RGBA Plate::EvalColor(ShadeContext& sc) {
BMM_Color_64 c;
IPoint2 s;
int id = sc.NodeID();
PlateMap *pmap = FindMap(id);
if (gbufID) sc.SetGBufferID(gbufID);
if (pmap) {
s = sc.ScreenCoord();
int w = pmap->bm->Width();
int h = pmap->bm->Height();
Point3 view = sc.OrigView();
Point3 v2 = sc.V();
Point3 p = sc.P();
Point3 dV,dvf;
Point3 N0 = sc.OrigNormal();
Point3 vf = RefractVector(sc, N0, view, sc.GetIOR());
RenderGlobalContext *gc = sc.globContext;
if (gc==NULL) return blackrgba;
// total deflection due to refraction
dV = view-v2;
// deflection due to flat refracton (no bumps)
dvf = view-vf;
dV = refrAmt*(dV-dvf) + thick*dvf;
// compute screen deflection: This is really a cheat, and the
// scale factor is arbitrary. Infact it depends on the distance
// between to the point on the glass plate and to the point being
// seen behind it, which we don't know.
// these should be multiplied by the factor (Zbehind-Zcur)/Zcur
// This assumes that the factor is .1
float dsx,dsy;
if (gc->projType==0) {
// perspective
dsx = dV.x*0.1f*gc->xscale;
dsy = dV.y*0.1f*gc->yscale;
}
else {
// parallel projection
dsx = -dV.x*gc->xscale*10.0f;
dsy = -dV.y*gc->yscale*10.0f;
}
if (gc->fieldRender) dsy *= 2.0f;
int x = s.x - (pmap->org.x+gc->devWidth/2);
int y = s.y - (pmap->org.y+gc->devHeight/2);
if (applyBlur) {
float du = 1.0f/float(w);
float dv = 1.0f/float(h);
float u = (float(x)+dsx)*du;
float v = (float(y)+dsy)*dv;
if (u<0.0f||u>1.0f||v<0.0f||v>1.0f) {
if (useEnvMap) {
return sc.EvalGlobalEnvironMap(view-dvf);
}
else
return blackrgba;
}
else
pmap->bm->GetFiltered(u,v, du*blur, dv*blur,&c);
}
else {
int ix = x + int(dsx);
int iy = y + int(dsy);
if (ix<0||ix>=w||iy<0||iy>=h) {
if (useEnvMap)
return sc.EvalGlobalEnvironMap(view-dvf);
else
return blackrgba;
}
else
pmap->bm->GetLinearPixels(ix,iy,1,&c);
}
return c;
}
else
return blackrgba;
}
