Index: graf3d/gl/src/TGLParametric.cxx
===================================================================
--- graf3d/gl/src/TGLParametric.cxx	(revision 42013)
+++ graf3d/gl/src/TGLParametric.cxx	(working copy)
@@ -114,7 +114,8 @@
                     fURange(uMin, uMax),
                     fVRange(vMin, vMax),
                     fConstrained(kFALSE),
-                    fModified(kFALSE)
+  fModified(kFALSE),
+  GetColor(0)
 {
    //Surface is defined by three strings.
    //ROOT does not use exceptions in ctors,
@@ -163,7 +164,7 @@
                     fURange(uMin, uMax),
                     fVRange(vMin, vMax),
                     fConstrained(kFALSE),
-                    fModified(kFALSE)
+                    fModified(kFALSE),  GetColor(0)
 {
    //Surface defined by user's function (see ParametricEquation_t declaration in TGLParametricEquation.h)
    if (!fEquation) {
@@ -172,6 +173,23 @@
    }
 }
 
+TGLParametricEquation::TGLParametricEquation(const TString &name, ParametricEquation_t equation,
+					     void(*ColorFunc)(Double_t &color,Double_t u, Double_t v),
+					     Double_t uMin, Double_t uMax, Double_t vMin, Double_t vMax)
+  : TNamed(name, name),
+    fEquation(equation),
+    fURange(uMin, uMax),
+    fVRange(vMin, vMax),
+    fConstrained(kFALSE),
+    fModified(kFALSE),  GetColor(ColorFunc)
+{
+   //Surface defined by user's function (see ParametricEquation_t declaration in TGLParametricEquation.h)
+   if (!fEquation) {
+      Error("TGLParametricEquation", "Function ptr is null");
+      MakeZombie();
+   }
+}
+
 //______________________________________________________________________________
 Rgl::Range_t TGLParametricEquation::GetURange()const
 {
@@ -273,13 +291,14 @@
                         fMeshSize(90),
                         fShowMesh(kFALSE),
                         fColorScheme(4),
-                        fEquation(eq)
+  fEquation(eq)
 {
    //Constructor.
    InitGeometry();
    InitColors();
 }
 
+
 //______________________________________________________________________________
 Bool_t TGLParametricPlot::InitGeometry()
 {
@@ -593,15 +612,48 @@
    if (fColorScheme == -1)
       return;
 
-   const Rgl::Range_t uRange(fEquation->GetURange());
+   if(!fEquation->GetColor){
+     const Rgl::Range_t uRange(fEquation->GetURange());
 
-   const Float_t dU = Float_t((uRange.second - uRange.first) / (fMeshSize - 1));
-   Float_t u = Float_t(uRange.first);
-
-   for (Int_t i = 0; i < fMeshSize; ++i) {
-      for (Int_t j = 0; j < fMeshSize; ++j)
+     const Float_t dU = Float_t((uRange.second - uRange.first) / (fMeshSize - 1));
+     Float_t u = Float_t(uRange.first);
+     
+     for (Int_t i = 0; i < fMeshSize; ++i) {
+       for (Int_t j = 0; j < fMeshSize; ++j)
          Rgl::GetColor(u, uRange.first, uRange.second, fColorScheme, fMesh[i][j].fRGBA);
-      u += dU;
+       u += dU;
+     }
+   } else {
+     const Rgl::Range_t uRange(fEquation->GetURange());
+     const Rgl::Range_t vRange(fEquation->GetVRange());
+     
+     const Double_t dU = (uRange.second - uRange.first) / (fMeshSize - 1);
+     const Double_t dV = (vRange.second - vRange.first) / (fMeshSize - 1);
+     Double_t u = uRange.first;
+     Double_t min,max,col;
+     fEquation->GetColor(min, uRange.first, vRange.first);
+     max=min;
+     using namespace TMath;
+     for (Int_t i = 0; i < fMeshSize; ++i) {
+       Double_t v = vRange.first;
+       for (Int_t j = 0; j < fMeshSize; ++j) {
+	 fEquation->GetColor(col,u,v);
+	 if(col>max) max=col;
+	 if(col<min) min=col;
+	 v += dV;
+       }
+       u += dU;
+     }
+     u = uRange.first;
+     for (Int_t i = 0; i < fMeshSize; ++i) {
+       Double_t v = vRange.first;
+       for (Int_t j = 0; j < fMeshSize; ++j) {
+	 fEquation->GetColor(col,u,v);
+	 Rgl::GetColor(col, min,max, fColorScheme, fMesh[i][j].fRGBA);
+	 v += dV;
+       }
+       u += dU;
+     }
    }
 }