Ejemplo n.º 1
0
static void build_fog( struct tnl_program *p )
{
   struct ureg fog = register_output(p, VARYING_SLOT_FOGC);
   struct ureg input;

   if (p->state->fog_source_is_depth) {

      switch (p->state->fog_distance_mode) {
      case FDM_EYE_RADIAL: /* Z = sqrt(Xe*Xe + Ye*Ye + Ze*Ze) */
	input = get_eye_position(p);
	emit_op2(p, OPCODE_DP3, fog, WRITEMASK_X, input, input);
	emit_op1(p, OPCODE_RSQ, fog, WRITEMASK_X, fog);
	emit_op1(p, OPCODE_RCP, fog, WRITEMASK_X, fog);
	break;
      case FDM_EYE_PLANE: /* Z = Ze */
	input = get_eye_position_z(p);
	emit_op1(p, OPCODE_MOV, fog, WRITEMASK_X, input);
	break;
      case FDM_EYE_PLANE_ABS: /* Z = abs(Ze) */
	input = get_eye_position_z(p);
	emit_op1(p, OPCODE_ABS, fog, WRITEMASK_X, input);
	break;
      default: assert(0); break; /* can't happen */
      }

   }
   else {
      input = swizzle1(register_input(p, VERT_ATTRIB_FOG), X);
      emit_op1(p, OPCODE_ABS, fog, WRITEMASK_X, input);
   }

   emit_op1(p, OPCODE_MOV, fog, WRITEMASK_YZW, get_identity_param(p));
}
Ejemplo n.º 2
0
/* Seems like it could be tighter:
 */
static void build_pointsize( struct tnl_program *p )
{
   struct ureg eye = get_eye_position(p);
   struct ureg state_size = register_param1(p, STATE_POINT_SIZE);
   struct ureg state_attenuation = register_param1(p, STATE_POINT_ATTENUATION);
   struct ureg out = register_output(p, VERT_RESULT_PSIZ);
   struct ureg ut = get_temp(p);

   /* 1, Z, Z * Z, 1 */      
   emit_op1(p, OPCODE_MOV, ut, WRITEMASK_XW, swizzle1(get_identity_param(p), W));
   emit_op1(p, OPCODE_ABS, ut, WRITEMASK_YZ, swizzle1(eye, Z));
   emit_op2(p, OPCODE_MUL, ut, WRITEMASK_Z, ut, ut);


   /* p1 +  p2 * dist + p3 * dist * dist, 0 */
   emit_op2(p, OPCODE_DP3, ut, WRITEMASK_X, ut, state_attenuation);

   /* 1 / sqrt(factor) */
   emit_op1(p, OPCODE_RSQ, ut, WRITEMASK_X, ut ); 

   /* ut = pointSize / factor */
   emit_op2(p, OPCODE_MUL, ut, WRITEMASK_X, ut, state_size); 

   /* Clamp to min/max - state_size.[yz]
    */
   emit_op2(p, OPCODE_MAX, ut, WRITEMASK_X, ut, swizzle1(state_size, Y)); 
   emit_op2(p, OPCODE_MIN, out, 0, swizzle1(ut, X), swizzle1(state_size, Z)); 
   
   release_temp(p, ut);
}
static void build_pointsize( struct tnl_program *p )
{
   struct ureg eye = get_eye_position(p);
   struct ureg state_size = register_param1(p, STATE_POINT_SIZE);
   struct ureg state_attenuation = register_param1(p, STATE_POINT_ATTENUATION);
   struct ureg out = register_output(p, VERT_RESULT_PSIZ);
   struct ureg ut = get_temp(p);

   /* dist = |eyez| */
   emit_op1(p, OPCODE_ABS, ut, WRITEMASK_Y, swizzle1(eye, Z));
   /* p1 + dist * (p2 + dist * p3); */
   emit_op3(p, OPCODE_MAD, ut, WRITEMASK_X, swizzle1(ut, Y),
		swizzle1(state_attenuation, Z), swizzle1(state_attenuation, Y));
   emit_op3(p, OPCODE_MAD, ut, WRITEMASK_X, swizzle1(ut, Y),
		ut, swizzle1(state_attenuation, X));

   /* 1 / sqrt(factor) */
   emit_op1(p, OPCODE_RSQ, ut, WRITEMASK_X, ut );

