j >= num_lights )
break;

if ( light_enable_state[i] )
{
j++;
vtx_color += lighting_equation(i);
}
}

vtx_color.a = mat_diffuse_color.a;
return vtx_color;
}

void main( void )
{
int i, j;

// do we need to transform P
if ( xform_eye_p )
p_eye = modelview_matrix * a_position;

if ( enable_lighting )
{
n = inv_transpose_modelview_matrix * a_normal;
if ( rescale_normal )
n = rescale_normal_factor * n;

(continues)