Added Fl_Shared_Image::scale(width, height) to support scaled image drawing (STR #3185).

Useful for printing, PostScript or PDF output, or retina displays.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@10615 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 29 insertions, 0 deletions

diff --git a/src/Fl_Pixmap.cxx b/src/Fl_Pixmap.cxx
index 8064979dd..2bb776b6b 100644
--- a/src/Fl_Pixmap.cxx
+++ b/src/Fl_Pixmap.cxx
@@ -135,6 +135,21 @@ void Fl_Quartz_Graphics_Driver::draw(Fl_Pixmap *pxm, int XP, int YP, int WP, int
   copy_offscreen(X, Y, W, H, (Fl_Offscreen)pxm->id_, cx, cy);
 }
 
+int Fl_Quartz_Graphics_Driver::draw_scaled(Fl_Pixmap *img, int XP, int YP, int WP, int HP) {
+  int X, Y, W, H;
+  fl_clip_box(XP,YP,WP,HP,X,Y,W,H); // X,Y,W,H will give the unclipped area of XP,YP,WP,HP
+  if (W == 0 || H == 0) return 1;
+  fl_push_no_clip(); // remove the FLTK clip that can't be rescaled
+  CGContextSaveGState(fl_gc);
+  CGContextClipToRect(fl_gc, CGRectMake(X, Y, W, H)); // this clip path will be rescaled & translated
+  CGContextTranslateCTM(fl_gc, XP, YP);
+  CGContextScaleCTM(fl_gc, float(WP)/img->w(), float(HP)/img->h());
+  draw(img, 0, 0, img->w(), img->h(), 0, 0);
+  CGContextRestoreGState(fl_gc);
+  fl_pop_clip(); // restore FLTK's clip
+  return 1;
+}
+
 #elif defined(WIN32)
 void Fl_GDI_Graphics_Driver::draw(Fl_Pixmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy) {
   int X, Y, W, H;
@@ -181,6 +196,20 @@ void Fl_GDI_Printer_Graphics_Driver::draw(Fl_Pixmap *pxm, int XP, int YP, int WP
   }
 }
 
+int Fl_GDI_Printer_Graphics_Driver::draw_scaled(Fl_Pixmap *img, int XP, int YP, int WP, int HP) {
+  XFORM old_tr, tr;
+  GetWorldTransform(fl_gc, &old_tr); // storing old transform
+  tr.eM11 = float(WP)/float(img->w());
+  tr.eM22 = float(HP)/float(img->h());
+  tr.eM12 = tr.eM21 = 0;
+  tr.eDx =  XP;
+  tr.eDy =  YP;
+  ModifyWorldTransform(fl_gc, &tr, MWT_LEFTMULTIPLY);
+  draw(img, 0, 0, img->w(), img->h(), 0, 0);
+  SetWorldTransform(fl_gc, &old_tr);
+}
+
+
 #else // Xlib
 void Fl_Xlib_Graphics_Driver::draw(Fl_Pixmap *pxm, int XP, int YP, int WP, int HP, int cx, int cy) {
   int X, Y, W, H;