#if 1
   /* out = pointSize / sqrt(factor) */
   emit_op2(p, OPCODE_MUL, out, WRITEMASK_X, ut, state_size);
#else
   /* not sure, might make sense to do clamping here,
      but it's not done in t_vb_points neither */
   emit_op2(p, OPCODE_MUL, ut, WRITEMASK_X, ut, state_size);
   emit_op2(p, OPCODE_MAX, ut, WRITEMASK_X, ut, swizzle1(state_size, Y));
   emit_op2(p, OPCODE_MIN, out, WRITEMASK_X, ut, swizzle1(state_size, Z));
#endif

   release_temp(p, ut);
}
Ejemplo n.º 4
0
static void build_fog( struct tnl_program *p )
{
   struct ureg fog = register_output(p, VERT_RESULT_FOGC);
   struct ureg input;
   GLuint useabs = p->state->fog_source_is_depth && p->state->fog_option &&
		   (p->state->fog_option != FOG_EXP2);

   if (p->state->fog_source_is_depth) {
      input = swizzle1(get_eye_position(p), Z);
   }
   else {
      input = swizzle1(register_input(p, VERT_ATTRIB_FOG), X);
   }

   if (p->state->fog_option &&
       p->state->tnl_do_vertex_fog) {
      struct ureg params = register_param2(p, STATE_INTERNAL,
					   STATE_FOG_PARAMS_OPTIMIZED);
      struct ureg tmp = get_temp(p);
      struct ureg id = get_identity_param(p);

      emit_op1(p, OPCODE_MOV, fog, 0, id);

      if (useabs) {
	 emit_op1(p, OPCODE_ABS, tmp, 0, input);
      }

      switch (p->state->fog_option) {
      case FOG_LINEAR: {
	 emit_op3(p, OPCODE_MAD, tmp, 0, useabs ? tmp : input,
			swizzle1(params,X), swizzle1(params,Y));
	 emit_op2(p, OPCODE_MAX, tmp, 0, tmp, swizzle1(id,X)); /* saturate */
	 emit_op2(p, OPCODE_MIN, fog, WRITEMASK_X, tmp, swizzle1(id,W));
	 break;
      }
      case FOG_EXP:
	 emit_op2(p, OPCODE_MUL, tmp, 0, useabs ? tmp : input,
			swizzle1(params,Z));
	 emit_op1(p, OPCODE_EX2, fog, WRITEMASK_X, ureg_negate(tmp));
	 break;
      case FOG_EXP2:
	 emit_op2(p, OPCODE_MUL, tmp, 0, input, swizzle1(params,W));
	 emit_op2(p, OPCODE_MUL, tmp, 0, tmp, tmp);
	 emit_op1(p, OPCODE_EX2, fog, WRITEMASK_X, ureg_negate(tmp));
	 break;
      }

      release_temp(p, tmp);
   }
   else {
      /* results = incoming fog coords (compute fog per-fragment later) 
       *
       * KW:  Is it really necessary to do anything in this case?
       */
      emit_op1(p, useabs ? OPCODE_ABS : OPCODE_MOV, fog, 0, input);
   }
}
static void build_fog( struct tnl_program *p )
{
   struct ureg fog = register_output(p, VERT_RESULT_FOGC);
   struct ureg input;

   if (p->state->fog_source_is_depth) {
      input = swizzle1(get_eye_position(p), Z);
   }
   else {
      input = swizzle1(register_input(p, VERT_ATTRIB_FOG), X);
   }

   if (p->state->fog_mode && p->state->tnl_do_vertex_fog) {
      struct ureg params = register_param2(p, STATE_INTERNAL,
					   STATE_FOG_PARAMS_OPTIMIZED);
      struct ureg tmp = get_temp(p);
      GLboolean useabs = (p->state->fog_mode != FOG_EXP2);

      if (useabs) {
	 emit_op1(p, OPCODE_ABS, tmp, 0, input);
      }

      switch (p->state->fog_mode) {
      case FOG_LINEAR: {
	 struct ureg id = get_identity_param(p);
	 emit_op3(p, OPCODE_MAD, tmp, 0, useabs ? tmp : input,
			swizzle1(params,X), swizzle1(params,Y));
	 emit_op2(p, OPCODE_MAX, tmp, 0, tmp, swizzle1(id,X)); /* saturate */
	 emit_op2(p, OPCODE_MIN, fog, WRITEMASK_X, tmp, swizzle1(id,W));
	 break;
      }
      case FOG_EXP:
	 emit_op2(p, OPCODE_MUL, tmp, 0, useabs ? tmp : input,
			swizzle1(params,Z));
	 emit_op1(p, OPCODE_EX2, fog, WRITEMASK_X, negate(tmp));
	 break;
      case FOG_EXP2:
	 emit_op2(p, OPCODE_MUL, tmp, 0, input, swizzle1(params,W));
	 emit_op2(p, OPCODE_MUL, tmp, 0, tmp, tmp);
	 emit_op1(p, OPCODE_EX2, fog, WRITEMASK_X, negate(tmp));
	 break;
      }

