jvcllaz: Fix compilation with Laz 2.0.x

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@8163 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/jvcllaz/run/JvCore/jvjvclutils.pas

@@ -904,6 +904,46 @@ begin
   Result := Application.Handle;
 end;
 
+{$IF LCL_FullVersion < 2010000}
+// THESE ROUTINES ARE BORROWED FROM LAZARUS v2.1+ GRAPHUTILS
+
+{ Assumes R, G, B to be in range 0..255. Calculates H, S, V in range 0..1
+  From: http://axonflux.com/handy-rgb-to-hsl-and-rgb-to-hsv-color-model-c }
+procedure RGBToHSV(R, G, B: Integer; out H, S, V: Double);
+var
+  rr, gg, bb: Double;
+  cmax, cmin, delta: Double;
+begin
+  rr := R / 255;
+  gg := G / 255;
+  bb := B / 255;
+  cmax := MaxValue([rr, gg, bb]);
+  cmin := MinValue([rr, gg, bb]);
+  delta := cmax - cmin;
+  if delta = 0 then
+  begin
+    H := 0;
+    S := 0;
+  end else
+  begin
+    if cmax = rr then
+      H := (gg - bb) / delta + IfThen(gg < bb, 6, 0)
+    else if cmax = gg then
+      H := (bb - rr) / delta + 2
+    else if (cmax = bb) then
+      H := (rr -gg) / delta + 4;
+    H := H / 6;
+    S := delta / cmax;
+  end;
+  V := cmax;
+end;
+
+procedure ColorToHSV(c: TColor; out H, S, V: Double);
+begin
+  RGBToHSV(GetRValue(c), GetGValue(c), GetBValue(c), H, S, V);
+end;
+{$IFEND}
+
 (***************** NOT CONVERTED ***
 type
   TWaitCursor = class(TInterfacedObject, IInterface)