Erase with wx ok . (#2141)

Co-authored-by: Giloo <gildas@localhost>

Author: GillesDuvert

src/gdlwxstream.cpp

@@ -15,6 +15,8 @@
  *                                                                         *
  ***************************************************************************/
 
+#include <wx-3.0/wx/graphics.h>
+
 #include "includefirst.hpp"
 
 #ifdef HAVE_LIBWXWIDGETS
@@ -192,26 +194,41 @@ unsigned long GDLWXStream::GetWindowDepth() {
   return wxDisplayDepth();
 }
 
+// GD removed use of (wrong) plplot erase function
 void GDLWXStream::Clear() {
-      PLINT red,green,blue;
-      DByte r,g,b;
-      PLINT red0,green0,blue0;
-      
-      GraphicsDevice::GetCT()->Get(0,r,g,b);red=r;green=g;blue=b;
-      
-      red0=GraphicsDevice::GetDevice()->BackgroundR();
-      green0=GraphicsDevice::GetDevice()->BackgroundG();
-      blue0=GraphicsDevice::GetDevice()->BackgroundB();
-      plstream::scolbg(red0,green0,blue0); //overwrites col[0]
-      ::c_plbop();
-      ::c_plclear();
-      plstream::scolbg(red,green,blue); //resets col[0]
+  DByte r = (GraphicsDevice::GetDevice()->BackgroundR());
+  DByte g = (GraphicsDevice::GetDevice()->BackgroundG());
+  DByte b = (GraphicsDevice::GetDevice()->BackgroundB());
+  streamDC->SetBackground(wxBrush(wxColour(r,g,b)));
+  streamDC->Clear();
+  Update(); //see #1509
 }
 
-//FALSE: REPLACE With Clear(DLong chan) as in X //TBD
-void GDLWXStream::Clear(DLong bColor) {
-  Clear();
+void GDLWXStream::Clear(DLong chan) {
+  DByte r = (GraphicsDevice::GetDevice()->BackgroundR());
+  DByte g = (GraphicsDevice::GetDevice()->BackgroundG());
+  DByte b = (GraphicsDevice::GetDevice()->BackgroundB());
+  wxBitmap bmp=streamDC->GetAsBitmap();
+  wxImage image=bmp.ConvertToImage();
+  unsigned char* pixels=image.GetData();
+  SizeT size=image.GetHeight()*image.GetWidth();
+  DByte* colorComponent=&r;
+    switch(chan){
+      case 0: //R
+        colorComponent=&r;
+        break;
+      case 1:
+        colorComponent=&g;
+        break;
+      case 2:
+        colorComponent=&b;
+        break;
+    }
+  for (auto i=0; i<size; ++i) pixels[3*i+chan]=*colorComponent; 
+  streamDC->DrawBitmap(wxBitmap(image,3),0,0);
+  Update(); //see #1509
 }
+
 #include <wx/rawbmp.h>
 bool GDLWXStream::PaintImage(unsigned char *idata, PLINT nx, PLINT ny, DLong *pos,
         DLong trueColorOrder, DLong chan) {

src/gdlwxstream.hpp

@@ -71,7 +71,7 @@ class GDLWXStream: public GDLGStream
 //    bool UnsetFocus(); UnsetFocus is dangerous: it prevents using wxEvents correctly.
     bool SetBackingStore(int value){return true;}
     void Clear();
-    void Clear( DLong bColor);
+    void Clear( DLong chan);
     void Raise();
     void Lower();
     void Iconic();

src/gdlxstream.cpp

@@ -140,29 +140,8 @@ void GDLXStream::GetGeometry(long& xSize, long& ySize) {
     return true;
   }
 
-// plplot 5.3 does not provide the clear function for c++
-
 void GDLXStream::Clear() {
   Clear(-1);
-//  // this mimics better the *DL behaviour but plbop create a new page, etc..
-//  //plclear clears only the current subpage. But it clears it. One has
-//  //just to set the number of subpages to 1
-//  PLINT red, green, blue;
-//  DByte r, g, b;
-//  PLINT red0, green0, blue0;
-//
-//  GraphicsDevice::GetCT( )->Get( 0, r, g, b );
-//  red = r;
-//  green = g;
-//  blue = b;
-////we get around the index 0=background color "feature" of plplot. GDL uses a separate backgroud color.
-//  red0 = GraphicsDevice::GetDevice( )->BackgroundR( );
-//  green0 = GraphicsDevice::GetDevice( )->BackgroundG( );
-//  blue0 = GraphicsDevice::GetDevice( )->BackgroundB( );
-//  plstream::scolbg( red0, green0, blue0 ); //overwrites col[0]
-//  ::c_plbop( );
-////  ::c_plclear( );
-//  plstream::scolbg( red, green, blue ); //resets col[0]
 }
 
 void GDLXStream::Clear(DLong chan) {