      release_temp(p, tmp);
   }
   else {
      /* results = incoming fog coords (compute fog per-fragment later) 
       *
       * KW:  Is it really necessary to do anything in this case?
       * BP: Yes, we always need to compute the absolute value, unless
       * we want to push that down into the fragment program...
       */
      GLboolean useabs = GL_TRUE;
      emit_op1(p, useabs ? OPCODE_ABS : OPCODE_MOV, fog, WRITEMASK_X, input);
   }
}
Ejemplo n.º 6
0
static struct ureg get_eye_position_normalized( struct tnl_program *p )
{
   if (is_undef(p->eye_position_normalized)) {
      struct ureg eye = get_eye_position(p);
      p->eye_position_normalized = reserve_temp(p);
      emit_normalize_vec3(p, p->eye_position_normalized, eye);
   }

   return p->eye_position_normalized;
}
Ejemplo n.º 7
0
static void build_texture_transform( struct tnl_program *p )
{
   GLuint i, j;

   for (i = 0; i < MAX_TEXTURE_COORD_UNITS; i++) {

      if (!(p->state->fragprog_inputs_read & FRAG_BIT_TEX(i)))
	 continue;

      if (p->state->unit[i].texgen_enabled ||
	  p->state->unit[i].texmat_enabled) {

	 GLuint texmat_enabled = p->state->unit[i].texmat_enabled;
	 struct ureg out = register_output(p, VERT_RESULT_TEX0 + i);
	 struct ureg out_texgen = undef;

	 if (p->state->unit[i].texgen_enabled) {
	    GLuint copy_mask = 0;
	    GLuint sphere_mask = 0;
	    GLuint reflect_mask = 0;
	    GLuint normal_mask = 0;
	    GLuint modes[4];

	    if (texmat_enabled)
	       out_texgen = get_temp(p);
	    else
	       out_texgen = out;

	    modes[0] = p->state->unit[i].texgen_mode0;
	    modes[1] = p->state->unit[i].texgen_mode1;
	    modes[2] = p->state->unit[i].texgen_mode2;
	    modes[3] = p->state->unit[i].texgen_mode3;

	    for (j = 0; j < 4; j++) {
	       switch (modes[j]) {
	       case TXG_OBJ_LINEAR: {
		  struct ureg obj = register_input(p, VERT_ATTRIB_POS);
		  struct ureg plane =
		     register_param3(p, STATE_TEXGEN, i,
				     STATE_TEXGEN_OBJECT_S + j);

		  emit_op2(p, OPCODE_DP4, out_texgen, WRITEMASK_X << j,
			   obj, plane );
		  break;
	       }
	       case TXG_EYE_LINEAR: {
		  struct ureg eye = get_eye_position(p);
		  struct ureg plane =
		     register_param3(p, STATE_TEXGEN, i,
				     STATE_TEXGEN_EYE_S + j);

		  emit_op2(p, OPCODE_DP4, out_texgen, WRITEMASK_X << j,
			   eye, plane );
		  break;
	       }
	       case TXG_SPHERE_MAP:
		  sphere_mask |= WRITEMASK_X << j;
		  break;
	       case TXG_REFLECTION_MAP:
		  reflect_mask |= WRITEMASK_X << j;
		  break;
	       case TXG_NORMAL_MAP:
		  normal_mask |= WRITEMASK_X << j;
		  break;
	       case TXG_NONE:
		  copy_mask |= WRITEMASK_X << j;
	       }
	    }

	    if (sphere_mask) {
	       build_sphere_texgen(p, out_texgen, sphere_mask);
	    }

	    if (reflect_mask) {
	       build_reflect_texgen(p, out_texgen, reflect_mask);
	    }

	    if (normal_mask) {
	       struct ureg normal = get_transformed_normal(p);
	       emit_op1(p, OPCODE_MOV, out_texgen, normal_mask, normal );
	    }

