示例#1
0
void
_swrast_add_spec_terms_line( GLcontext *ctx,
                             const SWvertex *v0,
                             const SWvertex *v1 )
{
   SWvertex *ncv0 = (SWvertex *)v0;
   SWvertex *ncv1 = (SWvertex *)v1;
   GLchan c[2][4];
   COPY_CHAN4( c[0], ncv0->color );
   COPY_CHAN4( c[1], ncv1->color );
   ACC_3V( ncv0->color, ncv0->specular );
   ACC_3V( ncv1->color, ncv1->specular );
   SWRAST_CONTEXT(ctx)->SpecLine( ctx, ncv0, ncv1 );
   COPY_CHAN4( ncv0->color, c[0] );
   COPY_CHAN4( ncv1->color, c[1] );
}
示例#2
0
void _swrast_add_spec_terms_point( GLcontext *ctx,
				   const SWvertex *v0 )
{
   SWvertex *ncv0 = (SWvertex *)v0;
   GLchan c[1][4];
   COPY_CHAN4( c[0], ncv0->color );
   ACC_3V( ncv0->color, ncv0->specular );
   SWRAST_CONTEXT(ctx)->SpecPoint( ctx, ncv0 );
   COPY_CHAN4( ncv0->color, c[0] );
}
/**
 * Compute lighting for the raster position.  RGB modes computed.
 * \param ctx the context
 * \param vertex vertex location
 * \param normal normal vector
 * \param Rcolor returned color
 * \param Rspec returned specular color (if separate specular enabled)
 */
static void
shade_rastpos(struct gl_context *ctx,
              const GLfloat vertex[4],
              const GLfloat normal[3],
              GLfloat Rcolor[4],
              GLfloat Rspec[4])
{
   /*const*/ GLfloat (*base)[3] = ctx->Light._BaseColor;
   GLbitfield mask;
   GLfloat diffuseColor[4], specularColor[4];  /* for RGB mode only */

   COPY_3V(diffuseColor, base[0]);
   diffuseColor[3] = CLAMP(
      ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3], 0.0F, 1.0F );
   ASSIGN_4V(specularColor, 0.0, 0.0, 0.0, 1.0);

   mask = ctx->Light._EnabledLights;
   while (mask) {
      const int i = u_bit_scan(&mask);
      struct gl_light *light = &ctx->Light.Light[i];
      GLfloat attenuation = 1.0;
      GLfloat VP[3]; /* vector from vertex to light pos */
      GLfloat n_dot_VP;
      GLfloat diffuseContrib[3], specularContrib[3];

      if (!(light->_Flags & LIGHT_POSITIONAL)) {
         /* light at infinity */
	 COPY_3V(VP, light->_VP_inf_norm);
	 attenuation = light->_VP_inf_spot_attenuation;
      }
      else {
         /* local/positional light */
	 GLfloat d;

         /* VP = vector from vertex pos to light[i].pos */
	 SUB_3V(VP, light->_Position, vertex);
         /* d = length(VP) */
	 d = (GLfloat) LEN_3FV( VP );
	 if (d > 1.0e-6F) {
            /* normalize VP */
	    GLfloat invd = 1.0F / d;
	    SELF_SCALE_SCALAR_3V(VP, invd);
	 }

         /* atti */
	 attenuation = 1.0F / (light->ConstantAttenuation + d *
			       (light->LinearAttenuation + d *
				light->QuadraticAttenuation));

	 if (light->_Flags & LIGHT_SPOT) {
	    GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection);

	    if (PV_dot_dir<light->_CosCutoff) {
	       continue;
	    }
	    else {
               GLfloat spot = powf(PV_dot_dir, light->SpotExponent);
	       attenuation *= spot;
	    }
	 }
      }

      if (attenuation < 1e-3F)
	 continue;

      n_dot_VP = DOT3( normal, VP );

      if (n_dot_VP < 0.0F) {
	 ACC_SCALE_SCALAR_3V(diffuseColor, attenuation, light->_MatAmbient[0]);
	 continue;
      }

      /* Ambient + diffuse */
      COPY_3V(diffuseContrib, light->_MatAmbient[0]);
      ACC_SCALE_SCALAR_3V(diffuseContrib, n_dot_VP, light->_MatDiffuse[0]);

      /* Specular */
      {
         const GLfloat *h;
         GLfloat n_dot_h;

         ASSIGN_3V(specularContrib, 0.0, 0.0, 0.0);

	 if (ctx->Light.Model.LocalViewer) {
	    GLfloat v[3];
	    COPY_3V(v, vertex);
	    NORMALIZE_3FV(v);
	    SUB_3V(VP, VP, v);
            NORMALIZE_3FV(VP);
	    h = VP;
	 }
	 else if (light->_Flags & LIGHT_POSITIONAL) {
	    ACC_3V(VP, ctx->_EyeZDir);
            NORMALIZE_3FV(VP);
	    h = VP;
	 }
         else {
	    h = light->_h_inf_norm;
	 }

	 n_dot_h = DOT3(normal, h);

	 if (n_dot_h > 0.0F) {
	    GLfloat shine;
	    GLfloat spec_coef;

	    shine = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_SHININESS][0];
	    spec_coef = powf(n_dot_h, shine);

	    if (spec_coef > 1.0e-10F) {
               if (ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR) {
                  ACC_SCALE_SCALAR_3V( specularContrib, spec_coef,
                                       light->_MatSpecular[0]);
               }
               else {
                  ACC_SCALE_SCALAR_3V( diffuseContrib, spec_coef,
                                       light->_MatSpecular[0]);
               }
	    }
	 }
      }

      ACC_SCALE_SCALAR_3V( diffuseColor, attenuation, diffuseContrib );
      ACC_SCALE_SCALAR_3V( specularColor, attenuation, specularContrib );
   }

   Rcolor[0] = CLAMP(diffuseColor[0], 0.0F, 1.0F);
   Rcolor[1] = CLAMP(diffuseColor[1], 0.0F, 1.0F);
   Rcolor[2] = CLAMP(diffuseColor[2], 0.0F, 1.0F);
   Rcolor[3] = CLAMP(diffuseColor[3], 0.0F, 1.0F);
   Rspec[0] = CLAMP(specularColor[0], 0.0F, 1.0F);
   Rspec[1] = CLAMP(specularColor[1], 0.0F, 1.0F);
   Rspec[2] = CLAMP(specularColor[2], 0.0F, 1.0F);
   Rspec[3] = CLAMP(specularColor[3], 0.0F, 1.0F);
}