fix subwindow.

src/nodesnim/nodescontrol/subwindow.nim

@@ -115,7 +115,7 @@ method draw*(self: SubWindowRef, w, h: GLfloat) =
   self.title.calcGlobalPosition()
   self.title.draw(w, h)
 
-  if self.icon.texture > 0:
+  if self.icon.texture > 0'u32:
     glEnable(GL_TEXTURE_2D)
     glBindTexture(GL_TEXTURE_2D, self.icon.texture)
     glBegin(GL_QUADS)