	    if (copy_mask) {
	       struct ureg in = register_input(p, VERT_ATTRIB_TEX0+i);
	       emit_op1(p, OPCODE_MOV, out_texgen, copy_mask, in );
	    }
	 }

	 if (texmat_enabled) {
	    struct ureg texmat[4];
	    struct ureg in = (!is_undef(out_texgen) ?
			      out_texgen :
			      register_input(p, VERT_ATTRIB_TEX0+i));
	    if (p->mvp_with_dp4) {
	       register_matrix_param5( p, STATE_TEXTURE_MATRIX, i, 0, 3,
				       0, texmat );
	       emit_matrix_transform_vec4( p, out, texmat, in );
	    }
	    else {
	       register_matrix_param5( p, STATE_TEXTURE_MATRIX, i, 0, 3,
				       STATE_MATRIX_TRANSPOSE, texmat );
	       emit_transpose_matrix_transform_vec4( p, out, texmat, in );
	    }
	 }

	 release_temps(p);
      }
      else {
	 emit_passthrough(p, VERT_ATTRIB_TEX0+i, VERT_RESULT_TEX0+i);
      }
   }
}
Ejemplo n.º 8
0
/* Need to add some addtional parameters to allow lighting in object
 * space - STATE_SPOT_DIRECTION and STATE_HALF_VECTOR implicitly assume eye
 * space lighting.
 */
static void build_lighting( struct tnl_program *p )
{
   const GLboolean twoside = p->state->light_twoside;
   const GLboolean separate = p->state->separate_specular;
   GLuint nr_lights = 0, count = 0;
   struct ureg normal = get_transformed_normal(p);
   struct ureg lit = get_temp(p);
   struct ureg dots = get_temp(p);
   struct ureg _col0 = undef, _col1 = undef;
   struct ureg _bfc0 = undef, _bfc1 = undef;
   GLuint i;

   /*
    * NOTE:
    * dots.x = dot(normal, VPpli)
    * dots.y = dot(normal, halfAngle)
    * dots.z = back.shininess
    * dots.w = front.shininess
    */

   for (i = 0; i < MAX_LIGHTS; i++)
      if (p->state->unit[i].light_enabled)
	 nr_lights++;

   set_material_flags(p);

   {
      if (!p->state->material_shininess_is_zero) {
         struct ureg shininess = get_material(p, 0, STATE_SHININESS);
         emit_op1(p, OPCODE_MOV, dots, WRITEMASK_W, swizzle1(shininess,X));
         release_temp(p, shininess);
      }

      _col0 = make_temp(p, get_scenecolor(p, 0));
      if (separate)
	 _col1 = make_temp(p, get_identity_param(p));
      else
	 _col1 = _col0;
   }

   if (twoside) {
      if (!p->state->material_shininess_is_zero) {
         /* Note that we negate the back-face specular exponent here.
          * The negation will be un-done later in the back-face code below.
          */
         struct ureg shininess = get_material(p, 1, STATE_SHININESS);
         emit_op1(p, OPCODE_MOV, dots, WRITEMASK_Z,
                  negate(swizzle1(shininess,X)));
         release_temp(p, shininess);
      }

      _bfc0 = make_temp(p, get_scenecolor(p, 1));
      if (separate)
	 _bfc1 = make_temp(p, get_identity_param(p));
      else
	 _bfc1 = _bfc0;
   }

   /* If no lights, still need to emit the scenecolor.
    */
   {
      struct ureg res0 = register_output( p, VERT_RESULT_COL0 );
      emit_op1(p, OPCODE_MOV, res0, 0, _col0);
   }

   if (separate) {
      struct ureg res1 = register_output( p, VERT_RESULT_COL1 );
      emit_op1(p, OPCODE_MOV, res1, 0, _col1);
   }

   if (twoside) {
      struct ureg res0 = register_output( p, VERT_RESULT_BFC0 );
      emit_op1(p, OPCODE_MOV, res0, 0, _bfc0);
   }

   if (twoside && separate) {
      struct ureg res1 = register_output( p, VERT_RESULT_BFC1 );
      emit_op1(p, OPCODE_MOV, res1, 0, _bfc1);
   }

   if (nr_lights == 0) {
      release_temps(p);
      return;
   }

   for (i = 0; i < MAX_LIGHTS; i++) {
      if (p->state->unit[i].light_enabled) {
	 struct ureg half = undef;
	 struct ureg att = undef, VPpli = undef;

	 count++;

