Fix for issue #159 - continued

Changes here concentrate the fix within static function alpha_blend() and thus
are visible only when drawing transparent images under X11 platform
without Xrender.

1 files changed, 6 insertions, 4 deletions

diff --git a/src/drivers/Xlib/Fl_Xlib_Graphics_Driver_image.cxx b/src/drivers/Xlib/Fl_Xlib_Graphics_Driver_image.cxx
index c7a811262..2dc9a76aa 100644
--- a/src/drivers/Xlib/Fl_Xlib_Graphics_Driver_image.cxx
+++ b/src/drivers/Xlib/Fl_Xlib_Graphics_Driver_image.cxx
@@ -658,13 +658,15 @@ static void alpha_blend(Fl_RGB_Image *img, int X, int Y, int W, int H, int cx, i
   int ld = img->ld();
   if (ld == 0) ld = img->data_w() * img->d();
   uchar *srcptr = (uchar*)img->array + cy * ld + cx * img->d();
-  int srcskip = ld - img->d() * W;
 
-  uchar *dst = new uchar[W * H * 3];
+  uchar *dst = fl_read_image(NULL, X, Y, W, H, 0);
+  if (!dst) {
+    fl_draw_image(srcptr, X, Y, W, H, img->d(), ld);
+    return;
+  }
+  int srcskip = ld - img->d() * W;
   uchar *dstptr = dst;
 
-  fl_read_image(dst, X, Y, W, H, 0);
-
   uchar srcr, srcg, srcb, srca;
   uchar dstr, dstg, dstb, dsta;