	 if (p->state->unit[i].light_eyepos3_is_zero) {
	    /* Can used precomputed constants in this case.
	     * Attenuation never applies to infinite lights.
	     */
	    VPpli = register_param3(p, STATE_INTERNAL,
				    STATE_LIGHT_POSITION_NORMALIZED, i);

            if (!p->state->material_shininess_is_zero) {
               if (p->state->light_local_viewer) {
                  struct ureg eye_hat = get_eye_position_normalized(p);
                  half = get_temp(p);
                  emit_op2(p, OPCODE_SUB, half, 0, VPpli, eye_hat);
                  emit_normalize_vec3(p, half, half);
               }
               else {
                  half = register_param3(p, STATE_INTERNAL,
                                         STATE_LIGHT_HALF_VECTOR, i);
               }
            }
	 }
	 else {
	    struct ureg Ppli = register_param3(p, STATE_INTERNAL,
					       STATE_LIGHT_POSITION, i);
	    struct ureg V = get_eye_position(p);
	    struct ureg dist = get_temp(p);

	    VPpli = get_temp(p);

	    /* Calculate VPpli vector
	     */
	    emit_op2(p, OPCODE_SUB, VPpli, 0, Ppli, V);

	    /* Normalize VPpli.  The dist value also used in
	     * attenuation below.
	     */
	    emit_op2(p, OPCODE_DP3, dist, 0, VPpli, VPpli);
	    emit_op1(p, OPCODE_RSQ, dist, 0, dist);
	    emit_op2(p, OPCODE_MUL, VPpli, 0, VPpli, dist);

	    /* Calculate attenuation:
	     */
	    if (!p->state->unit[i].light_spotcutoff_is_180 ||
		p->state->unit[i].light_attenuated) {
	       att = calculate_light_attenuation(p, i, VPpli, dist);
	    }

	    /* Calculate viewer direction, or use infinite viewer:
	     */
            if (!p->state->material_shininess_is_zero) {
               half = get_temp(p);

               if (p->state->light_local_viewer) {
                  struct ureg eye_hat = get_eye_position_normalized(p);
                  emit_op2(p, OPCODE_SUB, half, 0, VPpli, eye_hat);
               }
               else {
                  struct ureg z_dir = swizzle(get_identity_param(p),X,Y,W,Z);
                  emit_op2(p, OPCODE_ADD, half, 0, VPpli, z_dir);
               }

               emit_normalize_vec3(p, half, half);
            }

	    release_temp(p, dist);
	 }

	 /* Calculate dot products:
	  */
         if (p->state->material_shininess_is_zero) {
            emit_op2(p, OPCODE_DP3, dots, 0, normal, VPpli);
         }
         else {
            emit_op2(p, OPCODE_DP3, dots, WRITEMASK_X, normal, VPpli);
            emit_op2(p, OPCODE_DP3, dots, WRITEMASK_Y, normal, half);
         }

	 /* Front face lighting:
	  */
	 {
	    struct ureg ambient = get_lightprod(p, i, 0, STATE_AMBIENT);
	    struct ureg diffuse = get_lightprod(p, i, 0, STATE_DIFFUSE);
	    struct ureg specular = get_lightprod(p, i, 0, STATE_SPECULAR);
	    struct ureg res0, res1;
	    GLuint mask0, mask1;

	    if (count == nr_lights) {
	       if (separate) {
		  mask0 = WRITEMASK_XYZ;
		  mask1 = WRITEMASK_XYZ;
		  res0 = register_output( p, VERT_RESULT_COL0 );
		  res1 = register_output( p, VERT_RESULT_COL1 );
	       }
	       else {
		  mask0 = 0;
		  mask1 = WRITEMASK_XYZ;
		  res0 = _col0;
		  res1 = register_output( p, VERT_RESULT_COL0 );
	       }
	    }
            else {
	       mask0 = 0;
	       mask1 = 0;
	       res0 = _col0;
	       res1 = _col1;
	    }

	    if (!is_undef(att)) {
               /* light is attenuated by distance */
               emit_op1(p, OPCODE_LIT, lit, 0, dots);
               emit_op2(p, OPCODE_MUL, lit, 0, lit, att);
               emit_op3(p, OPCODE_MAD, _col0, 0, swizzle1(lit,X), ambient, _col0);
            }
            else if (!p->state->material_shininess_is_zero) {
               /* there's a non-zero specular term */
               emit_op1(p, OPCODE_LIT, lit, 0, dots);
               emit_op2(p, OPCODE_ADD, _col0, 0, ambient, _col0);
            }
            else {
               /* no attenutation, no specular */
               emit_degenerate_lit(p, lit, dots);
               emit_op2(p, OPCODE_ADD, _col0, 0, ambient, _col0);
            }

	    emit_op3(p, OPCODE_MAD, res0, mask0, swizzle1(lit,Y), diffuse, _col0);
	    emit_op3(p, OPCODE_MAD, res1, mask1, swizzle1(lit,Z), specular, _col1);

	    release_temp(p, ambient);
	    release_temp(p, diffuse);
	    release_temp(p, specular);
	 }

	 /* Back face lighting:
	  */
	 if (twoside) {
	    struct ureg ambient = get_lightprod(p, i, 1, STATE_AMBIENT);
	    struct ureg diffuse = get_lightprod(p, i, 1, STATE_DIFFUSE);
	    struct ureg specular = get_lightprod(p, i, 1, STATE_SPECULAR);
	    struct ureg res0, res1;
	    GLuint mask0, mask1;

	    if (count == nr_lights) {
	       if (separate) {
		  mask0 = WRITEMASK_XYZ;
		  mask1 = WRITEMASK_XYZ;
		  res0 = register_output( p, VERT_RESULT_BFC0 );
		  res1 = register_output( p, VERT_RESULT_BFC1 );
	       }
	       else {
		  mask0 = 0;
		  mask1 = WRITEMASK_XYZ;
		  res0 = _bfc0;
		  res1 = register_output( p, VERT_RESULT_BFC0 );
	       }
	    }
            else {
	       res0 = _bfc0;
	       res1 = _bfc1;
	       mask0 = 0;
	       mask1 = 0;
	    }

            /* For the back face we need to negate the X and Y component
             * dot products.  dots.Z has the negated back-face specular
             * exponent.  We swizzle that into the W position.  This
             * negation makes the back-face specular term positive again.
             */
            dots = negate(swizzle(dots,X,Y,W,Z));

	    if (!is_undef(att)) {
               emit_op1(p, OPCODE_LIT, lit, 0, dots);
	       emit_op2(p, OPCODE_MUL, lit, 0, lit, att);
               emit_op3(p, OPCODE_MAD, _bfc0, 0, swizzle1(lit,X), ambient, _bfc0);
            }
            else if (!p->state->material_shininess_is_zero) {
               emit_op1(p, OPCODE_LIT, lit, 0, dots);
               emit_op2(p, OPCODE_ADD, _bfc0, 0, ambient, _bfc0); /**/
            }
            else {
               emit_degenerate_lit(p, lit, dots);
               emit_op2(p, OPCODE_ADD, _bfc0, 0, ambient, _bfc0);
            }

	    emit_op3(p, OPCODE_MAD, res0, mask0, swizzle1(lit,Y), diffuse, _bfc0);
	    emit_op3(p, OPCODE_MAD, res1, mask1, swizzle1(lit,Z), specular, _bfc1);
            /* restore dots to its original state for subsequent lights
             * by negating and swizzling again.
             */
            dots = negate(swizzle(dots,X,Y,W,Z));

	    release_temp(p, ambient);
	    release_temp(p, diffuse);
	    release_temp(p, specular);
	 }

	 release_temp(p, half);
	 release_temp(p, VPpli);
	 release_temp(p, att);
      }
   }

   release_temps( p );
}
Ejemplo n.º 9
0
/* Need to add some addtional parameters to allow lighting in object
 * space - STATE_SPOT_DIRECTION and STATE_HALF_VECTOR implicitly assume eye
 * space lighting.
 */
static void build_lighting( struct tnl_program *p )
{
   const GLboolean twoside = p->state->light_twoside;
   const GLboolean separate = p->state->separate_specular;
   GLuint nr_lights = 0, count = 0;
   struct ureg normal = get_eye_normal(p);
   struct ureg lit = get_temp(p);
   struct ureg dots = get_temp(p);
   struct ureg _col0 = undef, _col1 = undef;
   struct ureg _bfc0 = undef, _bfc1 = undef;
   GLuint i;

   for (i = 0; i < MAX_LIGHTS; i++) 
      if (p->state->unit[i].light_enabled)
	 nr_lights++;
   
   set_material_flags(p);

   {
      struct ureg shininess = get_material(p, 0, STATE_SHININESS);
      emit_op1(p, OPCODE_MOV, dots,  WRITEMASK_W, swizzle1(shininess,X));
      release_temp(p, shininess);

      _col0 = make_temp(p, get_scenecolor(p, 0));
      if (separate)
	 _col1 = make_temp(p, get_identity_param(p));
      else
	 _col1 = _col0;

   }

   if (twoside) {
      struct ureg shininess = get_material(p, 1, STATE_SHININESS);
      emit_op1(p, OPCODE_MOV, dots, WRITEMASK_Z, 
	       ureg_negate(swizzle1(shininess,X)));
      release_temp(p, shininess);

      _bfc0 = make_temp(p, get_scenecolor(p, 1));
      if (separate)
	 _bfc1 = make_temp(p, get_identity_param(p));
      else
	 _bfc1 = _bfc0;
   }


   /* If no lights, still need to emit the scenecolor.
    */
   /* KW: changed to do this always - v1.17 "Fix lighting alpha result"? 
    */
   if (p->state->fragprog_inputs_read & FRAG_BIT_COL0)
   {
      struct ureg res0 = register_output( p, VERT_RESULT_COL0 );
      emit_op1(p, OPCODE_MOV, res0, 0, _col0);

      if (twoside) {
	 struct ureg res0 = register_output( p, VERT_RESULT_BFC0 );
	 emit_op1(p, OPCODE_MOV, res0, 0, _bfc0);
      }
   }

   if (separate && (p->state->fragprog_inputs_read & FRAG_BIT_COL1)) {

      struct ureg res1 = register_output( p, VERT_RESULT_COL1 );
      emit_op1(p, OPCODE_MOV, res1, 0, _col1);
      
      if (twoside) {
	 struct ureg res1 = register_output( p, VERT_RESULT_BFC1 );
	 emit_op1(p, OPCODE_MOV, res1, 0, _bfc1);
      }
   }
      
   if (nr_lights == 0) {
      release_temps(p);
      return;
   }


   for (i = 0; i < MAX_LIGHTS; i++) {
      if (p->state->unit[i].light_enabled) {
	 struct ureg half = undef;
	 struct ureg att = undef, VPpli = undef;
	  
	 count++;

	 if (p->state->unit[i].light_eyepos3_is_zero) {
	    /* Can used precomputed constants in this case.
	     * Attenuation never applies to infinite lights.
	     */
	    VPpli = register_param3(p, STATE_LIGHT, i, 
				    STATE_POSITION_NORMALIZED); 
            if (p->state->light_local_viewer) {
                struct ureg eye_hat = get_eye_position_normalized(p);
                half = get_temp(p);
                emit_op2(p, OPCODE_SUB, half, 0, VPpli, eye_hat);
                emit_normalize_vec3(p, half, half);
            } else {
                half = register_param3(p, STATE_LIGHT, i, STATE_HALF_VECTOR);
            }
	 } 
	 else {
	    struct ureg Ppli = register_param3(p, STATE_LIGHT, i, 
					       STATE_POSITION); 
	    struct ureg V = get_eye_position(p);
	    struct ureg dist = get_temp(p);

	    VPpli = get_temp(p); 
	    half = get_temp(p);
 
	    /* Calulate VPpli vector
	     */
	    emit_op2(p, OPCODE_SUB, VPpli, 0, Ppli, V); 

	    /* Normalize VPpli.  The dist value also used in
	     * attenuation below.
	     */
	    emit_op2(p, OPCODE_DP3, dist, 0, VPpli, VPpli);
	    emit_op1(p, OPCODE_RSQ, dist, 0, dist);
	    emit_op2(p, OPCODE_MUL, VPpli, 0, VPpli, dist);


	    /* Calculate  attenuation:
	     */ 
	    if (!p->state->unit[i].light_spotcutoff_is_180 ||
		p->state->unit[i].light_attenuated) {
	       att = calculate_light_attenuation(p, i, VPpli, dist);
	    }
	 
      
	    /* Calculate viewer direction, or use infinite viewer:
	     */
	    if (p->state->light_local_viewer) {
	       struct ureg eye_hat = get_eye_position_normalized(p);
	       emit_op2(p, OPCODE_SUB, half, 0, VPpli, eye_hat);
	    }
	    else {
	       struct ureg z_dir = swizzle(get_identity_param(p),X,Y,W,Z); 
	       emit_op2(p, OPCODE_ADD, half, 0, VPpli, z_dir);
	    }

	    emit_normalize_vec3(p, half, half);

	    release_temp(p, dist);
	 }

	 /* Calculate dot products:
	  */
	 emit_op2(p, OPCODE_DP3, dots, WRITEMASK_X, normal, VPpli);
	 emit_op2(p, OPCODE_DP3, dots, WRITEMASK_Y, normal, half);

	
	 /* Front face lighting:
	  */
	 {
	    struct ureg ambient = get_lightprod(p, i, 0, STATE_AMBIENT);
	    struct ureg diffuse = get_lightprod(p, i, 0, STATE_DIFFUSE);
	    struct ureg specular = get_lightprod(p, i, 0, STATE_SPECULAR);
	    struct ureg res0, res1;
	    GLuint mask0, mask1;

	    emit_op1(p, OPCODE_LIT, lit, 0, dots);
   
	    if (!is_undef(att)) 
	       emit_op2(p, OPCODE_MUL, lit, 0, lit, att);


	    mask0 = 0;
	    mask1 = 0;
	    res0 = _col0;
	    res1 = _col1;
	    
	    if (count == nr_lights) {
	       if (separate) {
		  mask0 = WRITEMASK_XYZ;
		  mask1 = WRITEMASK_XYZ;

		  if (p->state->fragprog_inputs_read & FRAG_BIT_COL0)
		     res0 = register_output( p, VERT_RESULT_COL0 );

		  if (p->state->fragprog_inputs_read & FRAG_BIT_COL1)
		     res1 = register_output( p, VERT_RESULT_COL1 );
	       }
	       else {
		  mask1 = WRITEMASK_XYZ;

		  if (p->state->fragprog_inputs_read & FRAG_BIT_COL0)
		     res1 = register_output( p, VERT_RESULT_COL0 );
	       }
	    } 

	    emit_op3(p, OPCODE_MAD, _col0, 0, swizzle1(lit,X), ambient, _col0);
	    emit_op3(p, OPCODE_MAD, res0, mask0, swizzle1(lit,Y), diffuse, _col0);
	    emit_op3(p, OPCODE_MAD, res1, mask1, swizzle1(lit,Z), specular, _col1);
      
	    release_temp(p, ambient);
	    release_temp(p, diffuse);
	    release_temp(p, specular);
	 }

	 /* Back face lighting:
	  */
	 if (twoside) {
	    struct ureg ambient = get_lightprod(p, i, 1, STATE_AMBIENT);
	    struct ureg diffuse = get_lightprod(p, i, 1, STATE_DIFFUSE);
	    struct ureg specular = get_lightprod(p, i, 1, STATE_SPECULAR);
	    struct ureg res0, res1;
	    GLuint mask0, mask1;
	       
	    emit_op1(p, OPCODE_LIT, lit, 0, ureg_negate(swizzle(dots,X,Y,W,Z)));

	    if (!is_undef(att)) 
	       emit_op2(p, OPCODE_MUL, lit, 0, lit, att);

	    mask0 = 0;
	    mask1 = 0;
	    res0 = _bfc0;
	    res1 = _bfc1;

	    if (count == nr_lights) {
	       if (separate) {
		  mask0 = WRITEMASK_XYZ;
		  mask1 = WRITEMASK_XYZ;
		  if (p->state->fragprog_inputs_read & FRAG_BIT_COL0)
		     res0 = register_output( p, VERT_RESULT_BFC0 );

		  if (p->state->fragprog_inputs_read & FRAG_BIT_COL1)
		     res1 = register_output( p, VERT_RESULT_BFC1 );
	       }
	       else {
		  mask1 = WRITEMASK_XYZ;

		  if (p->state->fragprog_inputs_read & FRAG_BIT_COL0)
		     res1 = register_output( p, VERT_RESULT_BFC0 );
	       }
	    }

	    emit_op3(p, OPCODE_MAD, _bfc0, 0, swizzle1(lit,X), ambient, _bfc0);
	    emit_op3(p, OPCODE_MAD, res0, mask0, swizzle1(lit,Y), diffuse, _bfc0);
	    emit_op3(p, OPCODE_MAD, res1, mask1, swizzle1(lit,Z), specular, _bfc1);

	    release_temp(p, ambient);
	    release_temp(p, diffuse);
	    release_temp(p, specular);
	 }

	 release_temp(p, half);
	 release_temp(p, VPpli);
	 release_temp(p, att);
      }
   }

   release_temps( p );
}